Cardiovascular magnetic resonance to differentiate veteran athlete's heart with cavity dilatation and mild dilated cardiomyopathy

Abstract Introduction Endurance athletic training may lead to left ventricular (LV) dilatation and mildly reduced resting LV function which can be difficult to differentiate from dilated cardiomyopathy (DCM). Myocardial fibrosis is increasingly recognised in lifelong athletes and is also prevalent in DCM where it confers adverse prognosis.(1,2) However, it is unknown whether the pattern and prevalence of fibrosis in athletes with cavity dilatation differs from DCM. In this study, we compared the CMR fibrosis distribution and tissue characteristics between athletic LV dilatation and mild DCM patients. Methods We prospectively recruited 113 males; 64 endurance athletes and 49 mild DCM patients. Inclusion criteria Age 50-80 years, LVEF 45-54% and LV end-diastolic volume indexed to body surface area (LVEDVi)≥110ml/m2. Athletes trained≥10 weekly hrs for≥15 yrs. Exclusion criteria; Chest pain, prior coronary revascularisation, severe valvular disease, myocarditis, hypertrophic cardiomyopathy, inducible ischaemia or myocardial infarction on CMR. CMR protocol included volumetric assessment, T1 mapping, quantitative stress perfusion and quantitative late gadolinium enhancement. Statistical analysis between groups was performed using unpaired t-test and receiver-operator curve (ROC) analysis. Results LVEDVi was not significantly different between athletes and mild DCM patients (123.3±12.6 vs 129.8±23.1ml/m2, P=0.057). However, LVEF (52.0±6.1 vs 47.6±5.2%, P