Relation between coronary artery disease, aortic stiffness, and left ventricular structure in a population sample

Ascending Aorta 4D Time to Peak Distention Sexual Dimorphism and Association with Coronary Plaque Burden Severity in Women

Coronary artery disease (CAD) risk and plaque scores are often subjective and biased, particularly in mid-age asymptomatic women, whose CAD risk assessment has been historically underestimated. In this study, a new automatic ascending aorta time-to-peak-distention (TPD) analysis was developed for fast screening and as an independent surrogate for subclinical atherosclerosis in asymptomatic women. CCTA was obtained in 50 asymptomatic adults. Plaque burden segment involvement score (SIS) and automatic TPD were obtained from all subjects. Logistic regression analyses were performed to investigate the association between CAD risk scores and TPD with severe coronary plaque burden (SIS>5). TPD, individually, was found to be a significant predictor of SIS>5. Additionally, sex was a significant effect modifier of TPD, with a stronger statistically significant association with women. Four-dimensional aortic time-to-peak distention could supplement conventional CCTA analysis and offer a quick objective screening tool for plaque burden severity and CAD risk stratification, especially in women.

Computation of Vascular Parameters: Implementing Methodology and Performance Analysis

This paper presents the feasibility of automated and accurate in vivo measurements of vascular parameters using an ultrasound sensor. The continuous and non-invasive monitoring of certain parameters, such as pulse wave velocity (PWV), blood pressure (BP), arterial compliance (AC), and stiffness index (SI), is crucial for assessing cardiovascular disorders during surgeries and follow-up procedures. Traditional methods, including cuff-based or invasive catheter techniques, serve as the gold standard for measuring BP, which is then manually used to calculate AC and SI through imaging algorithms. In this context, the Continuous and Non-Invasive Vascular Stiffness and Arterial Compliance Screener (CaNVAS) is developed to provide continuous and non-invasive measurements of these parameters using an ultrasound sensor. By driving 5 MHz (ranging from 2.2 to 10 MHz) acoustic waves through the arterial walls, capturing the reflected echoes, and employing pre-processing techniques, the frequency shift is utilized to calculate PWV. It is observed that PWV measured by CaNVAS correlates exponentially with BP values obtained from the sphygmomanometer (BPMR-120), enabling the computation of instantaneous BP values. The proposed device is validated through measurements conducted on 250 subjects under pre- and post-exercise conditions, demonstrating an accuracy of 95% and an average coefficient of variation of 12.5%. This validates the reliability and precision of CaNVAS in assessing vascular parameters.

Relation of the left ventricular geometric patten to coronary artery disease in hypertensive patients using a 320-detector-row CT scanner

BACKGROUND

It was estimated that about 1.3 billion people were diagnosed to be hypertensive in 2015. All countries consistently show this high prevalence. Ischemic heart disease stands as the most common cause of systolic blood pressure-related deaths per year. Left ventricular hypertrophy determined by echocardiography can predict cardiovascular morbidity and mortality. The question of whether the LV geometric pattern has an additional prognostic value is still not clearly answered. Currently, coronary computed tomography is widely used in clinical practice with a great capability of simultaneous evaluation of the LV mass and the coronary arterial tree. Our study aims to examine the relationship between LV mass and geometry and coronary artery disease using an ECG-gated 320-detector- row CT scanner.

RESULTS

Two hundred ninety-eight hypertensive Egyptian individuals were enrolled in our study, the mean age was 57.5 ± 10.5, and males comprised 76.5% of the study population. The mean LV mass and LV mass index were 193 ± 60 gm and 95.2 ± 27.5 g/m² respectively. One-fifth of the patient had CAD luminal stenosis ≥ 50%. Normal LV geometric pattern was observed in about 37% of the study population. About one-third of the patients showed concentric remodeling. Patients with increased LV mass index represented one-third of the study population with a greater percentage of the concentric hypertrophy pattern than the eccentric hypertrophy pattern. Patients with high CAD-RADS showed statistically significant higher LV mass, LV mass index, and septal wall thickness. Patients with high CAD-RADS showed a greater percentage of concentric and eccentric hypertrophy. The LV geometric pattern was the only independent predictor of the high CAD-RADS. The LV geometric patterns associated with high RADS ordered from the highest to the lowest, were concentric LVH, Eccentric LV, and concentric remodeling.

CONCLUSIONS

LV geometric pattern is the only independent predictor of high CAD-RADS after adjustment for LV mass index and septal wall thickness. Among abnormal LV geometric patterns, concentric hypertrophy stands as the most important predictor of high CAD-RADS.

Lower-limb peripheral arterial disease and amputations in people with diabetes: Risk factors, prognostic value and management

Lower-limb peripheral arterial disease (PAD), is a common manifestation of systemic atherosclerosis, resulting from a partial or complete obstruction of at least one lower-limb arteries. PAD is a major endemic disease with an excess risk of major cardiovascular events and death. It also leads to disability, high rates of lower-limb adverse events and non-traumatic amputation. In patients with diabetes, PAD is particularly frequent and has a worse prognosis than in patients without diabetes. The risk factors of PAD are comparable to those for cardiovascular disease. The ankle-brachial index is usually recommended to screen PAD despite its limited performance in patients with diabetes, affected by the presence of peripheral neuropathy, medial arterial calcification, incompressible arteries and infection. Toe brachial index and toe pressure emerge as alternative screening tools. The management of PAD requires strict control of cardiovascular risk factors including diabetes, hypertension and dyslipidaemia, the use of antiplatelet agents and lifestyle management, to reduce cardiovascular adverse events, but few randomized controlled trials have evaluated the benefits of these treatments in PAD. Several advances have been achieved in endovascular and surgical revascularization procedures, with obvious improvement in PAD prognosis. Further studies are required to increase our understanding of the pathophysiology of PAD and to evaluate the interest of different therapeutic strategies in the occurrence and progression of PAD in patients with diabetes. Here, we present a narrative and contemporary review to synthesize the key epidemiology findings, screening and diagnosis methods, and major therapeutic advances regarding PAD in patients with diabetes.

Association of cumulative blood pressure with cardiovascular mortality in Chinese older people: A longitudinal prospective study

OBJECTIVE

Long-term cumulative blood pressure (BP) was associated with cardiovascular mortality in middle-aged to older people. Whether cumulative BP was associated with cardiovascular mortality is uncertain in Chinese older people.

DESIGN

Data were obtained from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a nationwide, ongoing, prospective cohort study of community-dwelling Chinese older people.

SETTING, AND PARTICIPANTS

A total of 3361 older participants from the CLHLS study were included (men: 46.68 %, age: ≥65 years, median age: 78.00 years [IQR: 71.0-86.00 years]).

METHODS

Cumulative BP, including systolic BP (SBP), diastolic BP (DBP) and pulse pressure (PP), was determined by the area under the curve based on three measurements of BP (waves 2008, 2011, and 2014). The outcome was cardiovascular mortality, which was followed from wave 2014 to wave 2018.

RESULTS

During a median follow-up period of 3.98 years, 211 cardiovascular death were recorded. The higher cumulative SBP and PP tended to be positively linearly associated with an elevated risk of cardiovascular mortality. For each SD increment, the adjusted HRs of mortality risk was 1.28 (95 % CI: 1.11-1.47; p = 0.001) and 1.24 (95 % CI, 1.09-1.43; p = 0.002) for cumulative SBP and PP, respectively. While there was no association between cumulative DBP and cardiovascular mortality. In addition, multiple sensitivity analyses suggested robustness of the results.

CONCLUSIONS/IMPLICATIONS

Our results indicate that cumulative SBP and PP were associated with cardiovascular mortality in Chinese older people; however, there was no such association between cumulative DBP and mortality. Therefore, control of long-term SBP and PP may be required in those people.

Brachial pulse pressure is associated with the presence and extent of coronary artery disease in stable angina patients: a cross-sectional study

Background

Previous epidemiological evidence has identified many risk factors for coronary artery disease (CAD). Pulse pressure (PP) was reported to be associated with CAD. However, more attention was paid to aortic PP than to brachial PP. This cross-sectional study aimed to investigate the direct relationship between brachial PP and the presence and extent of CAD in stable angina patients.

Methods

We recruited a total of 1118 consecutive patients with stable chest pain suspected of CAD. After screening with exclusion criteria, 654 patients were finally included in our study. Every patient underwent both blood pressure measurement and selective coronary angiography. Univariate and multivariate analysis were performed to analyze the association between PP and the presence and extent of CAD.

Results

This study revealed that brachial PP was an independent correlate of multivessel CAD. In multivariate generalized linear regression model, increasing brachial PP (per 1 mmHg) were associated with the increased number of diseased vessels (β = 0.01, SE = 0.00, P < 0.0001). Binary logistic regression analysis further confirmed this association. The risk of multivessel CAD increased significantly in patients with brachial PP ≥ 60 mmHg (OR = 1.69, 95% CI = 1.14–2.48, P = 0.0084) and as per 1 mmHg increased in brachial PP (OR = 1.02, 95% CI = 1.01–1.03, P = 0.0002), independent of age, gender, body mass index (BMI), smoking, diabetes, hypercholesterolemia and creatinine (Cr). This association was still of statistical significance in subgroup analysis of hypertension and diabetes.

Conclusion

Increasing brachial PP was significantly and independently associated with increased risk of multivessel coronary disease in stable angina patients. The association of brachial PP with CAD was more pronounced in hypertension group than in non-hypertension one.

Arterial wave reflection is associated with severity of extracoronary atherosclerosis in patients with coronary artery disease

BACKGROUND

Arterial wave reflection is a major determinant of left ventricular function, coronary perfusion and cardiovascular risk. We investigated whether arterial wave reflection may detect atherosclerosis of peripheral arteries in patients with documented coronary artery disease (CAD).

METHODS

Radial artery applanation tonometry and pulse wave analysis was performed in 184 patients with documented CAD at coronary angiography; central blood pressures and augmentation index (AI) were measured. Ankle-brachial (ABI) index and intima-media thickness (IMT) were used as indices of atherosclerosis of the lower limbs and the carotid arteries respectively.

RESULTS

Patients with abnormal IMT (> 0.7 mm, first tertile) or ABI (< 0.94, first tertile) had higher AI than patients with lower IMT or higher ABI (24 +/- 17 versus 17 +/- 16% and 23 +/- 18 versus 18 +/- 13%, respectively, P < 0.05). In multivariate analysis, increasing AI was associated with age, female gender, heart rate, mean blood pressure, hyperlipidaemia, and use of statins (regression coefficient (beta) = 0.50, beta = 0.15, beta = -0.60, beta = 0.23, beta = 0.16 and beta = -0.14, respectively, P < 0.05). Increasing AI was associated with an adjusted-odds ratio of 1.035 [95% confidence interval (CI), 1.005-1.066], P = 0.02 for an abnormal IMT and of 1.08 (95% CI, 1.024-1.146), P = 0.005 for ABI after adjustment for age, gender, heart rate, height, blood pressure, atherosclerotic risk factors, obesity and medication. No relation was found between AI and Gensini score or for the number of diseased coronary vessels.

CONCLUSION

Augmentation index is a marker of extensive extracoronary atherosclerosis in patients with CAD.

Sex Difference in the Association Between Brachial Pulse Pressure and Coronary Artery Disease: The Korean Women's Chest Pain Registry (KoROSE)

This study was performed to investigate the association between brachial pulse pressure (PP) and the presence/extent of obstructive coronary artery disease (CAD) in men and women. Study data were obtained from a nation-wide registry composed of 632 patients (173 men and 459 women, 58.1±10.5 years) with suspected CAD who underwent invasive coronary angiography. PP was higher in patients with obstructive CAD (≥50% stenosis) than those without CAD in both sexes (P=.032 in men; P<.001 in women). However, PP increased proportionally with the increasing number of obstructed coronary arteries in women (P<.001) but not in men (P=.070). Multiple logistic-regression analyses demonstrated that higher PP (≥50.5 mm Hg) was an independent factor for determining obstructive CAD even after controlling for potential confounders in women (odds ratio, 2.83; 95% confidence interval, 1.40-5.73; P=.004). These results were consistent in 173 selected women matched with 173 men based on age and CAD severity. In conclusion, the association between brachial PP and obstructive CAD was more pronounced in women than in men. Brachial PP can be a simple and useful indicator of CAD especially in women.

Aortic flow propagation velocity, epicardial fat thickness, and osteoprotegerin level to predict subclinical atherosclerosis in patients with nonalcoholic fatty liver disease

Objective:

Nonalcoholic fatty liver disease is the most common cause of liver dysfunction in Western countries and an independent risk factor for atherosclerotic heart disease. Appropriate noninvasive parameters are lacking for optimal risk stratification of cardiovascular disease in these patients. We evaluated several recently discovered noninvasive parameters for atherosclerosis in patients with nonalcoholic fatty liver disease: epicardial fat thickness, aortic flow propagation velocity, and osteoprotegerin level.

Methods:

Forty-one patients (27 men and 14 women; mean age, 37.9±8.9 years) with nonalcoholic fatty liver disease and 37 control subjects (17 men and 20 women; mean age, 34.5±8.6 years) were enrolled in this observational case-control study. Patients with nonalcoholic fatty liver disease diagnosed at a gastroenterology outpatient clinic were included. Patients with cardiac pathology other than hypertension were excluded. Epicardial fat thickness and aortic flow propagation velocity were measured by echocardiography. The serum concentration of osteoprotegerin was measured using a commercial enzyme-linked immunosorbent assay kit.

Results:

Nonalcoholic fatty liver disease patients exhibited a significantly lower aortic flow propagation velocity (155.17±30.00 vs. 179.00±18.14 cm/s, p=0.000) and significantly higher epicardial fat thickness (0.51±0.25 vs. 0.29±0.09 cm, p=0.000) than control subjects. Osteoprotegerin levels were higher, but not significant, in patients with nonalcoholic fatty liver disease (28.0±13.0 vs. 25.2±10.8 pg/mL, p=0.244). Binary logistic regression analysis showed that aortic flow propagation velocity (OR, –0.973; 95% CI, 0.947–0.999) and waist circumference (OR, –1.191; 95% CI, 1.088–1.303) were independent predictors of nonalcoholic fatty liver disease.

Conclusion:

In this study, epicardial fat thickness and osteoprotegerin level were higher and aortic flow propagation velocity was lower in patients with nonalcoholic fatty liver disease. Early detection of abnormal epicardial fat thickness and aortic flow propagation velocity may warrant a search for undetected cardiovascular disease in patients with nonalcoholic fatty liver disease. (Anatol J Cardiol 2016; 16: 974-9)

Vascular effects and safety of supplementation with shark liver oil in middle-aged and elderly males

Shark liver oil (SLO) has long been used as a traditional health food, with a particular benefit for vascular health, in Japan. The aim of this study was to assess the effect of dietary supplementation with SLO on arterial stiffness and peripheral microvascular function in otherwise healthy middle-aged and older males with slightly increased arterial stiffness. A randomized, double-blind, placebo-controlled, parallel study design was used to assign 41 healthy males with a mean age of 59.0±4.0 years (range, 45-69 years) to either SLO (n=21) or placebo (n=20) treatment for eight weeks. The effects on arterial stiffness and peripheral microvascular function were assessed by the cardio-ankle vascular index (CAVI) and by measurement of hand blood flow to cutaneous tissues using a laser Doppler perfusion imaging (LDPI) technique, respectively. Although the magnitude of the changes in the CAVI value during the eight-week intervention for the SLO group did not significantly differ from that for the placebo group, the changes in the CAVI value for the former group were significantly associated (r=0.575, P<0.01) with age. It was also found that the LDPI values at week 8 were significantly lowered (P<0.05) compared with the baseline values in the placebo group, while no change was observed in the SLO group, resulting in a significant difference in the changes between the two groups (P=0.002). Neither SLO supplementation-related adverse side-effects nor any abnormal changes in routine laboratory tests, including lipid profiles and anthropometric and haemodynamic parameters, were observed throughout the intervention. SLO may have the potential to safely improve vascular health in middle-aged and elderly males.

Use and limitations of cardiac magnetic resonance derived measures of aortic stiffness in patients after acute myocardial infarction

INTRODUCTION

Cardiac magnetic resonance (CMR) is a unique method to determine regional and local aortic stiffness parameters. Although various methods have been validated, there are no data in patients after acute ST-segment elevation myocardial infarction (STEMI). In the present study we assessed the feasibility of different CMR derived measures of aortic stiffness in patients after first acute STEMI for the first time.

METHODS

CMR derived aortic pulse wave velocity (PWV) determined by the regional transit-time (PWVTT) and local flow-area (PWVQA) method as well as local distensibility coefficients (DCs) was analyzed in 22 healthy young volunteers and 28 patients with recent acute STEMI.

RESULTS

PWVTT and DC of the ascending aorta differed significantly between healthy subjects and STEMI patients (all p<0.001). PWVQA at thoracic levels of aorta was not different between groups (p>0.520) and did not correlate with age (p>0.149) and PWVTT (p>0.310). Intra- and interobserver variability was high for PWVTT (r=0.970, p<0.001 and r=0.920, p<0.001), acceptable for DC (all r>0. 809, p<0.001 and all r>0.510, p<0.001) but low for thoracic PWVQA (all r<0.330 and all r<0.372).

CONCLUSION

PWVTT and local DC are robust methods for the assessment of aortic stiffness in patients after acute STEMI.

Relation of plasma adiponectin levels and aortic stiffness after acute ST-segment elevation myocardial infarction

BACKGROUND

Pulse wave velocity is a measure of aortic stiffness and an independent predictor of cardiovascular morbidity and mortality. Adiponectin is involved in atherosclerosis and inflammation. In the present study we aimed to explore the association between plasma adiponectin concentrations and pulse wave velocity in the acute phase after ST-segment elevation myocardial infarction (STEMI).

METHODS

Forty-six consecutive STEMI patients (mean age 57 ± 11 years) treated with primary percutaneous coronary intervention (PCI) were enrolled in this cross-sectional study. Plasma adiponectin was measured 2 days after index event by enzyme-linked immunosorbent assay. Aortic pulse wave velocity (PWV) was calculated by the transit-time method with the use of a velocity-encoded, phase-contrast cardiac magnetic resonance protocol.

RESULTS

Median plasma adiponectin concentration was 2385 ng/ml (interquartile range 1735-5403). Males had lower plasma adiponectin values than females and current smokers had lower values than non-smokers (all p<0.02). Adiponectin was significantly associated with PWV (r=0.505, p<0.001), age (r=0.437, p=0.002), and total cholesterol (r=0.468, p=0.001). Multiple linear regression analysis revealed adiponectin as a predictor of PWV independently of age, sex, smoking status, total cholesterol, and N-terminal pro-B-type natriuretic peptide (p=0.027).

CONCLUSIONS

Plasma adiponectin concentrations are strongly associated with aortic stiffness in patients after acute STEMI treated with primary PCI. Our data support a possible role for adiponectin as an independent risk marker for increased aortic stiffness in STEMI patients.

Association of resting heart rate with carotid and aortic arterial stiffness: multi-ethnic study of atherosclerosis

Resting heart rate is an easily measured, noninvasive vital sign that is associated with cardiovascular disease events. The pathophysiology of this association is not known. We investigated the relationship between resting heart rate and stiffness of the carotid (a peripheral artery) and the aorta (a central artery) in an asymptomatic multi-ethnic population. Resting heart rate was recorded at baseline in the Multi-Ethnic Study of Atherosclerosis (MESA). Distensibility was used as a measure of arterial elasticity, with a lower distensibility indicating an increase in arterial stiffness. Carotid distensibility was measured in 6484 participants (98% of participants) using B-mode ultrasound, and aortic distensibility was measured in 3512 participants (53% of participants) using cardiac MRI. Heart rate was divided into quintiles and we used progressively adjusted models that included terms for physical activity and atrioventricular nodal blocking agents. Mean resting heart rate of participants (mean age, 62 years; 47% men) was 63 bpm (SD, 9.6 bpm). In unadjusted and fully adjusted models, carotid distensibility and aortic distensibility decreased monotonically with increasing resting heart rate (P for trend <0.001 and 0.009, respectively). The relationship was stronger for carotid versus aortic distensibility. Similar results were seen using the resting heart rate taken at the time of MRI scanning. Our results suggest that a higher resting heart rate is associated with an increased arterial stiffness independent of atrioventricular nodal blocker use and physical activity level, with a stronger association for a peripheral (carotid) compared with a central (aorta) artery.

Aortic Compliance and Stiffness Among Severe Longstanding Hypertensive and Non-hypertensive

Introduction

Abnormal aortic function in hypertension is generally attributed to accelerated breakdown of elastin in the aorta, leading to dilatation of the lumen and stiffening of the wall as elastin is replaced with stiffer collagen. Aortic stiffness is an independent predictor of cardiovascular risk and all-cause and cardiovascular mortality. Vascular stiffening can activate endothelium which in turn may promote atherogenesis. Modulation of arterial stiffness has been shown to be successfully managed via changes in lifestyle and put under control of hypertension pharmacologically with antihypertensive drugs and statins.

Methods

Hundred and forty four patients have been enrolled in this study. They have been divided in two groups, with hypertension and group of control. Groups were with no age difference.

Results

Group with hypertension were with reduced aortic strain, distensibility (compliance) and have higher stiffness than control group; GrHTA =9.3 compared to GC=5.4. After successful treatment of hypertension with antihypertensives and statins, for two years, these parameters showed improvement, but still remain out of normal range compared to control group; 7.6 vs. 5.38.

Conclusions

Hypertensive patients have reduced aortic elasticity and increased stiffness which can be stopped and improved after treatment with antihypertensive and statin.

A knowledge-based approach to arterial stiffness estimation using the digital volume pulse

We have developed a knowledge based approach for arterial stiffness estimation. The proposed new approach reliably estimates arterial stiffness based on the analysis of age and heart rate normalized reflected wave arrival time. The proposed new approach reduces cost, space, technical expertise, specialized equipment, complexity, and increases the usability compared to recently researched noninvasive arterial stiffness estimators. The proposed method consists of two main stages: pulse feature extraction and linear regression analysis. The new approach extracts the pulse features and establishes a linear prediction equation. On evaluating proposed methodology with pulse wave velocity (PWV) based arterial stiffness estimators, the proposed methodology offered the error rate of 8.36% for men and 9.52% for women, respectively. With such low error rates and increased benefits, the proposed approach could be usefully applied as low cost and effective solution for ubiquitous and home healthcare environments.

Impaired distensibility of ascending aorta in patients with HIV infection

Background

Our aim was to investigate the aortic distensibility (AD) of the ascending aorta and carotid artery intima-media thickness (c-IMT) in HIV-infected patients compared to healthy controls.

Methods

One hundred and five HIV-infected patients (86 males [82%], mean age 41 ± 0.92 years), and 124 age and sex matched HIV-1 uninfected controls (104 males [84%], mean age 39.2 ± 1.03 years) were evaluated by high-resolution ultrasonography to determine AD and c-IMT. For all patients and controls clinical and laboratory factors associated with atherosclerosis were recorded.

Results

HIV- infected patients had reduced AD compared to controls: 2.2 ± 0.01 vs. 2.62 ± 0.01 10^-6 cm² dyn^-1, respectively (p < 0.001). No difference was found in c-IMT between the two groups. In multiadjusted analysis, HIV infection was independently associated with decreased distensibility (beta –0.45, p < 0.001). Analysis among HIV-infected patients showed that patients exposed to HAART had decreased AD compared to HAART-naïve patients [mean (SD): 2.18(0.02) vs. 2.28(0.03) 10^-6 cm² dyn^-1, p = 0.01]. In multiadjusted analysis, increasing age and exposure to HAART were independently associated with decreased AD.

Conclusion

HIV infection is independently associated with decreased distensibility of the ascending aorta, a marker of subclinical atherosclerosis. Increasing age and duration of exposure to HAART are factors further contributing to decreased AD.

Arterial stiffness and wave reflection: sex differences and relationship with left ventricular diastolic function

Increased arterial stiffness and wave reflection have been reported in heart failure with normal ejection fraction (HFNEF) and in asymptomatic left ventricular (LV) diastolic dysfunction, a precursor of HFNEF. It is unclear whether women, who have higher frequency of HFNEF, are more vulnerable than men to the deleterious effects of arterial stiffness on LV diastolic function. We investigated, in a large community-based cohort, whether sex differences exist in the relationship among arterial stiffness, wave reflection, and LV diastolic function. Arterial stiffness and wave reflection were assessed in 983 participants from the Cardiovascular Abnormalities and Brain Lesions study using applanation tonometry. The central pulse pressure/stroke volume index, total arterial compliance, pulse pressure amplification, and augmentation index were used as parameters of arterial stiffness and wave reflection. LV diastolic function was evaluated by 2-dimensional echocardiography and tissue-Doppler imaging. Arterial stiffness and wave reflection were greater in women compared with men, independent of body size and heart rate (all P<0.01), and showed inverse relationships with parameters of diastolic function in both sexes. Further adjustment for cardiovascular risk factors attenuated these relationships; however, a higher central pulse pressure/stroke volume index predicted LV diastolic dysfunction in women (odds ratio, 1.54; 95% confidence intervals, 1.03 to 2.30) and men (odds ratio, 2.09; 95% confidence interval, 1.30 to 3.39), independent of other risk factors. In conclusion, in our community-based cohort study, higher arterial stiffness was associated with worse LV diastolic function in men and women. Women's higher arterial stiffness, independent of body size, may contribute to their greater susceptibility to develop HFNEF.

Vascular stiffness and aging in HIV

Large artery stiffening is a biological index of vascular aging. Vascular aging and atherosclerosis are two closely linked processes that develop in parallel and in synergy, sharing common aetiological determinants. Vascular stiffening increases left ventricular work and can lead to diminished coronary perfusion, and may therefore contribute to the development of cardiovascular disease. There is emerging evidence that large artery stiffness and vascular aging are accelerated in HIV infection because of the high prevalence of cardiovascular risk factors among HIV-infected patients. Moreover, the biological effects of HIV and the metabolic perturbations associated with antiretroviral therapies appear to accelerate vascular stiffening in HIV-infected patients. Further studies evaluating the effects of general and targeted therapies and various combinations of antiretroviral therapies on measures of large artery stiffness are urgently needed.

Arterial wave reflection and subclinical left ventricular systolic dysfunction

OBJECTIVES

Increased arterial wave reflection is a predictor of cardiovascular events and has been hypothesized to be a cofactor in the pathophysiology of heart failure. Whether increased wave reflection is inversely associated with left-ventricular (LV) systolic function in individuals without heart failure is not clear.

METHODS

Arterial wave reflection and LV systolic function were assessed in 301 participants from the Cardiovascular Abnormalities and Brain Lesions (CABL) study using two-dimensional echocardiography and applanation tonometry of the radial artery to derive central arterial waveform by a validated transfer function. Aortic augmentation index (AIx) and wasted energy index (WEi) were used as indices of wave reflection. LV systolic function was measured by LV ejection fraction (LVEF) and tissue Doppler imaging (TDI). Mitral annulus peak systolic velocity (Sm), peak longitudinal strain and strain rate were measured. Participants with history of coronary artery disease, atrial fibrillation, LVEF less than 50% or wall motion abnormalities were excluded.

RESULTS

Mean age of the study population was 68.3 ± 10.2 years (64.1% women, 65% hypertensive). LV systolic function by TDI was lower with increasing wave reflection, whereas LVEF was not. In multivariate analysis, TDI parameters of LV longitudinal systolic function were significantly and inversely correlated to AIx and WEi (P values from 0.05 to 0.002).

CONCLUSIONS

In a community cohort without heart failure and with normal LVEF, an increased arterial wave reflection was associated with subclinical reduction in LV systolic function assessed by novel TDI techniques. Further studies are needed to investigate the prognostic implications of this relationship.

AORTIC PULSE WAVE VELOCITY MEASURED BY PULSE WAVE IMAGING (PWI): A COMPARISON WITH APPLANATION TONOMETRY

BACKGROUND

Arterial stiffness is a well-established indicator of cardiovascular disease outcome. Pulse Wave Velocity (PWV) is a surrogate for arterial stiffness that is measured either globally using carotid to femoral applanation tonometry or locally using biomedical imaging methods. Pulse Wave Imaging (PWI) is an ultrasound-based method for both qualitative visualisation of pulse wave propagation and quantitative estimation of arterial stiffness. The objective of this study is to assess the PWI performance in PWV estimation by comparing local abdominal aortic PWV values obtained by PWI to the carotid-femoral PWV measured by applanation tonometry.

METHODS

A total of 18 subjects (age 18-66, 32.5±14.5) with no history of cardiovascular disease were consecutively tested by both PWI and tonometry.

RESULTS

The correlation coefficient r between values found by the two methods was found to be equal to 0.68. A linear regression yielded PWV_PWI = 1.02* PWV_tonometry +0.15. Tukey mean-difference plots indicated that PWV_PWI was significantly lower than PWV_tonometry (-0.3 m/s) at lower PWV values (PWV≤7 m/s), whereas PWV_PWI was significantly higher (+1.4 m/s) than PWV_tonometry at higher PWV values (PWV>7 m/s).

CONCLUSIONS

Despite the regional nature of the PWV_PWI measurements, as opposed to the global PWV_tonometry measurements, abdominal PWV_PWI and carotid-femoral PWV_tonometry values were found to be similar, with an average bias equal to 0.25 m/s. Such a bias and its variation with PWV may be partially explained by both physiological variations of PWV along the arterial tree and by the increasing uncertainty of the PWV estimate by PWI as PWV increases.

Arterial aging--hemodynamic changes and therapeutic options

Arterial aging can be attributed to two different pathophysiological changes--increase in arterial stiffness and disturbed wave reflections. The capacity of the aorta to absorb the force exerted by the left ventricular ejection and dampen pulsatile flow becomes diminished with advancing age, owing to the progressive hardening of the arterial wall. These changes contribute to increase blood pressure, mainly systolic blood pressure and pulse pressure, which can trigger cardiovascular events. Understanding the pulsatile arterial hemodynamics that elevate cardiovascular risk has led to the use of pharmacological therapies, which prevent arterial stiffness and reduce wave reflections, and improve cardiovascular morbidity and mortality. Antifibrotic agents, such as those that block the renin-angiotensin-aldosterone pathway, are often given in association with diuretics, calcium-channel blockers, or both, but not with standard beta-blockers. Consistent reductions in cardiovascular outcomes obtained using these agents can be predicted through noninvasive measurements of central systolic blood pressure and pulse pressure.

Aortic wave reflection in women and men

Augmentation index (AIx), a marker of the number of aortic wave reflections (AWRs), is influenced not only by the magnitude of incident and reflected pressure waves but also by the time of return. A new triangulation method has been developed, enabling us to better quantify AWRs and to determine their sex differences, which may relate to body size or pulse pressure (PP) amplification, measured from the brachial PP-to-carotid PP (B/C) ratio. With the use of pulse wave analysis, AWRs were evaluated in 51 women and 72 men treated for hypertension and studied in relationship to age, blood pressure, and pulse wave velocity. When women were compared with men, AIx (expressed in %PP and adjusted to heart rate) was significantly higher, together with a significant decrease of the B/C ratio and an increase of the reflection magnitude and of the amplitude (but not the timing) of the backward pressure wave. The significance of the amplitude difference between men and women was enhanced after an adjustment to heart rate or pulse wave velocity but was abolished after an adjustment to body height or the B/C ratio. In the overall population, AIx and the reflection magnitude index were positively (r(2) = 0.39) and independently associated, after excluding confounding factors such as drug treatment. In conclusion, when compared with men, women treated for hypertension have increased AIx, related to the increased amplitude, and not timing, of backward pressure waves. This finding relates to sex differences in body size and mostly brachial-carotid PP amplification, a parameter highly related to the sex difference of cardiovascular risk.

Pulse wave imaging for noninvasive and quantitative measurement of arterial stiffness in vivo

BACKGROUND

Arterial stiffening is recognized to be associated with increased cardiovascular mortality and to be a major cause of several cardiovascular complications. Pulse wave velocity (PWV) has been widely accepted to be a reliable and robust measure of arterial stiffness. In this article, the novel ultrasound-based pulse wave imaging (PWI) method is hereby proposed for visualization of the pulse wave during its propagation and for calculation of the PWV.

METHODS

The PWV is estimated by measuring the spatiotemporal variation of the pulse wave-induced displacement of the arterial wall within the imaged segment. The method is compared to mechanical testing on aortic phantoms in order to evaluate its reliability and accuracy, and in vivo results are presented on normal abdominal aortas (N = 11).

RESULTS

Good agreement was found with mechanical testing on phantoms (r(2) = 0.92), showing the reliability of the method. In vivo average PWV and Young's modulus were found to be equal to 4.4 +/- 0.6 m/s and 108 +/- 27 kPa, respectively.

CONCLUSIONS

Reliability and in vivo feasibility of the proposed PWI method were demonstrated in this study. Its simplicity of use and its capability of providing regional PWV render PWI a valuable tool for quantitative assessment of arterial stiffness. The utility of the method in a clinical setting has yet to be established and is part of an ongoing clinical study.

Cardio-ankle vascular index is independently associated with the severity of coronary atherosclerosis and left ventricular function in patients with ischemic heart disease

AIM

The cardio-ankle vascular index (CAVI) has been proposed as a new noninvasive marker of arterial stiffness independent of blood pressure. We investigated the association of the CAVI with coronary atherosclerosis and left ventricular (LV) systolic and diastolic function in patients with ischemic heart disease (IHD).

METHODS

A total of 206 consecutive subjects undergoing coronary angiography were enrolled. CAVI measurement and echocardiography were performed simultaneously. Patients having significant coronary stenosis were classified into the IHD group.

RESULTS

CAVI in the IHD group (n=133) was significantly higher than in the non-IHD group(n=73)(9.1+/-1.3 vs. 8.7+/-1.2, p=0.02). In all IHD patients, CAVI was negatively correlated with LV ejection fraction (LVEF)(r=-0.31, p<0.01), LV mass index (r=0.24, p<0.01) and angiographic scores of coronary atherosclerosis. Stepwise regression analysis revealed that CAVI was independently associated with LVEF, along with a history of myocardial infarction, LV mass index, and left atrial diameter in all IHD patients (p<0.01). In the sub-analysis of IHD patients with preserved LVEF, CAVI was correlated with echocardiographic parameters regarding LV diastolic function. Multivariate analysis demonstrated that the increased CAVI was significantly associated with LV diastolic dysfunction in patients with preserved LVEF.

CONCLUSION

CAVI, a new parameter of aortic stiffness, was independently associated with LV systolic and diastolic function as well as coronary artery disease in IHD patients.

De-stiffening drug therapy and blood pressure control

In hypertensive subjects, cardiovascular risk reduction is critically related to the decrease of systolic blood pressure (SBP). De-stiffening therapy means that, in a controlled therapeutic trial of long duration, a selective reduction of SBP has been obtained in the studied group by comparison with the control group, and that this SBP reduction is due to a decrease of either arterial stiffness, or wave reflections, or both. Central SBP reduction and cardiovascular remodeling are specifically involved. Most protocols require the presence of an angiotensin II blocker, potentially associated with a diuretic compound and/or a calcium-channel blocker. Cardiovascular outcomes are significantly reduced by comparison with the control group, particularly when this latter group involves administration of a beta-blocking agent.

Relation of left ventricular mass and concentric remodeling to extent of coronary artery disease by computed tomography in patients without left ventricular hypertrophy: ROMICAT study

OBJECTIVE

Cardiac computed tomography allows for simultaneous assessment of left ventricular mass (LVM) and coronary artery disease (CAD). We aimed to determine whether LVM, LVM index (LVMi), and the left ventricular geometric pattern of concentric remodeling are associated with the extent of CAD in patients without left ventricular hypertrophy.

METHODS

In 348 patients from the Rule Out Myocardial Infarction Using Computer Assisted Tomography trial, 64-slice computed tomography was performed and LVM measured at end-diastole. We used three LVM indexation criteria to obtain three cohorts: LVM indexed to body surface area by echocardiography (n = 337) and computed tomography criteria (n = 325), and by height (n = 326). The cohorts were subdivided into concentric remodeling and normal geometry. Extent of coronary plaque was classified based on a 17-segment model, treated as a continuous variable, and stratified into three groups: zero segment, one to four segments, and more than four segments.

RESULTS

Patients with more than four segments of coronary plaque had higher LVM (Delta12.8-15.1 g) and LVMi (Delta4.0-5.5 g/m and Delta2.2 g/m) than those without CAD (all P < or = 0.03). After multivariable adjustment, LVM and LVMi remained independent predictors of extent of coronary plaque, with 0.27-0.29 segments more plaque per 20 g increase of LVM (all P = 0.02), 0.32-0.34 segments more plaque per 10 g/m increase of LVMi (both P = 0.02), and 0.80 segments more plaque per 10 g/m increase of LVMi (P = 0.008). Concentric remodeling patients had 1.1-1.3 segments more plaque than those with normal geometry (all P < or = 0.05). Patients with more than four segments of plaque had two-fold increase in odds (all P < or = 0.05) of having concentric remodeling as compared with those without CAD.

CONCLUSION

Increased LVM, LVMi, and concentric remodeling are associated with a greater degree of coronary plaque burden in patients without left ventricular hypertrophy. These findings could provide an indication to intensify medical therapy in patients with subclinical CAD and hypertension.

Aortic stiffness and distensibility among hypertensives

Hypertension is one among many factors that contribute to aortic stiffness, which has repercussions mainly on the heart. To assess aortic stiffness among essential hypertensives of South India and its relationship with gender. An analytical study was designed to assess aortic stiffness among 60 nonobese, nonalcoholic, nonsmoking, and non-caffeine consuming essential hypertensives without any overt illness or infection, and compared with 30 healthy age- and sex-matched nonhypertensives. They were assessed clinically and also by laboratory means. Their left ventricular mass (LV) and left ventricular ejection fraction (LVEF) were measured using Transthoracic echocardiogram. Aortic systolic and diastolic diameters were measured by using M-mode echocardiography during consecutive beats and averaged for each case. Finally, aortic stiffness was calculated. The data were analyzed statistically. Hypertensives were divided into Group I, consisting of patients with hypertension at least for 5 years, who were not adherent to medication, and Group II, consisting of patients with hypertension of duration between 6 months and 1 year. There were 20 males and 10 females in each group. There was no significant difference between the hypertensive groups and a control, normotensive, group with regard to BMI or total cholesterol. The means of LV mass (in grams), systolic BP (in mmHg), diastolic BP (in mmHg), aortic systolic diameter (in mm), aortic diastolic diameter (in mm), aortic distensibility (in mm), and aortic stiffness found in Group I, Group II, and controls were 105.8 +/- 23.8, 101.5 +/- 21, and 84 +/- 9.8; 138 +/- 14.2, 153 +/- 17.1, and 120 +/- 8.3; 90.5 +/- 11.6, 101.7 +/- 17.1, and 76.5 +/- 5; 30.85 +/- 2.6, 28.7 +/- 2.6, and 27.7 +/- 2.4; 28.7 +/- 2.2, 25.8 +/- 2.5, and 24.2 +/- 2.5; 2.14 +/- 0.3, 2.84 +/- 0.5, and 3.5 +/- 0.6; and 1.31 +/- 0.09, 1.14 +/- 0.1, and 1.04 +/- 0.08, respectively. The differences between the hypertensive groups and the control group were significant. Aortic stiffness was greater in hypertensives and it was independent of gender, but increased with duration of hypertension. Hypertension has effects on the aorta (decreased aortic distensibility and increased aortic stiffness) and left ventricle (increased left ventricular mass and left ventricular hypertrophy). These changes can be identified and monitored while the patient is on antihypertensive therapy along with life-style modifications, as these are reversible. Nevertheless, these aspects do not receive due attention in medical education and training on hypertension.

Hypertension, systolic blood pressure, and large arteries

This article discusses the following: (1) factors modulating central and peripheral SBP and PP in hypertensive subjects; (2) mechanisms enhancing PP variations in this population; (3) Analysis of pulsatile arterial hemodynamics as predictors of CV risk; and (4) Pulsatile hemodynamics and strategies lowering CV risk in the treatment of hypertension.

Renal function is associated with arterial stiffness and predicts outcome in patients with coronary artery disease

BACKGROUND

Arterial stiffness (AS) is associated, and a predictor of, outcome in patients with cardiovascular and renal disease.

AIM

In this study, we estimated glomerular filtration rate (eGFR) and measured indices of AS in patients with suspected coronary artery disease (CAD), and assessed their predictive value on outcome.

DESIGN

Prospective cohort study.

METHODS

AS was measured using pulse wave velocity (PWV) and pulse wave analysis in patients with no known renal disease who had recently undergone coronary angiography. Renal function was assessed using serum creatinine concentration [creat](sr) and eGFR (Cockcroft & Gault, C&G). The primary endpoint was a combination of hospitalization due to cardiovascular disease and all-cause mortality.

RESULTS

Two hundred eighty-four subjects (210 men, 74 women, mean age 62 years) were followed-up for a mean of 1.5 years. PWV was negatively associated with eGFR (r(2) = 0.09, P < 0.001), even in patients with an eGFR > or =60 ml/min/m(2) (r(2) = 0.04, P < 0.01). PWV was determined by age, heart rate, systolic blood pressure, body mass index and [creat](sr) (r(2) = 0.38, P < 0.001). A lower eGFR (P < 0.01), PWV above the median (P < 0.05) and degree of CAD (P < 0.001) predicted a shorter time to the primary endpoint. eGFR and degree of CAD remained independent determinants of outcomes (P < 0.01), even in patients with normal renal function (P < 0.01).

CONCLUSION

This study suggests that even minor reductions in eGFR, within the normal range, are an additional independent risk marker in patients with CAD.

Pulse pressure and coronary atherosclerosis in asymptomatic type 2 diabetes mellitus: a 64 channel cardiac computed tomography analysis

BACKGROUND

Identification of high risk sub-groups for early initiation of preventive medical therapy requires widespread population screening using simple, inexpensive tests. High pulse pressure has been shown to predict adverse coronary events. We examined if this correlation was related to a greater coronary plaque burden in patients with high pulse pressure using 64 channel coronary computed tomographic angiography (CCTA) in patients with type 2 diabetes mellitus.

METHODS

The study included 427 consecutive asymptomatic diabetic patients with no history of coronary disease, (age 55-74 years, 58% women), undergoing CCTA as part of a prospective outcomes study.

RESULTS

Coronary atheroma was present in 76.6% of patients, multivessel coronary atheroma in 55.1% and luminal stenosis (>or=50% of diameter) in 22.9%. Pulse pressure (adjusted for age, gender, mean blood pressure and heart rate) correlated with number of coronary arteries with atheroma (p=0.005) and with multivessel coronary atheroma (odds ratio 1.24 95%CI 1.06-1.43 for each 10 mm Hg pulse pressure, p=0.009). The correlation was independent of Framingham and United Kingdom Prospective Diabetic Study risk scores (p=0.027 and p=0.036 respectively). Adjusted pulse pressure also correlated with quartiles of coronary artery calcium score (p=0.009).

CONCLUSION

Elevated pulse pressure was a useful independent marker of presence and extent of pre-clinical coronary artery disease in an asymptomatic diabetic population.

Cardiovascular Risks Associated With Obesity in Children and Adolescents

Introduction: The aim of this paper is to review the cardiovascular (CVS) risks associated with obesity in children and adolescents. Both short-term and long-term CVS consequences, the mechanisms of how these develop and the measures that can alter or reverse these CVS events are reviewed. Materials and Methods:Selected publications include original articles and review papers that report on studies of CVS risks and consequences related to childhood obesity. Some papers that contain data from adults studies are also included if the contents help to explain some underlying mechanisms or illustrate the continuation of related CVS changes into adulthood. Results: Obese children and adolescents have an increased risk for CVS complications that include elevation of blood pressure, clustering of CVS risk factors (Metabolic Syndrome), changes to arterial wall thickness, elasticity and endothelium, as well as changes in left ventricular structure and function. Some of these cardiovascular problems may be initiated or potentiated by obstructive sleep apnoea that can accompany obesity in children. Many of such changes have been noted to reverse or improve with weight reduction. Conclusions:Early development of CVS risks in obese children and the possible continuation of CVS complications into adulthood have been observed. Obstructive sleep apnoea in obese children can further contribute to such CVS risks. These findings underscore the importance of prevention of childhood obesity as a priority over management of obesity in children. The prevalence of obesity has risen by three-folds or more in many countries since 1980. In 2005, it was estimated that globally there are about 1.6 billion overweight adults and at least 400 million of them are obese. This increase in the prevalence of adults being overweight and obese comes with a heavy price. The cost of healthcare has significantly increased and is expected to increase even more because of the close association between obesity and various chronic diseases. Key words: Endothelial function, Hypertension, Metabolic syndrome, Obstructive sleep apnoea

Stress responses and baroreflex function in coronary disease

Exaggerated pressor responses to mental stress in patients with coronary artery disease (CAD) are associated with increased risk for subsequent cardiovascular events. The integrated baroreflex gain and its mechanical and neural component were estimated and then related to the blood pressure and heart rate responses to simulated real-life stressors: mental arithmetic and public speaking. Eighteen healthy individuals (aged 61 +/- 8 yr) and 29 individuals with documented CAD but no other comorbidities (aged 59 +/- 8 yr) were studied. Heart rate and blood pressures were continuously assessed before, during preparation for, and during performance of a math task and a speech task. The assessment of beat-to-beat carotid diameters during baroreflex engagement was used to estimate the integrated baroreflex gain and its mechanical and neural component. The CAD subjects demonstrated significantly greater increases in heart rate and blood pressures for the performance of the speech task. However, there were no group differences in integrated cardiovagal baroreflex gain or either mechanical or neural baroreflex component. These findings indicate that the augmented pressor responses in CAD do not result from a generalized arterial baroreflex deficit.

Aortic stiffness and the balance between cardiac oxygen supply and demand: the Rotterdam Study

OBJECTIVES

Aortic stiffness is an independent predictor of cardiovascular morbidity and mortality. We investigated whether aortic stiffness, estimated as aortic pulse wave velocity, is associated with decreased perfusion pressure estimated as the cardiac oxygen supply potential.

METHODS

Aortic stiffness and aortic pressure waves, reconstructed from finger blood pressure waves, were obtained in 2490 older adults within the framework of the Rotterdam Study, a large population-based study. Cardiac oxygen supply and demand were estimated using pulse wave analysis techniques, and related to aortic stiffness by linear regression analyses after adjustment for age, sex, mean arterial pressure and heart rate.

RESULTS

Cardiac oxygen demand, estimated as the Systolic Pressure Time Index and the Rate Pressure Product, increased with increasing aortic stiffness [0.27 mmHg s (95% confidence interval: 0.21; 0.34)] and [42.2 mmHg/min (95% confidence interval: 34.1; 50.3)], respectively. Cardiac oxygen supply potential estimated as the Diastolic Pressure Time Index decreased [-0.70 mmHg s (95% confidence interval: -0.86; -0.54)] with aortic stiffening. Accordingly, the supply/demand ratio Diastolic Pressure Time Index/Systolic Pressure Time Index -1.11 (95% confidence interval: -0.14; -0.009) decreased with increasing aortic stiffness.

CONCLUSION

Aortic stiffness is associated with estimates of increased cardiac oxygen demand and a decreased cardiac oxygen supply potential. These results may offer additional explanation for the relation between aortic stiffness and cardiovascular morbidity and mortality.

Vascular stiffness is related to superoxide generation in the vessel wall

OBJECTIVES

Oxidative stress causes endothelial dysfunction and plays a major role in the pathogenesis of cardiovascular disease. Increased vascular stiffness is an intermediate phenotype in the development of cardiovascular disease. We hypothesized that vascular stiffness is partially determined by oxidative stress.

METHODS

We examined 163 participants out of whom 80 had coronary artery disease. Vascular stiffness was assessed by pulse wave analysis, pulse wave velocity and measurement of aortic compliance by cardiac MRI. Circulating markers of oxidative stress and vascular superoxide generation in saphenous vein were measured.

RESULTS

After adjustment for age, sex, BMI, heart rate, blood pressure and lipids only carotid-femoral pulse wave velocity and aortic compliance were different between patients and control group. Aortic compliance was reduced (11.4 +/- 6.3 vs. 13.9 +/- 7.3 ml x 10(-3) per mmHg; P = 0.035) and vascular superoxide generation increased (1.01 +/- 0.45 vs. 0.76 +/- 0.44 nmol/mg per min; P = 0.035) in patients with coronary artery disease compared with those without. In a multiple stepwise regression analysis, aortic compliance was determined by age (P < 0.001) and vascular superoxide production (P = 0.033). CYBA C242T and NOS3 G894T polymorphisms had additive effects on vascular superoxide generation (P = 0.026) and xanthine oxidase activity was increased in patients with CAD (P = 0.043). Genetic factors (P = 0.033) and xanthine oxidase activity (P < 0.001) were also related to aortic compliance.

CONCLUSION

By measuring vascular superoxide generation and aortic compliance using cardiac MRI, we demonstrated a functional relationship between oxidative stress and vascular stiffness. Patients identified with high levels of vascular stiffness are most likely to benefit from strategies to reduce vascular oxidative stress.