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Avesani M, Jalal Z, Friedberg MK, Villemain O, Venet M, Di Salvo G, Thambo JB, Iriart X. Adverse remodelling in tetralogy of Fallot: From risk factors to imaging analysis and future perspectives. Hellenic J Cardiol 2024; 75:48-59. [PMID: 37495104 DOI: 10.1016/j.hjc.2023.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 05/29/2023] [Accepted: 07/21/2023] [Indexed: 07/28/2023] Open
Abstract
Although contemporary outcomes of initial surgical repair of tetralogy of Fallot (TOF) are excellent, the survival of adult patients remains significantly lower than that of the normal population due to the high incidence of heart failure, ventricular arrhythmias, and sudden cardiac death. The underlying mechanisms are only partially understood but involve an adverse biventricular response, so-called remodelling, to key stressors such as right ventricular (RV) pressure-and/or volume-overload, myocardial fibrosis, and electro-mechanical dyssynchrony. In this review, we explore risk factors and mechanisms of biventricular remodelling, from histological to electro-mechanical aspects, and the role of imaging in their assessment. We discuss unsolved challenges and future directions to better understand and treat the long-term sequelae of this complex congenital heart disease.
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Affiliation(s)
- Martina Avesani
- Paediatric and Congenital Cardiology Department, M3C National Reference Centre, Bordeaux University Hospital, Bordeaux, France; IHU Liryc, Electrophysiology and Heart Modelling Institute, Bordeaux University Foundation, Pessac, France; Paediatric Cardiology Unit, Department of Woman's and Child's Health, University-Hospital of Padova, University of Padua, Padua, Italy
| | - Zakaria Jalal
- Paediatric and Congenital Cardiology Department, M3C National Reference Centre, Bordeaux University Hospital, Bordeaux, France; IHU Liryc, Electrophysiology and Heart Modelling Institute, Bordeaux University Foundation, Pessac, France
| | - Mark K Friedberg
- Labatt Family Heart Center, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Olivier Villemain
- Labatt Family Heart Center, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Maeyls Venet
- Labatt Family Heart Center, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Giovanni Di Salvo
- Paediatric Cardiology Unit, Department of Woman's and Child's Health, University-Hospital of Padova, University of Padua, Padua, Italy
| | - Jean-Benoît Thambo
- Paediatric and Congenital Cardiology Department, M3C National Reference Centre, Bordeaux University Hospital, Bordeaux, France; IHU Liryc, Electrophysiology and Heart Modelling Institute, Bordeaux University Foundation, Pessac, France
| | - Xavier Iriart
- Paediatric and Congenital Cardiology Department, M3C National Reference Centre, Bordeaux University Hospital, Bordeaux, France; IHU Liryc, Electrophysiology and Heart Modelling Institute, Bordeaux University Foundation, Pessac, France.
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Rogers DP, Marazia S, Chow AW, Lambiase PD, Lowe MD, Frenneaux M, McKenna WJ, Elliott PM. Effect of biventricular pacing on symptoms and cardiac remodelling in patients with end-stage hypertrophic cardiomyopathy. Eur J Heart Fail 2014; 10:507-13. [DOI: 10.1016/j.ejheart.2008.03.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 12/27/2007] [Accepted: 03/12/2008] [Indexed: 11/25/2022] Open
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Burchell AE, Sobotka PA, Hart EC, Nightingale AK, Dunlap ME. Chemohypersensitivity and autonomic modulation of venous capacitance in the pathophysiology of acute decompensated heart failure. Curr Heart Fail Rep 2013; 10:139-46. [PMID: 23504401 DOI: 10.1007/s11897-013-0135-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Heart failure is increasing in prevalence around the world, with hospitalization and re-hospitalization as a result of acute decompensated heart failure (ADHF) presenting a huge social and economic burden. The mechanism for this decompensation is not clear. Whilst in some cases it is due to volume expansion, over half of patients with an acute admission for ADHF did not experience an increase in total body weight. This calls into question the current treatment strategy of targeting salt and water retention in ADHF. An alternative hypothesis proposed by Fallick et al. is that an endogenous fluid shift from the splanchnic bed is implicated in ADHF, rather than an exogenous fluid gain. The hypothesis states further that this shift is triggered by an increase in sympathetic tone causing vasoconstriction in the splanchnic bed, a mechanism that can translocate blood rapidly into the effective circulating volume, generating the raised venous pressure and congestion seen in ADHF. This hypothesis encourages a new clinical paradigm which focuses on the underlying mechanisms of congestion, and highlights the importance of fluid redistribution and neurohormonal activation in its pathophysiology. In this article, we consider the concept that ADHF is attributable to episodic sympathetic hyperactivity, resulting in fluid shifts from the splanchnic bed. Chemosensitivity is a pathologic autonomic mechanism associated with mortality in patients with systolic heart failure. Tonic and episodic activity of the peripheral chemoreceptors may underlie the syndrome of acute decompensation without total body salt and water expansion. We suggest in this manuscript that chemosensitivity in response to intermittent hypoxia, such as experienced in sleep disordered breathing, may explain the intermittent sympathetic hyperactivity underlying renal sodium retention and acute volume redistribution from venous storage sites. This hypothesis provides an alternative structure to guide novel diagnostic and treatment strategies for ADHF.
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Affiliation(s)
- Amy E Burchell
- Bristol CardioNomics Group, Bristol Heart Institute, Bristol Royal Infirmary, Bristol, BS2 8HW, UK
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Abstract
A lumped parameter model of the cardiovascular system has been developed and optimized using experimental data obtained from 13 healthy subjects during graded head-up tilt (HUT) from the supine position to . The model includes descriptions of the left and right heart, direct ventricular interaction through the septum and pericardium, the systemic and pulmonary circulations, nonlinear pressure volume relationship of the lower body compartment, arterial and cardiopulmonary baroreceptors, as well as autoregulatory mechanisms. A number of important features, including the separate effects of arterial and cardiopulmonary baroreflexes, and autoregulation in the lower body, as well as diastolic ventricular interaction through the pericardium have been included and tested for their significance. Furthermore, the individual effect of parameter associated with heart failure, including LV and RV contractility, baseline systemic vascular resistance, pulmonary vascular resistance, total blood volume, LV diastolic stiffness and reflex gain on HUT response have also been investigated. Our fitted model compares favorably with our experimental measurements and published literature at a range of tilt angles, in terms of both global and regional hemodynamic variables. Compared to the normal condition, a simulated congestive heart failure condition produced a blunted response to HUT with regards to the percentage changes in cardiac output, stroke volume, end diastolic volume and effector response (i.e., heart contractility, venous unstressed volume, systemic vascular resistance and heart rate) with progressive tilting.
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Schwarz K, Singh S, Dawson D, Frenneaux MP. Right ventricular function in left ventricular disease: pathophysiology and implications. Heart Lung Circ 2013; 22:507-11. [PMID: 23587560 DOI: 10.1016/j.hlc.2013.03.072] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 03/17/2013] [Indexed: 12/01/2022]
Abstract
The functions of the left and right ventricles are intimately linked. The right ventricle (RV) has transverse muscle fibres in its free wall and also shares oblique fibres in the interventricular septum with the left ventricle (LV). The latter constitute a link between left and right ventricular contractile function such that LV contraction augments RV contraction - a phenomenon called systolic ventricular interaction. When RV afterload is increased (by raised pulmonary artery pressure) overall contractile performance becomes increasingly dependent on this systolic ventricular interaction because the oblique septal fibres are more mechanically efficient than the free wall transverse fibres in conditions of high RV afterload. When LV end diastolic pressure is increased by heart failure due to LV systolic dysfunction, pulmonary artery pressure becomes raised, imposing an increased afterload on the RV. In such patients global LV performance is reduced, consequently systolic ventricular interaction is reduced resulting in a reduction in RV contractile performance even if the RV is not directly involved in the disease process causing LV systolic dysfunction. Furthermore, as the left ventricle becomes progressively more spherical the septal fibres become less oblique, dramatically reducing their mechanical advantage and further impairing RV contractile function. This ultimately leads to clinical right ventricular failure. This in turn typically results in tricuspid regurgitation and a vicious cycle of right ventricular enlargement with further reduction in the oblique nature of the septal fibres. In addition to the systolic interaction of the LV on the RV, when the RV is enlarged and stretches the pericardium, pericardial and right ventricular diastolic pressures may become markedly increased and this can result in constraint to filling of the LV by the pericardium (pericardial constraint) and by the RV via the interventricular septum (diastolic ventricular interaction).
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Notarius CF, Morris BL, Floras JS. Dissociation between reflex sympathetic and forearm vascular responses to lower body negative pressure in heart failure patients with coronary artery disease. Am J Physiol Heart Circ Physiol 2009; 297:H1760-6. [PMID: 19734366 DOI: 10.1152/ajpheart.00012.2009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Many heart failure (HF) patients exhibit paradoxical forearm vasodilation when central blood volume is reduced by lower body negative pressure (LBNP). We tested the hypothesis that this response results from reflex sympathetic withdrawal. We recorded simultaneously forearm blood flow, muscle sympathetic nerve activity (MSNA), and plasma norepinephrine (PNE) during four random applications of LBNP, -5, -10, -20, and -40 mmHg, in 12 men with HF (mean left ventricular ejection fraction = 24 + or - 2%) and 10 healthy, normal, age-matched men (N). Compared with N, MSNA burst frequency (P = 0.001) and PNE (P = 0.005) were significantly higher in the HF group, both at rest and during LBNP. As anticipated in N, LBNP -40 mmHg significantly increased MSNA (+14.2 + or - 2.5 bursts/min; P < 0.05) and PNE (+0.83 + or - 0.22 nmol/l; P < 0.05) and decreased forearm vascular conductance (FVC) (-11.7 + or - 3.2 ml.min(-1).mmHg(-1); P < 0.05). In the HF group, LBNP elicited similar increases in MSNA (+11.5 + or - 2.0; P < 0.05) and PNE (+0.85 + or - 0.12; P < 0.05), without affecting FVC significantly (-4.1 + or - 2.4; P = 0.01 vs. N, interaction P = 0.03). However, within the HF group, responses were bimodal: LBNP -40 mmHg increased MSNA in all subjects (P < 0.001), yet the six patients with nonischemic or dilated cardiomyopathy (DCM) exhibited significant vasoconstriction (decrease in FVC; P = 0.001), whereas the six patients with ischemic cardiomyopathy (ICM) exhibited significant vasodilation (increase in FVC; P < 0.02 vs. DCM and N; interaction P = 0.02). Cold pressor testing increased MSNA and decreased FVC in ICM (n = 4). Thus paradoxical forearm vasodilator responses to LBNP in HF are not mediated by reflex sympathetic withdrawal. ICM and DCM patients differ qualitatively in their vascular responses to hypotensive LBNP.
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Affiliation(s)
- Catherine F Notarius
- Division of Cardiology, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
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Zervan K, Male C, Benesch T, Salzer-Muhar U. Ventricular interaction in children after repair of tetralogy of Fallot: a longitudinal echocardiographic study. EUROPEAN JOURNAL OF ECHOCARDIOGRAPHY 2009; 10:641-6. [DOI: 10.1093/ejechocard/jep025] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Petersson M, Friberg P, Lambert G, Rundqvist B. Decreased renal sympathetic activity in response to cardiac unloading with nitroglycerin in patients with heart failure*. Eur J Heart Fail 2007; 7:1003-10. [PMID: 16227138 DOI: 10.1016/j.ejheart.2004.11.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2004] [Revised: 09/16/2004] [Accepted: 11/11/2004] [Indexed: 11/19/2022] Open
Abstract
AIMS To examine changes in renal sympathetic outflow in response to cardiac unloading with nitroglycerin (GTN) in patients with chronic heart failure (CHF) and healthy subjects (HS). METHODS AND RESULTS Renal (RNAsp) and total body (TBNAsp) noradrenaline (NA) spillover were measured with radiotracer methods in 16 patients with CHF (50+/-3 years, LVEF 20+/-1%) and nine HS (57+/-2 years) during right heart and renal vein catheterisation. Low dose GTN decreased mean pulmonary artery pressure (PAm: CHF -7+/-2 mm Hg, HS -4+/-1 mm Hg, p<0.05 vs. baseline) but not mean arterial pressure (MAP: CHF -2+/-1 mm Hg, HS -2+/-1 mm Hg) and did not affect RNAsp in any of the study groups. High dose GTN lowered MAP (CHF -12+/-1 mm Hg, HS -12+/-2 mm Hg, p<0.05 vs. baseline) and PAm (CHF -13+/-2 mm Hg, HS -5+/-1 mm Hg, p<0.05 vs. baseline) and was accompanied by a significant reduction in RNAsp only in CHF (1.3+/-0.1 nmol/min baseline to 0.9+/-0.2 nmol/min, p<0.05), whereas RNAsp in HS remained unchanged. CONCLUSIONS In spite of a reduction in both arterial pressure and cardiac filling pressures, renal sympathetic activity decreased in CHF and did not increase in HS. These findings suggest that the altered loading conditions resulting from high-dose GTN infusion have renal sympathoinhibitory effects.
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Affiliation(s)
- Magnus Petersson
- Department of Cardiology, The Cardiovascular Institute, Sahlgrenska University Hospital, S-413 45 Göteborg, Sweden.
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Wilson LD, Wan X, Rosenbaum DS. Cellular alternans: a mechanism linking calcium cycling proteins to cardiac arrhythmogenesis. Ann N Y Acad Sci 2007; 1080:216-34. [PMID: 17132786 DOI: 10.1196/annals.1380.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Essentially all previous research on alternans has been restricted to normal myocardium, whereas sudden cardiac death (SCD) occurs most commonly in patients with ventricular dysfunction (i.e., heart failure), which is associated with marked disruption of proteins responsible for normal calcium cycling in myocytes. Several lines of evidence from studies in normal hearts suggest a link between impaired calcium cycling which characterizes ventricular mechanical dysfunction and impaired calcium cycling that is responsible for alternans. In normal myocardium, cells which exhibit the slowest calcium cycling, and not the slowest repolarization, are most susceptible to alternans. Decreased expression of key calcium cycling proteins is observed in alternans-prone cells. Sarcoplasmic reticulum ATPase (SERCA2a) expression is decreased, suggesting a mechanism for the slower sarcoplasmic reticulum (SR) calcium reuptake observed in alternans-prone cells. In addition, diminished ryanodine receptor (RyR) function leading to abnormal calcium release from the SR is also linked to cellular alternans. Although impaired contractile function clearly predisposes to SCD, the mechanisms linking mechanical to electrophysiological dysfunction in the heart are unclear. We propose that cellular calcium alternans may be an important mechanism linking mechanical dysfunction to cardiac arrhythmogenesis.
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Affiliation(s)
- Lance D Wilson
- MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Hamann 330, Cleveland, OH 44109-1998, USA
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Wernicke D, Wessel N, Malberg H, Plehm R, Bauernschmitt R, Thierfelder L. Autonomic cardiac control in animal models of cardiovascular diseases II. Variability analysis in transgenic rats with α-tropomyosin mutations Asp175Asn and Glu180Gly. BIOMED ENG-BIOMED TE 2007; 52:50-5. [PMID: 17313334 DOI: 10.1515/bmt.2007.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Animal models of cardiovascular diseases allow to investigate relevant pathogenetic mechanisms in detail. In the present study, the mutations Asp175Asn and Glu180Gly in alpha-tropomyosin (TPM1), known cause familiar hypertrophic cardiomyopathy (FHC) were studied for changes in hemodynamic parameters and spontaneous baroreflex regulation in transgenic rats in comparison to transgenic and non-transgenic controls by telemetry. Heart rate variability (HRV) and blood pressure variability (BPV) were analyzed using time- and frequency domain, as well as non-linear measures. The dual sequence method was used for the estimation of the baroreflex regulation. In transgenic rats harboring mutated TPM1, changes in HRV were detected during exercise, but not at rest. Both mutations, Asp175Asn and Glu180Gly, caused increased low frequency power. In addition, in animals with mutation Asp175Asn a reduced total HRV was observed. BPV did not show any differences between all transgenic animal lines. During exercise, a strong increase in the number of bradycardic and tachycardic fluctuations accompanied with decreased baroreflex sensitivity (BRS) was detected in animals with either TPM1 mutation, Asp175Asn or Glu180Gly. These data suggest, that the analysis of cardiac autonomic control, particularly of baroreflex regulation, represents a powerful non-invasive approach to investigate the effects of subtle changes in sarcomeric architecture on cardiac physiology in vivo. In case of mutations Asp175Asn or Glu180Gly in TPM1, early detection of alterations in autonomic cardiac control could help to prevent sudden cardiac death in affected persons.
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Affiliation(s)
- Dirk Wernicke
- Max Delbrück Center for Molecular Medicine, Berlin, Germany.
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Piccirillo G, Magrì D, di Carlo S, De Laurentis T, Torrini A, Matera S, Magnanti M, Bernardi L, Barillà F, Quaglione R, Ettorre E, Marigliano V. Influence of cardiac-resynchronization therapy on heart rate and blood pressure variability: 1-year follow-up. Eur J Heart Fail 2006; 8:716-22. [PMID: 16513420 DOI: 10.1016/j.ejheart.2006.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Revised: 11/14/2005] [Accepted: 01/18/2006] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Several studies have shown that cardiac-resynchronization therapy (CRT) improves haemodynamic function, cardiac symptoms, and heart rate variability (HRV) and reduces the risk of mortality and sudden death in subjects with chronic heart failure (CHF). In subjects with CHF, power spectral values for the low-frequency (LF) component of RR variability < or =13 ms2, are associated with an increased risk of sudden death. AIMS AND METHODS To assess whether spectral indexes obtained by power spectral analysis of HRV and systolic blood pressure (SBP) variability could predict malignant ventricular arrhythmias in patients with severe CHF treated with an implantable cardioverter-defibrillator (ICD) alone or with ICD+CRT. In addition, changes in non-invasive spectral indices using short-term power spectral analysis of HRV and SBP variability during controlled breathing in 15 patients with CHF treated with an ICD alone and 16 patients receiving ICD+CRT, were assessed pre-treatment and at 1 year. RESULTS Arrhythmias necessitating an appropriate ICD shock were more frequent in subjects who had low LF power. CRT improved all spectral components, including LF power. CONCLUSIONS Low LF power values predict an increased risk of malignant ventricular arrhythmias; after 1 year of CRT most non-spectral and spectral data, including LF power, improved. Whether these improvements lead to better long-term survival in patients with CHF remains unclear.
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Affiliation(s)
- Gianfranco Piccirillo
- Dipartimento di Scienze dell'Invecchiamento, I Clinica Medica, Policlinico Umberto I, Università La Sapienza, 00161 Rome, Italy.
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Al-Hesayen A, Floras JS, Parker JD. The effects of intravenous sildenafil on hemodynamics and cardiac sympathetic activity in chronic human heart failure. Eur J Heart Fail 2006; 8:864-8. [PMID: 16829186 DOI: 10.1016/j.ejheart.2006.03.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Revised: 02/07/2006] [Accepted: 03/29/2006] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Erectile dysfunction is common in patients with chronic heart failure and sildenafil is an effective treatment option in this population. Sildenafil has been reported to increase sympathetic outflow in normal volunteers. To date, experience with sildenafil in patients with congestive heart failure is limited and the impact of phosphodiesterase-5 inhibition on sympathetic activity in this population has not been evaluated. METHODS AND RESULTS 10 patients with heart failure (ejection fraction 23+/-3%) were studied. Generalized and cardiac sympathetic activity responses to an intravenous infusion of sildenafil were measured by the norepinephrine spillover method. In response to sildenafil, there was a significant reduction in mean pulmonary artery (-26+/-5%, P<0.01) and mean arterial pressures (-8+/-1%, P<0.01). These hemodynamic responses were accompanied by a 22+/-5% reduction in cardiac norepinephrine spillover (P<0.02) but no change in total body norepinephrine spillover. CONCLUSIONS The acute administration of sildenafil is associated with a modest reduction in systemic arterial blood pressure and a more substantial reduction in pulmonary arterial pressure. These hemodynamic changes are observed in the absence of systemic sympathetic activation and are associated with a reduction in cardiac norepinephrine spillover in patients with chronic heart failure. These observations are relevant given the high prevalence of erectile dysfunction in this patient population.
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Affiliation(s)
- Abdul Al-Hesayen
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital and University Health Network, University of Toronto, Ontario, Canada M5G 1X5
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Williams L, Frenneaux M. Diastolic ventricular interaction: from physiology to clinical practice. ACTA ACUST UNITED AC 2006; 3:368-76. [PMID: 16810172 DOI: 10.1038/ncpcardio0584] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Accepted: 03/30/2006] [Indexed: 11/08/2022]
Abstract
The ventricles share a common septum and, therefore, the filling of one influences the compliance of the other. This phenomenon is known as direct diastolic ventricular interaction. The interaction is noticeably increased when the force exerted by the surrounding pericardium is raised, which is termed pericardial constraint. In healthy individuals, pericardial constraint is minor in the resting state. When right ventricular volume-to-pressure ratio acutely increases, however, such as during exercise, massive pulmonary embolism, or right ventricular infarction, notable diastolic ventricular interaction occurs. In this setting, the measured left ventricular intracavitary diastolic pressure overestimates the true left ventricular filling pressure, because the effect of external forces must be subtracted. Although growth of the pericardium can be a feature of chronic cardiac enlargement, here we review the evidence of the importance of diastolic ventricular interaction in certain acute and chronic disease processes, including heart failure.
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Affiliation(s)
- Lynne Williams
- Department of Cardiovascular Medicine, University of Birmingham, Birmingham, UK.
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Strickberger SA, Benson DW, Biaggioni I, Callans DJ, Cohen MI, Ellenbogen KA, Epstein AE, Friedman P, Goldberger J, Heidenreich PA, Klein GJ, Knight BP, Morillo CA, Myerburg RJ, Sila CA. AHA/ACCF scientific statement on the evaluation of syncope: from the American Heart Association Councils on Clinical Cardiology, Cardiovascular Nursing, Cardiovascular Disease in the Young, and Stroke, and the Quality of Care and Outcomes Research Interdisciplinary Working Group; and the American College of Cardiology Foundation In Collaboration With the Heart Rhythm Society. J Am Coll Cardiol 2006; 47:473-84. [PMID: 16412888 DOI: 10.1016/j.jacc.2005.12.019] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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de Carvalho FC, Consolim-Colombo FM, Pastore CA, Rubira MC, Menegüetti JC, Krieger EM, Wajngarten M. Acute reduction of ventricular volume decreases QT interval dispersion in elderly subjects with and without heart failure. Am J Physiol Heart Circ Physiol 2005; 288:H2171-6. [PMID: 15626693 DOI: 10.1152/ajpheart.00427.2004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To evaluate the effects of acute reduction in ventricular volume (VV) on QT interval dispersion (QTd), 14 men with heart failure (HF; 74.5 ± 2 yr of age) and 11 healthy male control subjects (68 ± 2 yr of age) were studied. For 15 min, lower body negative pressure (LBNP) was applied at −15 and −40 mmHg to reduce venous return. At baseline and during LBNP application, QTd was measured with an 87-lead, body-surface-mapping device; chamber volumes were assessed by radioisotope ventriculography; blood pressure (BP) and heart rate (HR) were continuously monitored; and blood samples were obtained for assessment of norepinephrine (Nor) levels. At −15 mmHg, LNBP application induced a significant decrease in VV but did not change BP and HR in both groups. In addition, Nor levels increased significantly ( P ≤ 0.05) in the control group (from 286.7 ± 31.5 to 388.8 ± 41.2 pg/ml) and in HF patients (from 405.8 ± 56 to 477.6 ± 47 pg/ml), and QTd was significantly ( P ≤ 0.05) decreased in the control group (57.2 ± 3.8 vs. 49.1 ± 3.4 ms) and in HF patients (67.8 ± 6 vs. 63.7 ± 5.9 ms). No additional decreases in VV or QTd were produced by −40 mmHg LNBP, but Nor levels did increase in both groups and reach 475.5 ± 34 and 586.5 ± 60 pg/ml ( P < 0.05) in the control and HF groups, respectively; BP did not change, but HR also increased in both groups. In conclusion, an acute LBNP-induced reduction in VV caused a decrease in the QTd of elderly men regardless of the existence of HF. Because increased sympathetic activity with more intense LBNP was not accompanied by additional changes in QTd, altered QTd may be better related to changes in VV than to autonomic nervous system activity.
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Schmitt M, Blackman DJ, Middleton GW, Cockcroft JR, Frenneaux MP. Assessment of venous capacitance. Radionuclide plethysmography: methodology and research applications. Br J Clin Pharmacol 2002; 54:565-76. [PMID: 12492602 PMCID: PMC1874491 DOI: 10.1046/j.1365-2125.2002.t01-7-01689.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Matthias Schmitt
- Department of Cardiology, Wales Heart Research Institute, University of Wales College of Medicine, Cardiff, UK.
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Abstract
Because the ventricles share a common septum, the filling of one may influence the compliance of the other, a phenomenon known as direct diastolic ventricular interaction (DVI). This interaction is markedly enhanced when the force exerted by the surrounding pericardium is raised (pericardial constraint). In health, in the resting state, we operate near the top of the flat component of a J-shaped pericardial stress-strain relation. Therefore, pericardial constraint (and hence DVI) is only minor. When right ventricular volume/pressure acutely increases, such as during exercise, massive pulmonary embolism, or right ventricular infarction, pericardial constraint increases and significant DVI develops. In this setting, the measured left ventricular intracavitary diastolic pressure markedly overestimates the true left ventricular filling pressure, because the external forces must be subtracted. Although the pericardium can grow during chronic cardiac enlargement, we present evidence that in certain chronic disease processes, including heart failure, DVI may also be important.
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Affiliation(s)
- J A Morris-Thurgood
- Department of Cardiology, Wales Heart Research Institute, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
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Guazzi M, Maltagliati A, Tamborini G, Celeste F, Pepi M, Muratori M, Berti M, Guazzi MD. How the left and right sides of the heart, as well as pulmonary venous drainage, adapt to an increasing degree of head-up tilting in hypertrophic cardiomyopathy: differences from the normal heart. J Am Coll Cardiol 2000; 36:185-93. [PMID: 10898433 DOI: 10.1016/s0735-1097(00)00698-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVES We aimed to assess the differences in the adaptive response of patients with hypertrophic cardiomyopathy (HCM) compared with normal subjects, as well as any association with increased susceptibility to the test. BACKGROUND Diastolic function contributes importantly in the adaptation of the normal heart to head-up tilting. This mechanism may be disturbed by an impaired relaxation in HCM. METHODS Twenty-one male patients with HCM (46 +/- 6 years old) and 22 healthy men (44 +/- 8 years) were studied using Doppler echocardiography after 1 and 10 min of head-up tilting at 20 degrees, 40 degrees and 60 degrees. RESULTS In control subjects, tilting was associated with 1) a predominance of diastolic pulmonary venous flow and early left ventricular (LV) filling (atrium functioning as an open conduit); 2) right ventricular (RV) shrinkage; and 3) no LV dimensional variations. In patients with HCM, tilting was associated with 1) a prevalence of systolic pulmonary venous flow (atrium functioning as a reservoir in which filling depends on atrial relaxation and compliance) and late diastolic transmitral flow (atrium working as a booster pump); 2) LV shrinkage; and 3) no RV dimension variations. These mechanisms did not prevent stroke volume (SV) from decreasing at 40 degrees and 60 degrees in both groups. Because of a lower increase in heart rate (HR), a reduction in cardiac output (CO) was greater in patients with HCM. The responses were similar after 1 and 10 min of tilting in control subjects, whereas in patients, blood pressure (BP), SV and LV dimension fell more after 10 min. CONCLUSIONS Adaptation of the normal heart to tilting is based on a ventricular interaction and LV diastolic properties; HCM relies on left atrial diastolic and systolic functions. An inadequate HR reaction to a fall in BP and SV in HCM (depressed reflexogenic activity) contributes to making CO more vulnerable by greater and more prolonged displacements.
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Affiliation(s)
- M Guazzi
- Istituto di Cardiologia dell'Università degli Studi, Centro Cardiologico, IRCCS, Centro di Studio Ricerche Cardiovascolari del Consiglio Nazionale delle Ricerche, Milano, Italy.
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Atherton JJ, Dryburgh LG, Thomson HL, Moore TD, Wright KN, Muehle GW, Fitzpatrick LE, Frenneaux MP. Forearm vasoconstriction during dynamic leg exercise in patients with chronic heart failure. Heart Vessels 2000; 13:278-89. [PMID: 10651170 DOI: 10.1007/bf03257232] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous studies assessing vascular responses in nonexercising beds during exercise in patients with chronic heart failure (CHF) have yielded varying results. We proposed that the clinical and hemodynamic severity of heart failure may explain some of the variation. We reasoned that diastolic ventricular interaction (DVI), by limiting the ability of such patients to increase left ventricular (LV) volume and stroke volume during exercise, would attenuate baroreflex activation, resulting in increased sympathetic activation and hence exaggerated vasoconstriction. We hypothesized therefore that vasoconstriction in nonexercising beds would be exaggerated in patients with symptomatic and hemodynamically severe heart failure, particularly if associated with DVI. We measured forearm vascular resistance (FVR) during semierect cycle exercise in 22 CHF patients and 23 control subjects. DVI was assessed by measuring changes in ventricular volumes (radionuclide ventriculography) during volume unloading (-30 mm Hg lower-body negative pressure) in the heart failure patients and was inferred when LV end-diastolic volume paradoxically increased. Patients with symptoms of heart failure developed larger increases in FVR during exercise than did asymptomatic patients. There were significant correlations between the change in FVR during peak exercise and the resting mean pulmonary arterial pressure and pulmonary vascular resistance. CHF patients with DVI developed exaggerated increases in FVR (median [25th to 75th percentile]) compared with the remaining patients during low-workload exercise (138 [66 to 171] vs 6.4 [-4.3 to 28] units, P = 0.002) and during peak exercise (160 [90 to 384] vs 61 [-7.4 to 75] units, P < 0.02). Vasoconstriction in nonexercising beds is exaggerated in CHF patients with clinically and hemodynamically severe heart failure, particularly if associated with DVI. This may explain some of the reported variation in the degree of sympathetic activation that occurs during exercise in CHF patients.
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Affiliation(s)
- J J Atherton
- Department of Medicine, University of Queensland, Brisbane, Australia
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21
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Atherton JJ, Blackman DJ, Moore TD, Bachmann AW, Tunny TJ, Thomson HL, Gordon RD, Frenneaux MP. Diastolic ventricular interaction in chronic heart failure: relation to heart rate variability and neurohumoral status. Heart Vessels 2000; 13:269-77. [PMID: 10651169 DOI: 10.1007/bf03257231] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
It is likely that abnormal baroreflex control mechanisms are at least partially responsible for autonomic dysfunction in chronic heart failure. We recently demonstrated that diastolic ventricular interaction is associated with impaired baroreflex control of vascular resistance in heart failure. We reasoned that by constraining left ventricular filling, such interaction would decrease baroreflex activity and, thereby, increase sympathetic and decrease parasympathetic outflow. We hypothesized, therefore, that diastolic ventricular interaction in chronic heart failure patients would be associated with autonomic dysfunction. We used radionuclide ventriculography to measure changes in left and right ventricular end-diastolic volumes during acute volume unloading achieved by -30 mm Hg lower-body negative pressure in 30 patients with chronic heart failure. An increase in left ventricular volume in association with a reduction in right ventricular volume indicates diastolic ventricular interaction (a larger increase indicating a greater degree of interaction). We also measured heart rate variability (n = 23) and resting venous plasma norepinephrine (n = 24), epinephrine (n = 24), and atrial natriuretic peptide (ANP) (n = 14). During lower-body negative pressure, while right ventricular volume decreased in all patients (P < 0.001), left ventricular end-diastolic volume increased (from 152 +/- 25 to 157 +/- 36 ml/m2, P = 0.01). The change in left ventricular volume was positively correlated with resting plasma norepinephrine (P < 0.01) and ANP (P < 0.005), and negatively correlated with the standard deviation of normal to normal R-R intervals (P < 0.005), the root-mean-square of differences between successive normal to normal R-R intervals (P < 0.05), total power (P < 0.01), low-frequency power (P < 0.01), and high-frequency power (P < 0.05). Diastolic ventricular interaction in patients with chronic heart failure is associated with sympathetic nervous system activation evidenced by increased plasma norepinephrine and reduced heart rate variability.
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Affiliation(s)
- J J Atherton
- Department of Medicine, University of Queensland, Brisbane, Australia
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22
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Galatius S, Wroblewski H, Sørensen VB, Bie P, Arendrup H, Kastrup J. Calf blood flow during prolonged tilt in idiopathic dilated cardiomyopathy and after cardiac transplantation. Am J Physiol Heart Circ Physiol 2000; 278:H239-48. [PMID: 10644604 DOI: 10.1152/ajpheart.2000.278.1.h239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In severe congestive heart failure (CHF), abnormal reflex control of calf blood flow during brief head-up tilt that appears to normalize after transplantation (HTX) may be present during prolonged observation also. Therefore, we studied the effect of prolonged (30 min) 50 degrees head-up tilt on calf skeletal muscle blood flow measured by the local (133)Xe washout method in CHF and after HTX and in patients with the presence vs. absence of native right atrium (+PNA and -PNA, respectively). During brief head-up tilt, skeletal muscle blood flow increased 13 +/- 42% in 9 severe CHF patients in contrast to a -28 +/- 22% decrease (P < 0.01) in 11 control subjects, -24 +/- 30% decrease in 15 moderate CHF patients (P < 0.05), -25 +/- 14% decrease in 12 patients with recent HTX (P < 0.01), and -21 +/- 24% decrease in 8 patients with distant HTX (P = 0.06). However, during sustained tilt, blood flow declined to similar levels of that in the other groups in severe CHF. HTX -PNA vs. +PNA showed blunted skeletal muscle vasomotor control (P < 0.05) and a higher systolic blood pressure (139 +/- 14 vs. 125 +/- 15 mmHg, P < 0.05) and heart rate (92 +/- 10 vs. 83 +/- 8 beats/min, P < 0.05). Thus paradox vasodilatation of calf skeletal muscle in severe CHF is present only during brief but not prolonged tilt. This may be one explanation of the rare presence of orthostatic intolerance in CHF and implies only a minor possible role for the abnormality in edema pathogenesis. Removal of all right atrium in HTX has an important hemodynamic impact that may possibly affect later clinical outcome.
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Affiliation(s)
- S Galatius
- The Heart Center, The Rigshospital, DK-2100 Copenhagen, Denmark.
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Azevedo ER, Newton GE, Parker AB, Floras JS, Parker JD. Sympathetic responses to atrial natriuretic peptide in patients with congestive heart failure. J Cardiovasc Pharmacol 2000; 35:129-35. [PMID: 10630743 DOI: 10.1097/00005344-200001000-00017] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Previous studies have shown that atrial natriuretic peptide (ANP) has relative sympathoinhibitory effects that are of potential benefit in patients with congestive heart failure (CHF). In this study, cardiac and systemic sympathetic responses to ANP were evaluated and compared with responses to sodium nitroprusside (SNP) in patients with CHF. Right- and left-heart hemodynamics were obtained simultaneously with cardiac (CANESP) and total body (TBNESP) norepinephrine spillover; these were measured by using the radiotracer technique. Reductions in arterial blood pressure and cardiac filling pressures were similar with both drugs. ANP and SNP caused a significant and similar increase in TBNESP. Mean values for CANESP did not change in either group, but the response of individual patients was dependent on the effect on diastolic blood pressure (r = -0.71, p<0.01). These results do not provide evidence for a sympathoinhibitory effect of ANP, but suggest that in patients with CHF, cardiac sympathoexcitatory response to arterial baroreceptor unloading may be countered by a potential sympathoinhibitory effect caused by a reduction in cardiac filling pressures. In the setting of CHF, vasodilator therapy may decrease cardiac sympathetic activity if systemic hypotension is avoided.
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Affiliation(s)
- E R Azevedo
- Department of Medicine, Mount Sinai Hospital, University of Toronto, Ontario, Canada
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Atherton JJ, Frenneaux MP, Thomson HL. The role of diastolic ventricular interaction in abnormal cardiac baroreflex function in chronic heart failure. AUSTRALIAN AND NEW ZEALAND JOURNAL OF MEDICINE 1999; 29:428-32. [PMID: 10868515 DOI: 10.1111/j.1445-5994.1999.tb00738.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Baroreflex abnormalities have been well documented in both patients with chronic heart failure and experimental animal models of heart failure. These abnormalities are associated with increased mortality and probably contribute to neurohumoral activation. While it is likely that several mechanisms contribute to reduced baroreflex sensitivity, it has been difficult to explain why baroreflex control mechanisms during acute volume unloading in patients with severe chronic heart failure should be directionally opposite to those in normal subjects. Volume unloading normally causes a reduction in baroreceptor activity, and hence an increase in sympathetic outflow; however, patients with chronic heart failure develop attenuated increases or paradoxical reductions in forearm vascular resistance, muscle sympathetic nerve activity, and noradrenaline spillover. It has been suggested that this probably represents paradoxical activation of left ventricular (LV) mechanoreceptors, but why LV receptors should behave in such a fashion has not been determined. In the setting of diastolic ventricular interaction, the filling of the left ventricle is constrained by the surrounding pericardium and right ventricle. In these patients, the reduction in right ventricular (RV) volume that normally occurs during acute volume unloading allows for an increase in LV end-diastolic volume (as opposed to the reduction in LV volume that normally occurs). We have demonstrated this to be important in some patients with chronic heart failure, and observed that baroreflex control of forearm vascular resistance was markedly impaired in these patients. We propose that the increase in LV volume that occurred during volume unloading would increase LV mechanoreceptor activity, and could therefore explain the paradoxical reductions in sympathetic outflow. As discussed, this has important therapeutic implications.
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Affiliation(s)
- J J Atherton
- Department of Cardiology, University of Wales College of Medicine, Heath Park, Cardiff, UK
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Thomson HL, Morris-Thurgood J, Atherton J, Frenneaux M. Reduced cardiopulmonary baroreflex sensitivity in patients with hypertrophic cardiomyopathy. J Am Coll Cardiol 1998; 31:1377-82. [PMID: 9581737 DOI: 10.1016/s0735-1097(98)00102-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES We sought to assess baroreflex function in patients with hypertrophic cardiomyopathy (HCM). BACKGROUND We have previously demonstrated a specific abnormality in the afferent limb of the cardiopulmonary baroreflex in patients with vasovagal syncope. Patients with HCM exhibit abnormal control of their vasculature during exercise and upright tilt; we therefore hypothesize a similar abnormality in the afferent limb of the cardiopulmonary baroreflex arc. METHODS We investigated 29 patients with HCM and 32 control subjects. Integrated baroreceptor sensitivity was assessed after administration of phenylephrine. Cardiopulmonary baroreceptor sensitivity was assessed by measuring forearm vascular resistance (FVR) during lower body negative pressure (LBNP). Carotid artery baroreflex sensitivity was assessed by measuring the in RR interval during manipulation of carotid artery transmural pressure. The integrity of the efferent limb of the reflex arc was determined by studying responses to both handgrip and peripheral alpha-receptor sensitivity. RESULTS During LBNP, FVR increased by only 2.36+/-9 U in patients, compared with an increase of 123+/-8.76 U in control subjects (p=0.001). FVR paradoxically fell in eight patients, but in none of the control subjects. Furthermore, FVR fell by 4.9+/-5.6 U in patients with a history of syncope, compared with an increase of 4.7+/-7.2 U in those without syncope (p=0.014). Integrated and carotid artery baroreflex sensitivities were similar in patients and control subjects (14+/-7 vs. 14+/-6 ms/mm Hg, p=NS and -3+/-2 vs. -4+/-2 ms/mm Hg, p=NS, respectively). Similarly, handgrip responses and the dose/response ratio to phenylephrine were not significantly different. CONCLUSIONS This study suggests that patients with HCM have a defect in the afferent limb of the cardiopulmonary reflex arc.
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Affiliation(s)
- H L Thomson
- Department of Medicine, University of Queensland
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