Usefulness of Positive T Wave in Lead aVR on Predicting Arrhythmic Events and Mortality in Patients with Hypertrophic Cardiomyopathy

Abstract BACKGROUND Positive T wave in lead aVR (TaVR) has been associated with increased risk of adverse events in various cardiovascular diseases. OBJECTIVE We aimed to investigate the prevalence and prognostic significance of positive TaVR in patients with hypertrophic cardiomyopathy (HCM). METHODS This study investigated consecutive 421 patients with HCM (177 women; 51.1 ± 14.9 years). Admission electrocardiogram was examined for the presence of a positive TaVR. The primary endpoint was defined as composite major arrhythmic event (MAE) that included sudden cardiac death (SCD), sustained ventricular tachycardia or fibrillation or appropriate implantable cardioverter defibrillator (ICD) therapy. Cardiovascular mortality and all-cause death were also evaluated as secondary endpoints. RESULTS During a median follow-up period of 6.0 years (interquartile range: 4.0 to 11.6 years), 53 patients (12.6%) experienced the primary endpoint. On multivariable competing analysis, after adjusting for other confounding factors, the presence of positive TaVR was found to be as an independent and strong predictor of primary composite endpoint. Time-dependent receiver operating characteristic (ROC) analysis, net reclassification index (NRI) and integrated discrimination improvement (IDI) showed that the addition of positive TaVR to conventional HCM risk factors improved prediction of arrhythmic events. However, in subgroup analysis, a positive TaVR lost statistical significance in patients with apical HCM patients but remained significant in all other hypertrophy patterns. CONCLUSION A positive TaVR is associated with MAE in HCM patients, independently of and incremental to traditional risk factors.