Encapsulated pseudoaneurysm post-left ventricular rupture: unusual presentation and follow-up

External cardiac rupture with the development of a pseudoaneurysm is an uncommon complication of acute myocardial infarction (AMI) and do not always have typical presentations and can be challenging to diagnose. We present the case of a 59-year-old woman with no relevant cardiovascular history whose disease course was unusual. She initially presented with chest pain, dyspnea, and fever, and was diagnosed and treated for community-acquired pneumonia. Due to persistent symptoms, she went to the hospital where an electrocardiogram showed signs of an infarction. An echocardiogram revealed apical akinesia with a severely depressed ejection fraction and an associated thrombus. An AMI with differential diagnoses of an apical aneurysm versus a pseudoaneurysm was considered, and she was transferred to our center for further evaluation. The coronary angiography revealed an occlusion in the mid-left anterior descending artery, with no other significant lesions. The magnetic resonance imaging and the computed tomography scans showed severe left ventricular dysfunction, subacute infarction, and an apical pseudoaneurysm with a fragmented thrombus. A surgical resolution was considered, but the computed tomography scans revealed severe emphysema, and the pulmonary function tests showed severe obstructive ventilatory impairment. Any type of intervention was considered high risk, and it was decided to continue with medical treatment. Nine months later, the patient is still alive and asymptomatic.