Right ventricular thrombus following a left anterior descending infarction: a rare case report of a common culprit

Right ventricular (RV) thrombus is a rare complication of myocardial infarction, most often associated with inferior infarcts or pulmonary embolism. This case highlights a unique presentation of RV thrombus following an anterior ST-elevation myocardial infarction (STEMI), expanding our understanding of infarct extension patterns in left coronary dominance and underscoring the diagnostic value of advanced cardiac imaging.

A 39-year-old man presented with chest pain and dyspnoea. Electrocardiography and cardiac biomarkers confirmed an anterior STEMI. Coronary angiography revealed a thrombotic occlusion of the mid-left anterior descending artery (LAD) in a left-dominant system, treated with stenting. Four days later, transthoracic echocardiography detected an RV thrombus, which was confirmed on cardiac magnetic resonance imaging (MRI). Imaging revealed extensive myocardial infarction in the LAD territory, including the apex of both ventricles with transmural necrosis and significant microvascular obstruction. The patient was anticoagulated and subsequently received a two-chamber implantable cardioverter-defibrillator due to episodes of ventricular fibrillation. Follow-up imaging showed thrombus resolution.

This case demonstrates that anterior infarctions due to wraparound LAD occlusion can extend into the right ventricle and result in thrombus formation, even with preserved RV function. It reinforces the importance of cardiac MRI for comprehensive assessment and highlights the need for awareness of atypical infarct complications.