Cardiac injuries associated with a penetrating thoracic injury are not frequently encountered. The usual course is characterized by massive haemorrhage, cardiac tamponade and an entering wound in the cardiac area. Diagnostic problems arise if these clinical syndromes are absent. In the course of two years at the authors' department two cases of tangential cardiac lesions in the posterior left ventricular wall without penetration into the heart without massive haemorrhage and tamponade were absent as haemorrhage of the pericardial lesion into the pleural space occurred. It is not without interest that the entry wound was far away from the heart and the cardiac lesions were detected during surgical intervention made on account of other symptoms.