Clinical Frailty as an Outcome Predictor After Transcatheter Aortic Valve Implantation

Society of Thoracic Surgeons (STS) score and frailty index are calculated routinely as part of transcatheter aortic valve implantation (TAVI) assessment to determine procedure risk. We aim to evaluate the incremental improvement of STS risk score using frailty status in predicting short- and long-term outcome after TAVI. Study population included 544 consecutive TAVI patients who completed full frailty assessment and STS score calculation before the procedure. Frailty is defined by the presence of any 3 of the following 5 criteria: algorithm-defined grip strength and 15-foot walking tests, body mass index < 20 kg/m², Katz activity of daily living ≤ 4/6, serum albumin < 3.5 g/dl. Multivariable logistic analysis of 30-day and 1-year mortality was performed using a logistic regression model that comprised the STS risk score model as a single variable. Based on frailty definition, 242 patients were frail and 302 patients were not. STS score was higher in the frail group than in the nonfrail group. Compared with STS risk score alone, frailty status was a significant predictor of 1-year mortality after TAVI procedure (odds ratio 1.0, 95% confidence interval [CI] 1.0 to 1.1, p = 0.029 vs 2.75, 95% CI 1.55 to 4.87, p <0.001, respectively). Although the c-statistic of the 1-year STS risk prediction model only changed from 0.62 to 0.66 (p = 0.08), the net reclassification improvement increased significantly to 52.8% after adding frailty to the prediction model (95% CI 0.28 to 0.77, p <0.0001). Frailty status is associated with higher mortality in TAVI cohort and incrementally improves the well-validated STS risk prediction model. Frailty assessment should continue to be part of the preprocedural assessment to further improve patient outcomes after TAVI.