RÉSUMÉ
Objective: The present study was undertaken to investigate the prognostic value of the frontal planar QRS-T angle in patients without angiographically apparent coronary atherosclerosis
Subjects and Methods: Three hundred and seven patients with normal coronary arteries on coronary angiography were included. The absolute difference between the frontal QRS- and T-wave axes was defined as the frontal planar QRS-T angle, and patients were divided into 3 subgroups based on the frontal planar QRS-T angle [<45, 45-90, and >90]. Demographic, clinical, laboratory, and angiographic data were compared between groups. Based on the regression analysis results, patients were recategorized into 4 groups according to their luminal calibers of left main coronary artery [LMCA] and history of hypertension [HT] [nonhypertensive LMCA 4.13 mm, hypertensive LMCA 4.13 mm]
Results: The median value of the frontal planar QRS-T angle of all participants was 38°. Subjects with the widest frontal planar QRS-T angle were older [p = 0.027], were hypertensive [p = 0.001], and had higher corrected QT values [p = 0.001]. Patients with the widest frontal planar QRS-T angle had larger LMCA and left anterior descending coronary artery diameters compared to subjects with a normal and borderline frontal QRS-T angle [p = 0.004 and p = 0.028, respectively]. Corrected QT, HT, and LMCA diameter were found as independent predictors of the frontal planar QRS-T angle. Subjects with HT and a larger luminal caliber of LMCA had the widest frontal planar QRS-T angle
Conclusion: Patients with a history of HT and a larger luminal caliber of LMCA had the widest frontal planar QRS-T angle. Since HT-induced electrophysiological changes are still not well established and we observed that changes in the luminal caliber of coronary arteries are associated with an abnormal frontal QRS-T angle, the frontal QRS-T angle could serve as a marker of ventricular repolarization heterogeneity in hypertensive patients in addition to keeping track of arrhythmic events, even before overt disease