Pericardial tamponade from blunt cardiac injury is rare but life threatening, and requires immediate pericardiocentesis to avoid circulatory collapse Any patient with suspected blunt cardiac injury who is hemodynamically unstable or has arrhythmias should undergo echocardiography and be admitted to the intensive care unit All patients with suspected blunt cardiac injury need close follow-up Current Evidence Cardiac injury in blunt thoracic trauma is rare In one study of 1,288 patients with blunt thoracic trauma, only 60 (4.6%) had a blunt cardiac injury, though other smaller studies reported higher incidence Myocardial contusion, ventricular or atrial rupture, and valvular disruption are considered blunt cardiac injuries Myocardial contusion is the most common blunt cardiac injury, far outnumbering lacerations Contusions are usually self-limited; rare complications include arrhythmia, congestive heart failure, and shock Also rare is commotio cordis: cardiac arrest following a single, isolated, forceful precordial blow Prompt cardiopulmonary resuscitation/defibrillation is the only identifiable factor associated with a favorable outcome after commotio cordis Cardiac rupture is the most common cause of death in blunt cardiac trauma The majority of these patients never reach a hospital because they die at the scene The right ventricle is the chamber most commonly ruptured because of its location directly beneath the sternum Septal rupture can also occur, with the condition of the patient correlating with the size of the rupture Patients with cardiac rupture may present with cardiac tamponade, demonstrating one or all the components of Beck triad (jugular venous distention, low blood pressure, and muffled heart tones) Patients with valvular injury may present in congestive heart failure with a new regurgitation murmur Coronary artery injury is rare but should be considered in patients with electrocardiogram (EKG) changes consistent with ischemia following blunt thoracic trauma Pericardial tamponade may also occur when there is injury to the myocardium and blood accumulates in the pericardial sac Because of the nondistensible pericardium, pressure is exerted on the heart Cardiac output decreases secondary to a decrease in venous return and ventricular stroke volume The body will initially compensate with an increase in the pulse rate and peripheral vascular resistance As the pressure within the pericardial sac increases, the systolic blood