A patient with lung squamous cell carcinoma presenting with severe cardiac dysfunction similar to dilated cardiomyopathy with left bundle branch block induced by myocardial metastasis.

A patient with severe cardiac dysfunction similar to dilated cardiomyopathy expired because of lung squamous cell carcinoma. He was admitted with respiratory failure and was diagnosed with congestive heart failure due to dilated cardiomyopathy based on the chest X-ray, electrocardiography, echocardiography, and coronary angiography. Chest computed tomography showed a mass shadow in the right lower lobe, and the patient was diagnosed with lung squamous cell carcinoma by bronchoscopy. The patient expired, and the autopsy revealed that a myocardial metastasis disrupted the cardiac-conduction system without dilated cardiomyopathy in myocytes. Left bundle branch block caused by myocardial metastasis presumably induced left cardiac dysfunction.