Of 776 CEAs performed, 323 (42%) were considered high risk, on the basis of criteria including positive stress test (n = 109, 14%), age older than 80 years (n = 85, 11%), contralateral carotid occlusion (n = 66, 9%), pulmonary dysfunction (n = 56, 7%), high cervical lesion (n = 36, 5%), and repeat carotid operation (n = 27, 3%). Other high-risk criteria included recent
myocardial infarction (MI), cardiac surgery, or class III or IV cardiac status; left ventricular ejection fraction less than 30%; contralateral laryngeal
palsy; and previous neck irradiation (each <1.5%). Clinical presentation was similar in the high-risk and low-risk groups: asymptomatic (73% versus 73%),
transient ischemic attack (23% vs 22%), and previous
stroke (4% vs 5%). The overall postoperative
stroke rate was 1.4% (symptomatic, 2.9%; asymptomatic, 0.9%). Comparison of high-risk and low-risk CEAs demonstrated no statistical difference in the
stroke rate. Factors associated with significantly increased
stroke risk included cervical
radiation therapy, class III or IV angina, symptomatic presentation, and age 60 years or younger. Overall mortality was 0.3% (symptomatic, 0.5%; asymptomatic, 0.2%), not significantly different between the high-risk (0.6%) and low-risk groups (0.0%). Non-Q-wave MI was more frequent in the high-risk group (3.1 vs 0.9%; P <.05). A composite cluster of adverse clinical events (death,
stroke, MI) was more frequent in the symptomatic high-risk group (9.3% vs 1.6%; P <.005), but not in the asymptomatic cohort. There was a trend for more major
cranial nerve injuries in patients with local risk factors, such as high carotid bifurcation, repeat operation, and cervical
radiation therapy (4.6% vs 1.7%; P <.13). In 121 patients excluded on the basis of synchronous or immediate subsequent operations, who also would have been excluded from
SAPPHIRE, the overall rates for
stroke (1.65%; P =.69), death (1.65%; P =.09), and MI (0.83%; P =.71) were not significantly different from those in the study population.
CONCLUSIONS: