Yosuke Murakami

Radiofrequency catheter ablation of idiopathic left anterior fascicular ventricular tachycardia in children

BACKGROUND Idiopathic ventricular tachycardia of left anterior fascicular origin (IVT-LAF) is a rare condition, and radiofrequency catheter ablation (RFCA) therapy has not been reported in children. OBJECTIVE This study aimed to evaluate the procedures and outcomes of RFCA for pediatric IVT-LAF. METHODS Pediatric IVT-LAF cases for which RFCA was performed between June 2006 and May 2012 at our hospital were reviewed. RESULTS Of 537 pediatric cases of RFCA, 6 had IVT-LAF; 4 had anterior fascicular involvement only, while 2 had both anterior and posterior fascicular involvement. All 6 of them underwent RFCA at the median age of 8.8 years (range 4.3-14.3 years). RFCA was successful in all patients, but 4 had recurrence and underwent 1-3 additional sessions of RFCA. In a total of 10 RFCA sessions, the overall recurrence rate was 50%. The site of RFCA was determined on the basis of detection of diastolic potential during ventricular tachycardia (7 sessions) or isolated delayed potential during sinus rhythm (1) or by pace mapping (2). During the median follow-up period of 33 months, no further recurrence was reported except for 1 patient, who had a recurrence and was scheduled for additional session at the time of this report. Major complications included 1 case of complete atrioventricular block and 1 case of complete left bundle branch block. CONCLUSION Despite a high recurrence rate and a few complications, RFCA of the site of isolated delayed potential or diastolic potential, if applied cautiously, is a possible treatment of choice for pediatric IVT-LAF.

Novel Technique for Implantation of a Cardioverter Defibrillator in Children

An 8-year-old boy with hypertrophic nonobstructive cardiomyopathy with ventricular fibrillation underwent implantation of an implantable cardioverter defibrillator. The lead was inserted through a pursestring suture in the right atrial appendage, and the tip of coil was placed in the right ventricular apex under fluoroscopic guidance. Another defibrillation coil was placed in the back of the left atrium and left ventricle by the transverse sinus. The device wrapped in a monofilament mesh sheet was placed in the intraperitoneal space. This case utilized a new technique for an implantable cardioverter defibrillator implantation in a small child.

Three Cases of KCNT1 Mutations: Malignant Migrating Partial Seizures in Infancy with Massive Systemic to Pulmonary Collateral Arteries

KCNT1 mutations are gain-of-function mutations in potassium channels resulting in severe infantile epilepsy. Herein we describe 3 infants with malignant migrating partial seizures with KCNT1 mutations accompanied by massive systemic to pulmonary collateral arteries with life-threatening hemoptysis and heart failure.

Ectopic Atrial Tachycardia Originating from Right Atrial Appendage Aneurysms in Children: Three Case Reports

Introduction Ectopic atrial tachycardia occurs at a rate of 5%–20% among children with supraventricular tachycardia. Atrial appendages are the most frequent focus in children, differing from the situation in adults. However, ectopic atrial tachycardia originating from aneurysms of the right atrial appendage is very rare and in fact has not yet been clearly defined. We describe 3 cases of children with ectopic atrial tachycardia resulting from right atrial appendage aneurysms that proved refractory to radiofrequency catheter ablation. All 3 children were treated surgically. Written consent from the legal guardians of the patients was received for publication of the details of these cases.