Factors Associated With Increased Risk for AVR, Death in Aortic Stenosis

Atrial fibrillation, left ventricular ejection fraction (LVEF), abnormal right ventricular function, and ventricular hypertrophy were found to be associated with a greater risk for aortic valve replacement (AVR), death, or hospitalization for heart failure in patients with moderate aortic stenosis, according to a study published in The American Journal of Cardiology.

In this retrospective single-center study, 151 patients (age ≥18 years; index echocardiogram between 2014 and 2017) with moderate aortic stenosis were enrolled. Aortic stenosis was defined as maximum transvalvular velocity between 3.0 and 4.0 m/s, dimensionless index between 0.25 and 0.50, mean transvalvular pressure gradient between 20 and 40 mmHg, and valve area between 1.0 to 1.5 cm². Composite end points were hospitalization for heart failure, AVR, or all-cause death. The time to event for each end point was analyzed using Kaplan-Meier analysis, and independent risk factors for each composite end point were identified using multivariable Cox proportional hazards. 

The most common end point was transcatheter aortic valve implantation or surgical AVR, which occurred in 51% of participants (n=77), hospitalization for heart failure, which occurred in 20% of patients (n=30), and all-cause death (9%; n=13).

The composite outcomes of AVR or hospitalization for heart failure and the composite of hospitalization for heart failure, AVR, or all-cause death, which occurred in 61% and 66% of participants, respectively (n=93 and n=99, respectively), were found to be associated with reduced ejection fraction (hazard ratio [HR], 4.1; 95% CI, 2.3-7.1; P <.001, and HR, 3.8; 95% CI, 2.2-6.6; P <.001, respectively), reduced aortic valve area (HR, 0.3; 95% CI, 0.1-0.6; P =.003, and HR, 0.25; 95% CI, 0.1-0.6; P =.001, respectively), atrial fibrillation (HR, 2.0; 95% CI, 1.2-3.2; P =.006, and HR, 2.1; 95% CI, 1.4-3.2; P =.001, respectively), abnormal right ventricular function (HR, 5.5; 95% CI, 3.0-9.8; P <.001, and HR, 4.3; 95% CI, 2.5-7.5; P <.001, respectively), and higher aortic valve mean gradient (HR, 1.06; 95% CI, 1.03-1.09; P <.001, and HR, 1.05; 95% CI, 1.02-1.08; P =.001). 

Study limitations include its retrospective design, a lack of accounting for the variable durations of moderate aortic stenosis prior to the first echocardiogram, and the reliance on echocardiographic assessments for the classification of aortic stenosis.  “[O]ur study identified LVEF, atrial fibrillation, left ventricular hypertrophy, and abnormal [right ventricular] function as associated with [heart failure] hospitalization, AVR or death in patients with ]moderate aortic stenosis],” noted the study authors.

Reference

Murphy KR, Khan OA, Rassa AC, et al. Clinical and echocardiographic predictors of outcomes in patients with moderate (mean transvalvular gradient 20 to 40 mmHg) aortic stenosis [published online October 2, 2019]. Am J Cardiol. doi: j.amjcard.2019.09.022