To investigate the relationships between limitation of physical activity and dyspnoea and chest pain before and 2 years after coronary artery bypass grafting (CABG) and preoperative left ventricular ejection fraction (LVEF), questionnaires were issued to all patients from Western Sweden who underwent CABG during 1988-1991. The analysis comprised 985 patients. Physical activity improved significantly after CABG regardless of the preoperative LVEF. No significant association was found between LVEF and degree of limitation of physical activity before or after surgery. Dyspnoea and chest pain improved markedly, irrespective of LVEF. There was significant association between freedom from dyspnoea and LVEF preoperatively (less dyspnoea with higher LVEF), but not after CABG. The frequency of chest-pain attacks was not related to LVEF, before or after the operation. Thus physical activity, dyspnoea and chest pain improved in the 2 years after CABG irrespective of preoperative LVEF. Absence of dyspnoea was related to LVEF before, but not after surgery, and there was no association between preoperative LVEF and frequency of anginal attacks before or after CABG.