Case of a Man With Subclavian Steal Syndrome

Key TakeawaysThis case highlights a rare combination of vascular and cervical spine disease presenting with unilateral weakness, arm symptoms, and asymmetric arm blood pressures. Imaging confirmed significant subclavian and vertebral flow abnormalities alongside bilateral carotid stenosis and cervical cord compression, and the symptoms were felt to be most consistent with autonomic dysregulation from subclavian steal syndrome (SSS).The case report by medical student Lara Zargarian and colleagues from Kansas City University in Joplin, Missouri, documents a rare constellation of vascular diseases.The Patient and His Medical HistoryThe patient presented to the emergency department of a hospital in Joplin with weakness on the right side, a pulsating sensation in the distal right arm, and pain in the right arm that radiated into the fingers.His known preexisting conditions included SSS, arterial hypertension, hypercholesterolemia, and hyperlipidemia. He reported being a 36-pack-year smoker.More than 20 years ago, spinal surgery had been performed at the C5/C6 and C6/C7 levels of the cervical spine. In addition, meniscus surgery had been performed 14 years ago.Other than the conditions noted above, the patient’s medical, family, social, substance use, travel, and allergy histories were unremarkable.FindingsUpon admission, the patient’s vital signs were measured. Respiratory and heart rates, blood pressure, oxygen saturation on room air, and body temperature were within their respective normal ranges.Inspection, auscultation, palpation, and percussion of the patient’s body revealed no significant findings.However, a precise blood pressure measurement revealed a lateral difference between the arms. The systolic blood pressure on the right was 140 mm Hg; on the left, it was 112 mm Hg.Diagnosis and TreatmentA duplex ultrasound revealed 50% stenosis of the internal carotid arteries on both sides. The maximum systolic velocity in the right subclavian artery was 318 cm/s with a monophasic waveform. There was marked retrograde flow in the left vertebral artery.MRI of the cervical spine revealed degenerative bony changes with bilateral, mildly narrowed neural foramina (more pronounced on the right) and mild central canal stenosis. At the C3-C4 and C4-C5 levels, severe flattening of the spinal cord was observed. Multiple intervertebral disc spaces were narrowed.Following a multidisciplinary case conference, the decision was made to perform surgical treatment of the severe stenoses in order to partially alleviate the symptoms.Discussion“Autonomic dysregulation secondary to SSS can mimic various conditions leading to some challenges in the treatment course for symptomatic patients,” the authors of the case report wrote. Although degenerative changes in the spine may have caused some of the symptoms in this case through nerve damage, the primary condition was likely the autonomic dysregulation caused by SSS.This article was translated from Univadis Germany, part of the Medscape Professional Network.