Abstract 16996: Relationship of Paravalvular Leak and Mean Platelet Volume With Stroke Risk Following Transcatheter Aortic Valve Replacement

Abstract

Introduction: Stroke remains a major complication patients may face following Transcatheter Aortic Valve Replacement (TAVR). It has been hypothesized that turbulent flow across persistent paravalvular leak (PVL) may lead to low level hemolysis, a state known to heighten serum thrombotic potential and increase stroke risk. We hypothesized that the presence of paravalvular leak would lead to elevations in serum mean platelet volume (MPV), a marker of platelet activation and aggregation, and thus would heighten stroke risk after TAVR. Methods/Results: We retrospectively reviewed the charts of 322 patients who underwent TAVR at Montefiore Medical Center from January 2015 to January 2019. Stroke was seen in 24 patients (7%) following TAVR and was associated with higher overall mortality (p=<0.001). PVL was recorded in scaling severity of “none”, “trace”, “mild”, “moderate”, and “severe”. “Significant PVL”, defined as the presence of “mild” or greater PVL on initial post-op transthoracic echocardiogram, was found in 72 patients (22.4%). No associations were seen between the presence of significant PVL and stroke after TAVR. Serum MPV values after TAVR were not associated with the presence of significant PVL, nor with an increase in the observed rate of stroke or death on follow-up. Conclusions: Stroke after TAVR is significantly associated with increased mortality. In our dataset, the presence of significant PVL was not associated with increased rate of stroke or elevated serum MPV levels post-TAVR. Moderate and severe PVL are known to generate the greatest amount of hemolysis and were rare in our dataset (combined 1.5%), likely contributing to the lack of significant findings.