Key Clinical Message:
Early recognition and diagnosis of subclavian steal syndrome are vital
to avoid unnecessary investigations and ensure appropriate management.
This case highlights the significance of comprehensive evaluation,
including bilateral blood pressure measurement, in patients with
unilateral symptoms.
Keywords: subclavian steal; angioplasty; stenting; dual
antiplatelet therapy
A 60-year-old woman with a history of hypertension presented to our
hospital’s Internal Medicine Outpatient Department with an 8-month
history of persistent left upper extremity numbness and dizziness,
exacerbated by using her left hand for heavy lifting. She had never
experienced chest pain, palpitations, tinnitus, hearing loss, or
positional vertigo. Despite visiting multiple healthcare providers,
including orthopedic and psychiatric specialists, and undergoing various
diagnostic tests, her symptoms persisted. Notably, blood pressure
measurements were not taken in both upper extremities during previous
evaluations. A thorough physical examination revealed significant blood
pressure differences between the two upper extremities, with the right
upper extremity’s BP being 170/100 mm of Hg and the left upper
extremity’s BP being 110/70 mm of Hg. In addition, the patient’s left
radial pulse was weak. Initial laboratory evaluations, such as a
complete blood count, liver function test, renal function test, and
fasting lipid profile, were within normal limits. Considering the
absence of cardiac abnormalities on electrocardiogram and
echocardiography, the suspicion of vascular occlusion emerged as a
plausible cause for the patient’s symptoms. Consequently, we referred
her to a higher center for specialized evaluation. After referral, she
was seen by a cardiologist, and he confirmed the blood pressure
discrepancies between the two upper extremities. She underwent an
angiography of the left subclavian artery, and it revealed a significant
occlusion in the proximal left subclavian artery (Figure 1), thus
hinting towards subclavian artery stenosis. Elective angioplasty of the
left subclavian artery with stenting was scheduled for one week after
the diagnosis. Following the angioplasty and stenting procedure, the
angiogram showed complete restoration of blood flow in the left
subclavian artery with visualization of anterograde blood flow in the
left vertebral artery as well (Figure 2). The patient also experienced a
notable improvement in her symptoms. The blood pressure discrepancy was
corrected after the procedure. She was placed under dual antiplatelet
therapy (Aspirin and Clopidogrel) and a statin after the procedure. She
no longer complains of numbness in her left upper extremity or
dizziness. She is on constant follow-up with us.
Subclavian steal syndrome (SSS) is a vascular condition characterized by
the narrowing or blockage of one of the subclavian
arteries.1 Symptoms of subclavian stenosis include
exercise-induced arm pain or fatigue (arm claudication), occasional
coolness or paresthesias in the extremity, and rarely, vertebrobasilar
transient ischemic attacks. The diagnosis of SSS can be suggested by
flow reversal in the ipsilateral vertebral artery on Doppler ultrasound.
The subclavian stenosis or atresia can be documented by catheter X-ray
angiography.2 Endovascular treatment, including
balloon angioplasty and stenting, has become popular due to its
minimally invasive nature and comparable outcomes.3
Early recognition and diagnosis of subclavian steal syndrome are vital
to avoid unnecessary investigations and ensure appropriate management.
This case highlights the significance of comprehensive evaluation,
including bilateral blood pressure measurement, in patients with
unilateral symptoms. Increased awareness among healthcare providers and
timely referral to specialized centers can lead to successful
revascularization, symptom resolution, and improved outcomes.