Conclusions
In this study, we looked to identify the impact of sex on remodeling and outcomes post MVR. After propensity matching and isolating for surgical approach, our results demonstrate significant cardiac remodeling postoperatively for both sexes. Interestingly the cardiac remodeling was inconsistent between the two groups. Males showed significantly improved remodeling of the LV while females had significant remodeling of the LA. A study by Goldstein et al randomized 251 patients to either MV repair or replacement and followed the patients for 2 years. Both MV repair and replacement groups demonstrated significant remodeling of the LV end-systolic volume index within the first year postoperatively [22]. Ebd Alaziz & Ibrahim similarly followed 20 males and 25 females who had undergone MVR for chronic MR. These patients demonstrated a reduction in LVEF from 61.09±7.6% to 59.67±6.56%, in LA size from 5.55±0.88cm to 4±0.54cm, and LV end-systolic diameter from 4.06±0.65cm to 3.45±0.51cm at 1-year postoperatively [23]. Even so, no studies have compared the differences in remodeling between sexes with a large number of propensity-matched patients and our results demonstrate a difference in the heart’s ability to remodel after MVR. Males demonstrated a significant reduction in LV size and LVEF, while females did not. Females demonstrated a significant reduction in LA size and volume, while males did not. This distinction in cardiac remodeling demonstrates variability in cardiac adaptation after MV surgery. The significance of this difference has the potential to result in variable clinical outcomes for males and females, including long-term freedom from heart failure and mortality. Further study is necessary to fully elucidate this relationship.
In contrast to previous literature, our results demonstrated that after propensity matching and isolating for surgical approach females and males have similar rates of morbidity and mortality post MVR, and when there were significant differences between the sexes males had inferior outcomes. Vassileva et al performed a study including 47,602 patients undergoing isolated MV surgery and divided patients by sex and surgical approach [12]. This study found the MV repair rate for males was 44.0% and 31.9% for females, with remaining patients receiving MVR. Higher operative and in-hospital mortality rates were identified for females. Women demonstrated a higher mortality rate than men with 8.2% and 9.3% for males and females respectively. Even after adjustment for differences in baseline characteristics and admission status, the mortality rate for females undergoing MVR was still increased compared to their male counterparts [12]. Song et al demonstrated similar results with their study of 24,977 patients from The STS National Database who underwent isolated MV repair or replacement [18]. Females were shown to have significantly increased rates of morbidity and mortality with the largest difference being in the 40-59 year age group with approximately 2.5x the rates of mortality in females as compared to males, this survival disadvantage diminished with aging [18]. As there were multiple potential causes of these discrepancies in prior literature, we sought to identify whether sex alone impacts the outcomes post-MV surgery by matching patients based on comorbidities and isolating for surgical approach. We found no significant difference in mortality between males and females following MVR. Our results demonstrated that when males and females were matched for preoperative comorbidities and surgical approaches, males had inferior postoperative with an increased likelihood of developing sepsis and requiring rehospitalization due to MI postoperatively than females.
Our results have demonstrated significant variations in cardiac remodeling between males and females post MVR. Both males and females demonstrated significant changes in MVA as well as peak and mean gradients, although chamber remodeling was distinctly different between the sexes. Males demonstrated a significant reduction in LV diameter and LVEF while females did not show these changes. In contrast, females showed a significant reduction in LA diameter and volume while males did not. This difference in chamber remodeling demonstrates variability in the heart’s ability to adapt after MV surgery. The significance of this difference is unknown but has the potential to result in different clinical outcomes between the sexes, including long-term freedom from symptoms of heart failure and rates of mortality. Further study of this discrepancy is necessary to fully elucidate this relationship.