Infarction-Like Electrocardiographic Changes Due to a Myocardial Metastasis From a Primary Lung Cancer
A 69-year-old man (a heavy smoker) presented with chest pain and dyspnea that he had experienced for several days. The initial ECG revealed ST-segment elevations in the leads V2 through V5, suggesting an acute myocardial infarction (Figure 1A). Laboratory tests showed normal levels of creatine kinase and troponin T, but an elevated pro-brain natriuretic peptide (1895 ng/L; normal value for adult males is <227 ng/L). Chest radiography revealed a tumorous mass in the right upper lobe. A computed tomography scan demonstrated a lung tumor occluding the right main bronchus. In addition, a 3.7-cm, hypodense lesion was seen in the apical near-right ventricular myocardium, consistent with a metastasis (Figure 1A). Echocardiography confirmed a right ventricular mass filling the apex and one third of the right ventricle (Figure 2). Left ventricular function was unimpaired. The biplane ejection fraction was 65% (fractional shortening: 47%; left ventricular end-diastolic volume: 132 mL; left ventricular end-systolic volume: 29 mL; interventricular septum: 1.2 cm, akinetic; left ventricular posterior wall: 1.1 cm, contraction normal).
By transbronchial biopsy, a squamous cell carcinoma was diagnosed. The respiratory symptoms resolved after an Ultraflex stent had been placed in the right main bronchus.
Three months after onset of chemotherapy with carboplatin and gemcitabine, the patient’s cancer progressed, with growth of the myocardial metastasis. In ECG, more pronounced ST-segment elevations and new elevations in leads V1 and V6 were detected (Figure 1B).
Chest pain and infarction-like ECG changes were associated with tumor in this case. Usually, myocardial metastases remain clinically unapparent and are only discovered at autopsy. Although acute myocardial infarction is the most frequent cause of ST-segment elevations, the possibility of a myocardial metastasis should be considered when electrocardiographic changes are seen in patients with malignancies.
↵*The first 2 authors contributed equally to this work.
The online-only Data Supplement, consisting of a movie, is available with this article at http://circ.ahajournals.org/cgi/content/full/115/10/e320/DC1.