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Pagoulatou S, Adamopoulos D, Rovas G, Bikia V, Müller H, Giannakopoulos G, Mauler-Wittwer S, Licker MJ, Stergiopulos N, Noble S. Arterial Wave Reflection and Aortic Valve Stenosis: Diagnostic Challenges and Prognostic Significance. Front Cardiovasc Med 2022; 9:863968. [PMID: 35872923 PMCID: PMC9304587 DOI: 10.3389/fcvm.2022.863968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
IntroductionArterial wave reflection is an important component of the left ventricular afterload, affecting both pressure and flow to the aorta. The aim of the present study was to evaluate the impact of wave reflection on transvalvular pressure gradients (TPG), a key parameter for the evaluation of aortic valve stenosis (AS), as well as its prognostic significance in patients with AS undergoing a transcatheter aortic valve replacement (TAVR).Materials and MethodsThe study population consisted of 351 patients with AS (mean age 84 ± 6 years, 43% males) who underwent a complete hemodynamic evaluation before the TAVR. The baseline assessment included right and left heart catheterization, transthoracic echocardiography, and a thorough evaluation of the left ventricular afterload by means of wave separation analysis. The cohort was divided into quartiles according to the transit time of the backward pressure wave (BWTT). Primary endpoint was all-cause mortality at 1 year.ResultsEarly arrival of the backward pressure wave was related to lower cardiac output (Q1: 3.7 ± 0.9 lt/min vs Q4: 4.4 ± 1.0 lt/min, p < 0.001) and higher aortic systolic blood pressure (Q1: 132 ± 26 mmHg vs Q4: 117 ± 26 mmHg, p < 0.001). TPG was significantly related to the BWTT, patients in the arrival group exhibiting the lowest TPG (mean TPG, Q1: 37.6 ± 12.7 mmHg vs Q4: 44.8 ± 14.7 mmHg, p = 0.005) for the same aortic valve area (AVA) (Q1: 0.58 ± 0.35 cm2 vs 0.61 ± 0.22 cm2, p = 0.303). In multivariate analysis, BWTT remained an independent determinant of mean TPG (beta 0.3, p = 0.002). Moreover, the prevalence of low-flow, low-gradient AS with preserved ejection fraction was higher in patients with early arterial reflection arrival (Q1: 33.3% vs Q4: 14.9%, p = 0.033). Finally, patients with early arrival of the reflected wave (Q1) exhibited higher all-cause mortality at 1 year after the TAVR (unadjusted HR: 2.33, 95% CI: 1.17–4.65, p = 0.016).ConclusionEarly reflected wave arrival to the aortic root is associated with poor prognosis and significant aortic hemodynamic alterations in patients undergoing a TAVR for AS. This is related to a significant decrease in TPG for a given AVA, leading to a possible underestimation of the AS severity.
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Affiliation(s)
- Stamatia Pagoulatou
- Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Dionysios Adamopoulos
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Department of Cardiology, Hôpitaux Universitaires de Genève (HUG), Geneva, Switzerland
- *Correspondence: Dionysios Adamopoulos,
| | - Georgios Rovas
- Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Vasiliki Bikia
- Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Hajo Müller
- Department of Cardiology, Hôpitaux Universitaires de Genève (HUG), Geneva, Switzerland
| | | | - Sarah Mauler-Wittwer
- Department of Cardiology, Hôpitaux Universitaires de Genève (HUG), Geneva, Switzerland
| | - Marc-Joseph Licker
- Department of Anaesthesiology, Hôpitaux Universitaires de Genève (HUG), Geneva, Switzerland
| | - Nikolaos Stergiopulos
- Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Stéphane Noble
- Department of Cardiology, Hôpitaux Universitaires de Genève (HUG), Geneva, Switzerland
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2
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Tyberg JV. Wave propagation and reflection in the aorta and implications of the aortic Windkessel. EXPLORATION OF MEDICINE 2021. [DOI: 10.37349/emed.2021.00042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Some have said that it is inappropriate and perhaps impossible to consider wave and Windkessel phenomena simultaneously. For 50 years, arterial hemodynamics has been dominated by the frequency-domain “impedance analysis” in which it was assumed that all variations in aortic pressure and flow were caused only by forward- and backward-going waves. This paper is a review of the results of incorporating the effects of Frank’s Windkessel. We have taken the view that measured aortic pressure is the sum of a Windkessel component and forward-going and backward-going wave components. When the Windkessel component is initially subtracted out, the pattern of propagation and reflection of wave components becomes clear. Furthermore, this analysis obviates the implications of impedance analysis that have not been explained satisfactorily.
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Affiliation(s)
- John V. Tyberg
- Emeritus Professor of Cardiac Sciences and Physiology/Pharmacology, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada
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3
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Sekma A, Bel Haj Ali K, Jeddi C, Ben Brahim N, Bzeouich N, Gannoun I, Trabelssi I, Laouiti K, Grissa MH, Beltaief K, Zohra D, Asma Z, Lotfi B, Rym Y, Ben Soltane H, Zied M, Mariem K, Msolli MA, Riadh B, Bouida W, Boubaker H, Nouira S. Value of nitroglycerin test in the diagnosis of heart failure in emergency department patients with undifferentiated dyspnea. Clin Cardiol 2021; 44:932-937. [PMID: 34076282 PMCID: PMC8259157 DOI: 10.1002/clc.23615] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 04/07/2021] [Accepted: 04/19/2021] [Indexed: 01/06/2023] Open
Abstract
Background Rapid diagnosis of heart failure (HF) in acutely dyspneic patients can be challenging for emergency department (ED) physicians. Hypothesis Cardiac output (CO) change with sublingual nitroglycerin (NTG) could be helpful in the diagnosis of HF in patients with acute undifferentiated dyspnea. Materials and Methods A prospective study of patients >18 years admitted to the ED for acute dyspnea. Using thoracic bioimpedance, we measured CO change at baseline and after sublingual administration of 0.6 mg of NTG. HF was defined on the basis of clinical examination, pro‐brain natriuretic peptide levels, and echocardiographic findings. Diagnostic performance of delta CO was calculated by sensitivity, specificity, likelihood ratio and receiver operating characteristic (ROC) curve. Results This study included 184 patients with mean age of 64 years. Baseline CO was comparable between the HF group and the non‐HF group. At its best cutoff (29%), delta CO showed good accuracy in the diagnosis of HF with a sensitivity, specificity, positive and negative likelihood ratios of 80%, 44%, 57%, and 66% respectively. Area under ROC curve was 0.701 [95% CI 0.636–0.760]. The decrease of CO with sublingual NTG was significantly higher in patients with HFpEF compared with those with HFrEF. Multivariate analysis, showed that delta CO was an independent factor associated with HF diagnosis [OR 0.19 (95% CI 0.11–0.29); p < .001]. Conclusions Our study showed that CO change with sublingual nitroglycerin is a simple tool that may be helpful for the diagnosis of HF in ED patients with undifferentiated dyspnea.
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Affiliation(s)
- Adel Sekma
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Khaoula Bel Haj Ali
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Camilia Jeddi
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Nadia Ben Brahim
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Nasri Bzeouich
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Imen Gannoun
- Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Imen Trabelssi
- Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Kamel Laouiti
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Mohamed Habib Grissa
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Kaouthar Beltaief
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Dridi Zohra
- Cardiology Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia
| | - Zorgati Asma
- Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia.,Emergency Department, Sahloul University Hospital, Sousse, Tunisia
| | - Boukadida Lotfi
- Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia.,Emergency Department, Sahloul University Hospital, Sousse, Tunisia
| | - Youssef Rym
- Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia.,Emergency Department, Sahloul University Hospital, Sousse, Tunisia
| | - Houda Ben Soltane
- Emergency Department, Farhat Hached University Hospital, Sousse, Tunisia
| | - Mezgar Zied
- Emergency Department, Farhat Hached University Hospital, Sousse, Tunisia
| | - Khrouf Mariem
- Emergency Department, Farhat Hached University Hospital, Sousse, Tunisia
| | - Mohamed Amine Msolli
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Boukef Riadh
- Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia.,Emergency Department, Sahloul University Hospital, Sousse, Tunisia
| | - Wahid Bouida
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Hamdi Boubaker
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
| | - Semir Nouira
- Emergency Department, Fattouma Bourguiba University Hospital, Monastir, Tunisia.,Research Laboratory LR12SP18, University of Monastir, Monastir, Tunisia
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Patik JC, Stock JM, Shenouda N, Chouramanis NV, Mehrer JD, Chirinos JA, Edwards DG. Pulsatile load and wasted pressure effort are reduced following an acute bout of aerobic exercise. J Appl Physiol (1985) 2021; 131:184-191. [PMID: 33982596 DOI: 10.1152/japplphysiol.00946.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Following aerobic exercise, sustained vasodilation and concomitant reductions in total peripheral resistance (TPR) result in a reduction in blood pressure that is maintained for two or more hours. However, the time course for postexercise changes in reflected wave amplitude and other indices of pulsatile load on the left ventricle have not been thoroughly described. Therefore, we tested the hypothesis that reflected wave amplitude is reduced beyond an hour after cycling at 60% V̇o2peak for 60 min. Aortic pressure waveforms were derived in 14 healthy adults (7 men, 7 women; 26 ± 3 yr) from radial pulse waves acquired via high-fidelity applanation tonometry at baseline and every 20 min for 120 min postexercise. Concurrently, left ventricle outflow velocities were acquired via Doppler echocardiography and pressure-flow analyses were performed. Aortic characteristic impedance (Zc), forward (Pf) and backward (Pb) pulse wave amplitude, reflected wave travel time (RWTT), and wasted pressure effort (WPE) were derived. Reductions in aortic blood pressure, Zc, Pf, and Pb were all sustained postexercise whereas increases in RWTT emerged from 60 to 100 min post exercise (all P < 0.05). WPE was reduced by ∼40% from 40 to 100 min post exercise (all P < 0.02). Stepwise multiple regression analysis revealed that the peak ΔWPE was associated with ΔRWTT (β = -0.57, P = 0.003) and ΔPb (β = 0.52, P = 0.006), but not Δcardiac output, ΔTPR, ΔZc, or ΔPf. These results suggest that changes in pulsatile hemodynamics are sustained for ≥100 min following moderate intensity aerobic exercise. Moreover, decreased and delayed reflected pressure waves are associated with decreased left ventricular wasted effort after exercise.NEW & NOTEWORTHY We demonstrate that pulsatile load on the left ventricle is diminished following 60 min of moderate intensity aerobic exercise. During recovery from exercise, the amplitude of the forward and backward traveling pressure waves are attenuated and the arrival of reflected waves is delayed. Thus, the work imposed upon the left ventricle by reflected pressure waves, wasted pressure effort, is decreased after exercise.
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Affiliation(s)
- Jordan C Patik
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
| | - Joseph M Stock
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
| | - Ninette Shenouda
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
| | - Nicholas V Chouramanis
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
| | - Justin D Mehrer
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
| | - Julio A Chirinos
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - David G Edwards
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
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5
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Mills CE, Govoni V, Faconti L, Casagrande M, Morant SV, Crickmore H, Iqbal F, Maskell P, Masani A, Nanino E, Webb AJ, Cruickshank JK. A randomised, factorial trial to reduce arterial stiffness independently of blood pressure: Proof of concept? The VaSera trial testing dietary nitrate and spironolactone. Br J Clin Pharmacol 2020; 86:891-902. [PMID: 31833569 PMCID: PMC7163378 DOI: 10.1111/bcp.14194] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 11/21/2019] [Accepted: 11/24/2019] [Indexed: 12/23/2022] Open
Abstract
AIMS To test if spironolactone or dietary nitrate from beetroot juice could reduce arterial stiffness as aortic pulse wave velocity (PWVart), a potential treatment target, independently of blood pressure. METHODS Daily spironolactone (≤50 mg) vs doxazosin (control ≤16 mg) and 70 mL beetroot juice (Beet-It ≤11 mmol nitrate) vs nitrate-depleted juice (placebo; 0 mmol nitrate) were tested in people at risk or with type-2 diabetes using a double-blind, 6-month factorial trial. Vascular indices (baseline, 12, 24 weeks) were cardiac-ankle vascular index (CAVI), a nominally pressure-independent stiffness measure (primary outcome), PWVart secondary, central systolic pressure and augmentation. Analysis was intention-to-treat, adjusted for systolic pressure differences between trial arms. RESULTS Spironolactone did not reduce stiffness, with evidence for reduced CAVI on doxazosin rather than spironolactone (mean difference [95% confidence interval]; 0.25 [-0.3, 0.5] units, P = .080), firmer for PWVart (0.37 [0.01, 0.7] m/s, P = .045). There was no difference in systolic pressure reduction between spironolactone and doxazosin (0.7 [-4.8, 3.3] mmHg, P = .7). Circulating nitrate and nitrite increased on active vs placebo juice, with central systolic pressure lowered -2.6 [-4.5, - 0.8] mmHg, P = .007 more on the active juice, but did not reduce CAVI, PWVart or peripheral pressure. Change in nitrate and nitrite concentrations were 1.5-fold [1.1-2.2] and 2.2-fold [1.3, 3.6] higher on spironolactone than on doxazosin respectively; both P < .05. CONCLUSION Contrary to our hypothesis, in at-risk/type 2 diabetes patients, spironolactone did not reduce arterial stiffness, rather PWVart was lower on doxazosin. Dietary nitrate elevated plasma nitrite, selectively lowering central systolic pressure, observed previously for nitrite.
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Affiliation(s)
- Charlotte E. Mills
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
- Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional SciencesUniversity of ReadingUK
| | - Virginia Govoni
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
| | - Luca Faconti
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
- King's College London British Heart Foundation Centre, School of Cardiovascular Medicine and Sciences, Department of Clinical PharmacologyUK
| | - Maria‐Linda Casagrande
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
| | | | - Hannah Crickmore
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
| | - Fahad Iqbal
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
| | - Perry Maskell
- Medicines Monitoring Unit (MEMO)University of DundeeUK
| | - Alisha Masani
- Medicines Monitoring Unit (MEMO)University of DundeeUK
| | - Elisa Nanino
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
| | - Andrew J. Webb
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
- King's College London British Heart Foundation Centre, School of Cardiovascular Medicine and Sciences, Department of Clinical PharmacologyUK
| | - J. Kennedy Cruickshank
- Cardiovascular Medicine Group, Department of Nutritional SciencesSchool of Life Course SciencesKing's College LondonUK
- Biomedical Research Centre, Clinical Research Facility, 4 Floor, North Wing, St Thomas' Hospital, Guy's and St Thomas' NHS Foundation TrustLondonUK
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6
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Londono-Hoyos F, Zamani P, Beraun M, Vasim I, Segers P, Chirinos JA. Effect of organic and inorganic nitrates on cerebrovascular pulsatile power transmission in patients with heart failure and preserved ejection fraction. Physiol Meas 2018; 39:044001. [PMID: 29488900 DOI: 10.1088/1361-6579/aab2ef] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Increased penetration of pulsatile power to the brain has been implicated in the pathogenesis of age-related cognitive dysfunction and dementia, a common comorbidity in patients with heart failure and preserved ejection fraction (HFpEF). However, there is a lack of knowledge on the effects of organic and inorganic nitrates administration in this population on the power carried by pressure and flow waves traveling through the proximal aorta and penetrating the carotid artery into the brain microvasculature. APPROACH We assessed aortic and carotid hemodynamics non-invasively in two sub-studies: (1) at baseline and after administration of 0.4 mg of sublingual nitroglycerine (an organic nitrate; n = 26); and (2) in a randomized controlled trial of placebo (PB) versus inorganic nitrate administration (beetroot-juice (BR), 12.9 mmol NO3; n = 16). MAIN RESULTS Wave and hydraulic power analysis demonstrated that NTG increased total hydraulic power (from 5.68% at baseline to 8.62%, P = 0.001) and energy penetration (from 8.69% to 11.63%; P = 0.01) from the aorta to the carotid, while inorganic nitrate administration did not induce significant changes in aortic and carotid wave power (power: 5.49%PB versus 6.25%BR, P = 0.49; energy: 8.89%PB versus 10.65%BR, P = 0.27). SIGNIFICANCE Organic nitrates, but not inorganic nitrates, increase the amount of hydraulic energy transmitted into the carotid artery in subjects with HFpEF. These findings may have implications for the adverse effect profiles of these agents (such as the differential incidence of headaches) and for the pulsatile hemodynamic stress of the brain microvasculature in this patient population.
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Affiliation(s)
- Francisco Londono-Hoyos
- University of Pennsylvania Perelman School of Medicine Hospital of the University of Pennsylvania, Philadelphia, PA, United States of America. Institute Biomedical Technology (IBiTech)-bioMMeda Research Group-Ghent University, Ghent, Belgium. FLH and PZ contributed equally to this manuscript
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7
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Tyberg JV, Burrowes LM, Shrive NG, Wang JJ. Origin of the forward-going "backward" wave. J Appl Physiol (1985) 2017; 123:1406-1407. [PMID: 28663376 DOI: 10.1152/japplphysiol.00350.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/13/2017] [Accepted: 06/27/2017] [Indexed: 01/09/2023] Open
Affiliation(s)
- John V Tyberg
- Departments of Cardiac Sciences and Physiology/Pharmacology, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada;
| | - Lindsay M Burrowes
- Departments of Cardiac Sciences and Physiology/Pharmacology, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
| | - Nigel G Shrive
- Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB, Canada; and
| | - Jiun-Jr Wang
- Department of Medicine, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
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8
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Chirinos JA, Londono-Hoyos F, Zamani P, Beraun M, Haines P, Vasim I, Varakantam S, Phan TS, Cappola TP, Margulies KB, Townsend RR, Segers P. Effects of organic and inorganic nitrate on aortic and carotid haemodynamics in heart failure with preserved ejection fraction. Eur J Heart Fail 2017; 19:1507-1515. [PMID: 28547861 DOI: 10.1002/ejhf.885] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 04/04/2017] [Accepted: 04/10/2017] [Indexed: 01/23/2023] Open
Abstract
AIMS To assess the haemodynamic effects of organic vs. inorganic nitrate administration among patients with heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS We assessed carotid and aortic pressure-flow relations non-invasively before and after the administration of 0.4 mg of sublingual nitroglycerin (n = 26), and in a separate sub-study, in response to 12.9 mmoL of inorganic nitrate (n = 16). Nitroglycerin did not consistently reduce wave reflections arriving at the proximal aorta (change in real part of reflection coefficient, 1st harmonic: -0.09; P = 0.01; 2nd harmonic: -0.045, P = 0.16; 3rd harmonic: +0.087; P = 0.05), but produced profound vasodilatation in the carotid territory, with a significant reduction in systolic blood pressure (133.6 vs. 120.5 mmHg; P = 0.011) and a marked reduction in carotid bed vascular resistance (19 580 vs. 13 078 dynes · s/cm5 ; P = 0.001) and carotid characteristic impedance (3440 vs. 1923 dynes · s/cm5 ; P = 0.002). Inorganic nitrate, in contrast, consistently reduced wave reflections across the first three harmonics (change in real part of reflection coefficient, 1st harmonic: -0.12; P = 0.03; 2nd harmonic: -0.11, P = 0.01; 3rd harmonic: -0.087; P = 0.09) and did not reduce blood pressure, carotid bed vascular resistance, or carotid characteristic impedance (P = NS). CONCLUSIONS Nitroglycerin produces marked vasodilatation in the carotid circulation, with a pronounced reduction in blood pressure and inconsistent effects on central wave reflections. Inorganic nitrate, in contrast, produces consistent reductions in wave reflections, and unlike nitroglycerin, it does so without significant hypotension or cerebrovascular dilatation. These haemodynamic differences may underlie the different effects on exercise capacity and side effect profile of inorganic vs. organic nitrate in HFpEF.
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Affiliation(s)
- Julio A Chirinos
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Francisco Londono-Hoyos
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA.,Institute of Biomedical Technology, Ghent University, Ghent, Belgium
| | - Payman Zamani
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Melissa Beraun
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Philip Haines
- Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Izzah Vasim
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA.,Philadelphia VA Medical Center, Philadelphia, PA, USA
| | - Swapna Varakantam
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA.,Philadelphia VA Medical Center, Philadelphia, PA, USA
| | - Timothy S Phan
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Thomas P Cappola
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Kenneth B Margulies
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Raymond R Townsend
- University of Pennsylvania Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Patrick Segers
- Institute of Biomedical Technology, Ghent University, Ghent, Belgium
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9
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Zamani P, Akers S, Soto-Calderon H, Beraun M, Koppula MR, Varakantam S, Rawat D, Shiva-Kumar P, Haines PG, Chittams J, Townsend RR, Witschey WR, Segers P, Chirinos JA. Isosorbide Dinitrate, With or Without Hydralazine, Does Not Reduce Wave Reflections, Left Ventricular Hypertrophy, or Myocardial Fibrosis in Patients With Heart Failure With Preserved Ejection Fraction. J Am Heart Assoc 2017; 6:JAHA.116.004262. [PMID: 28219917 PMCID: PMC5523746 DOI: 10.1161/jaha.116.004262] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Background Wave reflections, which are increased in patients with heart failure with preserved ejection fraction, impair diastolic function and promote pathologic myocardial remodeling. Organic nitrates reduce wave reflections acutely, but whether this is sustained chronically or affected by hydralazine coadministration is unknown. Methods and Results We randomized 44 patients with heart failure with preserved ejection fraction in a double‐blinded fashion to isosorbide dinitrate (ISDN; n=13), ISDN+hydralazine (ISDN+hydral; n=15), or placebo (n=16) for 6 months. The primary end point was the change in reflection magnitude (RM; assessed with arterial tonometry and Doppler echocardiography). Secondary end points included change in left ventricular mass and fibrosis, measured with cardiac magnetic resonance imaging, and the 6‐minute walk distance. ISDN reduced aortic characteristic impedance (mean baseline=0.15 [95% CI, 0.14–0.17], 3 months=0.11 [95% CI, 0.10–0.13], 6 months=0.10 [95% CI, 0.08–0.12] mm Hg/mL per second; P=0.003) and forward wave amplitude (Pf, mean baseline=54.8 [95% CI, 47.6–62.0], 3 months=42.2 [95% CI, 33.2–51.3]; 6 months=37.0 [95% CI, 27.2–46.8] mm Hg, P=0.04), but had no effect on RM (P=0.64), left ventricular mass (P=0.33), or fibrosis (P=0.63). ISDN+hydral increased RM (mean baseline=0.39 [95% CI, 0.35–0.43]; 3 months=0.31 [95% CI, 0.25–0.36]; 6 months=0.44 [95% CI, 0.37–0.51], P=0.03), reduced 6‐minute walk distance (mean baseline=343.3 [95% CI, 319.2–367.4]; 6 months=277.0 [95% CI, 242.7–311.4] meters, P=0.022), and increased native myocardial T1 (mean baseline=1016.2 [95% CI, 1002.7–1029.7]; 6 months=1054.5 [95% CI, 1036.5–1072.3], P=0.021). A high proportion of patients experienced adverse events with active therapy (ISDN=61.5%, ISDN+hydral=60.0%; placebo=12.5%; P=0.007). Conclusions ISDN, with or without hydralazine, does not exert beneficial effects on RM, left ventricular remodeling, or submaximal exercise and is poorly tolerated. ISDN+hydral appears to have deleterious effects on RM, myocardial remodeling, and submaximal exercise. Our findings do not support the routine use of these vasodilators in patients with heart failure with preserved ejection fraction. Clinical Trial Registration URL: www.clinicaltrials.gov. Unique identifier: NCT01516346.
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Affiliation(s)
- Payman Zamani
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Scott Akers
- Department of Radiology, Philadelphia Veterans' Affairs Medical Center, Philadelphia, PA
| | - Haideliza Soto-Calderon
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Melissa Beraun
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Maheswara R Koppula
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Swapna Varakantam
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Deepa Rawat
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Prithvi Shiva-Kumar
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Philip G Haines
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA.,Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI
| | - Jesse Chittams
- Office of Nursing Research, School of Nursing, University of Pennsylvania, Philadelphia, PA
| | - Raymond R Townsend
- Division of Nephrology/Hypertension, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Walter R Witschey
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Patrick Segers
- Biofluid, Tissue, and Solid Mechanics for Medical Applications, IBiTech, iMinds Medical IT, Ghent University, Ghent, Belgium
| | - Julio A Chirinos
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA
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Li Y, Gu H, Fok H, Alastruey J, Chowienczyk P. Forward and Backward Pressure Waveform Morphology in Hypertension. Hypertension 2017; 69:375-381. [PMID: 27920128 PMCID: PMC5222553 DOI: 10.1161/hypertensionaha.116.08089] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 07/22/2016] [Accepted: 10/03/2016] [Indexed: 01/09/2023]
Abstract
We tested the hypothesis that increased pulse wave reflection and altered backward waveform morphology contribute to increased pulse pressure in subjects with higher pulse pressure compared with lower pulse pressure and to actions of vasoactive drugs to increase pulse pressure. We examined the relationship of backward to forward wave morphology in 158 subjects who were evaluated for hypertension (including some normotensive subjects) divided into 3 groups by central pulse pressure: group 1, 33±6.5 mm Hg; group 2, 45±4.1 mm Hg; and group 3, 64±12.9 mm Hg (means±SD) and in healthy normotensive subjects during administration of inotropic and vasomotor drugs. Aortic pressure and flow in the aortic root were estimated by carotid tonometry and Doppler sonography, respectively. Morphology of the backward wave relative to the forward wave was similar in subjects in the lowest and highest tertiles of pulse pressure. Similar results were seen with the inotropic, vasopressor and vasodilator drugs, dobutamine, norepinephrine, and phentolamine, with the backward wave maintaining a constant ratio to the forward wave. However, nitroglycerin, a drug with a specific action to dilate muscular conduit arteries, reduced the amplitude of the backward wave relative to the forward wave from 0.26±0.018 at baseline to 0.19±0.019 during nitroglycerin 30 μg/min IV (P<0.01). These results are best explained by an approximately constant amount of reflection of the forward wave from the peripheral vasculature. The amount of reflection can be modified by dilation of peripheral muscular conduit arteries but contributes little to increased pulse pressure in hypertension.
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Affiliation(s)
- Ye Li
- From the British Heart Foundation Centre (Y.L., H.G., H.F., P.C.) and Division of Imaging Sciences and Biomedical Engineering (J.A.), King's College London, United Kingdom
| | - Haotian Gu
- From the British Heart Foundation Centre (Y.L., H.G., H.F., P.C.) and Division of Imaging Sciences and Biomedical Engineering (J.A.), King's College London, United Kingdom
| | - Henry Fok
- From the British Heart Foundation Centre (Y.L., H.G., H.F., P.C.) and Division of Imaging Sciences and Biomedical Engineering (J.A.), King's College London, United Kingdom
| | - Jordi Alastruey
- From the British Heart Foundation Centre (Y.L., H.G., H.F., P.C.) and Division of Imaging Sciences and Biomedical Engineering (J.A.), King's College London, United Kingdom
| | - Philip Chowienczyk
- From the British Heart Foundation Centre (Y.L., H.G., H.F., P.C.) and Division of Imaging Sciences and Biomedical Engineering (J.A.), King's College London, United Kingdom.
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11
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Central pressures and central hemodynamic values in white coat hypertensives are closer to those of normotensives than to those of controlled hypertensives for similar age, gender, and 24-h and nocturnal blood pressures. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2016. [DOI: 10.1016/j.repce.2016.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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12
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Almeida J, Monteiro J, Silva JA, Bertoquini S, Polónia J. Central pressures and central hemodynamic values in white coat hypertensives are closer to those of normotensives than to those of controlled hypertensives for similar age, gender, and 24-h and nocturnal blood pressures. Rev Port Cardiol 2016; 35:559-567. [PMID: 27717519 DOI: 10.1016/j.repc.2016.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/23/2016] [Accepted: 05/30/2016] [Indexed: 11/26/2022] Open
Abstract
INTRODUCTION There is disagreement whether white coat hypertensives (WCH) have different hemodynamic and structural characteristics compared to normotensives (NT) and hypertensives (HT). METHODS We compared cardiovascular prognostic markers (pulse wave velocity [PWV] and aortic stiffness index [ASI]) and data on central hemodynamics and central pressures (augmentation index [AIx], augmentation pressure [AugP] and pulse pressure amplification [PPA]) from aortic pulse wave analysis between NT (n=175), WCH (n=315) and treated HT (n=691), all with 24-h blood pressure (BP) <130/80 and nocturnal BP <120/70 mmHg after matching for age, gender, body mass index (BMI) and and nocturnal BP. The groups were also compared separately in terms of 24-h systolic BP <120 mmHg and 120-129 mmHg. RESULTS The percentage of non-dippers was 40.1% in NT, 34.5% in WCH and 38.3 in HT. For similar 24-h and nocturnal systolic BP (NT 109/64±7/5, WCH 110/66±7/6, HT 109/64±7/5 mmHg), aortic stiffness was greater in HT (n=691, PWV 10.8±2.6 m/s and ASI 0.33±0.16, p<0.01) than in WCH (n=316, PWV 9.7±2.4 m/s and ASI 0.28±0.17) and NT (n=175, PWV 9.5±2.0 m/s and ASI 0.29±0.15); AugP and AIx were higher (p<0.01) in HT (13.9±8.2 and 29.6±12.6 mmHg) than in WCH (11.5±8.5 mmHg and 24.9±15.2) and NT (11.0±6.4 mmHg and 26.6±11.5). PPA was lower (p<0.01) in HT (11.3±5.5 mmHg) than in WCH (13.2±7.1 mmHg) and in NT (12.4±4.9 mmHg). The findings were similar when the 24-h systolic BP <120 mmHg and 120-129 mmHg subgroups were analyzed separately. CONCLUSION Our data suggest that for similar age, gender distribution, BMI, and 24-h and nocturnal BP, aortic stiffness, central aortic pressures and wave reflection in WCH are closer to those of NT than to those with treated HT. This supports the idea that white coat hypertension may be a more benign condition than treated hypertension for similar 24-h and particularly nocturnal BP levels.
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Affiliation(s)
- Joana Almeida
- Departamento de Medicina e Cintesis, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - José Monteiro
- Departamento de Medicina e Cintesis, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - José A Silva
- Unidade de Hipertensão e RCV, Hospital Pedro Hispano, ULS Matosinhos, Matosinhos, Portugal
| | - Susana Bertoquini
- Departamento de Medicina e Cintesis, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - Jorge Polónia
- Departamento de Medicina e Cintesis, Faculdade de Medicina, Universidade do Porto, Porto, Portugal; Unidade de Hipertensão e RCV, Hospital Pedro Hispano, ULS Matosinhos, Matosinhos, Portugal.
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13
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Magnetic resonance and applanation tonometry for noninvasive determination of left ventricular load and ventricular vascular coupling in the time and frequency domain. J Hypertens 2016; 34:1099-108. [DOI: 10.1097/hjh.0000000000000925] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Namasivayam M, Adji A, O'Rourke MF. Evaluating the Hemodynamic Basis of Age-Related Central Blood Pressure Change Using Aortic Flow Triangulation. Am J Hypertens 2016; 29:178-84. [PMID: 26045532 DOI: 10.1093/ajh/hpv080] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 05/05/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Pulsatile blood pressure rises with age, especially in the aorta. The comparative role of forward and reflected pressure waves (FW and RW, respectively), determined by aortic flow triangulation has not previously been explored in a large clinical cohort. This study aimed to identify the role of FW and RW in the rise in aortic pulse pressure with age. METHODS For 879 outpatients, aortic pressure waveforms were generated using a validated generalized transfer function applied to radial pressure waves recorded using applanation tonometry. FW and RW were subsequently determined using aortic flow triangulation. Contributions of FW and RW to rise in aortic pulse pressure with age were determined using multivariate linear regression and product of coefficient mediation analysis, with adjustment for height, weight, heart rate, and mean arterial pressure. Comparisons were made by gender and before and after age 60. RESULTS In subjects aged 60 and below, RW was an important contributor to pulsatile pressure elevation with age, but FW was non-contributory in either gender after multivariate correction. In subjects aged above 60, both FW and RW were significant and equal contributors in both genders. CONCLUSIONS In a clinical setting, both FW and RW are important to pulsatile aortic blood pressure across the lifespan, but RW appears to have a more pronounced effect across all ages, whereas FW has less effect in younger persons.
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Affiliation(s)
- Mayooran Namasivayam
- Department of Cardiology, St. Vincent's Hospital and Clinic, Sydney, Australia; Faculty of Medicine, University of New South Wales, Sydney Australia; Vascular-Ventricular Interactions Laboratory, Cardiac Physiology and Transplantation Division, Victor Chang Cardiac Research Institute, Sydney, Australia
| | - Audrey Adji
- Department of Cardiology, St. Vincent's Hospital and Clinic, Sydney, Australia; Vascular-Ventricular Interactions Laboratory, Cardiac Physiology and Transplantation Division, Victor Chang Cardiac Research Institute, Sydney, Australia; Australian School of Advanced Medicine, Macquarie University, Sydney, Australia
| | - Michael F O'Rourke
- Department of Cardiology, St. Vincent's Hospital and Clinic, Sydney, Australia; Faculty of Medicine, University of New South Wales, Sydney Australia; Vascular-Ventricular Interactions Laboratory, Cardiac Physiology and Transplantation Division, Victor Chang Cardiac Research Institute, Sydney, Australia;
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Wu CF, Liu PY, Wu TJ, Hung Y, Yang SP, Lin GM. Therapeutic modification of arterial stiffness: An update and comprehensive review. World J Cardiol 2015; 7:742-753. [PMID: 26635922 PMCID: PMC4660469 DOI: 10.4330/wjc.v7.i11.742] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/30/2015] [Accepted: 09/28/2015] [Indexed: 02/06/2023] Open
Abstract
Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with long-term worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovascular risk. Additionally to life style modifications, long-term ω-3 fatty acids (fish oil) supplementation in diet may improve arterial stiffness in the population with hypertension or metabolic syndrome. Pharmacological treatment such as renin-angiotensin-aldosterone system antagonists, metformin, and 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors were useful in individuals with hypertension and diabetes. In obese population with obstructive sleep apnea, weight reduction, aerobic exercise, and continuous positive airway pressure treatment may also improve arterial stiffness. In the populations with chronic inflammatory disease such as rheumatoid arthritis, a use of antibodies against tumor necrosis factor-alpha could work effectively. Other therapeutic options such as renal sympathetic nerve denervation for patients with resistant hypertension are investigated in many ongoing clinical trials. Therefore our comprehensive review provides knowledge in detail regarding many aspects of pathogenesis, measurement, and management of arterial stiffness in several populations, which would be helpful for physicians to make clinical decision.
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16
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Zanetti M, Grillo A, Losurdo P, Panizon E, Mearelli F, Cattin L, Barazzoni R, Carretta R. Omega-3 Polyunsaturated Fatty Acids: Structural and Functional Effects on the Vascular Wall. BIOMED RESEARCH INTERNATIONAL 2015; 2015:791978. [PMID: 26301252 PMCID: PMC4537737 DOI: 10.1155/2015/791978] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 01/26/2015] [Indexed: 01/24/2023]
Abstract
Omega-3 polyunsaturated fatty acids (n-3 PUFA) consumption is associated with reduced cardiovascular disease risk. Increasing evidence demonstrating a beneficial effect of n-3 PUFA on arterial wall properties is progressively emerging. We reviewed the recent available evidence for the cardiovascular effects of n-3 PUFA focusing on structural and functional properties of the vascular wall. In experimental studies and clinical trials n-3 PUFA have shown the ability to improve arterial hemodynamics by reducing arterial stiffness, thus explaining some of its cardioprotective properties. Recent studies suggest beneficial effects of n-3 PUFA on endothelial activation, which are likely to improve vascular function. Several molecular, cellular, and physiological pathways influenced by n-3 PUFA can affect arterial wall properties and therefore interfere with the atherosclerotic process. Although the relative weight of different physiological and molecular mechanisms and the dose-response on arterial wall properties have yet to be determined, n-3 PUFA have the potential to beneficially impact arterial wall remodeling and cardiovascular outcomes by targeting arterial wall stiffening and endothelial dysfunction.
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Affiliation(s)
- Michela Zanetti
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Andrea Grillo
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Pasquale Losurdo
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Emiliano Panizon
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Filippo Mearelli
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Luigi Cattin
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Rocco Barazzoni
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
| | - Renzo Carretta
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume 447, 34149 Trieste, Italy
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Chiba T, Yamanaka M, Takagi S, Shimizu K, Takahashi M, Shirai K, Takahara A. Cardio-ankle vascular index (CAVI) differentiates pharmacological properties of vasodilators nicardipine and nitroglycerin in anesthetized rabbits. J Pharmacol Sci 2015; 128:185-92. [PMID: 26238254 DOI: 10.1016/j.jphs.2015.07.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 06/29/2015] [Accepted: 07/03/2015] [Indexed: 10/23/2022] Open
Abstract
Cardio-ankle vascular index (CAVI) has been developed for measurement of vascular stiffness from the aorta to tibial artery, which is clinically utilized for assessing the progress of arteriosclerosis. In this study, we established measuring system of the CAVI in rabbits, and assessed whether the index could reflect different pharmacological actions of nitroglycerin and nicardipine on the systemic vasculature. Rabbits were anesthetized with halothane, and the CAVI was calculated from the well-established basic equations with variables obtained from brachial and tibial blood pressure and phonocardiogram. Nicardipine (1, 3 and 10 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and heart-ankle pulse wave velocity (haPWV). Meanwhile, no significant change was detected in the CAVI at the low or middle dose, which reflects the defining feature of the CAVI that is independent of blood pressure. The index increased at the high dose. Nitroglycerin (2, 4 and 8 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and haPWV. Meanwhile, the CAVI was decreased during the nitroglycerin infusion, which may reflect its well-known pharmacological action dilating conduit arteries. These results suggest that the CAVI differentiates the properties of these vasodilators in vivo.
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Affiliation(s)
- Tatsuo Chiba
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan; Department of Pharmacy, Toho University Ohashi Medical Center, Meguro-ku, Tokyo 153-8515, Japan
| | - Mari Yamanaka
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan
| | - Sachie Takagi
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan
| | - Kazuhiro Shimizu
- Cardiovascular Center, Toho University Sakura Medical Center, Sakura, Chiba 285-8741, Japan
| | - Mao Takahashi
- Cardiovascular Center, Toho University Sakura Medical Center, Sakura, Chiba 285-8741, Japan
| | - Kohji Shirai
- Department of Vascular Function, Toho University Sakura Medical Center, Chiba 285-8741, Japan; Mihama Hospital, Chiba 261-0013, Japan
| | - Akira Takahara
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan.
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Future Treatment of Hypertension: Shifting the Focus from Blood Pressure Lowering to Arterial Stiffness Modulation? Curr Hypertens Rep 2015; 17:67. [DOI: 10.1007/s11906-015-0569-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Alyami A, Soares MJ, Sherriff JL, Zhao Y, Hallett J, Coombes F. A systematic review protocol examining the effect of vitamin D supplementation on endothelial function. BMJ Open 2015; 5:e006835. [PMID: 26070793 PMCID: PMC4466623 DOI: 10.1136/bmjopen-2014-006835] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
INTRODUCTION Vitamin D has potential benefits for extraskeletal health. These could include an anti-inflammatory effect as well as a reduction in endothelial dysfunction. We aim to provide quality evidence for the hypothesis that supplementation with vitamin D will improve endothelial function (EF), possibly through the abrogation of systemic inflammation. METHODS AND ANALYSIS We will conduct a systematic review of all randomised controlled trials on vitamin D supplementation and EF lasting 12 weeks or more. The search will cover the period 2000-2015 and include studies that describe direct measures of EF, markers of endothelial cell (EC) activation and if concurrently reported, indicators of systemic inflammation. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and study quality will be assessed by the Jadad score in addition to an evaluation of allocation concealment and data analysis. If sufficient data are available, a meta-analysis will be conducted. The effect sizes will be generated using Hedges' g score, for both fixed and random effect models. I(2) statistics and Galbraith plots will be used to assess heterogeneity and identify their potential sources. Potential publication and small sample size bias will be assessed by visual inspections of funnel plots and also Egger's test. Meta-regression analysis (if feasible) will be conducted with restricted maximum likelihood (REML) estimation method, controlling for potential confounders (demographics, study methods, location, etc). A backward elimination process will be applied in the regression modelling procedure. Subgroup analysis, conditional on number of studies retrieved and their sample size, will be stratified on participant disease category, total dose administered, degree of 25(OH)D change and type of supplement used. ETHICS AND DISSEMINATION Formal ethical approval is not required as primary data will not be collected. The results will be disseminated through a peer-reviewed publication, conference presentation and the popular press. TRIAL REGISTRATION NUMBER International Prospective Register for Systematic Reviews (PROSPERO) number CRD42014013523.
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Affiliation(s)
- A Alyami
- Directorate of Nutrition, Dietetics & Food Technology, School of Public Health, Curtin Health Innovation Research Institute of Ageing & Chronic Disease, Curtin University, Perth, Western Australia, Australia
| | - MJ Soares
- Directorate of Nutrition, Dietetics & Food Technology, School of Public Health, Curtin Health Innovation Research Institute of Ageing & Chronic Disease, Curtin University, Perth, Western Australia, Australia
| | - JL Sherriff
- Directorate of Nutrition, Dietetics & Food Technology, School of Public Health, Curtin Health Innovation Research Institute of Ageing & Chronic Disease, Curtin University, Perth, Western Australia, Australia
| | - Y Zhao
- Directorate of Epidemiology & Biostatistics, School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - J Hallett
- Collaboration for Evidence, Research and Impact in Public Health, School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - F Coombes
- University Health Service, Support Services, Curtin University, Perth, Western Australia, Australia
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Everett TR, Wilkinson IB, Mahendru AA, McEniery CM, Garner SF, Goodall AH, Lees CC. S-Nitrosoglutathione improves haemodynamics in early-onset pre-eclampsia. Br J Clin Pharmacol 2015; 78:660-9. [PMID: 24627995 DOI: 10.1111/bcp.12379] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 03/10/2014] [Indexed: 01/23/2023] Open
Abstract
AIMS To determine the effects of in vivo S-nitrosoglutathione (GSNO) infusion on cardiovascular function, platelet function, proteinuria and biomarker parameters in early-onset pre-eclampsia. METHODS We performed an open-label dose-ranging study of GSNO in early-onset pre-eclampsia. Six women underwent GSNO infusion whilst receiving standard therapy. The dose of GSNO was increased incrementally to 100 μg min(-1) whilst maintaining blood pressure of >140/80 mmHg. Aortic augmentation index, aortic pulse wave velocity, blood pressure and maternal-fetal Doppler parameters were measured at each dose. Platelet P-selectin, protein-to-creatinine ratio and soluble anti-angiogenic factors were measured pre- and postinfusion. RESULTS Augmentation index fell at 30 μg min(-1) S-nitrosoglutathione (-6%, 95% confidence interval 0.6 to 13%), a dose that did not affect blood pressure. Platelet P-selectin expression was reduced [mean (interquartile range), 6.3 (4.9-7.6) vs. 4.1 (3.1-5.7)% positive, P = 0.03]. Soluble endoglin levels showed borderline reduction (P = 0.06). There was a borderline significant change in pre-to-postinfusion protein-to-creatinine ratio [mean (interquartile range), 0.37 (0.09-0.82) vs. 0.23 (0.07-0.49) g mmol(-1) , P = 0.06]. Maternal uterine and fetal Doppler pulsatility indices were unchanged. CONCLUSIONS In early-onset pre-eclampsia, GSNO reduces augmentation index, a biomarker of small vessel tone and pulse wave reflection, prior to affecting blood pressure. Proteinuria and platelet activation are improved at doses that affect blood pressure minimally. These effects of GSNO may be of therapeutic potential in pre-eclampsia, a condition for which no specific treatment exists. Clinical studies of GSNO in early-onset pre-eclampsia will determine whether these findings translate to improvement in maternal and/or fetal outcome.
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Affiliation(s)
- Thomas R Everett
- Fetal Medicine Department, Rosie Hospital, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, CB2 2QQ, UK
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Microvascular function. J Hypertens 2015; 33:928-30. [DOI: 10.1097/hjh.0000000000000538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zakeri R, Levine JA, Koepp GA, Borlaug BA, Chirinos JA, LeWinter M, VanBuren P, Dávila-Román VG, de Las Fuentes L, Khazanie P, Hernandez A, Anstrom K, Redfield MM. Nitrate's effect on activity tolerance in heart failure with preserved ejection fraction trial: rationale and design. Circ Heart Fail 2015; 8:221-8. [PMID: 25605640 DOI: 10.1161/circheartfailure.114.001598] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Rosita Zakeri
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - James A Levine
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Gabriel A Koepp
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Barry A Borlaug
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Julio A Chirinos
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Martin LeWinter
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Peter VanBuren
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Victor G Dávila-Román
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Lisa de Las Fuentes
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Prateeti Khazanie
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Adrian Hernandez
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Kevin Anstrom
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.)
| | - Margaret M Redfield
- From the Mayo Clinic, Rochester, MN (R.Z., B.A.B., M.M.R.); Mayo Clinic, Scottsdale, AZ (J.A.L., G.A.K.); University of Pennsylvania, Philadelphia (J.A.C.); University of Vermont College of Medicine, Burlington (M.L., P.V.); Washington University School of Medicine, St Louis, MO (V.G.D.-R., L.d.l.F.); and Duke Clinical Research Institute, Durham, NC (P.K., A.H., K.A.).
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Omar SA, Fok H, Tilgner KD, Nair A, Hunt J, Jiang B, Taylor P, Chowienczyk P, Webb AJ. Paradoxical normoxia-dependent selective actions of inorganic nitrite in human muscular conduit arteries and related selective actions on central blood pressures. Circulation 2015; 131:381-9; discussion 389. [PMID: 25533964 DOI: 10.1161/circulationaha.114.009554] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Inorganic nitrite dilates small resistance arterioles via hypoxia-facilitated reduction to vasodilating nitric oxide. The effects of nitrite in human conduit arteries have not been investigated. In contrast to nitrite, organic nitrates are established selective dilators of conduit arteries. METHODS AND RESULTS We examined the effects of local and systemic administration of sodium nitrite on the radial artery (a muscular conduit artery), forearm resistance vessels (forearm blood flow), and systemic hemodynamics in healthy male volunteers (n=43). Intrabrachial sodium nitrite (8.7 μmol/min) increased radial artery diameter by a median of 28.0% (25th and 75th percentiles, 25.7% and 40.1%; P<0.001). Nitrite (0.087-87 μmol/min) displayed conduit artery selectivity similar to that of glyceryl trinitrate (0.013-4.4 nmol/min) over resistance arterioles. Nitrite dose-dependently increased local cGMP production at the dose of 2.6 μmol/min by 1.1 pmol·min(-1)·100 mL(-1) tissue (95% confidence interval, 0.5-1.8). Nitrite-induced radial artery dilation was enhanced by administration of acetazolamide (oral or intra-arterial) and oral raloxifene (P=0.0248, P<0.0001, and P=0.0006, respectively) but was inhibited under hypoxia (P<0.0001) and hyperoxia (P=0.0006) compared with normoxia. Systemic intravenous administration of sodium nitrite (8.7 μmol/min) dilated the radial artery by 10.7% (95% confidence interval, 6.8-14.7) and reduced central systolic blood pressure by 11.6 mm Hg (95% confidence interval, 2.4-20.7), augmentation index, and pulse wave velocity without changing peripheral blood pressure. CONCLUSIONS Nitrite selectively dilates conduit arteries at supraphysiological and near-physiological concentrations via a normoxia-dependent mechanism that is associated with cGMP production and is enhanced by acetazolamide and raloxifene. The selective central blood pressure-lowering effects of nitrite have therapeutic potential to reduce cardiovascular events.
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Affiliation(s)
- Sami A Omar
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Henry Fok
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Katharina D Tilgner
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Ashok Nair
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Joanne Hunt
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Benyu Jiang
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Paul Taylor
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Phil Chowienczyk
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Andrew J Webb
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK.
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Fok H, Guilcher A, Li Y, Brett S, Shah A, Clapp B, Chowienczyk P. Augmentation pressure is influenced by ventricular contractility/relaxation dynamics: novel mechanism of reduction of pulse pressure by nitrates. Hypertension 2014; 63:1050-5. [PMID: 24516104 DOI: 10.1161/hypertensionaha.113.02955] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Augmentation pressure (AP), the increment in aortic pressure above its first systolic shoulder, is thought to be determined mainly by pressure wave reflection but could be influenced by ventricular ejection characteristics. We sought to determine the mechanism by which AP is selectively reduced by nitroglycerin (NTG). Simultaneous measurements of aortic pressure and flow were made at the time of cardiac catheterization in 30 subjects (11 women; age, 61±13 years [mean±SD]) to perform wave intensity analysis and calculate forward and backward components of AP generated by the ventricle and arterial tree, respectively. Measurements were made at baseline and after NTG given systemically (800 μg sublingually, n=20) and locally by intracoronary infusion (1 μg/min; n=10). Systemic NTG had no significant effect on first shoulder pressure but reduced augmentation (and central pulse pressure) by 12.8±3.1 mm Hg (P<0.0001). This resulted from a reduction in forward and backward wave components of AP by 7.0±2.4 and 5.8±1.3 mm Hg, respectively (each P<0.02). NTG had no significant effect on the ratio of amplitudes of either backward/forward waves or backward/forward compression wave energies, suggesting that effects on the backward wave were largely secondary to those on the forward wave. Time to the forward expansion wave was reduced (P<0.05). Intracoronary NTG decreased AP by 8.3±3.6 mm Hg (P<0.05) with no significant effect on the backward wave. NTG reduces AP and central pulse pressure by a mechanism that is, at least in part, independent of arterial reflections and relates to ventricular contraction/relaxation dynamics with enhanced myocardial relaxation.
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Affiliation(s)
- Henry Fok
- Department of Clinical Pharmacology, St Thomas' Hospital, King's College London, Lambeth Palace Rd, London SE1 7EH, United Kingdom.
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Long-term intense resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower central augmentation pressure. J Hypertens 2014; 32:286-93. [DOI: 10.1097/hjh.0000000000000035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Izzo JL. Hemodynamics. Hypertension 2013. [DOI: 10.2217/ebo.12.535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Joseph L Izzo
- Joseph L Izzo Jr is Professor of Medicine, Pharmacology and Toxicology, and Chief of Clinical Pharmacology at the University at Buffalo, State University of New York (SUNY-Buffalo; NY, USA). He is also Clinical Director of Medicine at the Erie County Medical Center, Buffalo (NY, USA). Training includes a MD from Johns Hopkins (MD, USA), an internal medicine residency at Washington University (MO, USA) and a research fellowship in the Hypertension–Endocrine branch of the National Heart, Lung and Blood
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Nichols WW, Harripersaud K, Petersen JW. Nitrates and Arterial Function. CURRENT CARDIOVASCULAR RISK REPORTS 2013. [DOI: 10.1007/s12170-013-0312-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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28
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Wang JJ, Bouwmeester JC, Belenkie I, Shrive NG, Tyberg JV. Alterations in Aortic Wave Reflection With Vasodilation and Vasoconstriction in Anaesthetized Dogs. Can J Cardiol 2013; 29:243-53. [DOI: 10.1016/j.cjca.2012.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Revised: 03/11/2012] [Accepted: 03/11/2012] [Indexed: 11/15/2022] Open
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O'Rourke MF, Adji A, Namasivayam M, Mok J. Arterial aging: a review of the pathophysiology and potential for pharmacological intervention. Drugs Aging 2012; 28:779-95. [PMID: 21970306 DOI: 10.2165/11592730-000000000-00000] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This review begins with a perspective on the effects of arterial aging on society and world events over the past century. Until recently, the use of just one technique to measure blood pressure non-invasively limited progress in understanding the mechanisms involved and the potential of antihypertensive drug therapies. New methods for extracting information from the arterial waveform have followed the (re)introduction of arterial tonometry into clinical practice, together with mathematical analysis in the frequency and time domains. These new methods have exposed the phenomenon of aortic stiffening with age, and early wave reflection arising therefrom, and identified it as the major cause of cardiovascular degeneration. Such findings point to arterial aging as a logical target for the treatment and prevention not only of cardiac, aortic and large artery disease, but also of damage to microvessels in the brain and kidney, which in turn leads insidiously to dementia and renal failure, respectively.
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31
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Estimating central SBP from the peripheral pulse: influence of waveform analysis and calibration error. J Hypertens 2011; 29:1357-66. [PMID: 21558956 DOI: 10.1097/hjh.0b013e3283479070] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare estimation of central cSBP by application of a generalized transfer function (GTF) to a peripheral arterial waveform and from the late systolic shoulder (SBP(2)) of such a waveform and assess errors introduced by noninvasive calibration of the waveform. METHODS The digital arterial pulse was acquired noninvasively with a servo-controlled finger cuff. A high fidelity pressure tipped catheter was placed in the proximal aortic root. Measurements were made at baseline (n = 40), after nitrovasodilation, handgrip exercise (n = 18) and during pacing (n = 10). Estimates of cSBP obtained using a GTF and from SBP(2) (using an algorithm applied to individual cardiac cycles) of the digital arterial waveform were compared with values measured at the aortic root. RESULTS When arterial waveforms were calibrated from aortic intra-arterial mean and DBP there was close agreement between estimated and measured cSBP: mean difference between estimated and measured cSBP (SD): 1.0 (5.7) and -0.7 (5.5) mmHg for GTF and SBP(2), respectively. Noninvasive oscillometric calibration increased variability in estimation of cSBP [mean difference, 1.3 (11) mmHg for SBP(2)] but estimates of the cSBP to peripheral systolic pressure increment from oscillometric calibration of SBP(2) agreed well with those obtained using invasive calibration [mean difference -2.4 (6.1) mmHg]. CONCLUSION SBP(2) potentially provides a simple measure of cSBP and is of comparable accuracy to a GTF. Noninvasive calibration increases variability for both methods but has less effect on the cSBP to peripheral SBP increment.
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Adji A, O'Rourke MF, Namasivayam M. Arterial stiffness, its assessment, prognostic value, and implications for treatment. Am J Hypertens 2011; 24:5-17. [PMID: 20940710 DOI: 10.1038/ajh.2010.192] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Arterial stiffness has been known as a sign of cardiovascular risk since the 19th century. Despite this, accurate measurement and clinical utility have only emerged in recent times. Arterial stiffness and its hemodynamic consequences are now established as predictors of adverse cardiovascular outcome. They are easily and reliably measured using a range of noninvasive techniques, which can be used readily by risk assessment facilities or individual practitioners. The techniques described in this review are based on the pulsatility of the cardiovascular system, utilizing the timing of pulse travel along major arteries and the magnitude of wave reflection. These have enabled better understanding of the ill effects of arterial stiffening, not only on large arteries and the left ventricle, but also on tiny arteries in highly perfused organs such as brain and kidneys. Treatment options, which directly target the consequences of arterial stiffening, as opposed to arbitrary reduction of brachial blood pressure, have proved clinical superiority; optimal therapy entails use of angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, and calcium-channel blockers, as well as vasodilating β-blockers. Arterial stiffness will undoubtedly contribute to cardiovascular assessment and management in future clinical practice. Reviews such as this will hopefully increase awareness of the mounting evidence underlying this transition, and the relevant theory and methodology. As we begin the second decade of the 21st century, we are finally collectively coming to realize what pioneers such as Osler, Roy, Bramwell and Hill foresaw in the 19th and 20th centuries.
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O'Rourke MF, Safar ME, Dzau V. The Cardiovascular Continuum extended: Aging effects on the aorta and microvasculature. Vasc Med 2010; 15:461-8. [DOI: 10.1177/1358863x10382946] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The ‘Cardiovascular Continuum’ was described by Dzau and colleagues in 2006 to explain the development over many years of coronary disease with its complications, then end-stage heart failure. The Continuum identified different points along the way where the process could be interrupted by drug therapies or interventions, then described the trials that have been undertaken over the last three decades to establish their value. The approach summarized the major steps in cardiology through modern times, but it had an emphasis on coronary atherosclerosis in prosperous nations, and did not account fully for the problems of aging, which occur in all societies. Aging of the aorta and elastic arteries causes arterial stiffening and leads to development of cardiac failure and microvascular disease in highly perfused organs such as the brain and kidneys. The ‘Vascular Aging Continuum’ which we introduce, dovetails with the late phases of the Cardiovascular Continuum and provides a more comprehensive explanation, especially for vascular diseases in nations with little atherosclerosis. It will become more common in the Western World where attention to risk factors and widespread use of statins are responsible for a decrease in atherosclerotic disease, prolongation of life, and dominance of macrovascular and microvascular arterial disease, as well as of cardiac failure.
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Affiliation(s)
- Michael F O'Rourke
- St Vincent's Clinic, Victor Chang Cardiac Research Institute and University of New South Wales, Sydney, Australia,
| | - Michel E Safar
- Paris Descartes University, Hospital Hotel-Dieu, Diagnosis Center, Paris, France
| | - Victor Dzau
- Duke University Medical Centre, Duke University, Durham, NC, USA
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Miyashita H, Aizawa A, Hashimoto J, Hirooka Y, Imai Y, Kawano Y, Kohara K, Sunagawa K, Suzuki H, Tabara Y, Takazawa K, Takenaka T, Yasuda H, Shimada K. Cross-sectional characterization of all classes of antihypertensives in terms of central blood pressure in Japanese hypertensive patients. Am J Hypertens 2010; 23:260-8. [PMID: 20044738 DOI: 10.1038/ajh.2009.255] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Central blood pressure (CBP) has been reported to be superior to brachial blood pressure (BP) as a cardiovascular risk predictor in hypertensive patients; however, the effects of antihypertensives on CBP have not been fully examined. This cross-sectional hypothesis-generating study aimed to tentatively characterize all classes of antihypertensives in relation to CBP. METHODS Calibrated tonometric radial artery pressure waveforms were recorded using an automated device in 1,727 treated hypertensive patients and 848 nonhypertensive (non-HT) participants. Radial artery late systolic BP (SBP) has been reported to reflect central SBP. The difference between late and peak SBPs (DeltaSBP2) was assessed with linear regression model-based adjustments. Separate regression models for DeltaSBP2 were constructed for both participant groups as well as specified sub-populations. RESULTS DeltaSBP2 was 3.3 mm Hg lower in patients treated with any single-vasodilating (VD) antihypertensive agent without significant interclass difference than with non-VD agents, and was 2.0 mm Hg lower than estimated in nonhypertensive subjects. Combinations of two vasodilators were 6.6 and 2.9 mm Hg lower in DeltaSBP2 than nonvasodilator combinations and nonhypertensive subjects, respectively (P < 0.001 for all comparisons). Nonvasodilators and their combination showed high DeltaSBP2, 1.1 and 3.7 mm Hg higher than in nonhypertensive subjects (P < 0.001 for both). Additional adjustment of the pulse rate reduced high DeltaSBP2 with beta-blockers (betaBLs). CONCLUSIONS This cross-sectional observation suggests that vasodilatory antihypertensives lower CBP independently of peripheral BP levels without evident class-specific differences, whereas nonvasodilators may raise CBP.
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Oral L-citrulline supplementation attenuates blood pressure response to cold pressor test in young men. Am J Hypertens 2010; 23:12-6. [PMID: 19851298 DOI: 10.1038/ajh.2009.195] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Oral L-citrulline is efficiently converted to L-arginine, which has been shown to decrease brachial blood pressure (BP) at rest and during the cold pressor test (CPT). However, aortic BP may better reflect cardiovascular risk than brachial BP. The purpose of this study was to test the hypothesis that oral L-citrulline supplementation attenuates brachial BP and aortic hemodynamic responses to CPT. METHODS Brachial BP, aortic BP, stroke volume (SV), and wave reflection at rest and during CPT were evaluated in 17 young (21.6 +/- 0.9 years) normotensive men. Subjects were randomly assigned to 4 weeks of oral L-citrulline (6 g/day) or placebo in a crossover design. Hemodynamic responses to CPT were reevaluated after each treatment. RESULTS During CPT, there were significant (P < 0.05) increases in brachial and aortic BP [systolic (SBP), diastolic (DBP), and pulse pressure (PP)], augmentation index (AIx), SV, and a decrease in transit time of the reflected wave (Tr) from baseline. Compared to placebo, oral L-citrulline treatment decreased (P < 0.05) brachial SBP (-6 +/- 11 mm Hg), aortic SBP (-4 +/- 10 mm Hg), and aortic PP (-3 +/- 6 mm Hg) during CPT but not at rest. There was an inverse correlation (r = -0.40, P < 0.05) between changes in aortic SBP and Tr during CPT after L-citrulline supplementation. CONCLUSIONS We conclude that oral L-citrulline supplementation attenuates the brachial SBP, aortic SBP, and aortic PP responses to CPT in young normotensive men. Increased wave reflection time contributes to the reduction in aortic SBP response to CPT.
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Cecelja M, Jiang B, McNeill K, Kato B, Ritter J, Spector T, Chowienczyk P. Increased wave reflection rather than central arterial stiffness is the main determinant of raised pulse pressure in women and relates to mismatch in arterial dimensions: a twin study. J Am Coll Cardiol 2009; 54:695-703. [PMID: 19679247 DOI: 10.1016/j.jacc.2009.04.068] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 04/06/2009] [Accepted: 04/14/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVES Our aim was to examine the relative contributions of the first systolic shoulder (P1) and augmentation pressure (DeltaP(aug)) to central pulse pressure (cPP), their relation to central arterial stiffness (pulse wave velocity [PWV]) and arterial diameters, and their respective heritability estimates. BACKGROUND cPP is augmented above P1 by DeltaP(aug) due to pressure waves reflected from the periphery of the circulation. METHODS Women (n = 496) from the Twins UK adult twin registry (112 monozygotic, 135 dizygotic pairs) age 21 to 81 years were studied. cPP, P1, and DeltaP(aug) were estimated using the SphygmoCor system (Atcor, West Ryde, Australia) from transformed radial waveforms. Carotid-femoral PWV was measured using the same system. Aortic and femoral artery diameters were measured by ultrasonography. Heritability was estimated using structural equation modeling. RESULTS P1 and DeltaP(aug) accounted for 22% and 76%, respectively, of the variance in cPP. After adjustment for mean arterial pressure and heart rate, P1 strongly independently positively correlated with PWV (standardized regression coefficient, beta = 0.4, p < 0.0001), whereas DeltaP(aug) did not independently correlate with PWV but independently negatively correlated with the ratio of the diameter of the femoral to that of the abdominal aorta (beta = -0.12, p < 0.001). Estimates of heritability (h(2)) of cPP, PWV, P1, and DeltaP(aug) were 0.43, 0.34, 0.31, and 0.62, respectively, after adjustment for mean arterial pressure and heart rate. CONCLUSIONS These results suggest that, in women, DeltaP(aug) is highly heritable, is associated with the ratio of distal to proximal arterial diameters, and, independent of PWV, is a major determinant of cPP.
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Affiliation(s)
- Marina Cecelja
- King's College London, Cardiovascular Division, London, UK
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Graham MR, Evans P, Davies B, Baker JS. Arterial pulse wave velocity, inflammatory markers, pathological GH and IGF states, cardiovascular and cerebrovascular disease. Vasc Health Risk Manag 2009; 4:1361-71. [PMID: 19337549 PMCID: PMC2663454 DOI: 10.2147/vhrm.s3220] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Blood pressure (BP) measurements provide information regarding risk factors associated with cardiovascular disease, but only in a specific artery. Arterial stiffness (AS) can be determined by measurement of arterial pulse wave velocity (APWV). Separate from any role as a surrogate marker, AS is an important determinant of pulse pressure, left ventricular function and coronary artery perfusion pressure. Proximal elastic arteries and peripheral muscular arteries respond differently to aging and to medication. Endogenous human growth hormone (hGH), secreted by the anterior pituitary, peaks during early adulthood, declining at 14% per decade. Levels of insulin-like growth factor-I (IGF-I) are at their peak during late adolescence and decline throughout adulthood, mirror imaging GH. Arterial endothelial dysfunction, an accepted cause of increased APWV in GH deficiency (GHD) is reversed by recombinant human (rh) GH therapy, favorably influencing the risk for atherogenesis. APWV is a noninvasive method for measuring atherosclerotic and hypertensive vascular changes increases with age and atherosclerosis leading to increased systolic blood pressure and increased left ventricular hypertrophy. Aerobic exercise training increases arterial compliance and reduces systolic blood pressure. Whole body arterial compliance is lowered in strength-trained individuals. Homocysteine and C-reactive protein are two inflammatory markers directly linked with arterial endothelial dysfunction. Reviews of GH in the somatopause have not been favorable and side effects of treatment have marred its use except in classical GHD. Is it possible that we should be assessing the combined effects of therapy with rhGH and rhIGF-I? Only multiple intervention studies will provide the answer.
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Affiliation(s)
- Michael R Graham
- Health and Exercise Science Research Unit, Faculty of Health Sport and Science, University of Glamorgan, Pontypridd, Wales, United Kingdom.
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Abstract
The subject of arterial stiffness as a modifiable risk factor is controversial and difficult to understand. The best approach here will be to assist readers to understand the issue and the basis of controversy. We also hope to show that the subject is not as overwhelming as it might appear. We believe that new blood is required in this field and that a basic understanding is necessary for researchers to be induced to take on such investigations. Our approach sets out a historic and pathophysiologic background on which modern studies can be based; describes measures and indices of arterial stiffness including pulse wave velocity, augmentation index, ambulatory arterial stiffness index, aortic impedance, and carotid elastic modulus; and finally, addresses the specifics of this interesting and important question. Although aortic stiffening with age is attributable to fracture of elastin lamellae and is largely irreversible, stiffening of muscular arteries can be modified by vasodilator drugs, and by improved endothelial function such as induced by exercise training.
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Munir S, Jiang B, Guilcher A, Brett S, Redwood S, Marber M, Chowienczyk P. Exercise reduces arterial pressure augmentation through vasodilation of muscular arteries in humans. Am J Physiol Heart Circ Physiol 2008; 294:H1645-50. [DOI: 10.1152/ajpheart.01171.2007] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Exercise markedly influences pulse wave morphology, but the mechanism is unknown. We investigated whether effects of exercise on the arterial pulse result from alterations in stroke volume or pulse wave velocity (PWV)/large artery stiffness or reduction of pressure wave reflection. Healthy subjects ( n = 25) performed bicycle ergometry. with workload increasing from 25 to 150 W for 12 min. Digital arterial pressure waveforms were recorded using a servo-controlled finger cuff. Radial arterial pressure waveforms and carotid-femoral PWV were determined by applanation tonometry. Stroke volume was measured by echocardiography, and brachial and femoral artery blood flows and diameters were measured by ultrasound. Digital waveforms were recorded continuously. Other measurements were made before and after exercise. Exercise markedly reduced late systolic and diastolic augmentation of the peripheral pressure pulse. At 15 min into recovery, stroke volume and PWV were similar to baseline values, but changes in pulse wave morphology persisted. Late systolic augmentation index (radial pulse) was reduced from 54 ± 3.9% at baseline to 42 ± 3.7% ( P < 0.01), and diastolic augmentation index (radial pulse) was reduced from 37 ± 1.8% to 25 ± 2.9% ( P < 0.001). These changes were accompanied by an increase in femoral blood flow (from 409 ± 44 to 773 ± 48 ml/min, P < 0.05) and an increase in femoral artery diameter (from 8.2 ± 0.4 to 8.6 ± 0.4 mm, P < 0.05). In conclusion, exercise dilates muscular arteries and reduces arterial pressure augmentation, an effect that will enhance ventricular-vascular coupling and reduce load on the left ventricle.
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Abstract
Approximately 5 million people in the United States have heart failure. Epidemiologic studies have demonstrated that at least one half of patients who have clinically overt heart failure have diastolic heart failure (DHF), or heart failure with preserved ejection fraction. DHF is characterized by concentric remodeling with normal left ventricular end-diastolic volume, abnormalities of active relaxation, and increased passive ventricular stiffness. Diuretics are an essential component of therapy for most patients who have DHF, and treatment of hypertension is a cornerstone of therapy designed to prevent or to treat DHF. Several antihypertensive agents have been shown to effectively reduce wave reflection, including angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, calcium antagonists, and nitrates. Lifestyle changes may also be helpful.
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Affiliation(s)
- Dinko Susic
- Ochsner Clinic Foundation, New Orleans, LA 70121, USA
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Jiang XJ, O'Rourke MF, Zhang YQ, He XY, Liu LS. Superior effect of an angiotensin-converting enzyme inhibitor over a diuretic for reducing aortic systolic pressure. J Hypertens 2007; 25:1095-9. [PMID: 17414675 DOI: 10.1097/hjh.0b013e3280ac1533] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND In recent studies, benefit has been shown for angiotensin-converting enzyme (ACE) inhibitors and calcium antagonists over a beta-blocker in hypertension, through a greater reduction in aortic than brachial systolic and pulse pressure. No data are available on diuretics, even though these are the preferred initial treatment of patients with mild hypertension. METHODS In this study, 101 patients with mild essential hypertension were randomly assigned to an 8-week period of monotherapy with enalapril 10 mg a day or indapamide 2.5 mg a day. Central as well as brachial systolic, augmented, and pulse pressure were determined using SphygmoCor, as in the REASON and CAFE trials. RESULTS Enalapril and indapamide reduced brachial systolic, diastolic, mean and pulse pressure to the same extent, and the heart rate was unchanged. Although there was no difference in brachial pressure with enalapril and indapamide, enalapril caused a greater fall in estimated aortic systolic, and pulse pressures. The augmentation index, an index of wave reflection, fell from 33.7 to 28.3% with enalapril but was unchanged with indapamide. CONCLUSION Results infer a reduction in wave reflection with enalapril, causing a fall in aortic pressure augmentation, and a corresponding fall in aortic systolic and pulse pressure. These were not apparent from brachial cuff measurements. Results show that a diuretic, like a beta-blocker agent, is not as effective a therapy as an ACE inhibitor in reducing aortic systolic and pulse pressure, and that the difference is not attributable to a change in heart rate.
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Affiliation(s)
- Xiong-Jing Jiang
- Division of Hypertension, Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China
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O'Rourke MF, Hashimoto J. Mechanical factors in arterial aging: a clinical perspective. J Am Coll Cardiol 2007; 50:1-13. [PMID: 17601538 DOI: 10.1016/j.jacc.2006.12.050] [Citation(s) in RCA: 811] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2006] [Revised: 12/08/2006] [Accepted: 12/10/2006] [Indexed: 02/06/2023]
Abstract
The human arterial system in youth is beautifully designed for its role of receiving spurts of blood from the left ventricle and distributing this as steady flow through peripheral capillaries. Central to such design is "tuning" of the heart to arterial tree; this minimizes aortic pressure fluctuations and confines flow pulsations to the larger arteries. With aging, repetitive pulsations (some 30 million/year) cause fatigue and fracture of elastin lamellae of central arteries, causing them to stiffen (and dilate), so that reflections return earlier to the heart; in consequence, aortic systolic pressure rises, diastolic pressure falls, and pulsations of flow extend further into smaller vessels of vasodilated organs (notably the brain and kidney). Stiffening leads to increased left ventricular (LV) load with hypertrophy, decreased capacity for myocardial perfusion, and increased stresses on small arterial vessels, particularly of brain and kidney. Clinical manifestations are a result of diastolic LV dysfunction with dyspnea, predisposition to angina, and heart failure, and small vessel degeneration in brain and kidney with intellectual deterioration and renal failure. While aortic stiffening is the principal cause of cardiovascular disease with age in persons who escape atherosclerotic complications, it is not a specific target for therapy. The principal target is the smooth muscle in distributing arteries, whose relaxation has little effect on peripheral resistance but causes substantial reduction in the magnitude of wave reflection. Such relaxation is achieved through regular exercise and with the vasodilating drugs that are used in modern treatment of hypertension and cardiac failure.
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Prior JC, Nielsen JD, Hitchcock CL, Williams LA, Vigna YM, Dean CB. What is the role of non-invasive measurements of atherosclerosis in individual cardiovascular risk prediction? Clin Sci (Lond) 2007; 112:517-25. [PMID: 17419685 DOI: 10.1042/cs20060266] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Primary prevention of CVD (cardiovascular disease) is mainly based on the assessment of individual cardiovascular risk factors. However, often, only the most important (conventional) cardiovascular risk factors are determined, and every level of risk factor exposure is associated with a substantial variation in the amount of atherosclerosis. Measuring the effect of risk factor exposure over time directly in the vessel might (partially) overcome these shortcomings. Several non-invasive imaging techniques have the potential to accomplish this, each of these techniques focusing on a different stage of the atherosclerotic process. In this review, we aim to define the current role of various of these non-invasive measurements of atherosclerosis in individual cardiovascular risk prediction, taking into account the most recent insights about validity and reproducibility of these techniques and the results of recent prospective outcome trials. We conclude that, although the clinical application of FMD (flow-mediated dilation) and PWA (pulse wave analysis) in individual cardiovascular risk prediction seems far away, there may be a role for PWV (pulse wave velocity) and IMT (intima-media thickness) measurements in the near future.
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Affiliation(s)
- Jerilynn C Prior
- Centre for Menstrual Cycle and Ovulation Research, Division of Endocrinology and Metabolism, Department of Medicine, University of British Columbia and Vancouver Coastal Health Research Institute, Vancouver, BC, Canada.
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Chung AWY, Au Yeung K, Cortes SF, Sandor GGS, Judge DP, Dietz HC, van Breemen C. Endothelial dysfunction and compromised eNOS/Akt signaling in the thoracic aorta during the progression of Marfan syndrome. Br J Pharmacol 2007; 150:1075-83. [PMID: 17339838 PMCID: PMC2013910 DOI: 10.1038/sj.bjp.0707181] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND AND PURPOSE Aortic complications account for the major mortality in Marfan syndrome (MFS), a connective tissue disorder caused by mutations in FBN1 encoding fibrillin-1. We hypothesized that MFS impaired endothelial function and nitric oxide (NO) production in the aorta. EXPERIMENTAL APPROACH Mice (at 3, 6, 9 and 12 months of age) heterozygous for the Fbn1 allele encoding a cysteine substitution (Fbn1 (C1039G/+), Marfan mice, n=75), the most common class of mutation in MFS, were compared with age-matched control littermates (n=75). Thoracic and abdominal aortas from the two groups were studied. KEY RESULTS Isometric force measurements revealed that relaxation to ACh (but not to sodium nitroprusside) was diminished in the phenylephrine-precontracted Marfan thoracic aorta at 6 months of age (pEC(50)=6.12+/-0.22; maximal response, E(max)=52.7+/-6.8%; control: pEC(50)=7.34+/-0.19; E(max)=84.8+/-2.2%). At one year, both inhibition of NO production with N(omega)-nitro-L-arginine methyl ester, or denudation of endothelium increased the phenylephrine-stimulated contraction in the control thoracic aorta by 35%, but had no effect in the Marfan aorta, indicating a loss of basal NO production in the Marfan vessel. From 6 months, a reduced phosphorylation of endothelial NOS (eNOS)(Ser1177) and Akt(Thr308) detected by Western blotting was observed in the Marfan thoracic aorta, which was accompanied by decreased levels of cGMP. Expressions of Akt and eNOS in the abdominal aorta were not different between the two groups. CONCLUSIONS AND IMPLICATIONS MFS impairs endothelial function and signaling of NO production in the thoracic aorta, suggesting the importance of NO in the age-related progression of thoracic aortic manifestations.
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MESH Headings
- Acetylcholine/pharmacology
- Age Factors
- Animals
- Aorta, Abdominal/metabolism
- Aorta, Abdominal/physiopathology
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiopathology
- Calcium/metabolism
- Cyclic GMP/metabolism
- Disease Models, Animal
- Disease Progression
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Enzyme Inhibitors/pharmacology
- Fibrillin-1
- Fibrillins
- Marfan Syndrome/metabolism
- Marfan Syndrome/physiopathology
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Microfilament Proteins/genetics
- Microfilament Proteins/metabolism
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide/metabolism
- Nitric Oxide Synthase Type II/antagonists & inhibitors
- Nitric Oxide Synthase Type II/metabolism
- Nitric Oxide Synthase Type III
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- Signal Transduction/drug effects
- Vasodilation/drug effects
- Vasodilator Agents/pharmacology
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Affiliation(s)
- A W Y Chung
- Child and Family Research Institute and Departments of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, BC, Canada.
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Sakurai M, Yamakado T, Kurachi H, Kato T, Kuroda K, Ishisu R, Okamoto S, Isaka N, Nakano T, Ito M. The relationship between aortic augmentation index and pulse wave velocity: an invasive study. J Hypertens 2007; 25:391-7. [PMID: 17211246 DOI: 10.1097/hjh.0b013e3280115b7c] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The aortic augmentation index (AI) and aortic pulse wave velocity (PWV) are known to be indicators of arterial stiffness. However, it is not clear whether aortic AI and PWV reflect aortic stiffness in similar ways. We investigated the relationship between aortic AI and PWV by measuring them directly using a catheter technique. DESIGN AND METHODS Forty-one patients, aged 34-79 years, were studied during diagnostic cardiac catheterization. Aortic pressures were measured using a catheter-tip manometer at two points, one in the ascending aorta and one 40 cm distally in the descending aorta. Aortic AI was defined as the difference between early and late pressure peaks divided by the pulse pressure of the ascending aorta. Aortic PWV was calculated as the distance between the two measuring sites divided by the transit time. We also examined the effects of vasodilatation on AI and PWV by the intra-aortic administration of nitroglycerin in 15 patients. RESULTS AI was significantly related to age, systolic aortic pressure, heart rate, left ventricular ejection time, and height. Aortic PWV showed an association only with age and systolic aortic pressure. There was no significant relationship between aortic AI and PWV (r = 0.28, NS). Nitroglycerin also produced different effects on aortic AI and PWV: aortic AI was significantly decreased (-0.17, P < 0.01) after nitroglycerin, but PWV remained unchanged (+0.4 m/s, NS). CONCLUSIONS Aortic AI and PWV cannot be used interchangeably as an index of arterial stiffness. AI may not be a true indicator of arterial stiffness, but an index of wave reflection including PWV.
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Affiliation(s)
- Masato Sakurai
- Department of Cardiology, Mie University of Medicine, Mie, Japan
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Protogerou AD, Papaioannou TG, Blacher J, Papamichael CM, Lekakis JP, Safar ME. Central blood pressures: do we need them in the management of cardiovascular disease? Is it a feasible therapeutic target? J Hypertens 2007; 25:265-72. [PMID: 17211229 DOI: 10.1097/hjh.0b013e3280114f23] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
It is well established that in young and healthy individuals central (aortic or carotid) systolic and pulse pressures are different from peripheral (brachial) corresponding pressures as a consequence of progressive changes in arterial stiffness and pressure wave reflections along the arterial tree. There is evidence indicating that in interventions with pharmaceutical and non-pharmaceutical agents, central pressures are subjected to greater changes than peripheral pressures, and they are more closely related to the pathophysiology of end-organ damage or cardiovascular risk. Therefore central blood pressures may be of higher clinical importance than peripheral pressures. The present review aims to provide an insight into the (patho)physiology of central blood pressures, to present the most accurate techniques for their estimation, and to discuss the available experimental and epidemiological data that support the emerging need for the evaluation of central blood pressures in clinical practice.
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O'Rourke MF, Nichols WW. Potential for use of pulse wave analysis in determining the interaction between sildenafil and glyceryl trinitrate. Clin Cardiol 2006; 25:295-9. [PMID: 12058794 PMCID: PMC6654350 DOI: 10.1002/clc.4960250611] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND The early part of the central aortic pressure pulse, with amplitude (PI - Pd), is generated by left ventricular ejection, while the latter part (or augmented pressure), with amplitude (Ps - Pi), is generated by the reflected wave arriving during systole. The effects of arterial vasodilator agents, especially nitrates, on central aortic systolic blood pressure are grossly underestimated by sphygmomanometric measurements of brachial artery pressure. HYPOTHESIS The objective of this study was to investigate the potential for use of central arterial pulse wave analysis, obtained noninvasively from the radial pulse, in determining the interaction between sildenafil and the nitric oxide donor drug glyceryl trinitrate (GTN). METHODS Central aortic pressure waveforms were generated from noninvasively measured radial artery pressure wave-forms and subjected to pulse wave analysis to determine the interaction between sildenafil and transdermally applied GTN. RESULTS Transdermal GTN (2.5, 5.0, and 15 mg per 24-h patches) alone caused no consistent change in sphygmomanometer-determined systolic or diastolic pressures, but there was a consistent, dose-related fall in amplitude of the augmented systolic pressure, (Ps - Pi), of 4.0, 7.0, and 11 mmHg, respectively, with little change in diastolic pressure. The 2.5 mg patch caused a fall of 4.0 mmHg in aortic systolic pressure, while augmentation index (AIx) fell from 20 to 11% and pulse pressure fell 18%. When oral sildenafil (50 mg) was administered after GTN (2.5 mg), aortic systolic pressure fell another 4.0 mmHg. This decrease in systolic pressure caused a fall in AIx to almost 0.0%; pulse pressure fell another 9.0%. CONCLUSION These modifications in aortic systolic and pulse pressure are due primarily to reduction in wave-reflection amplitude and are not detected by sphygmomanometer-measured brachial artery pressure.
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Affiliation(s)
- Michael F O'Rourke
- Department of Medicine, St Vincent's Hospital, University of New South Wales, Sydney, Australia.
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Söderqvist E, Hultman J, Källner G, Nowak J, Brodin LA. The assessment of acute load and contractility changes by left ventricular pressure measurements. Physiol Meas 2006; 27:1281-92. [PMID: 17135700 DOI: 10.1088/0967-3334/27/12/003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this study was to establish whether analysis of the left ventricular pressure waveform provides indicative information about cardiac load and contractility and to develop an algorithm for computer-based assessment of changes in these variables. In eight healthy standard breed anaesthetized open-chest pigs, a high frequency response guide-wire mounted pressure sensor was introduced into the left ventricle. Preload reduction was induced by vena cava occlusion, afterload increase by an i.v. injection of phenylephrine and increased contractility by an i.v. injection of adrenalin. Left ventricular pressure waveform analysis was performed by plotting the slope of the pressure curve during the systolic ejection period versus maximal systolic pressure. The analysis revealed characteristic changes in left ventricular pressure and pressure waveform and identified easily discernible reaction patterns in the slope versus maximal pressure plot, specific for each provocation. Analysis of the left ventricular waveform provides indicative information about loading conditions and contractility. The proposed algorithm can easily be implemented in pressure monitoring systems allowing real-time assessment and discrimination of acute changes in preload, afterload and myocardial performance.
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Affiliation(s)
- Emil Söderqvist
- Department of Medical Engineering, Karolinska Institutet, Stockholm, Sweden.
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Stewart AD, Jiang B, Millasseau SC, Ritter JM, Chowienczyk PJ. Acute Reduction of Blood Pressure by Nitroglycerin Does Not Normalize Large Artery Stiffness in Essential Hypertension. Hypertension 2006; 48:404-10. [PMID: 16908758 DOI: 10.1161/01.hyp.0000237669.64066.c5] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Stiffness of large elastic arteries is elevated in subjects with hypertension, an effect that could potentially be explained by increased distending pressure. We examined effects of an acute change in blood pressure on carotid-femoral pulse wave velocity and carotid artery distensibility (inversely related to stiffness) in normotensive control subjects (n=20, mean age 42) with mean arterial pressure (MAP) 84+/-1.7 mm Hg (mean+/-SE) and subjects with essential hypertension (n=20, mean age 45, MAP 104+/-2.0 mm Hg). Normotensive subjects received intravenous nitroglycerin (NTG) and angiotensin II to lower/increase blood pressure. Hypertensive subjects received NTG to lower blood pressure. Pulse wave velocity was 24% (95% CI: 12% to 35%) higher and carotid distensibility 47% (95% CI: 32% to 63%) lower in hypertensive subjects compared with controls. In normotensive subjects, acute changes in blood pressure produced expected changes in stiffness. However, in hypertensive subjects, despite reducing MAP by 22 mm Hg to the same level as in normotensive subjects, there was no detectable reduction in arterial stiffness: pulse wave velocity remained 24% (95% CI: 10% to 38%) higher and carotid distensibility 48% (95% CI: 31% to 63%) lower in hypertensive compared with normotensive subjects. Because blood pressure-independent effects of NTG are, if anything, to reduce stiffness, these results indicate that elevated carotid and aortic stiffness in hypertensive subjects is not explained by elevated blood pressure but relates to structural change in the arterial wall.
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Affiliation(s)
- Andrew D Stewart
- Cardiovascular Division, King's College London School of Medicine, St Thomas' Hospital, London, United Kingdom
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50
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Quick CM, Berger DS, Stewart RH, Laine GA, Hartley CJ, Noordergraaf A. Resolving the hemodynamic inverse problem. IEEE Trans Biomed Eng 2006; 53:361-8. [PMID: 16532762 DOI: 10.1109/tbme.2005.869664] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The "hemodynamic inverse problem" is the determination of arterial system properties from pressures and flows measured at the entrance of an arterial system. Conventionally, investigators fit reduced arterial system models to data, and the resulting model parameters represent putative arterial properties. However, no unique solution to the inverse problem exists-an infinite number of arterial system topologies result in the same input impedance (Zin) and, therefore, the same pressure and flow. Nevertheless, there are exceptions to this theoretical limitation; total peripheral resistance (Rtot), total arterial compliance (Ctot), and characteristic impedance (ZO) can be uniquely determined from input pressure and flow. Zin is determined completely by Ctot and Rtot at low frequencies, Zo at high frequencies, and arterial topology and reflection effects at intermediate frequencies. We present a novel method to determine the relative contribution of Zo, Ctot, Rtot and arterial topology/reflection to Zin without assuming a particular reduced model. This method is tested with a large-scale distributed model of the arterial system, and is applied to illustrative cases of measured pressure and flow. This work, thus, lays the theoretical foundation for determining the arterial properties responsible for increased pulse pressure with age and various arterial system pathologies.
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Affiliation(s)
- Christopher M Quick
- Michael E. DeBakey Institute, Department of Physiology and Pharmacology, Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-4466, USA.
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