ELECTROPHYSIOLOGIC STUDY OF THE LEFT-VENTRICLE - INDICATIONS AND SAFETY

Patients (69 with documented or suspected recurrent ventricular tachycardia or fibrillation, 10 with left bundle-branch block and 1 with Wolff-Parkinson-White syndrome) underwent right ventricular and left ventricular programmed electrical stimulation, including ventricular pacing and introduction of 1 or 2 ventricular extrastimuli and or electrode catheter mapping of the left ventricle. Left ventricular catheters were introduced percutaneously via the femoral artery (of 61 patients, 1 required secondary repair) or via brachial arteriotomy (of 19 patients, 2 required secondary repair). All patients received heparin i.v. (5000 units) following insertion of the left ventricular catheter and then 1000 units/h after 1st h of study. No patients had cerebrovascular, systemic thromboembolic or cardiac sequelae. In 4 (12%) of 34 patients with inducible ventricular tachycardia, programmed electrical stimulation of the left ventricle was required for initiation. Extensive left ventricular endocardial mapping was performed in 45 patients. Electrophysiologic study of the left ventricle can be performed safely. Programmed electrical stimulation of the left ventricle is indicated when a suspected ventricular tachyarrhythmia cannot be induced from the right ventricle. Endocardial mapping of the left ventricle is indicated when surgery to abolish recurrent sustained ventricular tachycardia is considered.