T2 Mapping Cardiovascular Magnetic Resonance Is an Independent Predictor of Adverse Outcome in Hypertrophic Cardiomyopathy

INTRODUCTION: The outcome of patients with hypertrophic cardiomyopathy (HCM) largely depends on the presence of ventricular arrhythmias. T2 mapping is a well-documented cardiovascular magnetic resonance (CMR) sequence for edema evaluation and quantification. Our aim was to evaluate whether T2 mapping values might predict ventricular arrythmias and clinical outcome in patients with HCM. METHODS: Consecutive patients (n = 48, mean age 50 ± 18 years) with HCM and healthy volunteers (n = 21, mean age 44 ± 5 years) underwent a CMR scan (3 Tesla scanner). T2 mapping values were presented using a 16-segment AHA model and divided into 3 tertiles. Late gadolinium enhancement (LGE) was calculated as percentage of left ventricular mass. Ventricular tachycardia (VT) was recorded by 24-h Holter monitoring or during exercise stress test. The clinical endpoint was defined as the presence of VT, admission due to arrhythmias, and implantable cardioverter defibrillator insertion. RESULTS: The clinical endpoint was documented in 69%, 62%, and 50% of the third, second, and first T2 mapping tertiles, respectively (p for trend = 0.03). A multivariate analysis including age, gender, LGE, and T2 mapping demonstrated that T2 mapping was an independent predictor of the clinical endpoint as a continuous variable (OR 1.56; 1.03-2.38, p = 0.04) and the third T2 tertile (OR 22.80; 1.40-361.60, p = 0.03), respectively. CONCLUSION: Elevated T2 mapping values were found to be an independent predictor of the clinical endpoint in HCM patients. These results highlight the potential role of edema in HCM arrhythmias.