Concealed metastatic lung carcinoma presenting as acute coronary syndrome with progressive conduction abnormalities.

A 70-year-old diabetic woman with recent onset of cough was admitted to the emergency room for acute chest pain with evidence of T-wave abnormalities in the V2 through V6, L1, and aVL leads (Figure 1A). Her coronary arteries were angiographically normal, and her troponin I was elevated at 0.3 μg/L. Two-dimensional echocardiography revealed a hypertrophic left ventricle without kinetic abnormalities. Three weeks later, the patient was readmitted for chest pain and a complete left bundle-branch block on 12-lead ECG (Figure 1B) with a peak troponin I of 0.429 μg/L. To exclude a myocarditis, a cardiac magnetic resonance (CMR) was performed. On early scout images, diffuse multiple nodules with irregular epicardial borders were evident (Figure 2A–2C), which were also present on CMR T1 cine balanced images, indicating an irregular tissue composition (Movies I and II in the online-only Data Supplement). A moderate pericardial effusion was also detected. On T2-weighted images, the nodules presented a signal intensity higher than skeletal muscle (Figure 3A). First-pass contrast …