Giant Coronary Artery Aneurysm at the Left Main Bifurcation Managed With Stent-Assisted Endovascular Coil Embolization

Giant coronary artery aneurysms (CAAs), defined as exceeding 4 times the reference vessel diameter or 20 mm, are rare, with no randomized trials or guidelines directing treatment. A 78-year-old woman with exertional angina was found to have a 30 mm giant CAA at the left main (LM) bifurcation with 70% mid-LM and ostial left anterior descending stenosis. Given poor surgical candidacy, a fully percutaneous approach was used: a drug-eluting stent was placed from the distal LM into the proximal left anterior descending, followed by stent-assisted coil embolization with 13 detachable coils. Final angiography showed no residual stenosis, near-complete aneurysm exclusion, and restoration of TIMI flow grade 3 in the left circumflex artery, suggesting the aneurysm had been causing coronary steal. The patient was discharged chest pain-free on dual antiplatelet therapy. This case demonstrates stent-assisted coil embolization as a viable percutaneous option for giant LM bifurcation CAAs and highlights coronary steal as a potential consequence.