Abstract 4337522: Prognostic Impact of Right Ventricle-Pulmonary Artery Coupling in Patients with Severe Calcific Mitral Stenosis

Background: Right ventricular function is strongly associated with the mortality in mitral stenosis (MS). The ratio of tricuspid annular plane systolic excursion (TAPSE)/pulmonary artery systolic pressure (PASP) serves as a noninvasive measure of right ventricle-pulmonary artery (RV-PA) coupling, which reflects the ability of RV to handle a given pulmonary afterload. Our aim is to assess the relationship between TAPSE/PASP and outcomes in calcific MS. Methods: A single-center retrospective cohort study was performed. Patients diagnosed with calcific MS on echocardiography between October 2010 and August 2020 were identified. We included patients with severe calcific MS due to mitral annular calcification (MAC) who had TAPSE and PASP measurements available. Propensity score (PS) was performed using a logistic regression model, with TAPSE/PASP >0.45 as the dependent variable and seven clinically relevant covariates (age, sex, NYHA class, hypertension, atrial fibrillation, Charlson comorbidity index, left ventricular ejection fraction). After PS matching, we compared all-cause mortality between the two groups. Outcomes: Of 7,154 patients with MS, 229 patients with severe calcific MS were included (72 with TAPSE/PASP >0.45 and 157 with TAPSE/PASP ≤0.45). In the entire cohort, the mean age was 72 ± 11 years and 65.9% were female. During the median follow-up duration of 345 days (25 th -75 th percentile: 80 – 851 days), 80 patients (34.9%) underwent mitral valve surgery, and there were 74 (32.3%) deaths. The cumulative survival of patients with TAPSE/PASP ≤0.45 was lower than patients with TAPSE/PASP >0.45 in the entire cohort (p = 0.001), the conservative treatment group (p = 0.023), and the mitral valve intervention group (p = 0.020). After PS matching in 144 patients (72 patients in each group), similar results were obtained (p = 0.002, p = 0.028, p = 0.021). Conclusion: TAPSE/PASP is strongly associated with all-cause mortality in patients with severe calcific MS. This relationship was also observed after PS matching, suggesting this is a valuable non-invasive marker in calcific MS.