Anand Sarma
Wake Forest Baptist Health
Winston Salem, North Carolina, United States
Disclosure information not submitted.
Lahiru Ranasinghe, MD
Resident
Wake Forest Baptist Health
Winston Salem, North Carolina, United States
Disclosure information not submitted.
Sudhir Datar, MD
Assistant Professor
Wake Forest Baptist Health, United States
Disclosure information not submitted.
Kyle Fargen, MD MPH
Associate Professor
Wake Forest Baptist Health, United States
Disclosure information not submitted.
Adrian Lata, MD
Professor
Wake Forest Baptist Health, United States
Disclosure information not submitted.
Aarti Sarwal, MD, FAAN, FNCS,FCCM
Medical Director, Neurocritical Care
Wake Forest Baptist Health Center
Winston-Salem, North Carolina
Disclosure information not submitted.
Title: Dynamic cerebral steal syndrome after subclavian carotid bypass procedure uncovered with TCD
Case Report Body
Introduction: Carotid steal syndrome is an extremely rare but recognized complication that can occur after carotid subclavian bypass performed for proximal subclavian occlusion/stenosis. Steal can be dynamic leading to missed diagnosis. We describe a unique case of cerebral steal uncovered by ultrasound leading to appropriate management.
Description: A 62-year old patient underwent left carotid-subclavian bypass as part of endovascular repair of a complicated acute type B aortic dissection further complicated post operatively by right hemiparesis and aphasia concerning for left middle cerebral artery ischemic stroke. CTA head and neck showed no definite intra or extracranial occlusion but a non-occlusive left subclavian artery (SCA) thrombus. Fluctuating exam incited repeat CTA revealing occlusion of left SCA proximal to bypass with possible left common carotid artery (CCA) occlusion necessitating anticoagulation. Repeat stroke symptoms incited cerebral angiogram that showed no thrombotic lesions, and contrast stagnation in left CCA with patent graft. Transcranial Doppler (TCD) showed steal waveforms in left internal and external carotid arteries, anterior and middle cerebral arteries intracranially, and reversed left vertebral in the neck, made worse by left arm exercise concerning for downstream findings of left CCA occlusion and steal through the subclavian graft. Cuff inflation of left arm to increase distal vascular resistance targeted towards reducing steal reverted waveforms to near complete forward flow. Original steal waveforms reverted after cuff release confirming bypass steal. Further surgical re-exploration found occluded bypass and left CCA with reversed left vertebral artery supplying distal arm. Emergent revision of the bypass and left CCA stenting was done after thrombectomy. TCD waveforms reverted to physiological flow.
Discussion: This patient presented a diagnostic challenge of post-operative stroke due to dynamic cerebral steal complicated by stenosis of graft and occlusion of left CCA proximal to the graft. This incited a collateral circuit through L vertebral supplying the arm by intracranial steal. TCD with cuff testing led to appropriate diagnosis and intervention. This modality should be considered in cerebrovascular assessment after vascular procedures involving the carotid circulation.