A 56-year-old man was seen in the Emergency ward because of severe dyspnea and is admitted to the medical ICU. For the past month he had felt unwell and had complained of fatigue and mild breathlessness on exertion. In the ICU he develops an arrhythmia and his condition rapidly deteriorates:

• Atrial fibrillation with rapid ventricular response (205/min)
• Occasional premature ventricular complexes
• Non-specific ST abnormalities

This patient was found to have a mass in the left lung. There was a large left pleural effusion. The echocardiogram demonstrated pericardial effusion without evidence of tamponade. The pleural fluid showed the presence of adenocarcinoma cells. It was felt that the arrhythmia was due to cardiac involvement by the carcinoma.