Role of increased aortic stiffness in the pathogenesis of heart failure

The effect of cardiac resynchronization therapy on arterial stiffness and central hemodynamic parameters

INTRODUCTION

Cardiac resynchronization therapy (CRT) is a device-based method of treatment which decreases morbidity and mortality in heart failure with reduced ejection fraction (HFrEF). This study was aimed to investigate the effects of CRT on hemodynamic and arterial stiffness parameters evaluated by noninvasive method, and determine whether there is a correlation between the changes after CRT in these parameters and the clinical response to CRT or not.

METHODS

The study included 46 patients with HFrEF who were planned to undergo CRT implantation. Before the CRT implantation, clinical and demographic data were recorded from all patients. Hemodynamic and arterial stiffness parameters were measured oscillometrically by an arteriograph before CRT implantation. The patients were re-evaluated minimum three months after CRT; the above-mentioned parameters were measured again and compared to the pre-CRT period.

RESULTS

Compared to the period before CRT, mean systolic blood pressure (SBP) (116.8 ± 19.1 mm Hg vs 127.7 ± 20.9 mm Hg, P = .005), central SBP (cSBP) (106.2 ± 17.3 mm Hg vs 116.8 ± 18.7 mm Hg, P = .015), cardiac output (CO) (4.6 ± 0.8 lt/min vs 5.1 ± 0.8 lt/min, P = .002), stroke volume (65.6 ± 16.3 mL vs 72.0 ± 14.9 mL), and pulse wave velocity (PWV) (10 ± 1.6 m/sec vs 10.4 ± 1.8 m/sec, P = .004) increased significantly in post-CRT period. In addition, the same parameters were significantly increased post-CRT period in patients with clinical response. However, there was not any similar increase in nonresponder patients.

CONCLUSION

This study demonstrated that SBP, CO, and PWV increased significantly after CRT. The modest increases in these parameters were observed to be associated with positive clinical outcomes.

Does aortic pulse wave velocity have any prognostic significance in advanced heart failure patients?

Introduction: Noninvasive measurement of arterial stiffness by pulse-wave velocity (PWV) has prognostic value in different sub groups of cardiovascular disorders. We aimed to measure the PWV in advanced heart failure (HF) patients with reduced left ventricular ejection fraction (LVEF) and investigate whether it has any prognostic significance in this group of patients. Methods: Between 2013 to 2015 patients with a diagnosis of advanced HF (LVEF ≤ 30%) scheduled for right heart catheterization (RHC) were included in our study. PWV was measured before RHC in each patient using vascular explorer device (Enverdis GmbH) in catheterization laboratory. The patients were subsequently followed for 6 months and their hospitalization or death (composite of all-cause death/hospitalization) were recorded. Results: A total of 50 patients (38 men) were enrolled. The mean (SD) of age was 45 (16) years. The mean PWV was 6.8 m/s. There was no statistically significant correlation between the PWV and the clinical, echocardiographic and RHC data. The PWV was not different in patients with or without composite of all-cause death/hospitalization (7.3 versus 6.3, P > 0.05). In this study cardiac output (CO) (beta = -0.53, P = 0.02, odds ratio = 0.6, 95% CI = 0.4-0.9), pulse pressure (PP) (beta = -0056, P = 0.03, odds ratio=0.95, 95% CI = 0.89-0.99) and age (beta = -0.045, P = 0.05, odds ratio = 0.96, 95% CI = 0.9-1.001) were independent predictors of composite of all-cause death/ hospitalization. Conclusion: In patients with advanced systolic HF, PWV may not be a good prognostic factor and does not have any added value over previous well known prognostic factors.

Echocardiographic elastic properties of ascending aorta and their relationship with exercise capacity in patients with non-ischemic dilated cardiomyopathy

Background

: Aortic stiffness, an independent predictor of mortality and cardiovascular events, is common among patients affected by non-ischemic dilated cardiomyopathy (NIDC) and heart failure (HF).

Methods

: A total of 55 patients with diagnosis of NIDC (aged 60 ± 11 years, mean ejection fraction (EF) 35.2% ± 7.7%) admitted consecutively to our department for mild to moderate HF (NYHA class II–III) underwent an echocardiographic study and cardiopulmonary exercise test (CPX). We evaluated elastic properties of ascending aorta, i.e. aortic stiffness and aortic distensibility (mm Hg^{− 1}), derived from ascending aorta systolic and diastolic diameter (mm/m²) measured 3 cm above the valvular plane through 2D-guided M-mode echocardiography.

Results

: Mean aortic stiffness was 15.63 ± 14.53 and aortic distensibility was 2.61 ± 2.39 mm Hg^{− 1}. Collected parameters at CPX were peak oxygen consumption (pVO₂) (ml/kg/min), anaerobic threshold (AT) and the slope of the relation between minute ventilation (VE) and carbon dioxide production (VCO₂). Mean pVO₂ was 15.4 ± 3.9 ml/kg/min, VE/VCO₂ ratio at AT was 36.1 ± 6.1. Functional capacity measured through peak VO₂ was found to be directly correlated with aortic distensibility (r = 0.47, p = − 0.0002) and negatively correlated to aortic stiffness index (r = − 0.51, p = − 0.0001). These results were the same at multivariate analysis, corrected by age, hypertension, diabetes mellitus and ejection fraction (respectively r = 0.27, p = 0.008 and r = − 1.75, p = 0.0002).

Conclusions

: HF patients due to NIDC elastic properties of ascending aorta, evaluated by echocardiography, are correlated with a reduced functional capacity.

Effects of combined traditional Chinese exercises on blood pressure and arterial function of adult female hypertensive patients

This study examined the effects of combined traditional Chinese physical and mental exercises on the blood pressure of adult female hypertensive patients. Twenty female hypertensive patients aged between 50 and 60 years voluntarily participated in the study. The participants performed the combined exercises for 24 weeks, twice a week, and 60 min each time in low-to-moderate intensity. After the 24-week training, the participants showed significant decreases in systolic blood pressure (p = 0.000), diastolic blood pressure (p = 0.006), pulse pressure (p = 0.001), and right ankle brachial pressure index (p = 0.041). The combined Chinese traditional physical and mental exercises were found to have beneficial effects on adult female hypertensive patients.

β-blockade: benefits beyond blood pressure reduction?

Hypertension is a major cardiovascular (CV) risk factor, but several other common conditions, including chronic obstructive pulmonary disease (COPD), osteoporosis, and peripheral arterial disease (PAD), have been shown to independently increase the risk of CV events and death. The physiological basis for an increased CV risk in those conditions probably lies in the augmentations of oxidative stress, endothelial dysfunction, systemic inflammation, and arterial stiffness, which all are also hallmarks of hypertension. β-Blockers have been used for the treatment of hypertension for more than 40 years, but a number of meta-analyses have demonstrated that treatment with these agents may be associated with an increased risk of CV events and mortality. However, the majority of primary prevention β-blocker trials employed atenolol, an earlier-generation β(1) -selective blocker whose mechanism of action is based on a reduction of cardiac output. Available evidence suggests that vasodilatory β-blockers may be free of the deleterious effects of atenolol. The purpose of this review is to summarize pathophysiologic mechanisms thought to be responsible for the increased CV risk associated with COPD, osteoporosis, and PAD, and examine the possible benefits of vasodilatory β-blockade in those conditions. Our examination focused on nebivolol, a β(1) -selective agent with vasodilatory effects most likely mediated via β(3) activation.

Association of genetic variation on chromosome 9p21.3 and arterial stiffness

OBJECTIVES

Genome wide association studies have consistently reported associations between a region on chromosome 9p21.3 and a broad range of vascular diseases, such as coronary artery disease (CAD), aortic and intracranial aneurysms and type-2 diabetes (T2D). However, clear associations with intermediate phenotypes have not been described so far. To shed light on a possible influence of this chromosomal region on arterial wall integrity, we analysed associations between single nucleotide polymorphisms (SNPs) and degree of stiffness of the abdominal aorta in elderly individuals.

METHODS AND RESULTS

A total of 400 subjects, 212 men and 188 women, aged 70-88 years were included. Arterial stiffness was examined at the midpoint between the renal arteries and the aortic bifurcation. Two CAD- and aneurysm-associated SNPs (rs10757274 and rs2891168) and one T2D-associated SNP (rs1081161) within the 9p21.3 region were genotyped. Aortic compliance and distensibility coefficients were higher in carriers of the rs10757274G and rs2891168G alleles in men reflecting a decrease in aortic stiffness. Adjustment for age and mean arterial pressure had no effect on these associations. The two SNPs were not associated with intima-media thickness or lumen diameter of the abdominal aorta. There were no associations between the rs10811661 SNP and any measure of aortic stiffness.

CONCLUSIONS

Impaired mechanical properties of the arterial wall may explain the association between chromosome 9p21.3 polymorphisms and vascular disease.