Coronary-subclavian steal syndrome caused by proximal left subclavian artery stenosis was successfully treated with percutaneous stent placement in a post-CABG patient, restoring antegrade LIMA-LAD graft flow and resolving myocardial ischemia.
Key Findings
Background
Coronary-subclavian steal syndrome (CSSS) is a rare but clinically significant cause of myocardial ischemia in post-CABG patients with LIMA grafts due to proximal subclavian artery stenosis causing reversal of graft flow.
CSSS occurs when proximal subclavian artery stenosis leads to reversal of LIMA graft flow, resulting in compromised myocardial perfusion
The condition can mimic progression of native coronary artery disease, making diagnosis challenging
The left internal mammary artery (LIMA) used as a conduit to the left anterior descending artery (LAD) is particularly implicated
Results
A 63-year-old post-CABG patient presented with progressive exertional chest pain and left upper-extremity paresthesia consistent with CSSS.
The patient had a history of multi-vessel coronary artery disease, prior percutaneous coronary intervention (PCI), and CABG with a LIMA-to-LAD graft
Physical examination revealed a diminished left radial pulse and inability to obtain blood pressure in the affected arm
These bedside findings raised suspicion for a proximal inflow lesion prior to advanced imaging
Results
CTA identified high-grade stenosis of the proximal left subclavian artery, and coronary angiography confirmed underfilling of the LIMA-LAD graft consistent with CSSS physiology.
CTA was used as the initial advanced imaging modality to identify the subclavian lesion
Coronary angiography demonstrated underfilling of the LIMA-LAD graft, confirming the steal physiology
The combination of targeted vascular imaging and bedside examination facilitated the diagnosis
Results
Percutaneous balloon-expandable stent placement was selected and successfully deployed, restoring antegrade LIMA-LAD graft flow with immediate improvement in graft perfusion.
Endovascular intervention was chosen over medical therapy and redo surgical revascularization due to its lower procedural morbidity and favorable reported outcomes
A balloon-expandable stent was used for the subclavian artery intervention
Immediate restoration of antegrade flow was achieved following stent deployment
Conclusions
The authors developed a practical diagnostic flowchart to support clinical evaluation and management of suspected CSSS in post-CABG patients.
The flowchart was designed to guide clinicians through evaluation of recurrent angina and upper-extremity vascular findings in post-CABG patients
Key diagnostic steps included bedside examination findings such as diminished radial pulse and blood pressure differential between arms
The flowchart addresses decision-making among medical therapy, endovascular intervention, and surgical revascularization
Conclusions
Endovascular subclavian revascularization was characterized as a safe and effective treatment for CSSS, avoiding the higher morbidity of redo surgical revascularization.
The case supports percutaneous stent placement as a preferred approach given lower procedural morbidity compared to redo surgery
The intervention resulted in resolution of the steal physiology and restoration of graft perfusion
The authors noted favorable reported outcomes for endovascular intervention in the literature
What This Means
This research describes a case of a 63-year-old man who had previously undergone heart bypass surgery using an internal mammary artery (a blood vessel from the chest wall) to supply blood to his heart. Years later, he developed a narrowing in the subclavian artery — the large vessel in the shoulder that the mammary artery branches from — which caused blood to flow backward through his bypass graft and away from his heart instead of toward it. This condition, called coronary-subclavian steal syndrome, caused his chest pain to return and also produced numbness and tingling in his left arm, with doctors unable to measure blood pressure in that arm due to reduced flow.
This research suggests that simple bedside examination clues — such as a weak pulse or absent blood pressure in one arm — can point doctors toward this diagnosis before expensive or invasive testing, and that a combination of CT scanning and cardiac catheterization can confirm it. Rather than repeating open-heart surgery, the medical team chose to place a small metal stent (a mesh tube) inside the narrowed subclavian artery using a minimally invasive catheter-based approach. This immediately restored normal blood flow through the bypass graft and resolved the patient's symptoms.
This case matters because CSSS can be mistaken for worsening of the original heart disease, potentially leading to unnecessary or inappropriate treatments. This research suggests that clinicians should consider subclavian artery disease as a reversible cause of recurring chest pain in anyone who has had bypass surgery using a mammary artery graft, and that a straightforward endovascular procedure can effectively correct the problem with lower risk than repeat open-heart surgery. The authors also provide a step-by-step decision guide to help other clinicians recognize and manage similar cases.
Rayyan A, Bishev D, Nawaz N. (2026). Coronary-Subclavian Steal Syndrome in a Post-Coronary Artery Bypass Grafting Patient: A Reversible Cause of Myocardial Ischemia.. The American journal of case reports. https://doi.org/10.12659/AJCR.951303