Israel Medical Association Journal

Background: Idiopathic left ventricular tachycardia with a right bundle branch block configuration and left axis deviation, first described by Belhassen et al., is a rare electrocardiographic-electrophysiologic entity. Radiofrequency catheter ablation has been proposed as a good therapeutic option, but the best criteria for determining the optimal site of ablation are still under debate.

Objectives: To report the clinical features, electrophysiologic characteristics, results of RFA[1], and long-term outcome in 18 patients with "Belhassen's VT” treated in our laboratory during the last 10 years, stressing the best electrophysiologic criteria for determining the optimal site of ablation.

Methods: Eighteen consecutive patients with this specific VT[2] underwent RFA in our laboratory during the last 10 years. RFA was acutely successful in 17 patients after one or two procedures (15 and 2 patients, respectively) using 4.1 ± 2.2 RF pulses. The putative ablation sites were defined by good pace-mapping (3 patients), earliest recorded Purkinje spike prior to the QRS onset during VT or sinus rhythm (6 patients), earliest endocardial activation during VT (1 patient), and diastolic potential preceding the Purkinje spike during VT and/or late diastolic potential in sinus rhythm (7 patients). In the patients with a definite successful ablation, the ratio of successful to unsuccessful radiofrequency pulse delivery to the diastolic potential site was compared to that of other methods. The ratio of successful RFA at the diastolic potential site (5:8) was higher than in the other methods (8:31), and the difference was statistically significant (P = 0.05). Successful ablation sites were more basal when the diastolic potential site was chosen.

Conclusion: The results of the present study confirm the high success rate and safety of RFA using conventional techniques in the management of “Belhassen VT,” suggesting that this procedure can be proposed as a first-line therapy. Ablating at a site demonstrating a late diastolic potential is at least as effective as ablating at a ventricular exit site, although the use of combined electrophysiologic criteria may be the optimal approach.

Background: Long-term follow-up in apical hypertrophic cardiomyopathy is rare.

Objective: To study the natural history of the disease.

Methods: We followed 11 patients, 5 women and 6 men, for 5-20 years.

Results: At presentation all 11 patients had typical features of apical hypertrophic cardiomyopathy, with dyspnea in 3 and chest pains in 8, of whom 5 were typical of angina and 3 had myocardial infarction. R-wave voltage and T-wave negativity progressively decreased in magnitude at serial electrocardiograms in four patients. Perfusion defects were detected on thallium myocardial scintigraphy in three, increased apical uptake in two, and normal in one patient. Apical aneurysm with normal coronary arteries developed in a patient who had sustained ventricular tachycardia. All of the 10 catheterized patients had normal coronaries except for one with significant left anterior descending artery stenosis and another with a minor lesion. Symptomatic sustained ventricular tachycardia was found in two patients, one of whom required the implantation of an internal cardioverter-defibrillator.

Conclusions: Apical hypertrophic cardiomyopathy may develop morphologic and electrocardiographic changes with life-threatening arrhythmias necessitating close follow-up and treatment.