What is Subclavian Steal Syndrome?

From the Guidelines

Subclavian steal syndrome should be treated with endovascular procedures such as angioplasty with stenting in symptomatic patients, as this approach offers a less invasive correction of the blockage and is associated with high rates of success and better outcomes compared to angioplasty alone 1.

Diagnosis and Treatment

Subclavian steal syndrome occurs when there is a blockage in the subclavian artery before it branches to the vertebral artery, causing blood to flow backward from the brain to the arm during arm exercise. This reversal of blood flow "steals" blood from the brain, potentially causing neurological symptoms. Most patients are asymptomatic, but some experience dizziness, vertigo, visual disturbances, or arm fatigue during exertion.

Key Points

• Diagnosis typically involves ultrasound, MRI, or angiography to confirm reversed vertebral artery flow.
• Asymptomatic patients generally require no intervention beyond managing cardiovascular risk factors like smoking cessation, blood pressure control, and cholesterol management.
• For symptomatic patients, endovascular procedures such as angioplasty with stenting are the preferred treatment, offering less invasive correction of the blockage.
• Surgical bypass may be necessary in complex cases.
• The condition results from atherosclerosis in most cases, though other causes include congenital abnormalities or trauma.
• Blood pressure measurements often show a significant difference between arms (>20 mmHg), which can be an important clinical clue to the diagnosis. Some key considerations in the management of subclavian steal syndrome include:
• The use of extra-anatomic carotid-subclavian bypass as a reasonable option for patients with symptomatic posterior cerebral or cerebellar ischemia caused by subclavian artery stenosis or occlusion 1.
• The role of percutaneous endovascular angioplasty and stenting as a reasonable option for patients with symptomatic posterior cerebral or cerebellar ischemia caused by subclavian artery stenosis 1.

Management

The management of subclavian steal syndrome depends on the severity of symptoms and the presence of any underlying conditions that may be contributing to the development of the syndrome. In general, the goal of treatment is to restore normal blood flow to the brain and arm, and to prevent further complications. This can be achieved through a combination of lifestyle modifications, medical therapy, and surgical or endovascular interventions. It is essential to individualize treatment based on the specific needs and circumstances of each patient, taking into account factors such as the severity of symptoms, the presence of any underlying medical conditions, and the patient's overall health status 1.

From the Research

Definition and Symptoms of Subclavian Steal Syndrome

• Subclavian steal syndrome is a condition characterized by the reversal of blood flow in the vertebral artery due to a stenotic or occlusive lesion in the subclavian artery 2.
• Symptoms of subclavian steal syndrome include paroxysmal vertigo, drop attacks, and arm claudication, which are caused by compromised vertebrobasilar and brachial blood flows 2.
• The syndrome can also present with symptoms such as syncope and left upper arm weakness, suggesting ischemia of the cerebral and left upper arm circulation 3.

Diagnosis of Subclavian Steal Syndrome

• Diagnosis of subclavian steal syndrome can be made using various imaging techniques, including Doppler ultrasound, CT angiography, and MR angiography 2, 4.
• Volume-plethysmographic blood pressure measurements can also be used to clarify the differences between the upper arms simultaneously 3.
• A high-resolution Doppler instrument can reveal a retrograde left vertebral artery waveform, indicating subclavian steal syndrome 3.

Treatment of Subclavian Steal Syndrome

• Treatment of subclavian steal syndrome can be conservative or surgical, with percutaneous angioplasty and stenting being a widely favored surgical approach 2, 4.
• Stent implantation via a femoral approach using the latest equipment can be an effective treatment for subclavian steal syndrome 3.
• Endovascular revascularization has emerged as a first-line treatment for coronary-subclavian steal syndrome, with high patency rates and low morbidity and mortality 5, 6.

Coronary-Subclavian Steal Syndrome

• Coronary-subclavian steal syndrome is a variation of subclavian steal syndrome, characterized by inversion of flow in the internal thoracic artery used as a conduit in myocardial revascularization 5, 6.
• Diagnosis of coronary-subclavian steal syndrome must be suspected in patients with difference in pulse and arterial pressure in the upper limbs, presenting with angina pectoris and a history of myocardial revascularization 6.
• Left subclavian artery stenting is a safe and effective method to treat coronary-subclavian steal syndrome, with high technical and clinical success rates 6.