BACKGROUND: Left ventricular noncompaction (LVNC) is a distinct cardiac phenotype characterized by prominent left ventricular trabeculae and deep intertrabecular recesses. It results in thickened myocardium with two layers consisting of non-compacted myocardium and a thin, compacted layer of myocardium. LVNC is a genetic condition associated with various cardiomyopathies, congenital heart disease, and environmental factors. CASE PRESENTATION: A 60-year-old Afroamerican male with a past medical history of hypertension and chronic kidney disease stage 3a presented to the emergency department (ED) with sudden-onset abdominal pain and associated symptoms of nausea, vomiting, and diarrhea. The patient was provided antiemetics, antihypertensives, and pain control in the ED. An abdominal x-ray showed the small bowel with multiple fluid levels concerning for obstruction. Contrast-enhanced computed tomography of the abdomen showed a wedge-shaped attenuation in the lower pole of the right kidney concerning for infarction but negative for obstruction. There was also a nonocclusive thrombus in the superior mesenteric artery. A transthoracic echocardiogram (TTE) showed a newly reduced left ventricular ejection fraction of 20-25%, moderate dilatation of the left ventricle, and severe global hypokinesis, but did not reveal any thrombus. Cardiology was consulted and recommended a transesophageal echocardiogram (TEE) along with lifelong anticoagulation with apixaban. The TEE revealed a new finding of LVNC without thrombus. The patient underwent a left cardiac catheterization which showed no significant obstructive coronary artery disease. He was discharged on guideline-directed medical therapy (GDMT). Unfortunately, the patient was noncompliant with his GDMT and anticoagulation regimen. He presented approximately six weeks later with right hemiparesis. A repeat TTE showed a large thrombus in the left ventricle. The patient remained aphasic with right hemiparesis without significant recovery before discharge. CONCLUSION: This case highlights a rare cause of heart failure and catastrophic thromboembolism: noncompaction cardiomyopathy. This case is a prime example and reminder of the potential impact of LVNC on patient morbidity and should encourage medical providers to be conscious of this anomaly and its potential for severe clinical consequences.