Chirurgie carotidienne - Généralités

Abstract

In cases of atherosclerotic stenosis of the internal carotid artery (ICA), the aim of surgery is to prevent stroke. The number of strokes due to carotid disease in France can be estimated 22 000 per year. These strokes can have haemodynamic causes related to low cerebral blood flow or, more often, they can be caused by embolism in relation with a morphological event of the plaque, like bleeding or ulceration. Prophylactic carotid surgery is highly recommended for symptomatic tight stenoses (70 to 99 % diameter reduction). It is justified but must be discussed according to the context for symptomatic stenoses from 50 to 69 % and for asymptomatic stenoses above 60 %. This surgery can be considered and recommended only if the stroke plus death rate of the concerned working team is below 3 % for asymptomatic stenoses, and below 5 % for symptomatic stenoses. The diagnosis is based on duplex, angiography, CT-scan and MRI. Duplex is a first-line investigation, to be done routinely, sufficient for decision making in most of the cases. Angiography is the gold standard, but due to its related risks, it is and will be done less and less. CT and MRI are still under evaluation and are likely to become gold standards; both of them allow visualisation of the stenosis and also provide an exploration of the cerebral parenchyma which is done almost systematically. Cerebral monitoring during surgery evaluates brain tolerance to ischemia during carotid clamping. There are a great number of methods but none was shown to be superior. Shunt use during cross-clamping has been largely debated, without any evidence-based indications. Nevertheless, there is a some consensus on the use of routine shunt in case of contra-lateral occlusion or surgery after recent stroke.