Fengxiang Zhang1, Bing Yang1, Hongwu Chen1, Weizhu Ju1, Pipin Kojodjojo2, Mingfang Li1, Kai Gu1, Gang Yang1, Kejiang Cao1, Minglong Chen3. 1. Section of Pacing and Electrophysiology, Division of Cardiology, The First Affiliated Hospital with Nanjing Medical University, Nanjing, PR China. 2. National University Hospital, Singapore, Singapore. 3. Section of Pacing and Electrophysiology, Division of Cardiology, The First Affiliated Hospital with Nanjing Medical University, Nanjing, PR China chenminglong@njmu.edu.cn.
Abstract
AIMS: To identify unique electrophysiological characteristics of pulmonary artery (PA) ventricular arrhythmias (VA) and determine long-term clinical outcomes following non-contact mapping (NCM)-guided ablation. METHODS AND RESULTS: The NCM array was deployed in consecutive patients undergoing clinically indicated ablation of outflow tract (OT) VA with left bundle branch block morphology, inferior axis and the precordial lead transition zone ≥ V3. Activation, pace and NCM mapping parameters, and electrocardiogram analysis of PA VA patients were compared with 50 patients with right ventricular OT (RVOT) or aortic coronary cusps (ACC) foci. Of 170 consecutive patients, 20 (12%) patients (8 male, 39.7 ± 12.8 years old) with PA VA were identified. Electrocardiogram morphologies of PA ventricular tachycardia (VT) (located 10.8 ± 15.1 mm above the PV) were indistinguishable from RVOT VT, particularly those arising from the septal RVOT. Pulmonary artery VT can be mapped and ablated by targeting the site of earliest activation on NCM maps, with success rates of 90% after a single procedure, without anti-arrhythmics and mean follow-up of >5 years. Pace-mapping in the PA is complicated by frequent inability to capture (P < 0.01). Small far-field atrial potentials and smaller ventricular electrograms were more frequently recorded at successful sites of ablation in the PA (P < 0.05). CONCLUSION: Non-contact mapping is a useful technique to map PA VT and ablation at sites of earliest activation above the pulmonary valve is associated with excellent long-term clinical success. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: To identify unique electrophysiological characteristics of pulmonary artery (PA) ventricular arrhythmias (VA) and determine long-term clinical outcomes following non-contact mapping (NCM)-guided ablation. METHODS AND RESULTS: The NCM array was deployed in consecutive patients undergoing clinically indicated ablation of outflow tract (OT) VA with left bundle branch block morphology, inferior axis and the precordial lead transition zone ≥ V3. Activation, pace and NCM mapping parameters, and electrocardiogram analysis of PA VA patients were compared with 50 patients with right ventricular OT (RVOT) or aortic coronary cusps (ACC) foci. Of 170 consecutive patients, 20 (12%) patients (8 male, 39.7 ± 12.8 years old) with PA VA were identified. Electrocardiogram morphologies of PA ventricular tachycardia (VT) (located 10.8 ± 15.1 mm above the PV) were indistinguishable from RVOT VT, particularly those arising from the septal RVOT. Pulmonary artery VT can be mapped and ablated by targeting the site of earliest activation on NCM maps, with success rates of 90% after a single procedure, without anti-arrhythmics and mean follow-up of >5 years. Pace-mapping in the PA is complicated by frequent inability to capture (P < 0.01). Small far-field atrial potentials and smaller ventricular electrograms were more frequently recorded at successful sites of ablation in the PA (P < 0.05). CONCLUSION: Non-contact mapping is a useful technique to map PA VT and ablation at sites of earliest activation above the pulmonary valve is associated with excellent long-term clinical success. Published on behalf of the European Society of Cardiology. All rights reserved.