OBJECTIVE
To analyze the immediate results of carotid endarterectomy (CEE) with selective use of temporary bypass.
MATERIAL AND METHODS
A multiple-center retrospective study included 4967 patients with internal carotid artery (ICA) stenosis between January 2005 and October 2020. All patients underwent classical carotid endarterectomy with patch repair. Depending on intraoperative bypass, all patients were divided into 3 groups: group 1 (n=1328, 26.7%) — bypass due to low retrograde blood pressure in ICA (<60% of systemic pressure); group 2 (n=1853, 37.3%) — no bypass due to satisfactory retrograde pressure (≥60% of systemic pressure); group 3 (n=1786, 35.9%) — no bypass (retrograde pressure in ICA was not measured). Mean time for installing the shunt in group 1 was 46.2±17.6 s. We describe insertion of a shunt using illustrations and discuss the main nuances of this procedure. The proposed stages of shunt placement can underlie training of residents and young vascular surgeons.
RESULTS
In-hospital incidence of lethal outcomes (p=0.62), fatal (p=0.96) and non-fatal myocardial infarctions (MI) (p=0.73), fatal stroke (p=0.54) and non-fatal stroke/transient ischemic attacks (TIA) (p=0.12) was similar. However, the largest number of «mute» stroke was recorded in patients with shunt (group 1: 2.56%, n=34; group 2: 0.5%, n=9; group 3: 0.55%, n=10; p<0.0001). This condition affected the maximum values of the combined endpoint (taking into account «mute» strokes) that was significantly higher in group 1 (group 1: 3.3%, n=44; group 2: 1.02%, n=19; group 3: 1.56%, n=28; p<0.0001). The greatest number of fatal ischemic strokes was recorded in patients with 60—80% stenosis in group 1 (p=0.02), 91—99% stenosis in group 2 (p=0.003) and group 3 (p<0.0001). The majority of non-fatal strokes (1.8%; n=5) were found in group 3 with contralateral ICA stenosis 91—99% (p=0.0008). The largest number of «mute» strokes (4.4%; n=11) was recorded in group 1 with contralateral ICA stenosis 91—99% (p=0.02). Thus, the combined endpoint showed that stroke was significantly more common in patients with contralateral ICA stenosis 91—99% (group 1: 0.4%, n=6; group 2: 0.2%, n=6; group 3: 1, 85%, n=15; p<0.0001).
CONCLUSION
Intraoperative bypass was followed by higher incidence of “mute” strokes, and the combined endpoint was more common in this group. There were no significant differences in the incidence of non-fatal/fatal stroke, TIA, MI, lethal outcomes. Measurement of retrograde pressure did not always correspond to actual compensatory possibilities of collateral circulation. As a result, significant increase in the incidence of stroke was revealed in patients with contralateral ICA stenosis 60—80% despite normal retrograde pressure. In the 3rd group, we observed higher incidence of fatal and non-fatal strokes in patients with contralateral ICA stenosis 91—99%.
