We describe 2 men, ages 69 and 49 years, who experienced fatal rupture of pulmonary infarcts. Both patients had documented prior thromboembolic events and subsequently had abrupt deterioration in cardiorespiratory function. Autopsies showed massive unilateral hemothorax in both patients. Rupture of a pulmonary infarct may occur spontaneously or iatrogenically due to aggressive anticoagulation. This may be difficult to distinguish from secondary hemothorax with an intact pleura, but rupture typically has a considerably more rapid clinical evolution. Treatment should include immediate withdrawal of thrombolytic or anticoagulant medications and evacuation of the pleural space. Surgical intervention can be considered, although the utility of that approach must await prospective trials.