Background: Several studies identified clinical and echocardiographic predictors of worse clinical outcome despite successful transcatheter mitral valve repair (M-TEER). The capability of invasively measured aortic pulsatility index (API) to predict mortality after successful M-TEER is unclear.

Objective: To assess the impact of API on mortality in patients (pts.) with chronic heart failure (CHF) and severe mitral regurgitation (MR) undergoing M-TEER.

Methods: Consecutive pts. with CHF (left ventricular systolic ejection fraction ≤ 50% from any cause) and severe MR who underwent successful M-TEER (MR ≤2+ at discharge) were included and followed prospectively. Primary endpoint was defined as all-cause mortality during a median follow-up period of 17±12 months. API was calculated as: (systolic blood pressure – diastolic blood pressure) / pulmonary capillary wedge pressure. Receiver operator characteristic (ROC) analysis was used to determine discriminative capacity of API. Kaplan-Meier estimate was used for survival analysis. A multivariable Cox proportional-hazards regression analysis was performed to identify independent risk factors for all-cause mortality.

Results: 217 pts. (median age 75±8 years, 63% male) at high operative risk (LogEuro-SCORE 18.5±15%) were enrolled. Mean API was 1.76±1.3. At long-term follow-up 86 pts. died (39.6%). ROC curve analysis demonstrated that API was associated with an area under the curve of 0.62 (95% confidence interval (CI) 0.53-0.7; p=0.005). An API threshold of 1.76 was associated with 62.3% sensitivity and 41.5% specificity for all-cause mortality. At long-term follow-up, a significantly lower survival rate was observed in pts. with API ≤1.76 (33% vs. 47%; log-rank p=0.01). A cox regression analysis supported the assumption of API (Hazard ratio 0.59; 95% CI 0.39 -0.89; p=0.012) as an independent predictor for all-cause mortality besides NYHA class IV and NT-proBNP levels.
Conclusions: API is strongly associated with mortality among pts. with CHF undergoing successful M-TEER. An API cut-off value of 1.76 predicts mortality independent of other important clinical and echocardiographic factors.