A case of double cancers with myocardial metastasis mimicking acute myocardial infarction both on an electrocardiogram and on Tc-99m-MIBI myocardial SPECT

Case report: Persistent ST-segment elevation due to cardiac metastasis from lung cancer

Patients with secondary cardiac cancer occasionally show ST segment elevation that mimics acute coronary syndrome despite the absence of coronary artery occlusion. We herein describe a rare case of secondary cardiac cancer that presented with ST-segment elevation. An 82-year-old Chinese man was admitted to the hospital with chest discomfort. Electrocardiography (ECG) showed ST segment elevation in the precordial leads and low-voltage QRS complexes in limb leads without the development of Q waves. Unexpectedly, emergency coronary angiography showed no significant stenosis of the coronary arteries. However, fortunately, transthoracic echocardiography (TTE) revealed massive pericardial effusion and a mass at the apex of the ventricular myocardium. Coincidentally, contrast-enhanced chest computed tomography showed primary lung cancer in the left lower lobe, pericardial effusion, and myocardial metastasis at the ventricular apex. The pericardiac fluid contained blood with significantly increased CEA levels and exfoliated tumor cells. The lung histopathological report suggested squamous cell carcinoma. Two months later, the patient died. These findings suggested that the persistent ST-segment without the development of Q waves was associated with ventricular invasion by primary lung cancer and may indicate a poor prognosis. In conclusion, physicians should be aware of persistent ST-segment elevation mimicking myocardial infarction due to cardiac metastasis with a poor prognosis.

Noninfiltrating Adenocarcinoma of the Lung Causing ST-Segment Elevation

ST-segment-elevation myocardial infarction is a leading cause of cardiovascular morbidity and death. We describe the case of a 51-year-old woman with advanced adenocarcinoma of the lung who presented with ST-segment elevation in the presence of an extracardiac lung mass but no objective evidence of myocardial ischemia or pericardial involvement. After the patient died of hypoxic respiratory failure, autopsy findings confirmed normal-appearing pericardium and myocardium, and mild-to-moderate atherosclerosis in the coronary arteries. A 4.5 × 4-cm extracardiac left hilar lung mass was confirmed to be poorly differentiated adenocarcinoma of the lung adjacent to the myocardium. The persistent current of injury that had been detected electrocardiographically was thought to occur from direct myocardial compression. ST-segment elevations secondary to direct mass contact on the myocardium should be considered in patients who have a malignancy and ST-segment elevation.

Myocardial metastases from renal cell carcinoma mimicking ischemia on myocardial perfusion scintigraphy

A 60-year-old man with history of metastatic renal cell carcinoma and atypical chest pain was referred for dipyridamole Tc-tetrofosmin perfusion scintigraphy (MPS). Two years earlier, the patient was noted to have myocardial metastases on cardiac MRI. On the MPS, perfusion defects were present at stress in multiple vascular territories; resting myocardial uptake was homogeneous. These findings suggested multivessel atherosclerotic heart disease. In fact, retrospective rigid fusion with prior chest CT and cardiac MRI demonstrated that the reversible perfusion defects corresponded to metastatic deposits in the myocardium. This unusual case illustrates how myocardial metastases can mimic ischemia on MPS.

Intracardiac Extension of Lung Cancer Demonstrated on PET Scanning

Intracardiac tumors are unusual and can originate within the heart or spread from other sites. This is a report of a patient who presented with a TIA, and during the subsequent stroke workup, a right hilar nonsmall cell lung carcinoma was discovered. The tumor had extended into the left atrium through a pulmonary vein. The hilar tumor as well as intracardiac extension were demonstrated by PET scanning using FDG.