Background Recent studies demonstrated that the presence of stenosis on coronary CT angiography has a significant prognostic impact on the prediction of cardiac events. However, data on the prognostic value of whole-heart coronary MR angiography (CMRA) are currently not available. The aim of this study was to determine whether CMRA can predict cardiac events in patients with suspected coronary artery disease (CAD).
Methods We studied 207 patients (68짹10 years; male, 62%) with suspected CAD who underwent non-contrast enhanced free-breathing whole-heart CMRA acquired by using a 1.5T MR system and 32 channel cardiac coils. The presence of ���50% diameter stenosis was visually determined on sliding thin slab MIP images. Adverse cardiac events were defined as cardiac death, myocardial infarction, or unstable angina, and revascularization >90 days.
Results CMRA revealed significant stenosis in 84 (41%) of 207 subjects. During a median follow-up of 25 months (interquartile range, 16 to 33 months), adverse cardiac events were observed in 10 of 84 subjects (11.9%) with significant stenosis on CMRA and 1 of 123 subjects (0.8%) without significant stenosasis, corresponding to the annual event rate of 6.3% and 0.3%, respectively. Kaplan-Meier curve demonstrated a significantly lower event-free survival rate in patients with significant stenosis on CMRA to those without significant stenosis (log-rank test, p<0.001). In multivariate Cox regression analysis, adjusting for age, gender, hypertension, diabetes, hyperlipidemia, smoking, family history of premature CAD, and obesity, the presence of significant stenosis was the independent predictor of adverse cardiac events (adjusted hazard ratio, 17.664; p=0.006).
Conclusions Whole-heart CMRA can reliably predict future risk of cardiac events in patients with suspected CAD without radiation exposure or contrast administration.