Carotid artery patient selection

Clinical trials and meta-analyses have demonstrated that early carotid endarterectomy (CEA) is the preferred treatment for most patients with severe symptomatic internal carotid artery (ICA) stenosis and selected patients with moderate disease.However, CEA is often delayed in chnical practice, or may not be appropriate in some patients due to an unfavorable risk-benefit profile. In these settings, it is reasonable to consider acute antithrombotic treatment to prevent early recurrent stroke. 

The surgical removal of atheromatous plaque from within the carotid artery is termed carotid endarterectomy. The operation was first performed in an attempt to improve the flow of blood to the brain, although no systematic attempt was made to assess the risks and benefits of the procedure. Subsequently, randomized trials were performed in patients with a history of recent symptomatic stroke, and also in those with asymptomatic disease, to determine whether the operation was beneficial and, if so, what the predictors of benefit would be. As a result of these trials, carotid endarterectomy has been proven to be an effective treatment for the secondary prevention of stroke in selected patients. 

Fig. 5.49. a,b Conventional angiography, ap and lateral view, of the internal carotid artery CCF due to a ruptured cavernous aneurysm before (c) and after (d) selective treatment of the aneurysm in a patient with acute ophthalmoplegia... 

Atherosclerotic vascular disease is more frequent in elderly patients and may be associated with more tortuous vessel anatomy. Superselective catheterizations of distal cerebral vessels might thus become technically more difficult. Atherosclerotic carotid bifurcation disease is frequently associated in patients with advanced age and might increase the risk of thromboembolic complications. In selected cases, a combined approach, first stenting of the carotid artery stenosis and subsequently coil embolization of the ruptured aneurysm might be a therapeutic option. 

Thus, there are a number of potential mechanisms by which PUFA are anti-atherosclerotic. However, in a group of selected patients with documented CAD, (0-3 PUFA, given for 2 years did not demonstrate an effect on slowing the progression of atherosclerosis of the carotid arteries as measured by ultrasound (93). 

A similar trade-off between diagnostic accuracy and risk is necessary when imaging the carotid bifurcation in patients with TIA or ischemic stroke. Performing intra-arterial catheter angiography in everyone is clearly unacceptable because of the risks and cost. Fewer than 20% of patients will have an operable carotid stenosis even if only those with cortical rather than lacunar events are selected (Hankey and Warlow 1991 Hankey et al. 1991 Mead et oL 1999). Coirfining angiography to patients with a carotid bifurcation bruit will miss some patients with severe stenosis and still subject too many with mild or moderate stenosis to the risks. Nor will a combination of a cervical bruit with various clinical features do much better (Mead et al. 1999). 

As a result of the large randomized controlled trials, it is now clear that endarterectomy of recently symptomatic severe carotid stenosis almost completely abolishes the high risk of ischemic stroke ipsiiaterai to the operated artery over the subsequent two or three years (see Ch. 27 for detailed discussion of the selection of patients for surgery). Moreover, this effect is durable over at least 10 years (European Carotid Surgery Trialists Collaborative Group 1991, 1998 Mayberg et al. 1991 North American Symptomatic Carotid Endarterectomy Trial Collaborators 1991 Barnett et al. 1998 Rothwell et al. 2003). Indeed, the ipsiiaterai stroke risk becomes so low that presumably both embolic and low-flow strokes are being prevented (Fig. 25.1). 

Fig. 27.1. Selective arterial angiograms of both carotid circulations in a patient with a recently symptomatic carotid "near occlusion" (lower left), and a mild stenosis at the contralateral carotid bifurcation (lower right).

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