Surgery for asymptomatic carotid stenosis: a study of three patient subgroups

The purpose of this retrospective study was to determine whether patients who undergo prophylactic surgery for asymptomatic carotid stenosis represent a single homogeneous population. Of the 805 carotid reconstructions performed between January 1984 and December 1992, a total of 357 were for asymptomatic atherosclerotic stenosis in 312 patients (227 men, 85 women) with a mean age of 69.6 years. Patients were divided into three groups. Group I included 141 patients (161 procedures) who presented no neurologic manifestations. Group II included 49 patients (55 procedures) who underwent carotid reconstruction before or at the same time as another cardiovascular procedure. Group III included 122 patients (141 procedures) who presented nonhemispheric manifestations. Patients in group III had a significantly higher number of obstructive lesions in brain arteries (p < 0.01). Seven patients died within the first 30 postoperative days, including three who underwent combined single-stage procedures. Nine patients presented nonfatal stroke, including three who progressively recovered. The cumulative death-stroke rate (CDSR) was 5.12% overall, 3.54% in group I, 12.24% in group II, and 4.09% in group III. The difference between groups I and II was statistically significant (p < 0.05). Taking into account only deaths related to carotid surgery and stroke with permanent disability, the CDSR was 2. 83% in group I and 3.25% in group III. Follow-up ranged from 24 to 132 months (mean: 66.2) with a total of 11 patients being lost from follow-up. Actuarial 5-year survival was 81.99 +/- 7.13% in group I, 70.65 +/- 13.72% in group II, and 68.51 +/- 8.93% in group III. Differences between group I and both groups II (p < 0.01) and III (p < 0.05) were statistically significant. Overall 5-year patency was 95.59 +/- 2.28%. Stroke occurred during follow-up in 13 patients. The probability of stroke-free survival was 95.29 +/- 3.76% in group I, 91.03 +/- 8.52% in group II, and 89.09 +/- 6.39% in group III. The difference between groups I and III was statistically significant (p < 0.05). Patients with asymptomatic carotid lesions can be divided into different prognostic groups. Life expectancy is shorter for patients with multiple artery disease. Long-term stroke risk is higher in patients with nonhemispheric neurological manifestations.