Sex differences in left ventricular remodelling, myocardial fibrosis and mortality after aortic valve replacement

Clinical and imaging characteristics of patients with cardiac amyloidosis- a single center observational study

Amyloidosis is a disease characterized by the deposition of protein fibrils. Cardiac involvement is a significant factor in determining prognosis. This study aimed to examine the clinical profile, outcomes, and long-term mortality rates in patients with transthyretin (ATTR) and amyloid light-chain (AL) amyloidosis. The retrospective cohort study included 94 patients with amyloidosis (69 with AL and 25 with ATTR amyloidosis) diagnosed between 2010 and 2022. The study involved multimodality imaging (ECG, echocardiography and cardiac magnetic resonance (CMR) data and survival analyses. Patients with ATTR amyloidosis were older and had a higher proportion of males compared to those with AL amyloidosis. Cardiac involvement was more prevalent in the ATTR group, including atrial fibrillation (AF), while pleural and pericardial effusion were more frequent in the AL group. Biomarkers such as NT-proBNP and troponin T were significantly elevated in both groups and were associated with all-cause mortality only in univariate analyses. CMR data, especially typical late gadolinium enhancement (LGE) was not associated with increased mortality, while pleural effusion and left atrial dilatation on echocardiography were identified as powerful predictors of mortality. In conclusion, both AL and ATTR amyloidosis exhibited poor outcomes. Cardiac involvement, particularly dilated left atrium and pleural effusion on echocardiography were associated with an increased risk of mortality, while typical LGE on CMR was not.

Female showed favorable left ventricle hypertrophy regression during post-TAVR follow-up

Transcatheter aortic valve replacement (TAVR) is a well-established procedure using a catheter-introduced valve prosthesis for patients with severe aortic stenosis (AS). This retrospective study investigated sex-related differences in pre- and post-TAVR clinical and hemodynamic outcomes and analyzed data of the first 100 cases at Kaohsiung Medical University Chung-Ho Memorial Hospital (KMUH) between December 2013 and December 2021. Baseline characteristics, procedural outcomes, mortality rates, and echocardiographic parameters were analyzed and compared between sexes. Among the 100 patients, male (46%) and female (54%) were of similar age (mean age, male 86.0 years vs. female 84.5 years) and of the same severity of AS (mean pressure gradient, male 47.5 mmHg vs. female 45.7 mmHg) at the time receiving the TAVR procedure. Women had smaller aortic valve areas calculated by continuity equation (0.8 ± 0.3 cm2 vs. 0.7 ± 0.2 cm2, p < 0.001). In addition, women had better left ventricle ejection fraction (59.6 ± 14.0% vs. men 54.7 ± 17.2%, p < 0.01). In the post-TAVR follow-up, regression of left ventricle mass and dimension was better in women than in men. None of the patient died within 30 days after the procedure, and women tended to have a more favorable survival than men (2-year mortality and overall mortality rate in 8.3 year, women 9.1% and 22.2% vs. men 22.2% and 34.8%; p = 0.6385 and 0.1277, respectively). In conclusion, the sex-based difference in post-TAVR regression of LV remodeling suggests a need for sex-based evaluation for patients with severe AS and their post TAVR follow-up.

Regional variation and temporal trends in transcatheter and surgical aortic valve replacement in Switzerland: A population-based small area analysis

BACKGROUND

Aortic valve stenosis (AS) is the most common valvular heart disease and if severe, is treated with either transcatheter (TAVR) or surgical aortic valve replacement (SAVR). We assessed temporal trends and regional variation of these interventions in Switzerland and examined potential determinants of geographic variation.

METHODS

We conducted a population-based analysis using patient discharge data from all Swiss public and private acute care hospitals from 2013 to 2018. We generated hospital service areas (HSAs) based on patient flows for TAVR. We calculated age-standardized mean procedure rates and variation indices (extremal quotient [EQ] and systematic component of variation [SCV]). Using multilevel regression, we calculated the influence of calendar year and regional demographics, socioeconomic factors (language, insurance status), burden of disease, and number of cardiologists/cardiovascular surgeons on geographic variation.

RESULTS

Overall, 8074 TAVR and 11,825 SAVR procedures were performed in 8 HSAs from 2013 to 2018. Whereas the age-/sex-standardized rate of TAVR increased from 12 to 22 procedures/100,000 persons, the SAVR rate decreased from 33 to 24 procedures during this period. After full adjustment, the predicted TAVR and SAVR rates varied from 12 to 22 and 20 to 35 per 100,000 persons across HSAs, respectively. The regional procedure variation was low to moderate over time, with a low overall variation in TAVR (EQ 1.9, SCV 3.9) and SAVR (EQ 1.6, SCV 2.2). In multilevel regression, TAVR rates increased annually by 10% and SAVR rates decreased by 5%. Determinants of higher TAVR rates were older age, male sex, living in a German speaking area, and higher burden of disease. A higher proportion of (semi)private insurance was also associated with higher TAVR and lower SAVR rates. After full adjustment, 10.6% of the variance in TAVR and 18.4% of the variance in SAVR remained unexplained. Most variance in TAVR and SAVR rates was explained by language region and insurance status.

CONCLUSION

The geographic variation in TAVR and SAVR rates was low to moderate across Swiss regions and largely explained by differences in regional demographics and socioeconomic factors. The use of TAVR increased at the expense of SAVR over time.

Is there a role for cardiovascular magnetic resonance imaging in the assessment of biological aortic valves?

Patients with biological aortic valves (following either surgical aortic valve replacement [SAVR] or trans catheter aortic valve implantation [TAVI]) require lifelong follow-up with an imaging modality to assess prosthetic valve function and dysfunction. Echocardiography is currently the first-line imaging modality to assess biological aortic valves. In this review, we discuss the potential role of cardiac magnetic resonance imaging (CMR) as an additional imaging modality in situations of inconclusive or equivocal echocardiography. Planimetry of the prosthetic orifice can theoretically be measured, as well as the effective orifice area, with potential limitations, such as CMR valve-related artefacts and calcifications in degenerated prostheses. The true benefit of CMR is its ability to accurately quantify aortic regurgitation (paravalvular and intra-valvular) with a direct and reproducible method independent of regurgitant jet morphology to accurately assess reverse remodelling and non-invasively detect focal and interstitial diffuse myocardial fibrosis. Following SAVR or TAVI for aortic stenosis, interstitial diffuse fibrosis can regress, accompanied by structural and functional improvement that CMR can accurately assess.

Sex Differences in Clinical Outcomes after Aortic Valve Intervention for Isolated Severe Aortic Stenosis

There are known pathophysiologic and clinical differences according to sex in patients with aortic stenosis (AS). To evaluate if these differences persist after valve replacement, we conducted an observational study including 451 patients with symptomatic AS who survived aortic valve intervention (AVI) in two centers. Clinical data and mortality were evaluated at a mean follow-up of 5 years. 56% of patients were women. At baseline, women were older (80.6 vs. 78 years, p = 0.013), presented higher mean gradient (48 vs. 45 mmHg, p = 0.023), lower aortic valve area (0.70 vs. 0.74 cm2, p = 0.002) and higher systolic pulmonary artery pressure (36 vs. 33 mmHg, p = 0.016). They underwent percutaneous aortic valve replacement more frequently than men (47 vs. 35.9%, p = 0.017). At 5 years follow-up, women required more admissions due to heart failure (23 vs. 9%, p = 0.046) but they did not present higher cardiovascular nor overall mortality (27.7% vs. 29.8%, p = 0.741; 11.1 vs. 10.1%, p = 0.619, respectively). Female sex was an independent predictor of heart failure hospitalization at follow-up (HR 95% 1.16-4.22, p = 0.016). Women undergo AVI at a more advanced stage than men, resulting in a higher frequency of readmissions due to heart failure during the follow-up period, but not in higher mortality.

Impact of aortic valve stenosis on myocardial deformation in different left ventricular levels: A three-dimensional speckle tracking echocardiography study

BACKGROUND

Global systolic left ventricular (LV) myocardial function progressively declines as degenerative aortic valve stenosis (AS) progresses. Whether this results in uniformly distributed deformation changes from base to apex has not been investigated.

METHODS

Eighty-five AS patients underwent three-dimensional (3D) echocardiography in this cross-sectional study. Patients were grouped by peak jet velocity into mild (n = 32), moderate (n = 31), and severe (n = 22) AS. 3D speckle tracking derived strain, rotation, twist, and torsion were obtained to assess global LV function and myocardial function at the apical, mid, and basal levels.

RESULTS

Global longitudinal strain (GLS) was lower in patients with severe AS (-16.1 ± 2.4% in mild, -15.5 ± 2.5% in moderate, and -13.5 ± 3.0% in severe AS [all p < .01]). Peak basal and mid longitudinal strain (LS), basal rotation and twist from apical to basal level followed the same pattern, while peak apical LS was higher in moderate AS compared to severe AS (all p < .05). In multivariate analyses, lower GLS was particularly associated with male sex, higher body mass index and peak aortic jet velocity, lower basal LS with higher filling pressure (E/e') and LV mass, lower mid LS with higher RWT and presence of AS symptoms, and lower apical LS with male sex and higher systolic blood pressure, respectively (all p < .05).

CONCLUSION

Using 3D speckle tracking echocardiography reveals regional and global changes in LV mechanics in AS related to the severity of AS, LV remodeling and presence of cardiovascular risk factors.

Soluble ST2 levels are related to replacement myocardial fibrosis in severe aortic stenosis

INTRODUCTION AND OBJECTIVES

Patients with aortic stenosis (AS) exhibit left ventricular (LV) remodeling and replacement myocardial fibrosis (RMF). Whether sST2 is associated with RMF measured by cardiac magnetic resonance and with sex remains unknown.

METHODS

We recruited 79 consecutive patients (73.0 [68.0-78.0] years; 61% men) with severe isolated AS underdoing valve replacement. RMF was identified and quantified by late gadolinium enhancement (LGE). Serum sST2 levels were determined.

RESULTS

RMF was associated with higher circulating sST2 levels, LV hypertrophy and dilation, and lower LV ejection fraction. All patients with LV dysfunction had RMF. Circulating levels of sST2 ≥ 28.8 ng/mL were associated with RMF and greater LV hypertrophy. LGE mass was correlated with LV remodeling and sST2. Of note, sST2 levels were also associated with the RMF pattern, being higher in midwall than in subendocardial fibrosis. Multivariate analyses showed that only LV ejection fraction and sST2 levels were associated with RMF. Moreover, men had higher levels of sST2 and RMF. RMF was associated with higher LV dilation and hypertrophy only in men and was correlated with LGE mass.

CONCLUSIONS

SST2 was an independent factor for RMF in patients with severe isolated AS. The presence of RMF was predicted by sST2 ≥ 28.2 ng/mL, and was associated with greater LV hypertrophy. sST2 expression and clinical associations may be sex-specific.

Population study of sex-based outcomes after surgical aortic valve replacement

Background

Surgical aortic valve replacement (SAVR) is a key strategy for the treatment of aortic valve disease. However, studies have involved primarily male patients, and whether the benefits of this approach can be extrapolated to female patients is unclear.

Methods

Clinical and administrative datasets for 12,207 patients undergoing isolated SAVR in Ontario from 2008 to 2019 were linked. Male and female patients were balanced using inverse probability treatment weighting. Mortality, endocarditis, and major hemorrhagic and thrombotic events, as well as 2 composite outcomes-major adverse cerebral and cardiovascular events (MACCE) and patient-derived adverse cardiovascular and noncardiovascular events (PACE)-and their component events, were compared in the weighted groups with a stratified log-rank test.

Results

A total of 7485 male patients and 4722 female patients were included in the study. Median follow-up was 5.2 years in both sexes. All-cause mortality did not differ between sexes (hazard ratio [HR] 0.949 [95% confidence interval {CI} 0.851-1.059]). Male sex was associated with an increased risk of new-onset dialysis (HR 0.689 [95% CI 0.488-0.974]). Female sex was associated with a significantly increased risk of both new-onset heart failure (HR 1.211 [95% CI 1.051-1.394], P = 0.0081) and heart failure hospitalization (HR 1.200 [95% CI 1.036-1.390], P = 0.015). No statistically significant differences were seen in any of the other secondary outcomes between sexes.

Conclusions

This population health study demonstrated that survival did not differ between male and female patients undergoing SAVR. Significant sex-related differences were found in the risk of heart failure and new-onset dialysis, but these findings should be considered exploratory and require further study.

Non-invasive Imaging in Women With Heart Failure - Diagnosis and Insights Into Disease Mechanisms

PURPOSE OF REVIEW

To summarise the role of different imaging techniques for diagnosis and investigation of heart failure in women.

RECENT FINDINGS

Although sex differences in heart failure are well recognised, and the scope of imaging techniques is expanding, there are currently no specific guidelines for imaging of heart failure in women. Diagnosis and stratification of heart failure is generally performed first line using transthoracic echocardiography. Understanding the aetiology of heart failure is central to ongoing management, and with non-ischaemic causes more common in women, a multimodality approach is generally required using advanced imaging techniques including cardiovascular magnetic resonance imaging, nuclear imaging techniques, and cardiac computed tomography. There are specific considerations for imaging in women including radiation risks and challenges during pregnancy, highlighting the clear unmet need for cardiology and imaging societies to provide imaging guidelines specifically for women with heart failure.

Cardiac Fibrosis in the Pressure Overloaded Left and Right Ventricle as a Therapeutic Target

Myocardial fibrosis is a remodeling process of the extracellular matrix (ECM) following cardiac stress. "Replacement fibrosis" is a term used to describe wound healing in the acute phase of an injury, such as myocardial infarction. In striking contrast, ECM remodeling following chronic pressure overload insidiously develops over time as "reactive fibrosis" leading to diffuse interstitial and perivascular collagen deposition that continuously perturbs the function of the left (L) or the right ventricle (RV). Examples for pressure-overload conditions resulting in reactive fibrosis in the LV are systemic hypertension or aortic stenosis, whereas pulmonary arterial hypertension (PAH) or congenital heart disease with right sided obstructive lesions such as pulmonary stenosis result in RV reactive fibrosis. In-depth phenotyping of cardiac fibrosis has made it increasingly clear that both forms, replacement and reactive fibrosis co-exist in various etiologies of heart failure. While the role of fibrosis in the pathogenesis of RV heart failure needs further assessment, reactive fibrosis in the LV is a pathological hallmark of adverse cardiac remodeling that is correlated with or potentially might even drive both development and progression of heart failure (HF). Further, LV reactive fibrosis predicts adverse outcome in various myocardial diseases and contributes to arrhythmias. The ability to effectively block pathological ECM remodeling of the LV is therefore an important medical need. At a cellular level, the cardiac fibroblast takes center stage in reactive fibrotic remodeling of the heart. Activation and proliferation of endogenous fibroblast populations are the major source of synthesis, secretion, and deposition of collagens in response to a variety of stimuli. Enzymes residing in the ECM are responsible for collagen maturation and cross-linking. Highly cross-linked type I collagen stiffens the ventricles and predominates over more elastic type III collagen in pressure-overloaded conditions. Research has attempted to identify pro-fibrotic drivers causing fibrotic remodeling. Single key factors such as Transforming Growth Factor β (TGFβ) have been described and subsequently targeted to test their usefulness in inhibiting fibrosis in cultured fibroblasts of the ventricles, and in animal models of cardiac fibrosis. More recently, modulation of phenotypic behaviors like inhibition of proliferating fibroblasts has emerged as a strategy to reduce pathogenic cardiac fibroblast numbers in the heart. Some studies targeting LV reactive fibrosis as outlined above have successfully led to improvements of cardiac structure and function in relevant animal models. For the RV, fibrosis research is needed to better understand the evolution and roles of fibrosis in RV failure. RV fibrosis is seen as an integral part of RV remodeling and presents at varying degrees in patients with PAH and animal models replicating the disease of RV afterload. The extent to which ECM remodeling impacts RV function and thus patient survival is less clear. In this review, we describe differences as well as common characteristics and key players in ECM remodeling of the LV vs. the RV in response to pressure overload. We review pre-clinical studies assessing the effect of anti-fibrotic drug candidates on LV and RV function and their premise for clinical testing. Finally, we discuss the mode of action, safety and efficacy of anti-fibrotic drugs currently tested for the treatment of left HF in clinical trials, which might guide development of new approaches to target right heart failure. We touch upon important considerations and knowledge gaps to be addressed for future clinical testing of anti-fibrotic cardiac therapies.

Association of Myocardial Fibrosis and Stroke Volume by Cardiovascular Magnetic Resonance in Patients With Severe Aortic Stenosis With Outcome After Valve Replacement: The British Society of Cardiovascular Magnetic Resonance AS700 Study

Importance

Low-flow severe aortic stenosis (AS) has higher mortality than severe AS with normal flow. The conventional definition of low-flow AS is an indexed stroke volume (SVi) by echocardiography less than 35 mL/m2. Cardiovascular magnetic resonance (CMR) is the reference standard for quantifying left ventricular volumes and function from which SVi by CMR can be derived.

Objective

To determine the association of left ventricular SVi by CMR with myocardial remodeling and survival among patients with severe AS after valve replacement.

Design, Setting, and Participants

This multicenter longitudinal cohort study was conducted between January 2003 and May 2015 across 6 UK cardiothoracic centers. Patients with severe AS listed for either surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) were included. Patients underwent preprocedural echocardiography and CMR. Patients were stratified by echocardiography-derived aortic valve mean and/or peak gradient and SVi by CMR into 4 AS endotypes: low-flow, low-gradient AS; low-flow, high-gradient AS; normal-flow, low-gradient AS; and normal-flow, high-gradient AS. Patients were observed for a median of 3.6 years. Data were analyzed from September to November 2021.

Exposures

SAVR or TAVR.

Main Outcomes and Measures

All-cause and cardiovascular (CV) mortality after aortic valve intervention.

Results

Of 674 included patients, 425 (63.1%) were male, and the median (IQR) age was 75 (66-80) years. The median (IQR) aortic valve area index was 0.4 (0.3-0.4) cm2/m2. Patients with low-flow AS endotypes (low gradient and high gradient) had lower left ventricular ejection fraction, mass, and wall thickness and increased all-cause and CV mortality than patients with normal-flow AS (all-cause mortality: hazard ratio [HR], 2.08; 95% CI, 1.37-3.14; P < .001; CV mortality: HR, 3.06; 95% CI, 1.79-5.25; P < .001). CV mortality was independently associated with lower SVi (HR, 1.64; 95% CI, 1.08-2.50; P = .04), age (HR, 2.54; 95% CI, 1.29-5.01; P = .001), and higher quantity of late gadolinium enhancement (HR, 2.93; 95% CI, 1.68-5.09; P < .001). CV mortality hazard increased more rapidly in those with an SVI less than 45 mL/m2. SVi by CMR was independently associated with age, atrial fibrillation, focal scar (by late gadolinium enhancement), and parameters of cardiac remodeling (left ventricular mass and left atrial volume).

Conclusions and Relevance

In this cohort study, SVi by CMR was associated with CV mortality after aortic valve replacement, independent of age, focal scar, and ejection fraction. The unique capability of CMR to quantify myocardial scar, combined with other prognostically important imaging biomarkers, such as SVi by CMR, may enable comprehensive stratification of postoperative risk in patients with severe symptomatic AS.

Sex differences in aortopathy and valve diseases among patients undergoing cardiac surgery

BACKGROUND

We aimed to study sex differences in aortopathy and valve disease among patients undergoing aortic valve replacement and/or surgery for ascending aortic aneurysm, and assess whether differences are specific for patients with bicuspid (BAV) compared to patients with tricuspid aortic valve (TAV).

METHODS

We used a single-center and observational cohort including 1,045 patients undergoing elective open-heart surgery for aortic valve disease and/or ascending aortic aneurysm at the Karolinska Hospital (Sweden).

RESULTS

Women (33.0%) were older than men (mean [SD]; 67.9 [11] years vs 62.5 [13] years for men; P < 0.001). No significant sex difference in prevalence of ascending aortic aneurysm was found according to absolute measures (P = 0.19), however, women had a greater dilation of the ascending aorta when normalized for body surface area (mean [SD], 21.8 [6.3] mm/m² vs 19.3 [4.4] mm/m² for men; P < 0.001). Among the 560 patients with BAV, women had significantly more AS (adjusted OR, 2.23; 95% CI, 1.19-4.20; P = 0.013) and less AI (adjusted OR 0.42; 95% CI, 0.23-0.78; P < 0.01); whereas no sex difference was found among patients with TAV.

CONCLUSIONS

In this large study of patients undergoing cardiac surgery, we found greater degree of aortic dilation in women compared to men suggesting a need for earlier monitoring of women. Moreover, women with BAV had a significantly higher prevalence of AS compared to men. These results describe the aorta and valvular characteristics of patients by sex and provide guidance regarding which patients might benefit from closer surveillance.

Epidemiology of Aortic Stenosis/Aortic Valve Replacement (from the Nationwide Swedish Renal Registry)

Contemporary data on the prevalence and incidence of aortic stenosis (AS) and aortic valve replacement (AVR) in patients initiating dialysis are scarce. This observational cohort study aimed to estimate (1) the point prevalence of AS and AVR at dialysis start and (2) the AS incidence and associated factors prospective to dialysis initiation. The study included 14,550 patients initiating dialysis registered in the Swedish Renal Registry between 2005 and 2018. AS was defined by the International Statistical Classification of Diseases, Tenth Revision codes, and AVR by the surgical procedure codes. Associations between covariates and outcomes were assessed in Cox regression models. The median age was 68 (57 to 77), 66% were males, and the point prevalence of AS and AVR was 3.4% and 1.1%, respectively. In those without known AS/AVR at dialysis initiation (n = 14,050), AS was diagnosed in 595 patients (incidence 16.3/1000 person-years, 95% confidence interval [CI] 15.1 to 17.7/1,000 person-years) during a median follow-up of 2.7 years (interquartile range 1.1 to 5.7). In adjusted Cox regression models, higher age (hazard ratio [HR] 1.03, 95% CI 1.02 to 1.04), male gender (HR 1.51, 95% CI 1.25 to 1.83), atrial fibrillation (HR 1.32, 95% CI 1.06 to 1.64), and hypertension (HR 1.65, 95% CI 1.03 to 2.65) were associated with incident AS. Peritoneal dialysis patients had a nonsignificant trend toward higher AS risk compared with hemodialysis (HR 1.18, 95% CI 0.99 to 1.40). About 20% of patients (n = 113) diagnosed with incident AS underwent AVR (incidence 3.1/1000 person-years, 95% CI 2.6 to 3.7/1,000). Only the male gender was associated with AVR (HR 2.07, 95% CI 1.30 to 3.30). In conclusion, the prevalence and incidence of AS and AVR in patients initiating dialysis are high. A fifth of newly diagnosed AS underwent AVR after dialysis onset.

Determinants of fibrotic atrial cardiomyopathy in atrial fibrillation. A multicenter observational study of the RETAC (reseau européen de traîtement d'arrhythmies cardiaques)-group

Aims

Despite advances in interventional treatment strategies, atrial fibrillation (AF) remains associated with significant morbidity and mortality. Fibrotic atrial myopathy (FAM) is a main factor for adverse outcomes of AF-ablation, but complex to diagnose using current methods. We aimed to derive a scoring system based entirely on easily available clinical parameters to predict FAM and ablation-success in everyday care.

Methods

In this multicenter, prospective study, a new risk stratification model termed AF-SCORE was derived in 220 patients undergoing high-density left-atrial(LA) voltage-mapping to quantify FAM. AF-SCORE was validated for FAM in an external mapping-validation cohort (n = 220) and for success following pulmonary vein isolation (PVI)-only (without adjunctive left- or right atrial ablations) in an external outcome-validation cohort (n = 518).

Results

FAM was rare in patients < 60 years (5.4%), but increased with ageing and affected 40.4% (59/146) of patients ≥ 60 years. Sex and AF-phenotype had additional predictive value in older patients and remained associated with FAM in multivariate models (odds ratio [OR] 6.194, p < 0.0001 for ≥ 60 years; OR 2.863, p < 0.0001 for female sex; OR 41.309, p < 0.0001 for AF-persistency). Additional clinical or diagnostic variables did not improve the model. AF-SCORE (+ 1 point for age ≥ 60 years and additional points for female sex [+ 1] and AF-persistency [+ 2]) showed good discrimination to detect FAM (c-statistic 0.792) and predicted arrhythmia-freedom following PVI (74.3%, 54.7% and 45.5% for AF-SCORE ≤ 2, 3 and 4, respectively, and hazard ratio [HR] 1.994 for AF-SCORE = 3 and HR 2.866 for AF-SCORE = 4, p < 0.001).

Conclusions

Age, sex and AF-phenotype are the main determinants for the development of FAM. A low AF-SCORE ≤ 2 is found in paroxysmal AF-patients of any age and younger patients with persistent AF irrespective of sex, and associated with favorable outcomes of PVI-only. Freedom from arrhythmia remains unsatisfactory with AF-SCORE ≥ 3 as found in older patients, particularly females, with persistent AF, and future studies investigating adjunctive atrial ablations to PVI-only should focus on these groups of patients.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01973-1.

Matters of the heart: Cellular sex differences

Nearly all cardiovascular diseases show sexual dimorphisms in prevalence, presentation, and outcomes. Until recently, most clinical trials were carried out in males, and many animal studies either failed to identify the sex of the animals or combined data obtained from males and females. Cellular sex in the heart is relatively understudied and many studies fail to report the sex of the cells used for in vitro experiments. Moreover, in the small number of studies in which sex is reported, most of those studies use male cells. The observation that cells from males and females are inherently different is becoming increasingly clear - either due to acquired differences from hormones and other factors or due to intrinsic differences in genotype (XX or XY). Because of the likely contribution of cellular sex differences in cardiac health and disease, here, we explore differences in mammalian male and female cells in the heart, including the less-studied non-myocyte cell populations. We discuss how the heart's microenvironment impacts male and female cellular phenotypes and vice versa, including how secretory profiles are dependent on cellular sex, and how hormones contribute to sexually dimorphic phenotypes and cellular functions. Intracellular mechanisms that contribute to sex differences, including gene expression and epigenetic remodeling, are also described. Recent single-cell sequencing studies have revealed unexpected sex differences in the composition of cell types in the heart which we discuss. Finally, future recommendations for considering cellular sex differences in the design of bioengineered in vitro disease models of the heart are provided.

Sex differences in left ventricular remodelling in patients with severe aortic valve stenosis

AIMS 

Women with severe aortic stenosis (AS) have better long-term outcome after transcatheter aortic valve implantation (TAVI) but worse survival after surgical aortic valve replacement compared with men. Whether this is related to sex differences in left ventricular (LV) remodelling is unknown. The aim of this study was to examine the sex differences in LV remodelling with multidetector row computed tomography (MDCT) and outcome in patients with severe AS undergoing TAVI between 2007 and 2018.

METHODS AND RESULTS 

A total of 289 patients (age 80 ± 6 years, 54% male) were included. LV volumes, mass, and function were analysed on pre-procedural MDCT scans. Women showed smaller LV volumes and mass compared with men. Patients were classified into four LV remodelling patterns: concentric hypertrophy (50%) was the most frequent pattern of LV remodelling followed by eccentric hypertrophy (33%), normal geometry (13%), and concentric remodelling (4%). Men showed more concentric remodelling compared with women (91% vs. 9%, respectively, P = 0.011). However, no differences were observed in the remaining LV remodelling patterns. During a median follow-up of 3.8 (IQR 2.2-5.1) years after TAVI, 87 (30%) patients died. Women demonstrated better outcome after TAVI compared with men (log-rank χ2 = 4.29, P = 0.038). No association was observed between the interaction of the LV remodelling patterns and sex with outcome.

CONCLUSION 

LV concentric hypertrophy and eccentric hypertrophy are similarly observed in men and women with severe AS but concentric remodelling was more common in men. Women demonstrated better outcome after TAVI when compared with men. The interaction between the LV remodelling patterns and sex was not associated with survival.

Impact of sex on the management and outcome of aortic stenosis patients

OBJECTIVE

The aim of this study was to assess the impact of sex on the management and outcome of patients according to aortic stenosis (AS) severity.

INTRODUCTION

Sex differences in the management and outcome of AS are poorly understood.

METHODS

Doppler echocardiography data of patients with at least mild-to-moderate AS [aortic valve area (AVA) ≤1.5 cm2 and peak jet velocity (VPeak) ≥2.5 m/s or mean gradient (MG) ≥25 mmHg] were prospectively collected between 2005 and 2015 and retrospectively analysed. Patients with reduced left ventricular ejection fraction (<50%), or mitral or aortic regurgitation >mild were excluded.

RESULTS

Among 3632 patients, 42% were women. The mean indexed AVA (0.48 ± 0.17 cm2/m2), VPeak (3.74 ± 0.88 m/s), and MG (35.1 ± 18.2 mmHg) did not differ between sexes (all P ≥ 0.18). Women were older (72.9 ± 13.0 vs. 70.1 ± 11.8 years) and had more hypertension (75% vs. 70%; P = 0.0005) and less coronary artery disease (38% vs. 55%, P < 0.0001) compared to men. After inverse-propensity weighting (IPW), female sex was associated with higher mortality (IPW-HR: 1.91 [1.14-3.22]; P = 0.01) and less referral to valve intervention (competitive model IPW-HR: 0.88 [0.82-0.96]; P = 0.007) in the whole cohort. This excess mortality in women was blunted in concordant non-severe AS initially treated conservatively (IPW-HR = 1.03 [0.63-1.68]; P = 0.88) or in concordant severe AS initially treated by valve intervention (IPW-HR = 1.25 [0.71-2.21]; P = 0.43). Interestingly, the excess mortality in women was observed in discordant low-gradient AS patients (IPW-HR = 2.17 [1.19-3.95]; P = 0.01) where women were less referred to valve intervention (IPW-Sub-HR: 0.83 [0.73-0.95]; P = 0.009).

CONCLUSION

In this large series of patients, despite similar baseline hemodynamic AS severity, women were less referred to AVR and had higher mortality. This seemed mostly to occur in the patient subset with discordant markers of AS severity (i.e. low-gradient AS) where women were less referred to AVR.

Sex differences in transaortic flow rate and association with all-cause mortality in patients with severe aortic stenosis

AIMS

It is not known whether transaortic flow rate (FR) in aortic stenosis (AS) differs between men and women, and whether the commonly used cut-off of 200 mL/s is prognostic in females. We aimed to explore sex differences in the determinants of FR, and determine the best sex-specific cut-offs for prediction of all-cause mortality.

METHODS AND RESULTS

Between 2010 and 2017, a total of 1564 symptomatic patients (mean age 76 ± 13 years, 51% men) with severe AS were prospectively included. Mean follow-up was 35 ± 22 months. The prevalence of cardiovascular disease was significantly higher in men than women (63% vs. 42%, P < 0.001). Men had higher left ventricular mass and lower left ventricular ejection fraction compared to women (both P < 0.001). Men were more likely to undergo an aortic valve intervention (AVI) (54% vs. 45%, P = 0.001), while the death rates were similar (42.0% in men and 40.6% in women, P = 0.580). A total of 779 (49.8%) patients underwent an AVI in which 145 (18.6%) died. In a multivariate Cox regression analysis, each 10 mL/s decrease in FR was associated with a 7% increase in hazard ratio (HR) for all-cause mortality (HR 1.07; 95% CI 1.03-1.11, P < 0.001). The best cut-off value of FR for prediction of all-cause mortality was 179 mL/s in women and 209 mL/s in men.

CONCLUSION

Transaortic FR was lower in women than men. In the group undergoing AVI, lower FR was associated with increased risk of all-cause mortality, and the optimal cut-off for prediction of all-cause mortality was lower in women than men.

Sex and Race Differences in the Pathophysiology, Diagnosis, Treatment, and Outcomes of Valvular Heart Diseases

Valvular heart diseases have long been considered to be similar in men and women and across races/ethnicities. Recently, studies have demonstrated major differences between sexes. Unfortunately, studies on valvular heart diseases, as on other cardiovascular diseases, are mostly performed in Caucasian men or in cohorts with a vast majority of Caucasian men. Therefore, our knowledge on valvular diseases in women and non-Caucasians remains limited. Nevertheless, aortic stenosis has been shown to be almost as prevalent in women as in men, and less prevalent in African Americans. Men appear to have a more calcified aortic valve lesion, and women tend to have a more fibrosed one. Primary mitral regurgitation is more frequent in women who have more rheumatic and Barlow etiologies, whereas men have more fibroelastic deficiency and posterior leaflet prolapse/flail. Left ventricular remodelling due to valvular heart diseases is sex related in terms of geometry and probably also in composition of the tissue. Outcomes seem to be worse in women after surgical interventions and better than or equivalent to men after transcatheter ones. Regarding other valvular heart diseases, very few studies are available: Aortic regurgitation is more frequent in men, isolated tricuspid regurgitation more frequent in women. Rheumatic valve diseases are more frequent in women and are mostly represented by mitral and aortic stenoses. Many other sex/gender- and race/ethnic-specific studies are still needed in epidemiology, pathophysiology, presentation, management, and outcomes. This review aims to report the available data on sex differences and race specificities in valvular heart diseases, with a primary focus on aortic stenosis and mitral regurgitation.

Cardiac fibrosis

Myocardial fibrosis, the expansion of the cardiac interstitium through deposition of extracellular matrix proteins, is a common pathophysiologic companion of many different myocardial conditions. Fibrosis may reflect activation of reparative or maladaptive processes. Activated fibroblasts and myofibroblasts are the central cellular effectors in cardiac fibrosis, serving as the main source of matrix proteins. Immune cells, vascular cells and cardiomyocytes may also acquire a fibrogenic phenotype under conditions of stress, activating fibroblast populations. Fibrogenic growth factors (such as transforming growth factor-β and platelet-derived growth factors), cytokines [including tumour necrosis factor-α, interleukin (IL)-1, IL-6, IL-10, and IL-4], and neurohumoral pathways trigger fibrogenic signalling cascades through binding to surface receptors, and activation of downstream signalling cascades. In addition, matricellular macromolecules are deposited in the remodelling myocardium and regulate matrix assembly, while modulating signal transduction cascades and protease or growth factor activity. Cardiac fibroblasts can also sense mechanical stress through mechanosensitive receptors, ion channels and integrins, activating intracellular fibrogenic cascades that contribute to fibrosis in response to pressure overload. Although subpopulations of fibroblast-like cells may exert important protective actions in both reparative and interstitial/perivascular fibrosis, ultimately fibrotic changes perturb systolic and diastolic function, and may play an important role in the pathogenesis of arrhythmias. This review article discusses the molecular mechanisms involved in the pathogenesis of cardiac fibrosis in various myocardial diseases, including myocardial infarction, heart failure with reduced or preserved ejection fraction, genetic cardiomyopathies, and diabetic heart disease. Development of fibrosis-targeting therapies for patients with myocardial diseases will require not only understanding of the functional pluralism of cardiac fibroblasts and dissection of the molecular basis for fibrotic remodelling, but also appreciation of the pathophysiologic heterogeneity of fibrosis-associated myocardial disease.

Sex-Specific Associations of Cardiovascular Risk Factors and Biomarkers With Incident Heart Failure

BACKGROUND

Whether cardiovascular (CV) disease risk factors and biomarkers associate differentially with heart failure (HF) risk in men and women is unclear.

OBJECTIVES

The purpose of this study was to evaluate sex-specific associations of CV risk factors and biomarkers with incident HF.

METHODS

The analysis was performed using data from 4 community-based cohorts with 12.5 years of follow-up. Participants (recruited between 1989 and 2002) were free of HF at baseline. Biomarker measurements included natriuretic peptides, cardiac troponins, plasminogen activator inhibitor-1, D-dimer, fibrinogen, C-reactive protein, sST2, galectin-3, cystatin-C, and urinary albumin-to-creatinine ratio.

RESULTS

Among 22,756 participants (mean age 60 ± 13 years, 53% women), HF occurred in 2,095 participants (47% women). Age, smoking, type 2 diabetes mellitus, hypertension, body mass index, atrial fibrillation, myocardial infarction, left ventricular hypertrophy, and left bundle branch block were strongly associated with HF in both sexes (p < 0.001), and the combined clinical model had good discrimination in men (C-statistic = 0.80) and in women (C-statistic = 0.83). The majority of biomarkers were strongly and similarly associated with HF in both sexes. The clinical model improved modestly after adding natriuretic peptides in men (ΔC-statistic = 0.006; likelihood ratio chi-square = 146; p < 0.001), and after adding cardiac troponins in women (ΔC-statistic = 0.003; likelihood ratio chi-square = 73; p < 0.001).

CONCLUSIONS

CV risk factors are strongly and similarly associated with incident HF in both sexes, highlighting the similar importance of risk factor control in reducing HF risk in the community. There are subtle sex-related differences in the predictive value of individual biomarkers, but the overall improvement in HF risk estimation when included in a clinical HF risk prediction model is limited in both sexes.

Extracellular Myocardial Volume in Patients With Aortic Stenosis

Background

Myocardial fibrosis is a key mechanism of left ventricular decompensation in aortic stenosis and can be quantified using cardiovascular magnetic resonance (CMR) measures such as extracellular volume fraction (ECV%). Outcomes following aortic valve intervention may be linked to the presence and extent of myocardial fibrosis.

Objectives

This study sought to determine associations between ECV% and markers of left ventricular decompensation and post-intervention clinical outcomes.

Methods

Patients with severe aortic stenosis underwent CMR, including ECV% quantification using modified Look-Locker inversion recovery–based T1 mapping and late gadolinium enhancement before aortic valve intervention. A central core laboratory quantified CMR parameters.

Results

Four-hundred forty patients (age 70 ± 10 years, 59% male) from 10 international centers underwent CMR a median of 15 days (IQR: 4 to 58 days) before aortic valve intervention. ECV% did not vary by scanner manufacturer, magnetic field strength, or T1 mapping sequence (all p > 0.20). ECV% correlated with markers of left ventricular decompensation including left ventricular mass, left atrial volume, New York Heart Association functional class III/IV, late gadolinium enhancement, and lower left ventricular ejection fraction (p < 0.05 for all), the latter 2 associations being independent of all other clinical variables (p = 0.035 and p < 0.001). After a median of 3.8 years (IQR: 2.8 to 4.6 years) of follow-up, 52 patients had died, 14 from adjudicated cardiovascular causes. A progressive increase in all-cause mortality was seen across tertiles of ECV% (17.3, 31.6, and 52.7 deaths per 1,000 patient-years; log-rank test; p = 0.009). Not only was ECV% associated with cardiovascular mortality (p = 0.003), but it was also independently associated with all-cause mortality following adjustment for age, sex, ejection fraction, and late gadolinium enhancement (hazard ratio per percent increase in ECV%: 1.10; 95% confidence interval [1.02 to 1.19]; p = 0.013).

Conclusions

In patients with severe aortic stenosis scheduled for aortic valve intervention, an increased ECV% is a measure of left ventricular decompensation and a powerful independent predictor of mortality.

How low is "low-flow" in aortic stenosis? A retrospective analysis of patients with true low-flow/low-gradient aortic stenosis undergoing TAVI

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is a valuable treatment option for patients with reduced left ventricular ejection fraction (LVEF) and low-flow/low-gradient (LF/LG) aortic stenosis (AS). According to current literature, the presence of severe AS is unlikely in case of severely reduced LVEF and mean pressure gradient (meanPG) below 30 mmHg. However, a considerable number of patients presenting with typical clinical symptoms of severe AS, show gradients below 30 mmHg. We hypothesized, that these patients undergoing TAVI do have a measurable clinical benefit and an improved LVEF.

METHODS

In this single center retrospective cohort study, data from 1199 patients undergoing TAVI between 2013 and 2017 was analyzed. A 6-month follow-up was performed to assess changes in NT-proBNP, NYHA-class, and LVEF.

RESULTS

Thirty patients presented with LVEF<35%, an aortic valve area (AVA<1 cm²), and a meanPG below 30 mmHg. Mean logistic EuroSCORE II was 24.05±10.9. Most patients (56%) showed improved NYHA-class upon follow-up. NT-proBNP-levels decreased from 3.901 pg/mL IQR 10.880 to 1.491 pg/mL IQR 2.245 (P<0.001). LVEF increased from 30% IQR 6.25 to 40% IQR 15 (P<0.001).

CONCLUSIONS

Based on our findings TAVI represents a valuable treatment option even in patients with LF/LG AS and PGmean below 30mmHg.