Why are women more likely than men to develop heart failure with preserved ejection fraction?

Arterial stiffness, carotid atherosclerosis and left ventricular diastolic dysfunction in postmenopausal women

BACKGROUND

Postmenopausal women have an increased cardiovascular morbidity that may be due to the increase in classical cardiovascular risk factors and also to the arterial structure and function alterations. The aim of our study was to evaluate the association of aortic pulse wave velocity (PWV), and carotid intima-media thickness (IMT), with left ventricular diastolic dysfunction (LVDD) in postmenopausal women.

PATIENTS AND METHODS

In 96 women without overt cardiovascular disease (age 62±7.7 years), and with normal left ventricular systolic function, aortic PWV was assessed by using an oscillometric device, intima-media thickness was measured by B-mode ultrasonography and the parameters of left ventricular diastolic function were evaluated by a transthoracic echocardiographic study.

RESULTS

LVDD, defined as an E/A ratio≤1 was found in 50 patients (52%). All of them had mild LVDD. In these patients we found significant increase in age (p<0.001), aortic PWV (p<0.001), carotid IMT (p=0.002) and plaque score (p=0.004) when compared with patients without LVDD. In a logistic regression analyzed, after adjusting for age, only aortic PWV was a significant predictor of LVDD (2.15, 95% CI 1.39-3.31, p=0.0006).

CONCLUSIONS

This study among postmenopausal women provides evidence that increased arterial stiffness as measured by aortic PWV and not carotid IMT may be a marker or a risk factor for LVDD, independent of other classical risk factors.

Testosterone regulates cardiac contractile activation by modulating SERCA but not NCX activity

Alterations in intracellular Ca2+ transients of cardiomyocytes in orchidectomized (ORX) rats could be a cause of cardiac dysfunction in the hypogonadal condition. To investigate the role of male sex hormones in intracellular Ca2+ homeostasis during relaxation, Ca2+-handling activities by sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) and the Na+/Ca2+ exchanger (NCX) were evaluated in the ventricular muscle of 10-wk-old ORX rats with and without testosterone supplementation (2.5 mg/kg testosterone propionate, 2 times/wk). ORX induced a 50% decrease in contraction force accompanied by a prolonged time to achieve 50% relaxation ( T50) in isolated intact ventricular trabeculae, which was partially corrected by testosterone administration. Maximum active tension was also suppressed in ORX rats without changes in myofilament Ca2+ sensitivity and passive stiffness of the heart. Using a sarcoplasmic reticulum-enriched membrane preparation, the maximum thapsigargin-sensitive SERCA activity of the ORX rat was 27% lower with an increased Ca2+ sensitivity, which was prevented by testosterone treatment. However, neither changes in SERCA content nor its modulating components, sarcolipin and heat shock protein 20, were detected in the ORX rat, but there was a significant decrease in the phosphorylated Thr17 form of phospholamban. Despite a lower level of NCX protein in the heart of ORX rats, prolonged T50 disappeared after an incubation with thapsigargin (10 μM), implying a lack of effect of male sex hormone deficiency on NCX function. These findings indicate that male sex hormones can regulate cardiac relaxation by acting mainly through SERCA. However, a detailed mechanism of SERCA modulation under male sex hormone deficiency status remains to be explored.

Hemodynamic responses to rapid saline loading: the impact of age, sex, and heart failure

BACKGROUND

Hemodynamic assessment after volume challenge has been proposed as a way to identify heart failure with preserved ejection fraction. However, the normal hemodynamic response to a volume challenge and how age and sex affect this relationship remain unknown.

METHODS AND RESULTS

Sixty healthy subjects underwent right heart catheterization to measure age- and sex-related normative responses of pulmonary capillary wedge pressure and mean pulmonary arterial pressure to volume loading with rapid saline infusion (100-200 mL/min). Hemodynamic responses to saline infusion in heart failure with preserved ejection fraction (n=11) were then compared with those of healthy young (<50 years of age) and older (≥50 years of age) subjects. In healthy subjects, pulmonary capillary wedge pressure increased from 10±2 to 16±3 mm Hg after ~1 L and to 20±3 mm Hg after ~2 L of saline infusion. Older women displayed a steeper increase in pulmonary capillary wedge pressure relative to volume infused (16±4 mm Hg·L(-1)·m(2)) than the other 3 groups (P≤0.019). Saline infusion resulted in a greater increase in mean pulmonary arterial pressure relative to cardiac output in women compared with men regardless of age. Subjects with heart failure with preserved ejection fraction exhibited a steeper increase in pulmonary capillary wedge pressure relative to infused volume (25±12 mm Hg·L(-1)·m(2)) than healthy young and older subjects (P≤0.005).

CONCLUSIONS

Filling pressures rise significantly with volume loading, even in healthy volunteers. Older women and patients with heart failure with preserved ejection fraction exhibit the largest increases in pulmonary capillary wedge pressure and mean pulmonary arterial pressure.

Sex differences in arterial stiffness and ventricular-arterial interactions

OBJECTIVES

This study sought to assess sex differences in ventricular-arterial interactions.

BACKGROUND

Heart failure with preserved ejection fraction is more prevalent in women than in men, but the basis for this difference remains unclear.

METHODS

Echocardiography and arterial tonometry were performed to quantify arterial and ventricular stiffening and interaction in 461 participants without heart failure (189 men, age 67 ± 9 years; 272 women, age 65 ± 10 years). Aortic characteristic impedance (Z(c)), total arterial compliance (pulsatile load), and systemic vascular resistance index (steady load) were compared between men and women, and sex-specific multivariable regression analyses were performed to assess associations of these arterial parameters with diastolic dysfunction and ventricular-arterial coupling (effective arterial elastance/left ventricular end-systolic elastance [Ea/Ees]) after adjustment for potential confounders.

RESULTS

Z(c) was higher and total arterial compliance was lower in women, whereas systemic vascular resistance index was similar between sexes. In women but not men, higher log Z(c) was associated with mitral inflow E/A ratio (β ± SE: -0.17 ± 0.07), diastolic dysfunction (odds ratio: 7.8; 95% confidence interval: 2.0 to 30.2) and Ea/Ees (β ± SE: 0.13 ± 0.04) (p ≤ 0.01 for all). Similarly, total arterial compliance was associated with E/A ratio (β ± SE: 0.12 ± 0.04), diastolic dysfunction (odds ratio: 0.33; 95% confidence interval: 0.12 to 0.89), and Ea/Ees (β ± SE: -0.09 ± 0.03) in women only (p ≤ 0.03 for all). Systemic vascular resistance index was not associated with diastolic dysfunction or Ea/Ees.

CONCLUSIONS

Proximal aortic stiffness (Z(c)) is greater in women than men, and women may be more susceptible to the deleterious effects of greater pulsatile and early arterial load on diastolic function and ventricular-arterial interaction. This may contribute to the greater risk of heart failure with preserved ejection fraction in women.

Impact of gender on three-month outcome and left ventricular remodeling after transfemoral transcatheter aortic valve implantation

Transarterial aortic valve implantation (TAVI) is a promising method for the treatment of high-risk patients with aortic stenosis. Because gender differences are known in aortic stenosis, the aim of this study was to compare procedural and short-term outcomes, left ventricular remodeling, and inflammatory status after TAVI in men and women. One hundred consecutive patients (42 men, 58 women) who underwent transfemoral TAVI (CoreValve in 83%, SAPIEN in 17%) were prospectively analyzed. Aortic stenosis severity was higher in women (mean valve area 0.7 ± 0.3 vs 0.8 ± 0.2 cm(2)). Women had better ejection fractions, smaller end-diastolic and end-systolic diameters, and more concentric hypertrophy at baseline. There were no differences in device success rate (99%), 30-day total mortality (2.4% in men, 3.4% in women), stroke (2.4% in men, 1.7% in women), or pacemaker rate (26.2% in men, 15.5% in women). Periprocedural complications and 3-month outcome were not different between the genders. After TAVI, regression of hypertrophy occurred in men and women, but improvement of the ejection fraction was significant only in women. N-terminal pro-B-type natriuretic peptide decreased to similar levels in the 2 genders. C-reactive protein and interleukin-6, elevated at baseline more in men than in women, decreased after TAVI and normalized at 3 months only in women. In conclusion, women clinically benefit from TAVI to a degree similar to that of men. However, there are gender differences involving the recovery response of the left ventricle after TAVI.

Effect of antihypertensive therapy on ventricular-arterial mechanics, coupling, and efficiency

AIMS

To investigate the effect of antihypertensive therapy on ventricular-arterial mechanics, coupling, and efficiency in early-stage hypertension.

METHODS AND RESULTS

We studied 527 participants from two clinical trials assessing the effect of blood pressure lowering on diastolic function. Participants were aged ≥45 years with early-stage hypertension, no heart failure, ejection fraction (EF) ≥50%, and diastolic dysfunction using Doppler echocardiography. Effective arterial afterload and its components were assessed along with measures of left ventricular (LV) structure and function prior to and after 24-38 weeks of antihypertensive therapy. Systolic blood pressure decreased from 154 ± 18 to 137 ± 15 mmHg at follow-up. Blood pressure reduction was associated with decreases in ventricular and arterial stiffness, improvements in systemic arterial compliance and resistance, enhanced LV ejection, and reduction in cardiac work (all P < 0.001). Changes in Ea/Ees ratio were inversely correlated with those in EF (r = -0.25; P < 0.001), stroke work index (r = -0.13; P = 0.007), and LV efficiency (r = -0.98; P < 0.001); and directly related to changes in mitral E/e' (r = 0.12; P = 0.01). Adjusting for age and blood pressure change, women and obese individuals had less enhancement in ventricular-arterial coupling and efficiency compared with men and non-obese individuals (P = 0.04 and 0.007, respectively).

CONCLUSION

Antihypertensive therapy reduces arterial and ventricular stiffness, enhances ventricular-arterial coupling, reduces cardiac work, and improves LV efficiency, systolic, and diastolic function. Attenuated responses in women and among obese subjects suggest that structure-function changes may be less reversible in these groups, possibly explaining their greater susceptibility to ultimately develop heart failure.