Title
Acute Left Main Thrombosis Managed with Emergent Thrombectomy and IVUS-Guided Intervention Following Surgical Aortic Mechanical Valve Replacement.
Introduction
Severe aortic stenosis (AS) with concomitant atrial fibrillation presents high perioperative risk. Surgical aortic valve replacement (SAVR) combined with atrial fibrillation ablation and left atrial appendage closure can be complicated by acute coronary thrombotic events. We report a case of catastrophic left main thrombosis post-SAVR managed with emergent percutaneous intervention and mechanical circulatory support.
Clinical Case
A 56-year-old man with symptomatic severe AS, moderate aortic insufficiency, and paroxysmal atrial fibrillation underwent SAVR with a #23 On-X mechanical valve, pulmonary vein isolation, and left atrial appendage closure. Preoperative evaluation demonstrated normal biventricular function and no significant coronary artery disease. Immediately postoperatively, the patient developed sudden hypotension and refractory ventricular arrhythmias, requiring emergent sternal reopening, internal cardiac massage, and initiation of central VA-ECMO. Urgent coronary angiography revealed complete thrombotic occlusion of the left main artery. A 6Fr XB 3.5 guiding catheter was advanced to the ostium, re-establishing antegrade flow even prior to wire crossing. Intravascular ultrasound (IVUS) confirmed extensive thrombus burden, and mechanical thrombo-aspiration successfully retrieved large quantities of thrombotic material. Despite initial angiographic success and restored TIMI III flow, hemodynamic instability persisted. Repeat coronary angiography at 24 hours showed patent vessels without residual thrombus, confirming adequate reperfusion. The patient subsequently underwent multiple mediastinal washouts and left atrial vent placement due to volume overload and developed extensive left-hemisphere ischemic stroke. Attempts to wean VA-ECMO were complicated by recurrent instability; arterial cannula dislodgement on postoperative day 14 led to cardiogenic shock and, unfortunately, death.
Discussion
This case illustrates the technical and clinical challenges of emergent left main thrombosis following combined SAVR and atrial fibrillation ablation. IVUS-guided intervention and mechanical thrombo-aspiration enabled immediate restoration of coronary flow, emphasizing the role of advanced percutaneous strategies in critical postoperative settings. Despite procedural success, ongoing hemodynamic instability and neurologic complications highlight the complexity of care and the limits of intervention in high-risk surgical patients. Multidisciplinary coordination between interventional cardiology, cardiac surgery, and critical care is essential for optimizing outcomes in these rare but catastrophic events.