Aortic Regurgitation Quantification Using Cardiovascular Magnetic Resonance: Association With Clinical Outcome

Oct 29, 2012
Font Size
A
A
A
Authors:
Myerson SG, d’Arcy J, Mohiaddin R, et al.
Citation:
Circulation 2012;126:1452-1460.
Summary By:
Troy M LaBounty, MD, FACC

Study Questions:

Amongst asymptomatic individuals with moderate or severe aortic regurgitation (AR) by echocardiography, are cardiac magnetic resonance imaging (CMR) findings associated with future need for aortic valve surgery?

Methods:

This study examined 113 asymptomatic patients from four sites undergoing CMR with isolated moderate or severe AR by echocardiography, and examined the relationship between CMR findings and aortic valve surgery for established indications at least 2 months following the CMR exam.

Results:

Over a mean follow-up of 2.6 ± 2.1 years, 39 patients (35%) underwent aortic valve surgery for established indications, including new symptoms (n = 19), left ventricular (LV) dilatation (n = 17), or reduced LV function (n = 3). CMR measures that were independent predictors of aortic valve surgery included regurgitant fraction (p < 0.001), regurgitant volume (p < 0.001), and left ventricular end-diastolic volume (p = 0.002). A regurgitant fraction >33% had a sensitivity of 85% and a specificity of 92% to identify patients who would progress to surgery (area under receiver operating curve 0.93, p < 0.001), and surgery-free survival was 93% and 34% for regurgitant fractions ≤33% and >33%, respectively (p < 0.001). A left ventricular end-diastolic volume >246 cc was also associated with good discriminatory ability (area under curve 0.88, p < 0.001).

Conclusions:

CMR measures of AR severity and LV size were predictive of future need for aortic valve surgery in asymptomatic individuals with moderate or severe AR by echocardiography.

Perspective:

This study demonstrates that CMR has very good discriminatory ability to identify asymptomatic individuals who are likely to progress to aortic valve surgery within an intermediate-term follow-up (mean 2.6 years). The relative discriminatory ability of these findings by MRI in comparison to quantified measures of AR, LV size, and LV function by echocardiography are not established and should be evaluated in future studies.

Keywords: Follow-Up Studies, Ventricular Function, Left, Mitral Valve Insufficiency, Dilatation, Cardiovascular Diseases, Stroke Volume, Magnetic Resonance Imaging, Echocardiography


< Back to Listings