Dual antiplatelet therapy prior to carotid endarterectomy reduces post-operative embolisation and thromboembolic events: post-operative transcranial Doppler monitoring is now unnecessary

Abstract

Background: Thrombotic stroke following carotid endarterectomy (CEA) is preceded by high-grade embolisation (detected using transcranial Doppler (TCD)) and can be prevented by incremental doses of Dextran. However, this strategy is labour intensive and Dextran manufacture has now ceased. A randomised trial has suggested that a single 75 mg dose of Clopidogrel (administered the night before surgery in addition to daily 75 mg Aspirin) significantly reduces post-CEA embolisation. We hypothesized that this model of dual antiplatelet therapy might significantly reduce the need for adjuvant Dextran therapy.

Methods: Retrospective audit of prospectively acquired data in 297 patients undergoing CEA between 01.08.2006 and 30.07.2009. All received routine Aspirin (75 mg daily) in addition to a single 75 mg dose of Clopidogrel the night before surgery. All underwent completion angioscopy and those with a temporal window (n = 270) underwent intra- and post-operative TCD monitoring.

Results: High rate embolisation requiring Dextran (>25 emboli in any 10 min period) occurred in only 1/270 patients (0.4%), significantly less than the 3.2% rate in historical controls where Clopidogrel was not administered. There were no peri-operative deaths, but 3/297 patients suffered non-disabling strokes (intra-operative extension of a pre-existing deficit, haemorrhage into lentiform nucleus after hypertensive crisis, contralateral embolic stroke). The overall 30-day death/stroke rate (1.0%) was not-significantly lower than the 2.6% rate observed in the preceding 821 patients.

Conclusions: 75 mg Clopidogrel administered the night before surgery (in addition to daily 75 mg Aspirin) was associated with a significant reduction in post-operative embolisation and Dextran utilisation. No ipsilateral thromboembolic ischaemic events occurred in this series. As a consequence of this audit, one dose of 75 mg Clopidogrel will continue to be given pre-operatively (in addition to daily 75 mg Aspirin) and routine post-operative TCD monitoring has now ceased.