Cardiac injury occurs in about 20-30% of major chest traumas; 80% of penetrating cardiac wounds are fatal; the survival rate is related to the mechanism of injury (whether by stab wound or gunshot wound), the extent of injury, the need for emergency room thoracotomy for resuscitation, and the presence of cardiac tamponade. The right ventricle and atrium are the most commonly involved cardiac chambers. We present a case of 63-year-old male patient who presented with a systolic murmur after a chest wall stab wound. Transthoracic echocardiogram revealed a small pericardial effusion and laceration of the interventricular septum. Cardiac catheterization revealed a moderate increase in mean pulmonary artery pressure and a moderate left to right shunt, due to interventricular defect which was closed percutaneously. The presented case is very unusual: the clinical picture was very poor because of the spontaneous closure of the wound, the absence of signs of cardiac tamponade, and the moderate size of the defect. We emphasize the role of echocardiography in the anatomic and functional evaluation of such lesions.