Spontaneous pneumothorax is a common surgical disease that is a surgical emergency. It can be divided into primary (caused by microscopic blebs <1 cm in diameter) and secondary (asthmatic, catamenial, neonatal, caused by emphysematic bullae or chronic respiratory obstruction) varieties. This surgical entity has been closely associated to a variety of electrocardiographic (ECG) changes, which are pathophysiologically explained by spatial changes in the anatomical structure of the mediastinum caused by increased hemithoracic pressure. Several reports on ECG variations due to pneumothorax that masquerades as myocardial ischemia have been previously recorded. However, when the underlying disease involves two pathological entities, in this case pneumothorax and myocardial infarction, time limits can be pressing. Herein, we describe an interesting case of a patient who presented with left secondary spontaneous pneumothorax associated with acute myocardial infarction. It is an intriguing and rarely encountered case in which the patient's anamnesis can easily mislead the clinician and valuable time can be wasted.