Suspected native aortic valve thrombosis complicated by recurrent left main coronary artery embolism and acquired Gerbode defect: a case report

Native aortic valve thrombosis (NAVT) is an uncommon cause of coronary embolism and myocardial infarction. In patients with severe aortic valve disease treated surgically, a post-operative communication between the left ventricle and right atrium (i.e. acquired Gerbode defect) is a rare complication.

We report the case of a 67-year-old man with suspected NAVT presenting with myocardial infarction and a post-operative acquired Gerbode defect. Coronary angiography showed a floating thrombus in the left main coronary artery without significant culprit-vessel atherosclerotic disease, suggesting coronary embolism. Multiple aspiration thrombectomies and glycoprotein IIb/IIIa inhibitor therapy were performed. Recurrent chest pain prompted repeat coronary angiography, which confirmed thrombus recurrence and resolution after repeat treatment. Intravascular ultrasound excluded significant culprit-vessel atherosclerotic disease. Aspirated material revealed a subacute thrombus with microcalcifications on histopathological examination. Echocardiography showed severe calcific aortic stenosis, a likely predisposing factor for NAVT. Atrial fibrillation had not been documented during the embolic event or previously and was only detected later during hospitalization, prompting initiation of anticoagulation (CHA2DS2-VASc score 3). Consequently, dual antiplatelet therapy was replaced with apixaban and ticagrelor until surgery. After clinical stabilization, the patient underwent surgical aortic valve replacement. No left atrial appendage thrombus was found intra-operatively after 3 months of anticoagulation. Post-operatively, multimodal imaging identified and quantified an acquired Gerbode defect. Given its haemodynamic insignificance, a conservative approach was adopted.

This case highlights underreported complications of severe aortic stenosis and its treatment, emphasizing the importance of multimodal imaging in the diagnosis of NAVT and post-operative Gerbode defect.