Left ventricular diastolic function assessment by tissue Doppler echocardiography in relation to hormonal replacement therapy in postmenopausal women with diastolic dysfunction

The impact of female sex hormones on cardiovascular disease: from mechanisms to hormone therapy

Cardiovascular disease remains the leading cause of mortality in women, yet it has not raised the awareness from the public. The pathogenesis of cardiovascular disease differs significantly between females and males concerning the effect of sex hormones. Estrogen and progestogen impact cardiovascular system through genomic and non-genomic effects. Before menopause, cardiovascular protective effects of estrogens have been well described. Progestogens were often used in combination with estrogens in hormone therapy. Fluctuations in sex hormone levels, particularly estrogen deficiency, were considered the specific risk factor in women's cardiovascular disease. However, considerable heterogeneity in the impact of hormone therapy was observed in clinical trials. The heterogeneity is likely closely associated with factors such as the initial time, administration route, dosage, and formulation of hormone therapy. This review will delve into the pathogenesis and hormone therapy, summarizing the effect of female sex hormones on hypertension, pre-eclampsia, coronary heart disease, heart failure with preserved ejection fraction, and cardiovascular risk factors specific to women.

Cardiac Mechanics in Altered Hormonal States as a Surrogate for Understanding the Effects of Transgender Hormone Therapy

Transgender individuals are increasingly seeking the care of physicians to physically transition to their self-identified gender identity. Gender-affirming hormone therapy (GAHT) has significant endocrine effects which may have cardiovascular consequences, and cardiovascular disease in transgender individuals is a growing area of study. The effects of GAHT on cardiac mechanics have yet to be characterized, but there is existing literature regarding changes to cardiac mechanics in similar altered hormonal states. We reviewed this literature, with a focus on echocardiographic findings. We found variable results between studies of different methodologies. These include findings that supraphysiological levels of testosterone may impair cardiac mechanics, whereas estrogen-containing hormonal replacement therapy may improve diastolic echocardiographic parameters. In summary, there are alterations to echocardiographic parameters in altered endocrine states related to exogenous testosterone and estrogen, in a manner that is likely dose-dependent. Encouragingly, the studies we reviewed did not suggest that hormonal changes within physiologic ranges would detrimentally affect echocardiographic parameters of systolic and diastolic function. Future research into the cardiovascular effects of long-term GAHT is warranted to safely guide the longitudinal treatment of transgender individuals.

Circadian regulation of genetic and hormonal risk factors of cardiovascular disease in women

Cardiovascular disease is the leading cause of morbidity and mortality worldwide. However, sex differences can impact differently the etiology and outcome of cardiovascular disease when comparing men and women. Women have unique genetic and hormonal risk factors that can be associated with the development of cardiovascular diseases. Furthermore, certain phenotypes of cardiovascular diseases are more prevalent to women. Molecular clocks control circadian rhythms of different physiological systems in our body, including the cardiovascular system. Increased evidence in recent years points to a link between cardiovascular disease and regulation by circadian rhythms. However, the difference between circadian regulation of cardiovascular disease in women and men is poorly understood. In this review, we highlight the recent advances in circadian-regulated cardiovascular diseases with a specific focus on the pathogenesis of heart disease in women. Understanding circadian-regulated pathways and sex-specific differences between men and women may contribute to better diagnosis and development of sex-targeted interventions to better treat cardiovascular diseases.

Sex differences in heart failure with preserved ejection fraction: From traditional risk factors to sex-specific risk factors

Heart failure with preserved ejection fraction has a higher prevalence in women versus men. There are several proposed mechanisms to explain this sex discrepancy including differences in cardiovascular adaptation to comorbidities and potential underlying etiologic mechanisms. In this review, we summarize sex differences in traditional risk factors, such as obesity, diabetes, hypertension, and coronary artery disease, which contribute to the development of heart failure with preserved ejection fraction in women. Furthermore, we explore female-specific risk factors, such as sex hormones, adverse pregnancy outcomes, and other reproductive factors, which may explain the predominance of heart failure with preserved ejection fraction in women. Beyond sex differences in risk factors, there are also significant sex differences in outcomes with women reporting lower quality of life but overall better survival versus men. Finally, while treatment options for patients with heart failure with preserved ejection fraction are still limited, sex differences have also been reported for the available therapies, with suggestion of preferential benefit of specific heart failure with preserved ejection fraction therapies in women. Further work is required to better understand sex differences in heart failure with preserved ejection fraction, including deeper understanding of pathophysiological mechanisms, derivation of more accurate risk stratification models, and increased representation of women in clinical trials.

Sex Differences in Molecular Mechanisms of Cardiovascular Aging

Cardiovascular disease (CVD) is still the leading cause of illness and death in the Western world. Cardiovascular aging is a progressive modification occurring in cardiac and vascular morphology and physiology where increased endothelial dysfunction and arterial stiffness are observed, generally accompanied by increased systolic blood pressure and augmented pulse pressure. The effects of biological sex on cardiovascular pathophysiology have long been known. The incidence of hypertension is higher in men, and it increases in postmenopausal women. Premenopausal women are protected from CVD compared with age-matched men and this protective effect is lost with menopause, suggesting that sex-hormones influence blood pressure regulation. In parallel, the heart progressively remodels over the course of life and the pattern of cardiac remodeling also differs between the sexes. Lower autonomic tone, reduced baroreceptor response, and greater vascular function are observed in premenopausal women than men of similar age. However, postmenopausal women have stiffer arteries than their male counterparts. The biological mechanisms responsible for sex-related differences observed in cardiovascular aging are being unraveled over the last several decades. This review focuses on molecular mechanisms underlying the sex-differences of CVD in aging.

Age-related sex differences in the outcomes of patients with hypertrophic cardiomyopathy

BACKGROUND

We aimed to clarify the sex differences in various cardiovascular and non-cardiovascular outcomes, and to investigate whether sex differences in outcomes are affected by age in hypertrophic cardiomyopathy (HCM).

METHODS

A cohort of 835 patients with HCM initially evaluated during 2007-2019 were followed for a median of 6.4 years. Study outcomes were all-cause death, cardiovascular and non-cardiovascular death, sudden cardiac death (SCD)/SCD equivalent events, heart failure (HF) events, and the composite cardiovascular outcome including cardiovascular death, SCD/SCD equivalent events, admission for HF, and heart transplantation.

RESULTS

Women were 5 years older (women 59.9±13.5 vs. men 54.9±11.4 years), had worse dyspnea, and greater left ventricular (LV) diastolic dysfunction and obstructive physiology at presentation. Women compared to men had higher all-cause mortality and cardiovascular event rates, driven by more cardiovascular deaths and heart failure (HF) events. Conversely, non-cardiovascular mortality was not different between the sexes. Female sex was independently associated with all-cause death (HR 1.88, 95% CI 1.11-3.20) and composite cardiovascular events (HR 3.60, 95% CI 2.00-6.49), independent of age, body mass index, New York Heart Association class, SCD risk score, and LV ejection fraction. When stratified by the age of 60, sex differences were not significant at <60 years; however, at ≥60 years, women had worse LV diastolic function, greater obstructive physiology, as well as worse survival and composite cardiovascular outcomes. Sex differences in outcomes remained consistent after propensity score matching for age and other clinical characteristics.

CONCLUSIONS

Women with HCM have worse cardiovascular prognosis than men, driven by higher cardiovascular mortality and HF events. The negative impact of female sex on cardiac function and cardiovascular outcome became prominent at age ≥60 years, suggesting age-related sex differences in the prognosis of HCM.

Deletion of P21-activated kinase-1 induces age-dependent increased visceral adiposity and cardiac dysfunction in female mice

It is known that there is an age-related progression in diastolic dysfunction, especially prevalent in postmenopausal women, who develop heart failure with preserved ejection fraction (HFpEF, EF > 50%). Mechanisms and therapies are poorly understood, but there are strong correlations between obesity and HFpEF. We have tested the hypothesis that P21-activated kinase-1 (PAK1) preserves cardiac function and adipose tissue homeostasis during aging in female mice. Previous demonstrations in male mice by our lab that PAK1 activity confers cardio-protection against different stresses formed the rationale for this hypothesis. Our studies compared young (3-6 months) and middle-aged (12-15 months) female and male PAK1 knock-out mice (PAK1-/-) and wild-type (WT) equivalent. Female WT mice exhibited increased cardiac PAK1 abundance during aging. By echocardiography, compared to young WT female mice, middle-aged WT female mice showed enlargement of the left atrium as well as thickening of posterior wall and increased left ventricular mass; however, all contraction and relaxation parameters were preserved during aging. Compared to WT controls, middle-aged PAK1-/- female mice demonstrated worsening of cardiac function involving a greater enlargement of the left atrium, ventricular hypertrophy, and diastolic dysfunction. Moreover, with aging PAK1-/- female mice, unlike male PAK1-/- mice, exhibited increased adiposity with increased accumulation of visceral adipose tissue. Our data provide evidence for the significance of PAK1 signaling as an element in the preservation of cardiac function and adipose tissue homeostasis in females during aging.

Estrogen and calcium handling proteins: new discoveries and mechanisms in cardiovascular diseases

Estrogen deficiency is considered to be an important factor leading to cardiovascular diseases (CVDs). Indeed, the prevalence of CVDs in postmenopausal women exceeds that of premenopausal women and men of the same age. Recent research findings provide evidence that estrogen plays a pivotal role in the regulation of calcium homeostasis and therefore fine-tunes normal cardiomyocyte contraction and relaxation processes. Disruption of calcium homeostasis is closely associated with the pathological mechanism of CVDs. Thus, this paper maps out and summarizes the effects and mechanisms of estrogen on calcium handling proteins in cardiac myocytes, including L-type Ca²⁺ channel, the sarcoplasmic reticulum Ca²⁺ release channel named ryanodine receptor, sarco(endo)plasmic reticulum Ca²⁺-ATPase, and sodium-calcium exchanger. In so doing, we provide theoretical and experimental evidence for the successful design of estrogen-based prevention and treatment therapies for CVDs.

Female Heart Health: Is GPER the Missing Link?

The G Protein-Coupled Estrogen Receptor (GPER) is a novel membrane-bound receptor that mediates non-genomic actions of the primary female sex hormone 17β-estradiol. Studies over the past two decades have elucidated the beneficial actions of this receptor in a number of cardiometabolic diseases. This review will focus specifically on the cardiac actions of GPER, since this receptor is expressed in cardiomyocytes as well as other cells within the heart and most likely contributes to estrogen-induced cardioprotection. Studies outlining the impact of GPER on diastolic function, mitochondrial function, left ventricular stiffness, calcium dynamics, cardiac inflammation, and aortic distensibility are discussed. In addition, recent data using genetic mouse models with global or cardiomyocyte-specific GPER gene deletion are highlighted. Since estrogen loss due to menopause in combination with chronological aging contributes to unique aspects of cardiac dysfunction in women, this receptor may provide novel therapeutic effects. While clinical studies are still required to fully understand the potential for pharmacological targeting of this receptor in postmenopausal women, this review will summarize the evidence gathered thus far on its likely beneficial effects.

The Role of Estrogen in Cardiac Metabolism and Diastolic Function

Heart failure with preserved ejection fraction (HFpEF) has similar prevalence and prognosis as HF with reduced EF, but there is no approved treatment for HFpEF. HFpEF is common in postmenopausal women, which suggests that the absence of estrogen (E2) plays a role in its pathophysiology. With the country's growing elderly population, the prevalence of HFpEF is rapidly increasing. This has triggered a renewed urgency in finding novel approaches to preventing and slowing the progression of HFpEF. In this review, we address the role of E2 in left ventricular diastolic function and how it impacts women with HFpEF as well as animal models. We also discuss the primary potential mechanisms that represent critical nodes in the mechanistic pathways of HFpEF and how new treatments could be developed to target those mechanisms.

The cardiovascular effects of premature ovarian failure

BACKGROUND

Previous studies have shown that cardiovascular risk is increased in premature ovarian failure (POF). To determine the effects of POF on different parameters of cardiovascular health, we investigated the relationship between POF and circulating endothelial progenitor cells (EPC), endothelial function, carotid intima media thickness (CIMT) and left ventricular diastolic function.

METHODS

We compared 23 female POF patients (mean age; 37.8 ± 10.8 years) with 20 gender and age-matched healthy controls. Circulating CD133(+)/34(+) and CD34(+)/KDR(+) EPCs were determined by using flow-cytometry. Ultrasound assessment of endothelial function by brachial artery flow-mediated dilatation (FMD) and CIMT was made. Left ventricular systolic and diastolic function was assessed by standard 2D and M-mode echocardiography and tissue Doppler velocities.

RESULTS

Brachial artery FMD was significantly impaired in patients with POF compared with CG (6.3 ± 1.9% vs 10.4 ± 3.7%, p<0.05). Furthermore, circulating EPCs were lower among patients with POF compared to controls for CD133(+)/34(+) and CD34(+)/KDR(+) cells (p<0.05). There was a significant correlation between serum estradiol levels and EPC number (CD 133+/34+) (r=0.329, p<0.05). POF patients had increased CIMT compared to controls (0.67 ± 0.17 vs 0.43 ± 0.10, p<0.05). When diastolic functions were assessed, patients with POF had lower Epeak, Apeak and mitral CP and higher DT and IVRT (p<0.05, respectively).

CONCLUSION

Our findings indicate that endothelial function as well as circulating EPCs, CIMT and diastolic function are significantly affected in young women with POF which may have an adverse long-term effect on cardiovascular prognosis.

The effects of hormone replacement therapy on myocardial performance in early postmenopausal women

OBJECTIVES

The results of the studies in which the effect of hormone replacement therapy (HRT) on cardiac function have been evaluated are rather disputable. In these studies, cardiac function was evaluated with conventional echocardiographic methods. This study was planned in order to investigate the effects of HRT on myocardial velocities and myocardial performance index (MPI) in healthy early postmenopausal women.

METHOD

In a prospective, controlled study, 60 healthy postmenopausal women were assigned to two groups (32 in the HRT group and 28 in the control group). After conventional echocardiographic parameters were measured, tissue Doppler echocardiography recordings were obtained from the mitral and tricuspid annulus. Systolic myocardial velocity (Sm), early and late diastolic myocardial velocities (Em and Am) and time intervals were measured and MPI was calculated. Then the symptom-limited exercise stress test using the Bruce protocol was performed. After 3 and 6 months of HRT (oral 0.625 mg conjugated estrogen + 2.5 mg medroxyprogesterone acetate/day), the same examinations were repeated. The effects of HRT on myocardial velocities, MPI and exercise time were evaluated at the 3rd and 6th months.

RESULTS

The parameters of the control group remained statistically unchanged during the study. HRT did not have any effect on segmental and mean left ventricular (LV) Sm or right ventricular (RV) Sm. However, LV Em/Am and RV Em/Am ratios significantly increased at the 6th month of HRT, and LV and RV MPI values were observed to decrease significantly as compared to basal values. Additionally, a significant increase was observed in exercise duration and metabolic equivalent values after 3 months of HRT, and this increase continued at the 6th month as well. The favorable changes in all parameters in the HRT group were significantly different from those of the control group.

CONCLUSION

Data obtained in this study suggest that HRT is not only effective for treating menopausal complaints but also increases cardiovascular performance by improving especially diastolic functions in early postmenopausal women.

Effect of lifestyle factors and hormone therapy on heart function by serial echocardiography in postmenopausal women

BACKGROUND

There is conflicting information on the effects of oestrogen on the heart in women, especially those using postmenopausal hormone therapy. Whilst some studies reported a beneficial effect, others showed adverse outcomes. The interplay of lifestyle factors and type/timing of therapy remains to be clarified.

AIM

The aim of this study was to determine the effects of lifestyle and hormone therapy on heart function and structure in postmenopausal women.

METHOD

As part of a large longitudinal study of women randomly recruited from an urban population, the study assessed 410 suitable women by echocardiography in Year 1 and Year 5 of the study by two independent cardiologists.

RESULTS

In lifestyle characteristics, the difference in age and body mass (as markers of cardiovascular risk) was in favour of never-users versus hormone therapy-users. Using an arbitrary cut-off > or =15% change for an effect, we found lifestyle factors had minimal effect on the two measured parameters - ejection fraction, left ventricular mass. Effects of hormone therapy were variable and mixed; greatest effect was found for an 'early start' of hormone therapy with oestrogen-only preparation - the risk of reduced ejection fraction was decreased [hazard ratio (HR) 0.42, confidence interval = 0.17-1.03, P = 0.06] and risk of increased left ventricular mass was increased (HR 2.21, 1.09-4.49, P = 0.03).

CONCLUSION

Our findings add to the evidence that oestrogen given to postmenopausal women has a mixed effect on the heart, with effect best shown when started early.