Abstract 3212: Prognostic Relevance of Contrast-Enhanced Cardiovascular Magnetic Resonance in Patients with Ischemic Cardiomyopathy
Contrast-enhanced cardiovascular magnetic resonance (ce-CMR) has been shown useful for the assessment of myocardial viability in patients with ischemic cardiomyopathy (ICM). The prognostic relevance of ce-CMR has not been established yet. We hypothesized that ce-CMR could predict cardiac death and hospitalization for heart failure in patients with ischemic cardiomyopathy.
Methods. Between 11/01 and 9/04, 118 consecutive patients (age 42 to 81 years, 20% females) with ICM (EF <50%) and indication for viability testing underwent ce-CMR. Segments with severe wall motion abnormality were assessed for the transmural distribution of hyperenhancement (score 0 to 4). Viability was defined as <50% transmural hyperenhancement (score < 3). In each patient the number of viable segments (VIA) was quantified using a 17 segment model. EF and VIA were dichotomized using ROC analysis for the definition of optimal thresholds. The primary and secondary study endpoints were cardiac death and a combination of cardiac death and hospitalization for heart failure, respectively. Follow-up was determined by direct patient contact, review of hospital records and local population registries.
Results. Mean EF averaged 27±9% and was <35% in 81% of patients. 74% had history of previous myocardial infarction. Mean follow-up was 25±10 months. There were 30 events including 15 deaths and 15 hospitalizations for heart failure. By univariate Cox regression analysis EF (cutoff 26%; p=0.047) and VIA (cutoff 6 segments; p=0.014) predicted cardiac death. In a multivariate Cox regression model including nicotine abuse, number of diseased vessels, end-systolic volume and EF only VIA (p=0.036) remained a predictor for cardiac death. Using Kaplan-Meier analysis and VIA as grouping variable a significant difference in event-free survival between patients with ≥6 VIA compared to patients with <6 VIA was observed (p=0.018). Regarding the secondary endpoint, angina class (p=0.016), renal failure (p=0.01), EF (p=0.033) and VIA (p=0.031) were independent predictors of death or hospitalization.
Conclusions: VIA defined by ce-CMR is a strong predictor of cardiac death in patients with ischemic cardiomyopathy. Ce-CMR predicts cardiac mortality and hospitalization independently of EF.