Correlation between frontal QRS-T angle, Tp-e interval, and Tp-e/QT ratio to coronary artery severity assessed with SYNTAX score in stable coronary artery disease patients.

Background: It is known that a wide frontal QRS-T(f[QRS-T]) angle in the electrocardiography (ECG) is associated with poor cardiovascular outcomes. The Tp-e (the interval from the peak to the end of the T wave) interval and Tp-e/QTc ratio show the dispersion of repolarization, and increased levels lead to ventricular arrhythmogenesis in congenital channelopathies and coronary heart disease. In this study, we aimed to investigate the relationship between f(QRS-T), Tp-e interval, and Tp-e/QTc ratio and SYNTAX score in stable coronary artery disease (SCAD) patients.

Methods: A total of 403 patients who performed coronary angiography for SCAD were included. The study population was divided into two groups based on the SYNTAX score. Group 1 included 248 patients (high SYNTAX score > 0), and group 2 included 155 patients (low SYNTAX score = 0). SYNTAX score was calculated using an online SYNTAX score calculator from the coronary angiography images of each patient. The f(QRS-T) angle (QRS angle minus T angle) was calculated from the automated reports of the 12-lead ECG device. Tp-e interval and Tp-e/QTc ratio and other electrocardiographic parameters were recorded.

Results: The mean SYNTAX score in group 1 was 8. F(QRS-T) angle, Tp-e duration, Tp-e/QT, and Tp-e/QTc were significantly higher in group 1 compared with group 2. In the multivariate regression analysis, F(QRS-T) angle and Tp-e duration were independent predictors for SYNTAX scores in SCAD patients.

Conclusions: Our study showed that Tp-e interval, Tp-e/QTc ratio, and f(QRS-T) angle were increased in patients with higher SYNTAX scores in patients with SCAD patients.