A 47-year-old man was referred by an emergency physician to the intensive care unit of a hospital under resuscitation conditions while having recurrent attacks of ventricular fibrillation. Coronary angiography, performed while resuscitation measures had to be maintained, revealed severe three-vessel disease with occlusion of the anterior interventricular branch at its origin. Electrical and haemodynamic instability persisted even after thrombolysis with urokinase and introduction of an intraaortic balloon pump. Percutaneous partial cardiopulmonary bypass (CPB) was, therefore, instituted and a cardiac output of 2.5 1 achieved together with a stable sinus rhythm and a systolic pressure of 60-80 mm Hg. After 9 h on CPB, drug administration could be levelled off and he was mobilised. He showed no neurological deficits and 4 months later he underwent an elective coronary bypass operation. This report demonstrates that even in conditions of resuscitation mechanical circulatory support can be undertaken rapidly and successfully, in the face of electrical instability, to achieve at least temporarily a stable circulation.