This contemporary multicenter retrospective cohort study by Kubi et al. examines sex-based differences in outcomes following mitral valve (MV) surgery, analyzing data from 3,313 adult patients treated between 2011 and 2024 at two major academic institutions. The research addresses a longstanding clinical question: whether biological sex independently influences operative mortality and postoperative outcomes after mitral valve surgery, or whether observed disparities are driven by differences in presentation, treatment selection, and comorbid conditions.
Women comprised 44.5% of the study population and demonstrated notable differences in baseline characteristics compared to men. They were slightly older at the time of surgery and more likely to present with advanced heart failure symptoms, particularly New York Heart Association (NYHA) class III and IV disease. Additionally, women had higher rates of chronic lung disease and prior stroke. These findings reinforce prior evidence suggesting delayed referral and more advanced disease at the time of surgical intervention in female patients.
One of the most striking differences identified in the study was procedural selection. Women were significantly less likely to undergo mitral valve repair (63.5% vs. 80.0% in men), instead more frequently receiving valve replacement. This disparity may be influenced by anatomical and pathological differences, such as smaller annular dimensions or increased calcification, but may also reflect systemic biases or delayed diagnosis. The study also noted lower utilization of robotic surgical approaches in women, further emphasizing potential differences in treatment strategies.
Despite these variations in baseline characteristics and operative management, the primary outcome—operative mortality—did not significantly differ between sexes. Mortality rates were low overall (1.42% in women vs. 0.92% in men), and multivariable logistic regression confirmed that female sex was not an independent predictor of mortality (OR 1.03, P=0.66). Instead, prolonged cardiopulmonary bypass time emerged as a significant predictor of mortality, underscoring the importance of intraoperative factors over patient sex alone.
Postoperative outcomes revealed a more nuanced picture. While major complications such as stroke, renal failure, infection, and prolonged ventilation were similar between sexes, women experienced significantly longer ICU stays (3.0 vs. 2.3 days) and longer overall hospitalizations (8.4 vs. 7.1 days). Interestingly, women had lower rates of reoperation for bleeding but higher adjusted odds of 30-day readmission, suggesting that longer hospital stays do not necessarily mitigate post-discharge risks.
The findings highlight that while survival outcomes are comparable, recovery trajectories differ meaningfully between men and women. These differences may be attributable to a combination of biological factors, comorbidities, and healthcare system dynamics, including postoperative care pathways and discharge planning.
The study’s strengths include its large sample size, contemporary data spanning over a decade, and robust multivariable analysis. The inclusion of both repair and replacement procedures enhances its generalizability compared to prior studies focused on narrower patient populations. However, limitations include its retrospective design and restriction to two high-volume academic centers, which may limit broader applicability. Additionally, the absence of detailed echocardiographic data prevents deeper analysis of anatomical factors influencing procedural decisions.
Clinically, the study suggests that sex alone should not be considered a risk factor for operative mortality in mitral valve surgery. Instead, disparities in outcomes appear to stem from differences in disease severity at presentation and procedural selection. These findings underscore the importance of earlier referral, equitable access to advanced surgical techniques, and individualized perioperative care strategies.
From a healthcare systems perspective, the research calls for targeted interventions to address sex-based disparities in cardiovascular care. Improving awareness, refining guideline thresholds to account for sex-specific anatomical differences, and optimizing recovery protocols may help bridge these gaps. Ultimately, the study reinforces that improving equity in care delivery—not biological sex—is key to enhancing outcomes for patients undergoing mitral valve surgery.
