Electrocardiographic characteristics of idiopathic ventricular arrhythmias originating from the tricuspid annulus regions

Abstract

Object: To explore the electrocardiographic characteristics of ventricular arrhythmias (VAs) originating from tricuspid annulus region. Methods: Present study included 169 consecutive patients undergoing catheter ablation of VAs from tricuspid annulus origin in our department from August 2007 to September 2016. Based on the origin sites, the patients were divided into two subgroups, the free wall group (81 cases) and septal wall group (88 cases). Based on the location, patients in the free wall group were classified into anterolateral (22 cases), lateral (26 cases) and posterolateral (33 cases) subgroups. Patients in the septal group were classified into anteroseptal (10 cases), midseptal (71 cases) and posteroseptal (7 cases) subgroups. We analyzed the electrocardiographic features of these patients and in 87 patients with PVCs/VT originating from right ventricular outflow tract. Results: (1) A positive R wave inⅠ, aVL, V(5)-V(6) leads were found among most of patients, only few cases originating from tricuspid annulus anteroseptum group and tricuspid annulus anterolateral group demonstrated qr or qs pattern in aVL lead. 97.53% (79/81) patients demonstrated rS pattern in V(1)-V(3) leads with VAs originating from tricuspid annulus free wall, and 9/10 patients demonstrated rS pattern in V(1) lead with VAs originating from anteroseptum, and 97.44% (76/78) patients demonstrated QS pattern in V(1) lead with VAs originating from midseptum and posteroseptum. Precordial lead transition zone was on or behind V(3) for tricuspid annulus free wall group (96.3%, 78/81), but in front of V(3) for tricuspid annulus septum wall group (47.73%, 42/88) (P<0.01). The S wave's amplitude smaller than-1.81 mV in lead V(2) can be used as a cutoff value to identify if PVC/VT is originating from free wall or septum of TA. R wave in inferior wall leads was found among 98.85% (86/87) patients with PVCs/VT originating from right ventricular outflow tract. Conclusion: A positive R wave in Ⅰ, aVL, V(5)-V(6) leads was found among most of patients with idiopathic ventricular arrhythmias originating from the tricuspid annulus regions, but VAs originating from different portions of tricuspid annulus area have distinct electrocardiographic characteristics.