Electrocardiogram Changes Suggestive of Coronary Artery Disease in Pneumothorax

Spontaneous pneumothorax is an important consideration in the differential diagnosis of acute chest pain. Unless evidence of pneumothorax is sought carefully, this diagnosis may be missed on physical examination. In recent months, we have seen several patients with pneumothorax in whom complaints of chest pain and dyspnea, coupled with an abnormal electrocardiogram, raised the diagnostic possibility of myocardial infarction. We wish to draw attention to the ECG abnormalities associated with pneumothorax and to the useful sign of normalization of the ECG when the patient is in the sitting position. Patient Summaries Patient 1 (141-75-02). —A 20-year-old man experienced, during exertion, the sudden onset of nonradiating pain in the left anterior portion of the chest, associated with moderate dyspnea and sweating. On physical examination, he was a thin, muscular man in moderate respiratory distress with a blood pressure of 140/80 mm Hg; pulse rate, 90 beats per minute; respirations, 30/min; and