Reentrant Ventricular Tachycardia Originating in the Right Ventricular Outflow Tract Slow Conduction Identified by Right Coronary Artery Ostium Pacing

Abstract

n general, ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) is not associated with organic heart disease. The origin of RVOT tachycardia is almost in the anterior septum of the right ventricle. 1,2 The mechanism is mainly due to triggered activity and it is rare for there to be a reentry. A case of 2 types of reentrant VT originating from RVOT induced by electrophysiological study (EPS) in a patient with mitral regurgitation, atrial fibrillation with complete atrioventricular block and pacemaker implantation is reported. The exit of the VT reentry circuit and slow conduction zone were examined using an entrainment mapping technique and a pace mapping technique. Case ReportA 72-year-old woman with a history of mitral regurgitaCirculation Journal Vol.72, May 2008 tion, hypertension, atrial fibrillation, complete atrioventricular block and pacemaker implantation was admitted to hospital for treatment of symptomatic VT, which was recorded by Holter electrocardiogram (ECG) monitoring, and complaining of edema in the legs and dyspnea. An ECG recorded during atrial fibrillation showed a right ventricular (RV) pacing rhythm of 80 beats/min, and a chest X-ray revealed cardiac enlargement (59.9%) with slight lung congestion. Echocardiography revealed the following: decreased left ventricular (LV) wall motion, especially in the anterior septum; LV diastole/systole of 50/43 mm; ejection fraction of 36%; aorta/left atrial size of 29/55 mm; ventricular septum/posterior wall of 12/11 mm; and mitral and tricuspid regurgitation levels of IV and II, respectively (27.5 mmHg).Coronary angiography (CAG) revealed no significant stenosis. Symptoms were improved with diuretics and PDE III inhibitors after admission. A monitoring ECG recorded VT that lasted for 1 min, and this was considered to be the contributing cause of palpitation. EPS and Radiofrequency Catheter Ablation: First SessionAfter written informed consent was obtained from the patient and her family to undertake all procedures associated with this study, a standard EPS, endocardial catheter mapping and radiofrequency catheter ablation were performed. Electrode catheters were inserted percutaneously into the femoral vein and positioned in the RV apex, outflow and His bundle position. Ventricular mapping and radiofrequen- A case of reentrant ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) is described. An electrophysiological study revealed that programmed stimulation from the right ventricle apex induced 2 types of VT with similar left bundle branch block configuration and inferior axis. Yet, VT cycle length (CL) was different; one was stable, sustained VT with a CL of 360 ms and the other was hemodynamically intolerable VT with a CL of 330 ms. Similarly for both VTs, perfect pace mapping was obtained at the anterior septum beneath the pulmonary valve in the RVOT, and exits of both VTs were very close. Entrainment mapping during stable VT was performed and the anterior septum RVOT was desig...

A phenomenological model for the X-ray spectrum of nova V2491 Cygni

“…Nova V2491 Cyg was discovered on April 10, 2008, at V = 7.7 (Nakano et al 2008). The optical flux declined from this peak in the course of the following months, interrupted by a brief second maximum at the end of April.…”

Novel ECG Predictor of Difficult Cases of Outflow Tract Ventricular Tachycardia: Peak Deflection Index on an Inferior Lead

“…adiofrequency catheter ablation (RFCA) is a safe and effective treatment for outflow tract ventricular tachycardia/ventricular premature contractions (OT-VT/VPC), [1][2][3][4] but in some patients the OT-VT was not able to be treated by ablation from the ventricular endocardium or coronary cusps. 5,6 If an ECG parameter could predict spontaneous ventricular tachyarrhythmia, 7 it would be useful.…”

Identification of Unusual Reentry Circuit Sites of Nonischemic Ventricular Outflow Tract Tachycardia

“…Ablation terminated the VT and the VT became uninducible with repeat-programmed stimulation. 13 In patient 5 ( Figs. 4 and 5), scar tissue was delineated by voltage mapping using CARTO, and entrainment mapping was used to determine the VT circuit.…”

“…There, we determined a site in the anteroseptal wall to be an exit site. Ablation terminated the VT and the VT became uninducible with repeat‐programmed stimulation 13 …”