Spain: Cardiac magnetic resonance (CMR) is beneficial over echocardiography for the assessment of LV and AR in patients with isolated AR, finds a recent study in the European Heart Journal. This is because CMR has superior reproducibility and accuracy for grading severity of the disease.
Timely surgery in chronic aortic regurgitation (AR) is reliable mostly on echocardiography. CMR, however, may be more accurate for quantifying left ventricular (LV) remodelling and regurgitation. Esther Pérez-David, Instituto de Investigación Sanitaria Gregorio Marañón, and CIBERCV, Madrid, Spain, and colleagues compared the technical and clinical efficacies of echocardiography and CMR to account for the severity of the disease, the degree of LV remodelling, and predict AR-related outcomes.
For the purpose, the researchers studied 263 consecutive patients with isolated AR undergoing echocardiography and CMR. They were followed for a median of 33 months.
Key findings of the study include:
76 out of 197 initially asymptomatic patients reached the primary endpoint of AR-related events: 6 patients (3%) were admitted for heart failure, and 70 (36%) underwent surgery.
Adjusted survival models based on CMR improved the predictions of the primary endpoint based on echocardiography: R2 = 0.37 vs. 0.22, χ2 = 97 vs. 49, and C-index = 0.80 vs. 0.70.
This resulted in a net classification index of 0.23 and an integrated discrimination improvement of 0.12.
CMR-derived regurgitant fraction (<28, 28–37, or >37%) and LV end-diastolic volume (<83, 183–236, or >236 mL) adequately stratified patients with normal EF.
The agreement between techniques for grading AR severity and assessing LV dilatation was poor, and CMR showed better reproducibility.
"CMR improves the clinical efficacy of ultrasound for predicting outcomes of patients with AR," wrote the authors. "This is due to its better reproducibility and accuracy for grading the severity of the disease and its impact on the LV. Regurgitant fraction, LV ejection fraction, and end-diastolic volume obtained by CMR most adequately predict AR-related events."
The study titled, "A comparison of the clinical efficacy of echocardiography and magnetic resonance for chronic aortic regurgitation," is published in the European Heart Journal.
DOI: https://academic.oup.com/ehjcimaging/advance-article-abstract/doi/10.1093/ehjci/jeaa338/6041050