CATECHOLAMINE-INDUCED VENTRICULAR-TACHYCA RDIA - A CAUSE OF SUDDEN-DEATH IN TEENAGER

A 15-year-old female teenager had recurrent syncopes and had been unsu ccessfully treated for 6 years for seizures and hysteria. Syncopes wer e always triggered by emotions, or efforts, but electrocardiograms wer e normal between the episodes. A 24-hour-monitoring during a syncope, and provocative tests (exercice testing and isoprenaline administratio n) showed severe ventricular arrhythmias with premature polymorphous b eats, followed by ventricular tachycardia and then ventricular fibrill ation. These ''catecholamine-induced'' ventricular tachycardias are ve ry rare but are always fatal without treatment. Syncopes are stress-in duced and the diagnosis is almost always delayed, because the patients have a normal electrocardiogram, with normal QT interval. The arrhyth mia appears beyond a ''threshold'' sinus rate and is easily reproducib le by exercice testing. Betablockers are the only efficient treatment to prevent sudden death.