The effects of premature ventricular complex ablation on cardiac repolarization; evaluation of changes in the frontal QRS-T angle

Abstract Aims and Goals Premature ventricular complex (PVC) is one of the most common arrhythmias in the general population, and may cause cardiomyopathy in some individuals. Although this condition, called PVC induced cardiomyopathy, does not develop in every individual; current literature on which individuals are susceptible to develop this condition is limited. Frontal QRS-T angle is a marker of cardiac repolarization heterogeneity. Studies have found that impaired frontal QRS-T angle is associated with arrhythmias and sudden cardiac death. To our knowledge, there is no study in the current literature on the effects of the transcatheter radiofrequency ablation of the PVCs on the frontal QRS-T angle. For this reason, we aimed to investigate the frontal QRS-T angle changes that occur after PVC ablation in our study. Materials and Methods 48 patients (24 male and 24 female) who underwent PVC ablation in 3 centers were included in our study by retrospectively. Patients with atrial fibrillation, left or right bundle branch block, or pacemaker rhythm were not included in the study. Levels of complete blood count, serum electrolytes, kidney function tests, fasting lipid panels, and reports of 24-hour rhythm holter records, transthoracic echocardiography and PVC ablation procedures were obtained from the hospital systems. Standard 12-lead electrocardiograms of all patients recorded before and after ablation were scanned from the system. Frontal QRS-T angles during basal sinus rhythm were calculated and frontal QRS-T angles before and after the procedure were recorded. Results The frontal QRS-T angle was found to be abnormal before ablation in 6 of the 48 patients, and normal in the remaining 42 patients. After the ablation, the frontal QRS-T angle returned to normal limits in 6 of the 6 patients with abnormal frontal QRS-T angles (p < 0.001), and the frontal QRS-T angles of 42 patients with normal frontal QRS-T angles before the ablation continued to remain within normal limits after the ablation (p < 0.001) The daily PVC rate was found to be an average of 31.2% in patients with an abnormal [f(QRS-T)] angle and 21.5% in patients with a normal [f(QRS-T)] angle (p < 0.05). No statistically significant correlation was detected in the analyzes of other findings. Conclusion PVC ablation did not cause deterioration in the frontal QRS-T angle in patients with normal frontal QRS-T angle. In patients with abnormal frontal QRS-T angle, the frontal QRS-T angle returned to normal limits after PVC ablation. It was determined that the deterioration in the frontal QRS-T angle evaluated before the ablation procedure was correlated with the daily number of PVCs. We believe that prospective studies with a larger patient group are needed to investigate how the frontal QRS-T angle is affected by PVCs and the effects of PVC ablation on the development of cardiomyopathy in these patients.