Successful catheter ablation of idiopathic premature ventricular contractions originating from the "right" ventricular outflow tract in a patient with dextrocardia and situs inversus viscerum.

Article history: Received 17 June 2015 Accepted 26 June 2015 Available online 2 July 2015 radiofrequency ablation with rare complications. However, after a review of the medical literature, and to our knowledge, there has been only one case report of catheter ablation of PVC in patients with dextrocardia and situs inversus published. What's more, this is the first case of successful idiopathic “R”VOT-PVC ablation using a three-dimensional mapping system in an adult with dextrocardia and situs inversus viscerum. While the initial case of “R”VOT-PVC ablation in dextrocardia was reported by Bonnemeier et al. last A 65-year-old man was referred for catheter ablation of idiopathic premature ventricular contractions (PVC) because of severe palpitations for more than one year. No abnormality except for right-sided heart sounds was found in the physical examination and laboratory tests, which indicated likely dextrocardia. The chest radiogram and CT further confirmed it and abdominal ultrasound found situs inversus viscerum as well. Electrocardiogram indicated right axis deviation with an inversion of the electrical waves in I, aVR and aVL, as well as sustained ventricular bigeminy. The monomorphic PVC had left bundle branch block (LBBB) with inferior axis after V1–V6 inversed and positioned over the right chest (Fig. 1A). Transthoracic echocardiography revealed a normal “left” ventricular ejection fraction (LVEF 60%) without structural abnormality. The St. Jude Ensite 3000 mapping system was used to make a detailed electroanatomic map of his “right” ventricle. Activation mapping revealed the earliest site of ventricular activation 40 msec earlier than the QRS complex on surface electrocardiogram, which existed in the posterior septum of the “right” ventricular outflow tract (RVOT) (Fig. 2A). Pace mapping at this site showed a 12-lead match between paced beats and arrhythmia complexes. Radiofrequency ablation at this site resulted in PVC termination successfully (Fig. 2B–C) and no PVC could be induced by ventricular stimulation during the subsequent 30 min after the procedure, as well as for the rest of the hospital stay. There was no recurrence of PVC in subsequent 3 month follow-up according to the results of a 24 h-Holter.