Usefulness of cardiac magnetic resonance in assessing the risk of ventricular arrhythmias and sudden death in patients with hypertrophic cardiomyopathy

To assess the relationship between cardiovascular magnetic resonance (CMR) parameters and both spontaneous ventricular tachycardia (VT) and risk of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) patients. One hundred and eight consecutive HCM patients (mean age 42 +/- 15 years, 76% males) underwent CMR evaluation and risk assessment. Delayed contrast enhancement (DCE) was quantified with a specifically designed score. Endpoints were either the presence of clinical VT/ventricular fibrillation (VF) or of acknowledged risk factors for SCD. Compared to patients without arrhythmia, those with VT/VF (n = 33) had a higher DCE score [median 8 (2-13) vs. 11 (6-20); P = 0.01]; DCE score was also the only independent predictor of VT/VF in the multivariable model. DCE score [median 6 (1-10.5) vs. 12 (6-18); P = 0.001], mean and maximal left ventricular (LV) wall thickness (MaxLVWT), as well as LV mass index were significantly greater among patients at risk for SCD (n = 51) compared with the remaining 57 patients at low risk. DCE score and MaxLVWT were independent predictors of SCD risk. In HCM patients several CMR parameters are associated with risk for SCD. A semi-quantitative index of DCE is a significant multivariable predictor of both clinical VT/VF and of risk for SCD and may contribute to risk assessment in borderline or controversial cases.