Influence of the ratio of mean arterial pressure to right atrial pressure on outcome after successful percutaneous edge-to-edge repair for severe mitral valve regurgitation

Background: It is important to identify further predictors of outcome after successful transcatheter mitral valve repair (TMVR), as optimal patient selection remains difficult. Objective: The study investigates the prognostic benefit of the mean arterial pressure (MAP) to right atrial pressure (RAP) ratio (MAP/RAP ratio) after successful TMVR in patients with congestive heart failure (CHF) and severe mitral regurgitation (MR). Method: Patients with CHF and severe MR were enrolled after successful TMVR (MR <= 2+ at discharge). The primary endpoint was a composite of all-cause mortality or hospitalisation for heart failure. The median followup time was 16 +/- 9 months. Receiver Operating Characteristic (ROC) analysis was applied to assess the discriminatory power of the MAP/RAP ratio. The predictive value of the MAP/RAP ratio threshold was investigated using a Kaplan-Meier analysis. Multivariable logistic regression analysis was conducted to evaluate independent risk factors for the combined primary endpoint. Results: 145 patients (median age 76 [69-80 years], 60.3% male) were included. ROC curve analysis showed that MAP/RAP ratio was associated with an area under the curve of 0.62 (95% confidence interval (CI) 0.53-0.71; p = 0.01). A MAP/RAP ratio threshold of 7.13 was associated with 67.4% sensitivity and 57.0% specificity for the combined primary endpoint. Event-free survival was significantly lower in the MAP/RAP ratio < 7.13 group compared to those with MAP/RAP ratio >= 7.13 (62.2% versus 39.4%; log-rank p = 0.022). In logistic regression analysis MAP/RAP ratio was an independent predictor for the combined primary endpoint (odds ratio 0.75; 95% CI 0.62-0.90; p = 0.002). Conclusions: The MAP/RAP ratio is associated with an unfavorable outcome in patients undergoing successful TMVR. Therefore, this new index could improve prognostic assessment of TMVR candidates.