Congenital pulmonary steal in subclavian artery isolation

Symptomatic subclavian steal syndrome: Report of four Moroccan cases and literature review

Introduction

Subclavian steal syndrome (SSS) is the hemodynamic phenomenon of blood flow reversal in the vertebral artery due to significant stenosis or occlusion of the proximal ipsilateral subclavian artery.

Materials and methods

Four patients with subclavian steal syndrome were treated in our center. Percutaneous radial approach was used for angioplasty, primary stenting of subclavian artery was performed, surgical techniques in particular carotid-subclavian bypass and carotid-subclavian transposition were used.

Results

We report the cases of four patients, three of which are male, with an average age of 60 years. All of them were symptomatic. Diagnosis was made by duplex ultrasound, supplemented by CT-angiography and arteriography. Endovascular treatment was attempted in all four patients, which was successful in two patients, who underwent primary stenting, and failed for the two others, for whom surgical treatment was considered. One had a subclavio-carotid bypass graft with a polytetrafluorethylene (PTFE) prosthesis and the other had a subclavio-carotid transposition. The technical results were satisfactory in all patients with symptoms resolution. The postoperative evolution was without notable complications and the postoperative checkups were satisfactory.

Discussion

There are excellent screening tools and effective medical therapies which can be instituted if the SSS is diagnosed early. When the need for revascularization arises, percutaneous modalities are favored given their proven long-term efficacy, decreased morbidity and mortality, and cost-effectiveness. Nevertheless, large, prospective, randomized and controlled trials are needed to compare the long-term patency rates between the endovascular and surgical techniques.

•

SSS is caused by the reversal of blood flow in the vertebral artery.

•

Doppler ultrasound is the ultimate screening tool for diagnosis.

•

Treatment of symptomatic SSS is always indicated.

•

Endovascular approach is the first-line treatment.

A review of subclavian steal syndrome with clinical correlation

Subclavian 'steal' phenomenon is a function of the proximal subclavian artery (SA) steno-occlusive disease, with subsequent retrograde blood flow in the ipsilateral vertebral artery (VA). The symptoms from the compromised vertebrobasilar and brachial blood flows constitute the subclavian steal syndrome (SSS), and include paroxysmal vertigo, drop attacks and/or arm claudication. Once thought to be rare, the emergence of new imaging techniques has drastically improved its diagnosis and prevalence. The syndrome, however, remains characteristically asymptomatic and solely poses no serious danger to the brain. Recent studies have shown a linear correlation between increasing arm blood pressure difference with the occurrence of symptoms. Atherosclerosis of the SA remains the most common cause. Doppler ultrasound is a useful screening tool, but the diagnosis must be confirmed by CT or MR angiography. Conservative treatment is the initial best therapy for this syndrome, with surgery reserved for refractory symptomatic cases. Percutaneous angioplasty and stenting, rather than bypass grafts of the subclavian artery, is the widely favored surgical approach. Nevertheless, large, prospective, randomized, controlled trials are needed to compare the long-term patency rates between the endovascular and open surgical techniques.