Incidental apical left ventricular mural thrombus late after myocardial infarction with chronic myeloid leukaemia detected by cardiac magnetic resonance: a case report

Background: Left ventricular (LV) thrombus represents a critical complication following acute myocardial infarction (MI), particularly in patients with reduced LV ejection fraction (LVEF) < 40%, extensive MI, and LV aneurysm. Chronic myeloid leukaemia (CML), a haematological malignancy, is a recognized risk factor for thrombosis. While transthoracic echocardiography (TTE) serves as a 'goalkeeper' for the initial screening modality, its sensitivity in detecting mural thrombi remains limited. Cardiac magnetic resonance (CMR) with gadolinium enhancement has emerged as the diagnostic gold standard due to its superior spatial resolution and ability to recognize thrombus. Case summary: A 47-year-old male with CML, undergoing chemotherapy and a history of extensive anterior ST elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) of the proximal left anterior descending (LAD) coronary artery, presented with exertional dyspnoea. Although serial non-contrast TTEs over 12 months revealed reduced left ventricular ejection fraction (LVEF) and extensive regional wall motion abnormalities, with pulmonary hypertension (PASP 46 mmHg), no thrombus was detected. Contrast-enhanced CMR identified a large transmural MI involving the anterior, anterolateral walls, and apex with an apical LV mural thrombus. After 3 months of warfarin therapy, the thrombus reduced in size and showed no improvement in LV systolic function (LVEF 36%). Conclusion: CMR is superior to non-contrast TTE in detecting and monitoring LV thrombus treatment. The early CMR should be considered in high-risk patients post MI, particularly in those with concomitant haematological malignancy.