Abstract 14851: Risk Factors and Clinical Effects of Leaflet Thrombosis After Transcathether Aortic Valve Replacement

Abstract

Introduction: The incidence of leaflet thrombosis is higher in TAVR than in SAVR; however, knowledge regarding the risk factors of leaflet thrombosis in TAVR is limited. Hypothesis: In this study, the incidence and risk factors for leaflet thrombosis after TAVR and its effects on clinical course were investigated. Methods: 176 patients who underwent TAVR from January 2015 to October 2020 were enrolled. Follow-up MDCT was performed between 3 months and 2 years after TAVR in 94 patients. Among the 94 patients, leaflet thrombosis occurred in 20 patients, and risk factors were analyzed by comparing clinical factors, echocardiographic parameters, 4D-MDCT information, and angiographic data between thrombosis group and no thrombosis group. Clinical outcome was defined as the composite of all-cause death, stroke, HF admission, redo AVR, and major bleeding after detection of leaflet thrombosis. Results: Indexed mean SOV diameter, AV calcium volume, and post-procedure EOAi were predictive of leaflet thrombosis with AUC value of 0.670 (95% CI 0.546 - 0.795, P -value = 0.020), 0.695 (95% CI 0.541 - 0.850, P -value = 0.012), and 0.665 (95% CI 0.548 - 0.782, P -value = 0.031), respectively. In echocardiography performed at the time of follow-up CT, the value of AV max velocity and AV mean pressure gradient were higher in the thrombosis group and the EOAi and Doppler velocity index values were lower in the thrombosis group than in the no thrombosis group. All the median echocardiographic values in both groups were within normal range. All patients with leaflet thrombosis were in subclinical status and half changed medication after detection. Clinical outcome was not significantly different between the two groups (log-rank P -value = 0.26). Conclusions: Larger indexed SOV diameter, higher AV calcium volume, and smaller post-procedure AV EOAi were risk factors for leaflet thrombosis after TAVR. Subclinical leaflet thrombosis has a benign course when properly managed.