Introduction
In the context of Transcatheter Aortic Valve Implantation(TAVI), females often present with higher Society of Thoracic Surgeons(STS) mortality score values. Paradoxically, however, they tend to exhibit greater survival post-TAVI compared to males. Previous literature has shown that body composition(BC) may affect prognosis in cardiometabolic diseases. Specifically, increased visceral adipose tissue(VAT) and decreased skeletal muscle(SM) have been associated with worse outcomes, whereas subcutaneous adipose tissue(SAT) has shown a protective role. Nevertheless, whether these factors specifically interact with outcomes in relation to gender in patients treated with TAVI is still unknow.
Methods
Data of patients who underwent TAVI in 2010-2022 were collected. The areas of SM, VAT and SAT were measured from scans at the third lumbar vertebra of preoperative CT exams. Variables are expressed as median[25p-75p] or absolute number(%) and were compared by Mann-Whitney and Chi-square test as appropriate. Mortality analyses were performed through Kaplan-Meier curves with log rank test and Cox regression models.
Results
We enrolled 168 consecutive patients, including 89(53.3%) females. The median age was 84[81-86] years. In comparison to males, females exhibited higher values of STS mortality score (4.2[3.1-6.3] vs. 3.5[2.4-5.4], p=0.021) and SAT (189[111-242] vs. 135[92-170] cm2, p=0.001), along with lower values of SM (92[81-106] vs. 129[115-144] cm2, 0.0001) and VAT (116[48-197] vs. 210[118-266] cm2, 0.0001). Additional differences are detailed in Table 1. The overall 1-year mortality was 15.6%, with females exhibiting lower mortality rates compared to males (10.1% vs. 21.8%, OR=4.5, p=0.033), as illustrated in Figure 1. In the multivariate analysis, female sex emerged as an independent predictor of better survival after adjusting for the STS mortality score (HR=0.4, 95% CI 0.2-0.9, p=0.028).
Conclusions
In our cohort, female patients experienced lower 1-year mortality after TAVI compared to males. As females showed less SM and VAT and more SAT, we hypothesize that the interplay between muscle and adipose tissue, along with hormonal, inflammatory, and metabolic mechanisms, may create a more favorable cardiovascular environment, counteracting the higher pre-procedural STS mortality score. A distinct pattern of BC appears to be protective in female patients undergoing TAVI, and its evaluation could help optimize gender-specific risk stratification.
