Covered-stent–assisted coil embolization for coronary fistula and LIMA side-branch closure

Background Transcatheter coil embolization is an established treatment for selected coronary pathologies, including coronary artery fistulas and patent left internal mammary artery (LIMA) side branches. However, coil embolization may require multiple coils and may be associated with risks such as distal migration, residual flow, and increased procedural cost. We describe a hybrid covered-stent–assisted coil embolization approach using a proximal crushed-stent scaffold and report our early clinical experience. Methods This retrospective descriptive study included six consecutive patients who underwent covered-stent–assisted coil embolization with a crushed-stent scaffold between March 2023 and December 2025 at a single center. The technique involves deployment of a covered stent across the target segment, followed by intentional crushing of its proximal portion using a jailed noncompliant balloon to create a mechanical plug at the inlet. A microcatheter is then advanced into the crushed segment, allowing controlled coil deployment within a stabilized scaffold. Clinical characteristics, angiographic findings, procedural details, and in-hospital outcomes were analyzed. The primary procedural endpoints were total coil number, need for additional coils, and angiographic procedural success, defined as complete or near-complete occlusion with minimal residual flow. Results Three patients had congenital coronary artery fistulas and three had high-flow LIMA side branches. The mean lesion diameter was 1.9 mm, with four medium and two large lesions relative to the reference vessel. A covered stent was used in five patients and a bare-metal stent in one. Coils were deployed in five patients with a mean of 1.8 coils per lesion, while one case achieved acceptable occlusion with stent crushing alone. Procedural success was achieved in five patients (83.3%). No distal coil migration, myocardial infarction, acute kidney injury, stroke, or in-hospital death occurred. Conclusion Covered-stent–assisted coil embolization using a proximal crushed-stent scaffold appears to be a simple and reproducible technique for percutaneous closure of selected coronary lesions. By creating a stable mechanical plug at the lesion entry, the approach may reduce coil burden and migration risk while maintaining satisfactory procedural success. Larger studies with longer follow-up are needed to confirm durability and clinical benefit.