Clinical outcomes after trans-catheter aortic valve replacement in men and women in Ontario, Canada

Sex Differences in Aortic Stenosis: From the Pathophysiology to the Intervention, Current Challenges, and Future Perspectives

Calcific aortic stenosis (AS) is a major cause of morbidity and mortality in high-income countries. AS presents sex-specific features impacting pathophysiology, outcomes, and management strategies. In women, AS often manifests with a high valvular fibrotic burden, small valvular annuli, concentric left ventricular (LV) remodeling/hypertrophy, and, frequently, supernormal LV ejection fraction coupled with diastolic dysfunction. Paradoxical low-flow low-gradient AS epitomizes these traits, posing significant challenges post-aortic valve replacement due to limited positive remodeling and significant risk of patient-prosthesis mismatch. Conversely, men present more commonly with LV dilatation and dysfunction, indicating the phenotype of classical low-flow low-gradient AS, i.e., with decreased LV ejection fraction. However, these distinctions have not been fully incorporated into guidelines for AS management. The only treatment for AS is aortic valve replacement; women are frequently referred late, leading to increased heart damage caused by AS. Therefore, it is important to reassess surgical planning and timing to minimize irreversible cardiac damage in women. The integrity and the consideration of sex differences in the management of AS is critical. Further research, including sufficient representation of women, is needed to investigate these differences and to develop individualized, sex-specific management strategies.

Sex-Specific Considerations in Degenerative Aortic Stenosis for Female-Tailored Transfemoral Aortic Valve Implantation Management

The impact of sex on pathophysiological processes, clinical presentation, treatment options, as well as outcomes of degenerative aortic stenosis remain poorly understood. Female patients are well represented in transfemoral aortic valve implantation (TAVI) trials and appear to derive favorable outcomes with TAVI. However, higher incidences of major bleeding, vascular complications, and stroke have been reported in women following TAVI. The anatomical characteristics and pathophysiological features of aortic stenosis in women might guide a tailored planning of the percutaneous approach. We highlight whether a sex-based TAVI management strategy might impact on clinical outcomes. This review aimed to evaluate the impact of sex from diagnosis to treatment of degenerative aortic stenosis, discussing the latest evidence on epidemiology, pathophysiology, clinical presentation, therapeutic options, and outcomes. Furthermore, we focused on technical sex-oriented considerations in TAVI including the preprocedural screening, device selection, implantation strategy, and postprocedural management.

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.

Aortic stenosis in women

Aortic stenosis (AS) is a common valve disorder in an ageing population in western countries, and women, with longer life expectancy, comprise a substantial percentage of elderly patients with AS. Compared with men, women exhibit distinctive characteristics at the level of stenotic valve leaflets and subsequent compensatory responses of the left ventricle to chronic pressure overload, and in clinical presentation, consequences and response to intervention. Randomised controlled trials of transcatheter aortic valve implantation have yielded new evidence of sex differences in both short-term and long-term outcomes after intervention. A comprehensive knowledge of the existing evidence may inform our understanding of gender differences during assessment and treatment of patients with AS. In this paper, we review the available evidence regarding sex differences in AS in terms of symptoms, clinical presentation, anatomical differences and pathophysiological progression, management and outcomes after aortic valve replacement. Implications for further research are suggested.

Longitudinal Outcomes of Women Undergoing Transcatheter Aortic Valve Replacement

OBJECTIVE

Recent data have suggested that women have a survival benefit at 1-year follow-up. However, long-term gender-based TAVR outcomes are lacking.

METHODS

All patients undergoing isolated TAVR from 2011 to 2017 were included. Patients were stratified by gender. The primary outcomes of the study were 3-year mortality and 3-year hospital readmissions. Multivariable logistic regression analysis was used to evaluate the risk-adjusted impact of gender on TAVR outcomes.

RESULTS

A total of 1,036 patients were divided into male (n = 518) and female (n = 518) cohorts. Women had a borderline significantly increased STS PROM (8.3% ± 5 vs. 7.7% ± 4.4; P = 0.05). The majority of procedures were performed under conscious sedation (male: 89% vs. female: 88%; P = 0.62) and via transfemoral access (male: 81.8% vs. female: 81.4%; P = 0.46). There was no difference in operative (30-day) mortality (male: 15 [3.3%] vs. female: 17 [3.7%]; P = 0.77) or 30-day readmissions (male: 40 [10.8%] vs. female: 44 [12.2%]; P = 0.56). Perioperative blood product usage was higher for women (male: 8.1% vs. female: 14.1%; P = 0.002). There was no significant difference in major vascular complications (male: 0.4% vs. female: 1.0%; P = 0.26) or major bleeding (male: 0.2% vs. female: 0.4%; P = 0.56). Permanent pacemaker placement was higher for males (11.6% vs. 7.0%; P = 0.01). On risk-adjusted multivariable analysis, gender was not a factor associated with mortality (HR 0.99 [0.76 to 1.30]; P = 0.99) or readmission (HR 0.90 [0.72 to 1.14]; P = 0.42) at 5 years.

CONCLUSIONS

There was no difference in survival or readmissions on multivariable analysis for women undergoing TAVR at 3 years. Longitudinal multi-institutional data will be important to validate these findings.

Gender Disparities in Management and Outcomes Following Transcatheter Aortic Valve Implantation With Newer Generation Transcatheter Valves

The impact of gender on management and early outcomes after transcatheter aortic valve implantation (TAVI) in the setting of newer generation transcatheter heart valves (THVs) is not well known. We evaluated gender-specific differences on clinical management and in-hospital outcomes in adults who underwent TAVI with newer generation THVs. The study population included 298 consecutive patients who underwent TAVI and received a newer generation THV (Sapien 3 [Edwards Lifesciences, Irvine, California] or Corevalve Evolut R or Evolut Pro [Medtronic, Minneapolis, Minnesota]) from December 2015 to June 2018 at an academic tertiary medical center. Of the 298 patients, 154 (52%) were men and 144 (48%) were women. Compared with men, women were older, had lower serum creatinine, higher left ventricular ejection fraction, and lower rates of multiple co-morbidities, including previous coronary artery bypass graft surgery, previous myocardial infarction, and atrial fibrillation. Women were noted to have smaller aortic annular area and perimeter and underwent implantation of smaller THVs than men. At the time of discharge, women were more frequently prescribed a P2Y12 inhibitor (primarily clopidogrel) and less frequently prescribed oral anticoagulation (namely warfarin). Hospital length of stay and in-hospital rates of mortality, disabling stroke, and pacemaker were similar in men and women. In conclusion, in this observational prospective study of adults who underwent TAVI with newer generation THVs, while gender-related disparities in clinical presentation and procedural management were observed, no significant difference in clinical outcomes were noted in men and women. Further studies examining gender-related differences in procedural and postprocedural care after TAVI in the contemporary era are warranted to better understand and optimize clinical outcomes in both men and women.

Association between transitional care factors and hospital readmission after transcatheter aortic valve replacement: a retrospective observational cohort study

Background

Studies have shown that patients who undergo trans-catheter aortic valve replacement (TAVR) have high rates of hospital readmission. Our objectives were to identify the causes of readmission after TAVR, determine whether transitional care factors were associated with a reduction in readmission and to identify other predictors that could be used to target quality improvement efforts.

Methods

We conducted a chart abstraction study that included all patients who underwent TAVR in Ontario, Canada between 2007 and 2013 and survived to hospital discharge. These data were linked to provincial administrative databases. The association between transitional care factors (home care, rehabilitation, family physician and cardiologist follow-up) and 1-year hospital readmission was examined using a time-to-event analysis. Cause-specific hazards models were used to account for the competing risk of death.

Results

There were 937 patients in the cohort and the rate of readmission at 1-year was 49%. The most common causes of readmission were heart failure and bleeding. Rehabilitation (HR 1.34, 95% CI 1.11–1.62; p = 0.002) and cardiologist follow-up (HR 1.41, 95% CI 1.14–1.75; p = 0.002) were both associated with higher readmission rates. While, home care (HR 1.18, 95% CI 0.96–1.44; p = 0.12) and family physician follow-up (HR 1.04, 95% CI 0.85–1.28; p = 0.71) were not associated with readmission.

Conclusion

Readmission post TAVR is common; however, we did not identify any transitional care factors associated with reductions in hospital readmission. This suggests ongoing research is required to identify targets for improvement in post-procedural care.

Sex-Specific Considerations in Women with Aortic Stenosis and Outcomes After Transcatheter Aortic Valve Replacement

Aortic stenosis (AS) is the most common valvular disease in the elderly and is associated with poor outcomes. Transcatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement (SAVR) in high-risk patients. Herein, we describe the gender-related differences in baseline characteristics and pathophysiologic response to severe AS, imaging considerations unique to females, and short- and long-term outcomes after TAVR. Women undergoing TAVR are older and frailer, have less cardiovascular comorbidities, smaller femoral artery size, better left ventricular systolic function, hypertrophied and small left ventricles leading to a higher incidence of paradoxical low-flow low-gradient AS, and a greater prevalence of porcelain aorta, smaller aortic annulus size, and lower coronary ostia heights. Imaging and histopathological data also suggests a sex-related myocardial response to pressure overload from AS. Women experience more vascular complications and blood transfusion requirements, serious procedural complications, and a greater incidence of stroke, but have better long-term outcomes than men. Patient-prosthesis mismatch, which is a concern in patients with a small aortic annulus size undergoing SAVR, has not been problematic with TAVR. The aforementioned findings suggest that TAVR may be preferable for women with severe AS. Further studies are warranted to directly compare TAVR with SAVR in women.

Comparison of Baseline Characteristics and Outcomes in Men Versus Women With Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

Female gender has been linked to increased risk of adverse events after surgical aortic valve replacement; however, the evidence regarding the role of gender differences on clinical outcomes in patients who underwent transcatheter aortic valve implantation (TAVI) is still debated. This retrospective study included 910 consecutive patients with severe, symptomatic aortic stenosis who underwent TAVI in 2 institutions from January 2012 to July 2016. The primary end point was all-cause mortality at 1 year after TAVI in women versus men. Women had a higher incidence of in-hospital vascular complications (7.8% vs 4.1%) and major or life-threatening bleeding (4.0% vs 1.6%) than men. At 1 year, women showed a lower mortality rate than men (7.0% vs 12.7%, adjusted hazard ratio [HR] 0.42, 95% confidence interval [CI] [0.23 to 0.76], p = 0.004). When stratifying by specific subgroups of interest, the survival benefit in women persisted in (1) patients with a Society of Thoracic Surgery risk score ≤ 8 (adjusted HR 0.35, 95% CI [0.14 to 0.88], p = 0.026); (2) patients treated with first-generation devices (adjusted HR 0.46, 95% CI [0.24 to 0.86], p = 0.016); and (3) patients treated with balloon-expandable valves (adjusted HR 0.40, 95% CI [0.19 to 0.86], p = 0.019). In conclusion, in this large patient cohort, women had lower 1-year mortality after TAVI than men, particularly with an STS score ≤ 8, or treated with first-generation and balloon-expandable devices.