CT-Derived Skeletal Muscle Index Predicts Post TAVR Length of Stay and 1 Year QOL

Background:
The impact of skeletal muscle mass on post TAVR quality of life (QOL) is unclear. We compared the baseline clinical characteristics of sarcopenic and non-sarcopenic patients undergoing TAVR and determined the relationship between skeletal muscle index (SMI), post TAVR length of hospital stay (LOS) and 1 year QOL.

Methods:
The study sample consisted of 344 consecutive patients undergoing TAVR at a single center from 2012- 2018 who had pre-TAVR CT scans suitable for body composition analysis. SMI was derived from a single CT cross-sectional image at the third lumbar vertebra. Sarcopenia was defined using established sex-specific cut-offs (SMI< 39 cm²/m²for women and < 55 cm²/m² for men). Baseline clinical characteristics and 1 year QOL (KCCQ summary score) were extracted from the STS/ACC TVT Registry. Multivariable regression analysis was used to determine the relationship between SMI, LOS and QOL.

Results:
Sarcopenia was prevalent (59%) and associated with older age (82 vs 76 years; p<0.001) and lower BMI (27 vs. 33 kg/m2; p<0.001). There were no other differences in baseline clinical or echocardiographic characteristics. SMI was positively correlated with 1 year QOL (Fig. 1). After adjusting for age, gender and race, SMI remained a significant predictor of LOS (p=0.012) and 1 year QOL (p=0.012). For every 10 cm²/m²increase in SMI, there was a clinically meaningful 7.1 point increase in KCCQ score.

Conclusions:
Sarcopenia remains prevalent in TAVR patients. SMI predicts post TAVR LOS and 1 year QOL. To achieve optimal TAVR benefits, further study into how body composition influences post TAVR recovery and long-term improvement is warranted.