Objectives: It is a big challenge to manage noninducible ventricular tachycardia (VT) during attempted radiofrequency ablation procedure. In this report we describe successful elimination of noninducible VT by identif...Objectives: It is a big challenge to manage noninducible ventricular tachycardia (VT) during attempted radiofrequency ablation procedure. In this report we describe successful elimination of noninducible VT by identifying the arrhythmia substrate using electroanatomic mapping system. Methods and Results: A 38-year-old man was admitted for arrhythmia management due to 7 years’ recurrent paroxysmal palpitations that were not related to exercise or emotional stress. A 200 beat per minute VT was documented clinically during the spell of palpitation and it could be terminated by intravenous infusion of verapamil. The QRS morphology of VT indicating a left anterior fascicle origin, rS in leads I and aVL, qR in II, III and aVF, rsR in V1 and rS in V6 with a right axis in the frontal plane (140). Structural heart disease was not established by physical examination, transthoracic echocardiography, chest X ray and magnetic resonance imaging. During the attempted ablation procedure, however, VT could not be induced both from atrium and ventricle, even with the challenge of isoproterenol. The left anterior and posterior fascicles were localized during sinus rhythm using the electroanatomic mapping system (CARTO). A linear line was created with 5 sequential radiofrequency lesions across the medial part of left anterior fascicle guided by the electroanatomic mapping system. After ablation, the depth of the S wave in leads I and aVF was significantly decreased, so was the amplitude of the R wave in lead III. Eight months later, the patient is free from recurrences of VT despite difficult arrhythmia control preprocedure. Conclusions: Idiopathic left VT has been shown to be due to reentry anchored in left posterior or anterior fascicles and the Purkinje system. The most prevalent form verapamil-sensitive intrafascicular tachycardia characterized by right bundle branch block and left axis morphology originates in the region of left posterior fascicle of the left bundle. Idiopathic VT characterized by right bundle branch block and right axis deviation originating in the left anterior fascicle is rare. Earlier studies have shown that successful ablation of idiopathic left ventricular tachycardia could be achieved at sites proximal to the tachycardia exit site. The findings of this case report demonstrated that noninducible idiopathic VT could be successfully suppressed by identifying the reentry circuit using electroanatomic mapping system.展开更多
文摘Objectives: It is a big challenge to manage noninducible ventricular tachycardia (VT) during attempted radiofrequency ablation procedure. In this report we describe successful elimination of noninducible VT by identifying the arrhythmia substrate using electroanatomic mapping system. Methods and Results: A 38-year-old man was admitted for arrhythmia management due to 7 years’ recurrent paroxysmal palpitations that were not related to exercise or emotional stress. A 200 beat per minute VT was documented clinically during the spell of palpitation and it could be terminated by intravenous infusion of verapamil. The QRS morphology of VT indicating a left anterior fascicle origin, rS in leads I and aVL, qR in II, III and aVF, rsR in V1 and rS in V6 with a right axis in the frontal plane (140). Structural heart disease was not established by physical examination, transthoracic echocardiography, chest X ray and magnetic resonance imaging. During the attempted ablation procedure, however, VT could not be induced both from atrium and ventricle, even with the challenge of isoproterenol. The left anterior and posterior fascicles were localized during sinus rhythm using the electroanatomic mapping system (CARTO). A linear line was created with 5 sequential radiofrequency lesions across the medial part of left anterior fascicle guided by the electroanatomic mapping system. After ablation, the depth of the S wave in leads I and aVF was significantly decreased, so was the amplitude of the R wave in lead III. Eight months later, the patient is free from recurrences of VT despite difficult arrhythmia control preprocedure. Conclusions: Idiopathic left VT has been shown to be due to reentry anchored in left posterior or anterior fascicles and the Purkinje system. The most prevalent form verapamil-sensitive intrafascicular tachycardia characterized by right bundle branch block and left axis morphology originates in the region of left posterior fascicle of the left bundle. Idiopathic VT characterized by right bundle branch block and right axis deviation originating in the left anterior fascicle is rare. Earlier studies have shown that successful ablation of idiopathic left ventricular tachycardia could be achieved at sites proximal to the tachycardia exit site. The findings of this case report demonstrated that noninducible idiopathic VT could be successfully suppressed by identifying the reentry circuit using electroanatomic mapping system.
