[Prinzmetal's syncopal angina during an electroencephalogram. Triggering role of the hyperpnea test].

We are reporting a cardiac arrest occurring during an electroencephalogram with hyperventilation. The diagnosis is made on the Holter recording which shows a Prinzmetal's angor tracing followed with ventricular arrhythmias, leading to asystoly. The physiopathology of the spasm is not clear and we are discussing the possible mechanisms. We stress again the harmful role of beta-blockers in this pathology. In addition, we insist on electrocardiographic manifestations surrounding sudden death. As for the hyperventilation test, its potential risks call for caution during its performance.