Coronary magnetic resonance angiography (CMRA) allows non-ionizing visualization of
luminal narrowing in
coronary artery disease (CAD). Although a prior study showed the usefulness of CMRA for risk stratification in short-term follow-up, the long-term prognostic value of CMRA remains unclear. The purpose of this study was to evaluate the long-term prognostic value of CMRA.
METHODS: RESULTS: Obstructive CAD on CMRA was observed in 214 patients (42%). During follow-up (median, 5.6 years), 31
MACE occurred. Kaplan-Meier curve analysis revealed a significant difference in event-free survival between patients with and without obstructive CAD for
MACE (log-rank, p = 0.003) and
cardiac death (p = 0.012). Annualized event rates for
MACE in patients with no obstructive CAD, 1-vessel disease, 2-vessel disease, and left-main or 3-vessel disease were 0.6%, 1.5%, 2.3%, and 3.6%, respectively (log-rank, p = 0.003). Cox proportional hazard regression analysis showed that, among obstructive CAD on CMRA and clinical risk factors (age, sex,
hypertension, diabetes,
dyslipidemia, smoking, and family history of CAD), obstructive CAD and diabetes were significant predictors of
MACE (hazard ratios, 2.9 [p = 0.005] and 2.2 [p = 0.034], respectively). In multivariate analysis, obstructive CAD remained an independent predictor (adjusted hazard ratio, 2.6 [p = 0.010]) after adjusting for diabetes. Addition of obstructive CAD to clinical risk factors significantly increased the global chi-square result from 8.3 to 13.8 (p = 0.022).
CONCLUSIONS: In long-term follow-up, free breathing whole heart CMRA allows non-invasive risk stratification for
MACE and
cardiac death and provides incremental prognostic value over conventional risk factors in patients without a history of
myocardial infarction or prior coronary artery revascularization. The presence and severity of obstructive CAD detected by CMRA were associated with worse prognosis. Importantly, patients without obstructive CAD on CMRA displayed favorable prognosis.