Imaging-driven procedural strategies for coronary subclavian steal syndrome: Two cases of severe calcification and dual branch protection

Coronary subclavian steal syndrome (CSSS) is an uncommon cause of myocardial ischemia in patients undergoing coronary artery bypass grafting using an internal thoracic artery conduit. Endovascular treatment is the preferred treatment, although procedural strategies should be tailored to lesion characteristics and anatomical complexity. We report 2 cases of CSSS successfully treated with endovascular treatment. In the first case, a 75-year-old man had severe nodular calcified stenosis of the proximal left subclavian artery, requiring stepwise balloon dilatation followed by covered stent deployment. In the second case, an 83-year-old man had severe proximal left subclavian artery stenosis with a limited landing zone between the origins of the left vertebral artery and internal thoracic artery, accompanied by bilateral vertebral artery disease. Balloon protection of both branches was performed during stent deployment to preserve coronary and vertebrobasilar perfusion. These cases highlight the importance of individualized endovascular treatment strategies based on lesion morphology and branch vessel anatomy, including careful lesion preparation and branch protection in complex CSSS.