Hence, multivariate Cox proportional-hazards regression analysis was performed for NT-pro-BNP and atrial fibrillation and identified history of atrial fibrillation (hazard ratio 2.39, 95% confidence interval 1.06–5.41; p = 0.036, Table 6) as independent predictor of mortality after adjustment for NT-pro-BNP (p = 0.072) levels in patients undergoing MitraClip implantation for severe MR. Here, NPPB is linked to atrial fibrillation.