Balloon‐Assisted Embolization of a Left Internal Mammary Artery Branch in Life‐Threatening Hemoptysis: A Case Report

Life-threatening hemoptysis is most commonly caused by hypertrophied bronchial arteries, but non-bronchial systemic arteries (NBSA) such as the left internal mammary artery (LIMA) may also contribute, particularly in chronic infectious lung diseases. Embolization of LIMA branches poses technical challenges due to their tortuosity and proximity to critical vascular territories. Balloon-assisted microcatheter techniques have emerged as valuable tools for achieving precise and safe embolization in such complex vascular anatomies. A 62-year-old man with a history of pulmonary tuberculosis presented with recurrent massive hemoptysis despite four prior bronchial artery embolizations. CT angiography and selective left subclavian angiography revealed two hypertrophied LIMA branches supplying the diseased parenchyma of the left lung. Using a transradial approach, balloon-assisted microcatheter embolization was performed with 500-710 μm PVA particles. The balloon was inflated distal to the bleeding branch to achieve temporary flow arrest, allowing controlled and targeted embolization. Post-procedural angiography confirmed complete occlusion of the abnormal branches with preserved antegrade flow in the main LIMA trunk. The patient recovered uneventfully and remained asymptomatic at 4-week and 3-month follow-ups. Balloon-assisted microcatheter embolization enables safe, selective occlusion of LIMA-derived NBSA feeders in life-threatening hemoptysis, minimizing the risk of non-target embolization and preserving the LIMA for potential future CABG use. This case demonstrates the technique's clinical utility in complex, high-risk vascular anatomies.