Predictors for mitral regurgitation improvement in patients with pure severe aortic regurgitation undergoing transcatheter aortic valve replacement: when can kill two birds with one stone?

Abstract Objective Transcatheter aortic valve replacement (TAVR) has been recognized as a significant treatment for pure severe aortic regurgitation (PSAR). Part of patients with PSAR concurrently suffer from functional mitral regurgitation (FMR). Whether TAVR could improve FMR in patients with PSAR and the predictors have not yet been clarified. This study aims to explore predictors of FMR improvement in patients with PSAR undergoing TAVR and subsequently provide evidence for further clinical therapy. Method Patients with PSAR and FMR who underwent TAVR at Zhongshan Hospital Affiliated with Fudan University were enrolled from June 2021 to August 2023. Depending on whether FMR improved one month post-TAVR, they were divided into groups with or without FMR improvement. The baseline data, imaging results, and follow-up data of the patients were collected. Result This study included 75 patients, among whom 38 patients had improved FMR and 37 patients did not. Compared to patients without FMR improvement, more patients in the FMR-improved group were diagnosed with renal insufficiency (10.8% vs. 0%, p=0.018), left bundle branch block (8.1% vs. 0%, p= 0.037), and less right bundle branch block (0% vs. 10.5%, p=0.017). The transthoracic ultrasound examination showed that patients with FMR improvement were prone to have lower left ventricular ejection fraction (LVEF) and larger left ventricle end dimension diastole (LVEDd). A higher proportion of patients in the FMR-improved group were found to have had more moderate to severe FMR (28.9% vs. 2.7%, P=0.029). In both groups, the degree of aortic regurgitation was significantly improved during the 1-day and 1-month follow-ups post-TAVR (p<0.001). No significant differences were found in the incidence of postoperative adverse events between the two groups during the short-term follow-up. Conclusion FMR improvement is observed in approximately half of PSAR patients undergoing TAVR. A higher FMR degree, lower LVEF, and hypertension before TAVR are independent predictors of FMR improvement.Figure 1 AR and MR post TAVRTable 1 Logistic regression