Evaluation of Tp-Te interval and Tp-Te/QTc ratio in patients with coronary artery ectasia

Coronary artery ectasia (CAE) is commonly defined as local or generalized dilatation of a coronary vessel up to 1.5 times the diameter of an adjacent vessel. Tp-Te interval and Tp-Te/QT ratio have emerged as novel electrocardiographic markers of increased dispersion of ventricular repolarization. The aim of this study was to evaluate ventricular repolarization by using Tp-Te interval and Tp-Te/QT ratio in patients with CAE.

Patients' records were retrospectively analyzed. Electrocardiogram of 28 patients, who were diagnosed as CAE were obtained and scanned. T wave peak to end interval, QT and corrected QT intervals and some other ECG intervals were measured. Electrocardiograms of age and sex matched 22 control individuals were also analyzed for comparison. Patients with critical coronary stenosis, moderate or severe valve disease, left and/or right heart failure, left and/or right ventricle hypertrophy, atrial fibrillation, moderate or severely abnormal electrolytes, right or left bundle block or patients who got pacemaker or ICD implanted and who undergo hemodialyses were excluded.

Baseline characteristics and QT, QTc intervals were similar in both groups. Tp-Te (97.71 ± 8.7 vs 85.23 ± 7.1; p < 0.001) and Tp-Te/QT (0.22 ± 0.0 vs 0.20 ± 0.0; p < 0.001) were significantly worse in CAE group.

T wave peak to end interval is a measure of transmural dispersion of repolarization in the left ventricle and accepted as a surrogate for increased ventricular arrhythmogenesis risk. Tp-Te and Tp-Te/QT are relatively new markers which also indicate repolarization defects. Our results show that CAE patients significantly higher values of Tp-Te and Tp-Te/QT than controls. These measurements may indicate increased arrhythmogenesis risk for individuals with CAE.