Intraprocedural Fibrin Clot Formation During Pulmonary Vein Isolation With a Lattice‐Tip Ablation Catheter

Introduction Pulsed‐field ablation with a lattice‐tip catheter has emerged as a promising technology for pulmonary vein isolation. We report a case of intraprocedural catheter malfunction with fibrin deposition potentially leading to a transient neurological deficit during ablation despite optimal anticoagulation. Case A 39‐year‐old man with symptomatic atrial fibrillation and tachycardia‐mediated cardiomyopathy underwent pulmonary vein isolation using the Affera mapping system and Sphere‐9 lattice tip catheter. During the procedure, despite uninterrupted oral anticoagulation and heparin given to meet manufacturer‐recommended activated clotting times, the catheter malfunctioned, and when removed, there was a white solid substance that was seen within the lattice tip. The procedure was stopped prematurely with incomplete pulmonary vein isolation. A pathologist confirmed the white substance was fibrin inside the lattice tip. The patient had symptoms of transient ischemic attack postoperatively and also suffered early recurrence of atrial fibrillation. Conclusion This case demonstrates fibrin deposition and possible embolic events using the Sphere‐9 lattice tip catheter despite stringent anticoagulation protocols. This highlights the importance of meticulous catheter inspection as well as provides a post‐market complication utilizing this catheter.