Mitral paravalvular leak (PVL) is associated with hemolysis and heart failure. It has also been linked to shear stress-induced von Willebrand factor abnormalities that prolong closure time with adenosine diphosphate (CT-ADP). The aim of this study was to assess whether CT-ADP serves as a biomarker for mitral PVL diagnosis, follow-up, and prognosis after repair.

In this prospective study, 89 patients (27 with moderate-to-severe mitral PVL referred for closure, group 1; 31 with prosthetic mitral valves without PVL, group 2; and 31 controls without valvular disease, group 3) underwent laboratory assessment including hemolysis markers, congestion markers, and CT-ADP. Patients with PVL underwent percutaneous or surgical repair and were followed up at 3 and 12 months. ROC analysis, linear regression, and Cox models were used to evaluate the diagnostic and prognostic value of CT-ADP.

CT-ADP was prolonged in PVL patients (median, 214seconds) vs control groups (86 seconds in group 2 and 74seconds in group 3; P <.001). A cutoff of> 135seconds showed excellent diagnostic accuracy (AUROC, 0.96; sensitivity 89%, specificity 97%). Postprocedural CT-ADP decreased significantly after successful repair (median decrease of 79seconds) but remained unchanged in those with residual leaks. Elevated postprocedural CT-ADP (>155 s) identified persistent PVL and was associated with worse 1-year outcomes (HR, 21.37; P=.004), including death, heart failure or hemolysis-related readmission, and reintervention.

CT-ADP appears to be a promising biomarker for diagnosing and monitoring mitral PVL. It may add value to conventional markers by reflecting shear stress-related platelet dysfunction and predicting outcomes following PVL closure.