Predictors of Progression in Patients With Stage B Aortic Regurgitation

Abstract

Background: The natural history of stage B aortic regurgitation (AR) is unknown.

Objectives: This study sought to examine determinants, rate, and consequences of progression of AR.

Methods: Consecutive patients with ≤moderate chronic AR quantified by effective regurgitant orifice area (EROA) and regurgitant volume (RVol) from 2004 to 2017 who had ≥1 subsequent echocardiogram with quantitation were included.

Results: Of 1,077 patients (66 ± 15 years of age), baseline trivial/mild AR was noted in 196 (18%), mild-to-moderate AR in 465 (43%), and moderate AR in 416 (39%); 10-year incidence of progression to ≥moderate-severe AR (stage C/D; progressors) was 12%, 30%, and 53%, respectively. At 4.1-year follow-up (interquartile range: 2.1 to 7.2 years), there were 228 progressors (21%), whose annualized progression rates within 3 years before diagnosis of ≥moderate-severe AR were 4.2 mm²/year for EROA and 9.9 ml/year for RVol. Baseline AR severity and dimensions of sinotubular junction and annulus were associated with progression (all p ≤ 0.007); hypertension and systolic blood pressure were not. Progressors had faster chamber remodeling, functional class decline, and more aortic valve/aortic surgery. At medium-term follow-up, 242 patients (22%) died; poor survival was linked to age, comorbidities, functional class, resting heart rate, and left ventricular (LV) ejection fraction (p ≤ 0.003), not LV end-systolic dimension index. Survival after progression to stage C/D AR was associated with LV end-systolic dimension index (adjusted p = 0.02).

Conclusions: Progression from stage B to stage C/D AR was observed in 21% patients. Repeat echocardiography for trivial/mild, mild-to-moderate, and moderate AR at every 5, 3, and 1 years, respectively, was reasonable. EROA, RVol, annulus, and sinotubular junction should be routinely measured to estimate progression rates and identify patients at high risk of progression, which was associated with adverse consequences.

Keywords: aortic regurgitation; echocardiography; prognosis; progression.