Abstract 11107: The ECG has a Low Diagnostic Yield in Active Individuals With Dilated Cardiomyopathy

Abstract

Introduction/Objective: Around 90% of patients with HCM have an abnormal ECG; however there is paucity of data on the ECG in DCM. Approximately 14% athletes show an LV cavity >60mm and 1-2% reveal a borderline low LVEF which overlaps with DCM. The role of ECG in facilitating the differentiation between physiologic LV enlargement and DCM has not been investigated. We sought to ascertain the utility of the various ECG screening criteria in differentiating physiology from pathology in a cohort of individuals with LV dilatation. Methods: 89 individuals with a dilated LVEDD (43 asymptomatic athletes from cardiac screening (male=37, female=6) and 46 non-ischaemic DCM NYHA class I from a cardiomyopathy clinic (males=33, female=13) were included. Fourty (87%) of the DCM patients were on a beta-blocker. The 2010 ESC, ‘Seattle’ and the novel ‘Refined’ screening criteria were applied to the most recent ECG in both cohorts to assess whether ECG screening would have accurately raised suspicion of pathology. Results: Using the ESC criteria 11 DCM patients had a normal ECG and 6 had group 1 changes; therefore 40.0% of DCM patients would have been considered to have an ECG compatible with athletic training. Excluding sinus bradycardia, the most common group 1 change was early repolarisation. The sensitivity and specificity of the ESC criteria for detecting pathology in our cohort was 63.0% and 69.0% respectively. The sensitivity and specificity of the ‘Seattle’ criteria is 50% and 76.7%. The ‘Refined’ criteria was less sensitive at 41.3% but had a higher specificity of 79.2%. Conclusions: It is often assumed the ECG is abnormal in patients with a dilated cardiomyopathy. In our cohort 40% of the ECGs in our DCM patients would have not prompted further investigation if seen at pre-participation screening. This study demonstrates the ECG is not a particularly useful investigation in distinguishing physiological from pathological LV dilatation.