Clinical Outcome in Aortic Regurgitation with Cardiovascular Magnetic Resonance
Background—Current indications for surgery in patients with significant aortic regurgitation (AR) focus on symptoms and left ventricular (LV) dilation/dysfunction. However, prognosis is already reduced by this stage and earlier identification of patients for surgery could be beneficial. Quantifying the regurgitation may help, but there is limited data on its link with outcome. Cardiovascular magnetic resonance (CMR) can accurately quantify AR, and we examined whether this was associated with the future need for surgery.
Methods and Results—113 patients with echocardiographic moderate or severe AR were monitored for up to 9 years (mean 2.6±2.1 years) following a CMR scan, and the progression to symptoms or other indications for surgery was monitored. AR quantification identified outcome with high accuracy: 85% of the 39 subjects with regurgitant fraction >33% progressed to surgery (mostly within 3 years) compared to 8% of 74 subjects with regurgitant fraction ≤33% (p<0.0001); area under the curve on receiver operating characteristic analysis 0.93 (p<0.0001). This ability remained strong on time-dependent Kaplan-Meier survival curves. CMR-derived end-diastolic volume (LVEDV) >246ml had good, though lower, discriminatory ability (AUC 0.88) but the combination of this with regurgitant fraction provided the best discriminatory power.
Conclusions—High degrees of CMR-quantified AR were associated with the development of symptoms or other indications for surgery. Quantifying AR showed slightly better discriminatory ability than 'Gold-standard' CMR ventricular volume assessment. This could provide a new paradigm for the timing of surgical intervention but requires confirmation in a clinical trial.
- aortic regurgitation
- aortic valve replacement
- cardiovascular magnetic resonance imaging
- Received November 30, 2011.
- Accepted July 30, 2012.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited