ECG changes associated with spontaneous left-sided pneumothorax.

A patient with chronic obstructive pulmonary disease had a 100% pneumothorax on the left side associated with marked ECG changes. The changes occurring in this situation can be confusing. Because of the high prevalence of coronary heart disease in patients presenting with left-sided chest pain, an ECG usually is obtained to rule out acute myocardial infarction, in many instances even before history taking, physical examination, or chest x-ray study is done. Therefore, familiarity with the ECG manifestations of left-sided penumothorax is necessary to avoid delay in establishing the diagnosis and in beginning therapy.