Myocardial ischaemia, infarction and cardiac-related death following carotid endarterectomy: risk assessment by thallium myocardial perfusion scan compared with clinical examination.

Risk factors in 402 patients undergoing 447 carotid endarterectomies were reviewed to see whether the presence of coronary artery disease before operation influenced the likelihood of perioperative cardiac complications. A second aim of the study was to assess whether myocardial thallium scintigraphy was valuable for preoperative assessment. Fourteen patients developed postoperative cardiac complications, six (1.3%) of which were fatal. Four of these deaths occurred in 60 patients undergoing combined carotid-coronary revascularization (6.6%). In 387 carotid endarterectomies without simultaneous coronary revascularization, there were two deaths from myocardial infarcts (0.5%). These fatalities and other cardiac complications occurred in 204 patients with preoperative clinical or ECG evidence of coronary artery disease. In 198 patients with no preoperative evidence of coronary disease there were no fatalities and only one patient with reversible postoperative myocardial ischaemia (0.4%). It is concluded that carotid endarterectomy under general anaesthesia is unlikely to be followed by cardiac complications when there is no preoperative evidence of coronary artery disease. When coronary disease is detected before operation, postoperative cardiac complications occur after 5.6% of operations, including 0.9% fatalities. When coronary artery disease is severe enough to warrant combined carotid-coronary reconstruction, the perioperative mortality rate was 6.6%, all the deaths being cardiac-related. When myocardial thallium scintigraphy was normal, postoperative cardiac complications did not occur.