Abstract 19164: Aortic Regurgitation Quantification With Cardiovascular Magnetic Resonance Predicts Clinical Outcome
Background: Current indications for valve surgery in patients with aortic regurgitation focus on symptoms and left ventricular (LV) dilation/dysfunction. Quantifying regurgitation is difficult with echocardiography and has not previously been used to guide patient management. However, cardiovascular magnetic resonance (CMR) can accurately quantify aortic regurgitation, and we examined whether it could predict symptom development and the need for aortic valve surgery.
Methods: In a study involving three high volume CMR centres, 65 asymptomatic patients with at least moderate aortic regurgitation on echocardiography had CMR scans to quantify aortic regurgitation and LV volume indices. They were followed for a mean (±SD) of 40 ±25 months and the best predictors of progression to symptoms and surgery were identified.
Results: Aortic regurgitant volume and fraction were the best predictors of clinical outcome. Receiver operating characteristics analysis showed that regurgitant volume >42mls had a sensitivity of 0.85 and specificity of 0.74 (area under the curve [AUC] 0.85±0.05), while regurgitant fraction >37% had a sensitivity of 0.75 and specificity of 0.87 (AUC 0.84±0.05) for predicting progression to symptoms and surgery. LV volumetric indices also predicted outcome, but less strongly: LV end-diastolic volume AUC 0.81, sensitivity 0.70, specificity 0.82 for >259mls; LV end-systolic volume AUC 0.76 sensitivity 0.75, specificity 0.64 for >92mls. Regurgitant fraction was the only independent outcome predictor on multiple logistic regression analysis (B=10.6, p=0.012). Importantly, survival without surgery was 28% for those with a regurgitant fraction >37%, compared to 89% for patients with a regurgitant fraction <=37% (see graph).
Conclusions: CMR quantification of aortic regurgitation and LV volumes accurately predicts the progression to symptoms/surgery. Its use in patients with aortic regurgitation should be encouraged.
- © 2010 by American Heart Association, Inc.