Abstract Background Left ventricular pseudoaneurysm (LVP) is a rare complication of myocardial infarction MI (less than 0,1% of all patients with MI) and develops when cardiac rupture is contained by adherent pericardium or scar tissue, thus contains no endocardium or myocardium, unlike a true left ventricular aneurysm (LVA). Clinical Case A 41–year–old man without remote cardiac history was admitted to the Emergency Department with chest pain that had started 7 days before after a referred ‘big hug’ from a friend. Results of the physical examination were unremarkable. Electrocardiogram: T waves negative in the inferior and lateral leads. Blood exams: normal troponins, C–reactive protein and D–dimer values. Chest computed tomography: no sign of pulmonary embolism. Transthoracic echocardiography (TE): ejection fraction 45%, voluminous aneurismal chamber communicating with the infero–posterior wall of the LV, stratified thrombus and mild mitral valve regurgitation. Coronary angiography: three vessel coronary artery disease. The last diagnosis was established by cardiac magnetic resonance imaging (MRI) which revealed a voluminous pseudoaneurysm of the inferior wall (56 mm x 50 mm with a 51 mm neck) and transmural late gadolinium enhancement (LGE) of the wall adjacent to the pseudoaneurysm with fibroadipose replacement and calcific metaplasia. The patient was transferred to the Cardiac Surgery Department. Intraoperatively the LVP was resected and the defect of the LV was repaired with a patch in bovine pericardium. In addition, coronary artery bypass grafting and mitral valve repair were performed. Discussion LVP develops when pericardium, in combination with thrombus and inflammation, surrounds a cardiac rupture. Inferior and posterolateral myocardial infarction (MI), due to occlusion of the Circumflex artery, are responsible for 82% of the LVP. LVP can be also found in the apical region due to anterior MI. In conclusion symptoms, signs, electrocardiographic abnormalities and radiographic findings seen in patients with LVP can be indistinguishable from those in patients with coronary disease alone. TE is the first non–invasive method for early diagnosis of LVA, but MRI is the gold standard for differential diagnosis between true aneurysm vs pseudoaneurysm. LGE of the pericardium is a new specific marker of pseudoaneurysm as opposed to true aneurysm.