CAROTID ARTERY STENOSIS

Introduction

Internal carotid artery stenosis is a chronic disease with the progressive course and serious complications. It is associated with a gradual reduction of the lumen of the main artery that supplies blood to the brain. The course of the disease may be asymptomatic or symptomatic. Stroke is the most dangerous complication. Central nervous system ischemia is usually sudden and has a rapid course. It often results in permanent disability.  

Causes

In over 90% of cases, stenosis is caused by obliterative atheromatosis. Less common causes include radiation therapy, vasculitis, delamination or fibromuscular dysplasia. The main risk factors for atherosclerosis are smoking, lipid metabolism disorders (hypercholesterolaemia), hypertension and diabetes.

Symptoms

Symptomatic carotid artery stenosis causes a neurological defect, transient ischemic attack (TIA) or stroke within the recent 6 months. The symptoms include paresis, paralysis, sensory disturbances on the side opposite to stenosis, as well as speech disorders if the artery on the side of the dominant hemisphere is narrowed. Visual disturbance occurs on the side of stenosis.

Diagnosis

Sometimes, murmur can be heard over the carotid artery in the area of the mandibular angle. It appears with the narrowing of more than 50% of the lumen. Usually, no sound is heard with the stenosis > 90% or occlusion. Colour Doppler ultrasound is used to confirm the diagnosis and determine the degree of stenosis. In some cases, it is helpful to extend imaging diagnostics to include computed tomography angiography and magnetic resonance imaging.

Treatment

Conservative treatment is based on the elimination of risk factors (giving up smoking, treatment of hyperlipidemia, hypertension and diabetes) and the use of antiplatelet drugs. Symptomatic patients and those with artery stenosis of at least 70% are eligible for invasive treatment. Classic surgery involves a removal of the atherosclerotic plaque (endaterectomy) and widening of the internal carotid artery (using a vascular patch). An alternative is minimally invasive treatment based on vascular stent implantation. The choice of the treatment method generally depends on the experience of a centre.

Type of operation

During the endovascular procedure, an atherosclerotic lesion is forced using various catheters. Because the procedure can be complicated by stroke, stent implantation is preceded by insertion of the neuroprotection system. The system resembles a basket to catch the potential embolic material travelling with the bloodstream to the brain. After unfolding the stent and compressing it with a balloon, the system is folded and removed outside. The procedure is performed under local anaesthesia from the inguinal access.

Postoperative period

As a rule, patients are discharged home on the second day after the surgery with the recommendations to take medications, change lifestyle and report for a check-up at the Regional Outpatient Clinic of Vascular Diseases.

In the Szpital Zakonu Bonifratrów, endovascular procedures are performed by doctors from the  Regional Department of Vascular Surgery and Angiology.