About 20% of strokes result from narrowing of the carotid artery (the main artery supplying blood to the brain). Carotid endarterectomy is an operation that involves opening the carotid artery to remove this narrowing and therefore reduce the risk of stroke. However, there is a 5% to 10% risk of the operation itself causing a stroke. There is evidence that, at the end of the operation when the artery is being closed, inserting a patch into the gap in the artery reduces the risk of strokes. Patches are made out of either synthetic material or the patient's own vein. This review aimed to assess whether one type of patch was better than another; however, the 13 trials reviewed did not provide clear evidence about which type of patch material is best. Vein patches may rupture with potentially fatal consequences and synthetic materials are vulnerable to infection. Further research is needed.
The number of outcome events is too small to allow reliable conclusions to be drawn and more trial data are required to establish whether any differences do exist. Nevertheless, there is some evidence that other synthetic (e.g. PTFE) patches may be superior to collagen impregnated Dacron grafts in terms of perioperative stroke rates and restenosis. Pseudoaneurysm formation may be more common after use of a vein patch compared with a synthetic patch.
Carotid patches for carotid endarterectomy may be made from an autologous vein or synthetic material.
To assess the safety and efficacy of different materials for carotid patch angioplasty.
We searched the Cochrane Stroke Group trials register (last searched 3 August 2009), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2009), MEDLINE (1966 to November 2008), EMBASE (1980 to November 2008) and Index to Scientific and Technical Proceedings (1980 to 2008). We handsearched relevant journals and conference proceedings, checked reference lists, and contacted experts in the field.
Randomised and quasi-randomised trials comparing one type of carotid patch with another for carotid endarterectomy.
Two review authors independently assessed eligibility, trial quality, and extracted data.
We included 13 trials involving a total of 2083 operations; seven trials compared vein closure with PTFE closure, and six compared Dacron grafts with other synthetic materials. In most trials a patient could be randomised twice and have each carotid artery randomised to different treatment groups. There were no significant differences in the outcomes between vein patches and synthetic materials apart from pseudoaneurysms where there were fewer associated with synthetic patches than vein patches (odds ratio (OR) 0.09, 95% confidence interval (CI) 0.02 to 0.49). However, the numbers involved were small and the clinical significance of this finding is uncertain. Compared to other synthetic patches, Dacron was associated with a higher risk of: perioperative combined stroke and transient ischaemic attack (P = 0.03); restenosis at 30 days (P = 0.004); perioperative stroke (P = 0.07) and perioperative carotid thrombosis (P = 0.1). During follow-up for more than one year, there were also significantly more strokes (P = 0.03), stroke/death (P = 0.02) and arterial restenoses (P < 0.0001) with Dacron but the numbers of outcomes were small and the significance of this finding is uncertain.