[Risk factors of perivalvular leakage after transcatheter aortic valve replacement with Venus-A valve]

Objective: To investigate the risk factors of moderate or severe perivalvular leakage (PVL) after transcatheter aortic valve replacement (TAVR) with Veneus-A valve. Methods: This study was a single-center case-control study. The clinical data of patients with severe aortic stenosis, who underwent TAVR in the Department of Cardiology of Second Affiliated Hospital of Army Medical University from October 2017 to January 2021, were analyzed. According to the circumferential extent of prosthetic valve paravalvular regurgitation measured by transthoracic echocardiography before discharge (patients who died in hospital were referred to transesophageal echocardiography results after valve implanted), the patients were divided into moderate or severe PVL group and mild or non-PVL group. The clinical features, CT scan and analysis results of aortic root were compared between the two groups. Multivariate logistic regression analysis was used to identify the independent risk factors of postoperative moderate or severe PVL, and receiver operating characteristic (ROC) curve was used to explore the predictive value of related factors. Results: Eighty-two patients (mean age: (70.9±6.5) years, 46 males) were included in the analysis, there were 16 patients in the moderate or severe PVL group and 66 patients in the mild or non-PVL group. The proportion of male gender, depth of valve implantation, size of valve annulus and left ventricular outflow tract (LVOT), and coverage index of LVOT were significantly higher in moderate or severe PVL group than those in mild or non-PVL group (Pall<0.05). As there was a strong collinearity among the valve annular short diameter, LVOT short diameter and LVOT coverage index (partial correlation coefficient R 0.251-0.779, P<0.05), these parameters were not entered in regression model. Multivariate logistic regression analysis showed that valve implantation depth(OR=1.239,95%CI 1.036-1.442,P=0.023), aortic angulation(OR=1.128, 95%CI 1.044-1.312,P=0.038)and LVOT tract coverage index (OR=1.123, 95%CI1.003-1.315, P=0.032) were independent risk factors for moderate or severe PVL after TAVR. The ROC curve showed that the valve implantation depth could predict the occurrence of moderate or severe PVL after TAVR (area under ROC curve (AUC)=0.697, 95%CI 0.554-0.851, P=0.039). Conclusion: Among patients with severe aortic stenosis who undergo TAVR with Venus-A valve, the implantation depth, aortic angulation and LVOT coverage index are independent risk factors of moderate/severe PVL after TAVR, among which valve implantation depth could be used to predict the occurrence of moderate/severe PVL after TAVR.