CEREBRAL COMPLICATIONS AFTER CORONARY-ARTERY BYPASS AND HEART-VALVE SURGERY - RISK-FACTORS AND ONSET OF SYMPTOMS

Objectives: Cerebral complications continue to be a major cause of mor bidity after cardiac surgery. Earlier studies have mainly focused on i ntraoperative events, but symptoms may also occur later in the postope rative period. The purpose of this study was to determine the incidenc e and risk factors of focal neurologic complications and timing of cer ebral symptoms. Design: A retrospective study. Setting: Linkoping Univ ersity Hospital. Participants: Two thousand four hundred eighty patien ts who underwent cardiac surgery from 1992 to 1995. Interventions: Sta ndard cardiopulmonary bypass (CPB) technique was used in all patients. Anticoagulant treatment included heparin and patients with coronary a rtery surgery were also administered acetylsalicylic acid and valve-su rgery patients received warfarin or dicumarol. Measurements and Main R esults: Seventy-five patients (3%) had focal neurologic deficits and/o r confusion postoperatively. In 32 patients (43%), the onset was not i ntraoperative but occurred later in the postoperative period. The lowe st incidence of cerebral complications was found in patients who under went single-valve replacement (1.2%) and the highest incidence was fou nd in patients who underwent combined procedures (valve and coronary a rtery surgery; 7.6%). Patients greater than 70 years of age had a comp lication rate of 4.1% compared with 2.5% in patients aged 70 years and less (p < 0.05). The incidence of diabetes mellitus was 11.4% in the entire series, but was more common (18.7%; p < 0.05) in patients with cerebral symptoms. Also, 5.9% of all patients had a history of cerebro vascular disease compared with 14.7% (p < 0.01) of patients with cereb ral complications. Conclusion: Cerebral complications may be delayed a fter cardiac surgery, suggesting causes of cerebral damage other than intraoperative events. Valve-surgery patients had the lowest incidence and patients with combined procedures had the highest incidence of ce rebral complications. Advanced age, diabetes mellitus, and preexisting cerebrovascular disease increased the risk. Copyrights 1998 by W.B. S aunders Company.