Usefulness of Psoas Muscle Area to Predict Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement

Abstract Frailty has become high-priority theme in cardiovascular diseases due to aging and increasingly complex nature of patients. Low muscle mass is characteristic of frailty, in which invasive interventions are avoided if possible due to decreased physiological reserve. This study aimed to determine if the psoas muscle area (PMA) could predict mortality, and to investigate it utility in patients undergoing transcatheter aortic valve replacement (TAVR). We retrospectively reviewed 232 consecutive patients undergoing TAVR. Cross-sectional areas of the psoas muscles at the L4 level were measured by computed tomography and normalized to body surface area. Patients were divided into tertiles according to the normalized PMA for each gender (men: Tertile 1, 1708–1178 mm2 /m2 ; Tertile 2, 1176–1011 mm2 /m2 ; and Tertile 3, 1009–587 mm2 /m2 ; women: Tertile 1, 1436–962 mm2 /m2 ; Tertile 2, 952–807 mm2 /m2 ; and Tertile 3, 806–527 mm2 /m2 ). Smaller normalized PMA was independently correlated with women and higher New York Heart Association classification. After adjustment for multiple confounding factors, the normalized PMA tertile was independently associated with mortality at 6 months (adjusted hazard ratio, 1.53 [95% confidence interval, 1.06–2.21]). Kaplan-Meier analysis showed that Tertile 3 had higher mortality rates than Tertile 1 at 6 months (14% and 31%, respectively, p=0.029). Receiver-operating characteristic analysis showed that normalized PMA provided the increase of C -statistics for predicting mortality for a clinical model, and gait speed. In conclusion, PMA is an independent predictor of mortality after TAVR and can complement a clinical model and gait speed.