Anticoagulation in Ischemic Stroke With Hemorrhagic Transformation With Concurrent Mitral Valve Thrombus Following CABG and Bioprosthetic MVR : A Case Report

Cerebrovascular accidents (CVAs) are a well‐documented, albeit feared, complication of coronary artery bypass grafting (CABG) and mitral valve replacement (MVR) procedures. Fortunately, CVA risk following these procedures has decreased in recent years, with reported rates of 1.2%–7.4%. We present a unique case of a large right middle cerebral artery (MCA) ischemic stroke with subsequent hemorrhagic conversion after CABG and MVR, further complicated by a thrombus on the replaced mitral valve. The patient is a 60‐year‐old man with a past medical history significant for heart failure with reduced ejection fraction (HFrEF) (ejection fraction 25%–35%), severe mitral regurgitation, cannabis use, and coronary artery disease who presented for an elective bioprosthetic MVR. The patient underwent an MVR with a 27 mm bioprosthetic valve and CABG. Postoperatively, he developed an ischemic stroke, concerning for embolic etiology of unknown source, which underwent hemorrhagic transformation. Stroke workup revealed a thrombus on the replaced mitral valve. Through multispecialty discussion, a decision was made to attempt anticoagulation for secondary prevention of another stroke. Repeat computed tomography (CT) revealed worsening of intracranial hemorrhage (ICH). This created a complex scenario where the patient needed anticoagulation but was not able to because of the hemorrhagic stroke. The patient was eventually discharged to a rehabilitation facility on postoperative day 38. Further research is needed to refine perioperative stroke prevention and develop evidence‐based protocols for anticoagulation timing and dosing in patients with concurrent hemorrhagic stroke and valve thrombus. Valve thrombus characteristics and hemodynamic impact should guide therapy, and anticoagulation should not begin until intracranial stability is confirmed through serial imaging.