Impact of preprocedural echocardiographic parameters on increased stroke volume after transcatheter aortic valve replacement

Aims: Increased stroke volume (SV) is a prognosticator of severe aortic stenosis (AS) after transcatheter aortic valve replacement (TAVR). This study aimed to investigate preprocedural echocardiographic predictors of increased SV after TAVR. Methods and results: Clinical and echocardiographic data were retrospectively analysed in 129 patients with severe AS who underwent TAVR (2013-2015). We compared the echocardiographic data and cardiac events between the decreased SV group (n=28) and the increased SV group (n=101). Univariate and multivariate analyses were used to assess the predictors of increasing SV. AS severity significantly diminished, left and right ventricular function improved, and SV index (SVi) increased after TAVR: aortic valve area index (0.46±0.13 vs. 1.18±0.33 cm2, p<0.001); aortic regurgitation (AR) grade (1.85±0.55 vs. 1.60±0.54, p<0.001); left ventricular ejection fraction (59.9±12.7 vs. 64.1±12.0%, p<0.001); right ventricular fractional area change (RVFAC) (48.8±11.9 vs. 53.3±14.0%, p<0.001); SV index (SVi) (46.7±11.0 vs. 52.8±12.0 ml/m2, p<0.001). Kaplan-Meier survival estimates suggested that the SVi increase was associated with the decreased cardiovascular events one year after TAVR (hazard ratio 4.08, 95% confidence interval [CI]: 1.32-12.7, p=0.02). On multivariate analysis, preprocedural AR grade (odds ratio [OR] 7.00, 95% CI: 2.76-17.8, p<0.001) and preprocedural RVFAC (OR 1.05, 95% CI: 1.01-1.10, p=0.011) correlated with the SV increase. Conclusions: Preprocedurally, greater AR and higher RVFAC could predict an increased SVi and thus the occurrence of fewer cardiac events. Preserved preprocedural RV systolic function is crucial for an increased SV after TAVR.