Sarcopenia index as a predictor of clinical outcomes in older patients undergoing transcatheter aortic valve replacement.

BACKGROUND Sarcopenia is a prevalent condition in elderly patients and has been associated with adverse outcomes following transcatheter aortic valve replacement (TAVR). The present study aimed to determine the predictive value of serum creatinine-cystatin C ratio, that is, "Sarcopenia Index" (SI) as a surrogate marker of sarcopenia, and investigate its association with clinical outcomes after TAVR. METHODS We conducted a retrospective observational study of patients undergoing TAVR between January, 2016 and December, 2018 at Hospital Italiano de Buenos Aires, Argentina. Patients were excluded if <65-years old, presented previous surgical aortic valve replacement, severe chronic kidney disease, or hemodialysis requirement. The SI was obtained at baseline before TAVR. All-cause mortality and/or readmissions for congestive heart failure (CHF) were defined as the primary endpoint. RESULTS In total 100 patients met inclusion criteria for the purpose of the study. Sarcopenia Index was significantly correlated with Timed Up and Go (r = -0.272, p = .010) and Gait Speed (r = -0.278, p = .005). During follow-up, 5/100 patients died within 30 days and a total of 10/100 patients died at 1-year follow-up. Moreover, survival curves were significantly worse (Log-rank test = p = .02) and CHF readmissions were more prevalent in the lowest SI tertile (Log-rank test = p = .01). In multivariate Cox regression analysis, we identified low SI (cutoff ≤66) as an independent predictor of long-term adverse outcomes (HR = 4.01, 95% CI = 1.31-12.27, p = .015) at 1-year follow-up. CONCLUSION Sarcopenia Index, surrogate for the degree of skeletal muscle mass (SMM), could be used as a predictor of adverse outcomes in patients undergoing TAVR.