ARRS 2022 Abstracts


1874. Pre-Procedural CTA-Based Left Atrial Function Independently Predicts Mortality in Transcatheter Aortic Valve Replacement
Authors * Denotes Presenting Author
  1. Tilman Emrich; Medical University of South Carolina
  2. Gilberto Aquino *; Medical University of South Carolina
  3. Rock Savage; Medical University of South Carolina
  4. Logan Fitzpatrick; Medical University of South Carolina
  5. Akos Varga-Szemes; Medical University of South Carolina
  6. U. Joseph Schoepf; Medical University of South Carolina
This study aims to assess the predictive value of pre-procedural, multiphasic cardiac CT-based left atrial (LA) volume (LAV) and function for all-cause mortality in patients undergoing transcatheter aortic valve replacement (TAVR).

Materials and Methods:
One hundred and seventy-five patients (78.8 ± 8.9 years) with severe aortic stenosis who had previously undergone TAVR were retrospectively evaluated. All-cause mortality was the primary endpoint over a 24-month follow up period. Pre-TAVR CTAs with 10-100% phases were analyzed using the area-length method to measure maximum and minimum LAV in 2-chamber and 4-chamber views, and indexed LAV (LAVI = LAV/BSA) were then used. LA emptying fraction (LAEF) was obtained as (LAVmax - LAVmin)/LAVmax. LAVI and LAEF were divided into quintiles for analysis. Cox regression was performed for survival analysis to obtain hazard ratios (HR) and Harrell’s c-index was used to evaluate risk models. LAV and LAEF were each adjusted according to the Society of Thoracic Surgeons (STS) score for mortality currently used to risk stratify TAVR patients.

Median follow-up was 21 months. There were 38 deaths (22%). LAEF (HR 0.69; 95% CI 0.49-0.97; p=0.035; per quintile) was independently associated with mortality after adjustment for variables predictive on univariable analysis. LAVImax (HR 1.25; 0.93 - 1.69; p=0.147; per quintile) and LAVImin (HR 1.35; 0.90 - 2.03; p=0.147; per quintile) were not significant when adjusted for all of these confounders. When adjusted for the STS risk score, LAVImax (HR 1.32; 1.04 - 1.69; p=0.025), LAVImin (HR 1.42; 1.10 - 1.84; p=0.007), and LAEF (HR 0.73; 0.57 - 0.94; p=0.016) were significantly predictive for mortality. LAVImax, LAVImin, and LAEF had a c-index of 0.633, 0.668, and 0.667 for prediction of death, respectively, while STS score had a c-index of 0.636. Adding LAEF to the STS score significantly improved its c-index to 0.700 for prediction of mortality.

Pre-TAVR, CTA-based LA volume and LA emptying fraction independently predict mortality post-TAVR and improve the current clinical risk-stratifying tool.