External Outflow Graft Stenosis in HeartMate 3 Left Ventricular Assist Devices: The Dangers of Stenosis Migration

External outflow graft obstruction (eOGO) is an increasingly recognized long-term complication in patients with HeartMate 3 left ventricular assist devices. While percutaneous treatment provides a less invasive alternative to surgery, it introduces the challenge of stenosis migration-especially when graft twist is a contributing factor. This migration can extend to the edge or even beyond the Bend Relief toward the aortic or pump anastomosis, posing procedural risks in fragile anatomical zones. In this case series, we present three patients with eOGO who experienced migration of the stenotic lesion during percutaneous treatment. In the first case, the procedure was aborted due to lesion migration close to both anastomotic sites. In the second, full-graft stenting resolved the obstruction but required stenting close to the aortic anastomosis, raising concern for rupture. In the last, a preemptive "migration-aware" strategy-placing a protective stent near the anastomosis before treating the main lesion-safely contained the obstruction and prevented high-risk migration. We propose that in patients with obstruction migration or when the initial stenosis is already near an anastomotic site, clinicians should consider a migration-aware stenting strategy. This approach may help avoid uncontrolled stenosis shifts, reduce the need for high-risk anastomotic stenting, and improve procedural safety.