Computed tomographic assessment of right ventricular long axis strain for prognosis after transcatheter aortic valve...

To investigate the predictive value of right ventricular long axis strain (RV-LAS) derived by cardiac computed tomography angiography (CCTA) for mortality in patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR).

We retrospectively included patients with severe AS undergoing TAVR (n = 168, median 79 years). Parameters of RV function including RV-LAS and RV ejection fraction (RVEF) were assessed using pre-procedural systolic and diastolic CCTA series. The tricuspid annulus diameter (TAD) and diameter of the main pulmonary artery (mPA) were also assessed. All-cause mortality was recorded post-TAVR. Cox regression was used and results are presented with hazard ratio (HR) and 95% confidence interval (CI). Harrell's c-index was used to assess the performance of different models and the likelihood ratio test was used to compare nested models.

Thirty-eight deaths (22.6%) occurred over a median follow-up of 21 months. RV-LAS > -11.42% (HR 2.86, 95% CI 1.44-5.67, p = 0.003), LVEF (HR 0.98, 95% CI 0.96-0.996; p = 0.02), TAD (HR 1.05, 95% CI 1.01-1.10, p = 0.02) and mPA diameter (HR 1.09, 95% CI 1.02-1.16, p = 0.01) were associated with mortality on univariable analysis. In a multivariable model, only RV-LAS (HR 2.36, 95% CI 1.04-5.36, p = 0.04) remained as an independent predictor of all-cause mortality. RV-LAS significantly improved the predictive power of the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) (c-index 0.700 vs 0.637; p = 0.01).

RV-LAS was an independent predictor of all-cause mortality in patients with severe AS undergoing TAVR, outperformed anatomical markers such as TAD and mPA diameter, and could potentially improve the current risk-stratifying tool.