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Spontaneous Episode of Polymorphic Ventricular Tachycardia in a Patient with Intermittent Brugada Syndrome

A 54-year-old patient presented with aborted sudden cardiac death and documented ventricular  brillation. On admission, there were no signi cant abnormalities on 12lead ECG. Extensive diagnostic work-up (echocardiography, right and left heart catheterization, and coronary angiography) did not show structural heart disease. During ECG telemetry monitoring (lead I represents a bipolar precordial lead), a spontaneous episode of polymorphic ventricular tachycardia (VT) occurred. Before the episode started, gradual changes in the terminal QRS complex and ST segment were seen. Directly before the short runs of nonsustained VT, right bundle branch block-like changes and downsloping ST segment elevation were seen. The QT interval remained normal. After a longer episode of polymorphic VT terminated spontaneously, the signi cant changes in ST segment reverted. This sequence of events suggests a causal relationship between the changes in cardiac repolarization and development of the arrhythmia. Pharmacologic challenge with ajmaline 25 mg revealed right bundle branch block-like changes and downsloping ST segment changes in leads V1 to V3. During electrophysiologic testing, polymorphic VT was inducible with two extrastimuli, and an automatic de brillator was implanted. After ICD placement, the patient experienced three appropriate shocks for rapid VT. All episodes were terminated successfully by the device. J Cardiovasc Electrophysiol, Vol. 12, p. 1094, September 2001.