This will be the first prospective, randomized clinical study ever performed on penetrating cardiac injuries in the world literature. A group of patients with penetrating chest injuries will present haemodynamically stable, with blood in the pericardial sac diagnosed on ultrasound. The accepted international management of what is termed; "the stable haemopericardium" has been a median sternotomy. In our experience in Cape Town, when a median sternotomy is performed in these cases, any cardiac injury if present has already sealed or there is no cardiac injury. We feel that these patients should be managed with a much smaller and simpler operation that does not require admission to the intensive care unit post-operatively and this is merely drainage of the blood from around the pericardial sac via a subxyphoid window (SXW).