Higher product of right ventricle to left ventricle diameter ratio and septal wall thickness is associated with increased risk of cardiovascular death in patients post TAVI

Abstract Background Right ventricular (RV) dilatation is a significant predictor for mortality in various cardiovascular diseases. Hypertrophy is common in patients undergoing transcatheter aortic valve implantation (TAVI). We tested the hypothesis that the product of right ventricle to left ventricle diameter (RV/LV) ratio and septal wall thickness (SWT) might be a determinant of cardiovascular death in TAVI patients. Methods This retrospective study enrolled 1123 patients undergoing TAVI in our department between 2009 and 2021 (mean age 81.4±5.6 year, male 51.2%). We assessed standard echocardiographic measures prior to the TAVI procedure. End-diastolic basal biventricular dimensions were measured from a standard apical 4-chamber view, and the ratio of RV dimension (RVD) to LV dimension (LVD) was calculated as the RV/LV ratio. We tested the prognostic performance of the product of RV/LV ratio and septal wall thickness (RV/LV ratio*SWT). The primary endpoint was cardiovascular (CV) death up to 2 years after TAVI. Results CV mortality was 11.8% (132/1123) at 2 years after TAVI. SWT was similar between the groups with and without CV death (11.9±1.9 vs. 11.6±1.8 mm, P=0.188). However, the RV/LV ratio (0.84±0.15 vs. 0.80±0.13, P=0.002) and RV/LV ratio*SWT (10.0±2.7 vs. 9.3±3.1 mm, P=0.005) were notably higher in the CV-death group compared to the no CV-death group. Higher RV/LV ratio*SWT remained independently associated with elevated 2-year CV mortality after TAVI (HR=1.09, 95% CI 1.01-1.17, P=0.024), while the RV/LV ratio was no longer significantly linked with CV mortality (HR=2.83, 95% CI 0.87-9.19, P=0.082) after adjusting for potential confounding factors including age, sex, and atrial fibrillation. RV/LV ratio*SWT >12.7 mm was associated with a twofold increased risk of 2-year CV mortality compared to patients with RV/LV ratio*SWT ≤12.7 mm (2-year mortality 14.4% vs. 6.0%, P<0.001; HR=2.04, 95% CI 1.25-3.32, P=0.004), regardless of age, sex, and atrial fibrillation. Conclusions Combined assessment of biventricular remodelling and left ventricular hypertrophy by calculating RV/LV ratio*SWT is of clinical importance for risk stratification of cardiovascular death among TAVI patients.