Prognostic value of coronary magnetic resonance angiography for prediction of cardiac events in patients with suspected coronary artery disease.

OBJECTIVES: This study sought to determine whether whole-heart coronary magnetic resonance angiography (CMRA) can predict cardiac events in patients with suspected coronary artery disease.
BACKGROUND: Recent studies demonstrated that the presence of stenosis on coronary computed tomography angiography has a significant prognostic impact on the prediction of cardiac events. However, the prognostic value of whole-heart CMRA is unknown.
METHODS: We studied 207 patients with suspected coronary artery disease who underwent non-contrast-enhanced free-breathing whole-heart CMRA acquired with a 1.5-T MR system and 32-channel cardiac coils. The presence of significant coronary stenosis (≥50% diameter reduction) was visually determined on sliding thin- maximum intensity projection images. Follow-up information was obtained for occurrence of severe cardiac events (cardiac death, myocardial infarction, and unstable angina) and all cardiac events (additionally including revascularization>90 days after CMRA).
RESULTS: During a median follow-up of 25 months, 10 cardiac events, of which 5 were severe, were observed in 84 patients with significant stenosis. Whereas, in 123 patients without significant stenosis, only 1 cardiac event with no severe event was observed. Kaplan-Meier curves demonstrated a significant difference in event-free survival between the 2 groups for severe events (annual event rate, 3.9% and 0%, respectively; log-rank test, p = 0.003), as well as for all cardiac events (6.3% and 0.3%; p < 0.001). Cox regression analysis showed that presence of significant stenosis on CMRA was associated with a >20-fold hazard increase for all cardiac events (hazard ratio: 20.78; 95% confidence interval: 2.65 to 162.70; p = 0.001).
CONCLUSIONS: Whole-heart CMRA is useful for predicting the future risk for cardiac events in patients with suspected coronary artery disease.