SHM Converge Scientific Abstract ePoster Gallery-Trauma Induced Intracranial Hypotension (Ih): A Cause of Orthostatic Headache

Pdf Summary

This case describes a 75-year-old man with prior coronary artery bypass grafting (CABG) using a left internal mammary artery to left anterior descending artery graft (LIMA-LAD), who presented 15 years later with positional/exertional chest pain and dizziness. Evaluation showed a marked systolic blood pressure difference of about 40 mmHg between arms, suggesting left subclavian artery disease.<br /><br />CT angiography confirmed severe stenosis at the ostium of the left subclavian artery, proximal to the LIMA origin. Catheterization demonstrated a 40 mmHg pressure gradient between the left subclavian artery and the aorta, consistent with coronary subclavian steal syndrome (CSSS). In CSSS, proximal subclavian stenosis reduces forward flow through the LIMA graft and can cause retrograde flow, compromising coronary perfusion and producing angina or even myocardial infarction.<br /><br />The lesion was not suitable for percutaneous stenting, so vascular surgery performed a carotid-subclavian bypass. After surgery, the inter-arm blood pressure difference fell to less than 5 mmHg, and the patient’s chest pain and dizziness resolved.<br /><br />The report emphasizes several clinical points: CSSS is an important but uncommon complication in patients with LIMA-LAD grafts and can occur in 0.2%–6.8% of such patients. A systolic blood pressure difference of 20 mmHg or more between arms may be an early clue. Annual bilateral brachial blood pressure measurements after CABG can help screen for subclavian stenosis. Recognizing and treating subclavian artery stenosis is critical because it can lead to ischemia, infarction, and sudden cardiac death. ESC guidelines generally recommend endovascular treatment first for symptomatic disease, with surgery as an alternative when stenting is not feasible.

Asset Subtitle

Prasanti A. Kotta

Meta Tag

Author List Huilin Yang, James Tran, Madhivanan Elango, Prasanti A. Kotta

Category Clinical Vignettes

Concept Coronary Subclavian Steal Syndrome

Concept Post-CABG Chest Pain

Concept Left Internal Mammary Artery-Left Anterior Descending Artery Graft

Concept Subclavian Artery Stenosis

Concept Inter-Arm Blood Pressure Difference

Distinguished Non-Finalist

Presenter Organization Baylor College of Medicine

Presenting Author Prasanti A. Kotta

Track Adult

Keywords

coronary subclavian steal syndrome

LIMA-LAD graft

left subclavian artery stenosis

coronary artery bypass grafting

inter-arm blood pressure difference

carotid-subclavian bypass

angina

myocardial ischemia

CT angiography

endovascular stenting

Coronary Subclavian Steal Syndrome

Post-CABG Chest Pain

Left Internal Mammary Artery-Left Anterior Descending Artery Graft

Subclavian Artery Stenosis

Inter-Arm Blood Pressure Difference