Cardiac CTA parameters predict post-transcatheter aortic valve replacement mortality

According to a new article in the American Journal of Roentgenology (AJR), cardiac CTA-derived left atrium emptying fraction (LAEF) improves predictive performance of established clinical risk scores and may be used to assess patients' risk during pre-transcatheter aortic valve replacement (TAVR) workup and postprocedural surveillance.

"LAEF derived from preprocedural cardiac CTA independently predicts mortality in patients with severe aortic stenosis undergoing TAVR," concluded corresponding author U. Joseph Schoepf from the Medical University of South Carolina's Heart and Vascular Center.

Schoepf and colleagues' retrospective single-center study included 175 patients with severe aortic stenosis (92 male, 83 female; median age, 79 years) who underwent cardiac CTA for clinical pre-TAVR assessment. Maximum and minimum left atrium volumes were calculated using biplane area-length measurements, and the values were indexed to body surface area: LAVI_max and LAVI_min, respectively.

In their sample, a reduced LAEF independently predicted all-cause mortality within 24 months post-procedure (hazard ratio 0.97 [0.94–0.99]; p=.02). Moreover, when incorporating LAEF, the c-index of the Society of Thoracic Surgeons Predicted Risk of Mortality significantly increased from 0.64 to 0.70.

Acknowledging that atrial parameters are more commonly assessed using transthoracic echocardiography, both atrial volume and atrial function can be reliably assessed using cardiac CTA, "which now represents the gold standard for preprocedural planning in patients undergoing TAVR," the authors of this AJR article added.