[Cardiac operation in patients older than 70 years]

To clarify the predictors of operative risk in the elderly, preoperative clinical features and postoperative short term outcome were retrospectively evaluated in 328 consecutive patients. Patients underwent coronary artery bypass or valvular surgery from July 1988 to December 1990 in our hospital: 78 patients were 70 years or older (elderly group) and 250 were younger than 70 years old (control group). Preoperative renal and respiratory function were slightly depressed in the elderly group than in the control group. Prolonged ventilatory support and the administration of inotropic agent were required in some elderly patients with renal or respiratory dysfunction. Neurological complications occurred more frequently in the elderly group than in the control group. Prolonged ventilatory support was needed in almost all the elderly patients with neurological complications. The operative mortality rate was similar in the two patient groups. In contrast, the hospital mortality rate was significantly higher in the elderly group than in the control group. The main causes of the higher hospital mortality in the elderly group was pulmonary infection and sepsis. These results suggest that the prolonged intensive care induces lethal infection and high hospital mortality in the elderly patients undergoing cardiac surgery.