Relation of T Wave Positivity in Lead aVR to Ischemic Etiology of Cardiomyopathy

Abstract

Identifying ischemic etiology of cardiomyopathy carries prognostic and therapeutic significance. Clinical and electrocardiographic parameters can predict ischemic cardiomyopathy. Positive T wave polarity in lead aVR (TPaVR) has been associated with adverse cardiac events and severity of coronary artery disease. Medical records of adults evaluated in an advanced heart failure referral clinic for cardiomyopathy with systolic dysfunction (ejection fraction ≤ 40%) were retrospectively reviewed. Patients with ventricular pacing were excluded. Significant predictors of ischemic cardiomyopathy from a univariate logistic regression model were entered simultaneously into a multivariate logistic regression model. A total of 180 patients met study inclusion criteria. Mean age of the population was 52.5 ± 15.3 years old and 65% were men. Ischemic cardiomyopathy was present in 52 patients (29%). Positive TPaVR was present in 57 patients (32%). Ischemic cardiomyopathy was more common in patients with positive TPaVR (63% vs 13%, p < 0.001). Ischemic cardiomyopathy was independently predicted by male gender, diabetes, hyperlipidemia, absence of family history of cardiomyopathy, echocardiographic regional wall motion abnormality, and positive TPaVR. The strongest association was with positive TPaVR (odds ratio 30.5, 95% confidence interval 6.47 to 214; p < 0.001). T wave amplitude of +0.025mV in lead aVR was the optimal cutoff to distinguish ischemic and nonischemic cardiomyopathy in receiver operating characteristic analysis (sensitivity 69.2%, specificity 83.6%, area under curve=0.747, 95% confidence interval 0.658 to 0.836). In conclusion, positive TPaVR was a strong predictor of ischemic etiology of cardiomyopathy.