Atrial Thrombus in Severe Pectus Excavatum and Patent Foramen Ovale Closure

BACKGROUND: Severe pectus excavatum (PE) can distort cardiac anatomy and alter intracardiac flow, yet its contribution to device-associated thrombosis is rarely reported. CASE SUMMARY: A 41-year-old woman with severe PE and a patent foramen ovale closed using an occluder developed recurrent pulmonary and systemic embolic events despite anticoagulation. Imaging revealed biatrial compression, resulting in biatrial injury and device-associated thrombosis. With ongoing left atrial thrombus growth and cerebral embolic events while on anticoagulation therapy, she underwent a single-stage procedure: device explantation, evacuation of thrombus, primary patent foramen ovale closure, and minimally invasive PE repair. Intraoperative transesophageal echocardiography confirmed resolution of cardiac compression and no residual thrombus. DISCUSSION: Although thrombosis after occluder placement or in PE has been described, the combination of PE-related compression, intracardiac device, and biatrial thrombus has not. Mechanical cardiac deformation likely contributed to persistent thrombogenesis. TAKE-HOME MESSAGES: Severe PE-related compression may contribute to persistent device-associated atrial thrombus despite anticoagulation. Combined repair can address the underlying mechanical cause.