OBJECTIVE--To determine the incidence and outcome of refractory cardiac arrest necessitating emergency coronary artery bypass grafting. DESIGN--Retrospective survey of cardiac catheterisation and surgical records. SETTING--The London Chest Hospital. PATIENTS--All patients requiring emergency coronary artery bypass grafting after cardiovascular collapse in the catheterisation suite between January 1984 and December 1989. MAIN OUTCOME MEASURES--Incidence of refractory cardiac arrest in the study group and perioperative mortality. RESULTS--Thirteen of 8675 patients undergoing coronary arteriography or angioplasty had refractory cardiac arrests. Five patients died, but the remainder survived to be discharged from hospital without serious morbidity. CONCLUSION--Without immediate surgical intervention the mortality for these 13 patients would have been 100%.