Subclavian Artery Stenosis
Definition:
Like any other major arteries, subclavian arteries which supply blood to the brain and upper extremities (arms) are also susceptible to blockages.
Subclavian artery stenosis is a narrowing of one or both of the main arteries supplying blood to the brain and arms.
Subclavian artery stenosis can be a cause of significant morbidity as it can lead to symptomatic ischemic issues affecting the upper extremities, brain and in some cases, the heart.
Symptoms:
Vascular occlusive disease of the subclavian artery may be asymptomatic or may be associated with symptoms of cerebral or arm ischemia.
The left subclavian artery is four times more likely to be affected than the right subclavian or innominate arteries.
Obstructive disease of these arteries affects other aortic arch vessels, namely the carotid or vertebral arteries, also the likelihood of steal or ischemic symptoms drastically increases.
Your doctor may also suspect a problem if you have:
Upper extremity symptoms can include arm claudication, muscle fatigue and pain.
Finger necrosis from embolic debris.
Vertebrobasilar insufficiency.
Splinter hemorrhages.
Blue finger syndrome.
Vertigo.
Cardiac ischemic symptoms, in case an internal mammary artery is involved.
Causes:
The 2 most common causes of subclavian artery stenosis are:
Atherosclerosis: Fatty plaque builds up in the arteries and blocks blood flow to the brain and arms. This occurs mainly in men over 50 years old.
Vasculitis/Arteritis: Takayasu syndrome
Inflammation due to radiation exposure.
Compression Syndromes
Fibromuscular dysplasia
Neurofibromatosis
Trauma
Risk Factors:
Following people are at high risk of subclavian artery stenosis vascular disease and should get themselves evaluated by expert doctors:
Smoker
Diabetic
A family History of heart diseases, diabetes, hypertension
Obese/overweight
Physically inactive
Age - Over 50 years
Examination:
While the definitive diagnosis typically rests on imaging, the importance of a thorough physical exam must not be underscored.
On examination, patients can display unequal arm blood pressures, absent or significantly diminished pulses (axillary, brachial and radial/ulnar) in comparison to the contralateral arm, and cervical or supraclavicular bruits.
Such patients must be examined for:
Finger ulcers
Gangrenous skin changes in the nail bed
Splinter hemorrhages
Palpation of carotid pulses
Auscultation for vertebral (sub-occipital region) and carotid bruits
Once a significant blood pressure difference is found, the next step should involve diagnostic imaging.
Duplex ultrasound with color flow is the non-invasive modality of choice.
Treatment:
Treatment options include:
Medical Therapy
In patients who have atherosclerotic occlusions in the great arch vessels, it is important to treat them with antiplatelet therapy and aggressive blood pressure control to reduce the risk of associated diseases including stroke and myocardial infarction.Endovascular Interventions
In general, percutaneous endovascular intervention with balloon expandable stents has excellent success rate and is of relatively low risk. A thin tube is cannulated from a puncture in your groin. The procedure consists of dilating the blood vessel with a balloon followed by placing the stent that opens up the narrowed blood vessel.Surgical Repair
If angioplasty cannot be done on the artery, a surgeon may decide to repair the condition through an incision from the base of the neck to the sternal notch.