Blunt chest trauma producing acute myocardial infarction in a rugby player

The heart's position between the sternum and vertebral column makes it vulnerable to injury from blunt chest trauma. Myocardial contusion needs be differentiated from blunt chest trauma related coronary artery events, but this can be difficult.4 Symptoms may be wrongly attributed to traumatic chest wall pain.4 Both conditions may produce myocardial enzyme elevation, ECG abnormalities and wall motion abnormalities on echocardiography. ECG changes in blunt cardiac injury may reflect myocardial injury; q waves, ST elevation or depression, conduction abnormalities, arrhythmias or non-specific changes, such as a prolonged QT interval.5 Coronary artery dissection or occlusion following blunt chest trauma typically involves the left anterior descending artery (76%) followed by the right coronary artery (12%) and the left circumflex coronary artery (6%).1 Dramatic acceleration/deceleration forces probably cause intimai tears of the most vulnerable part of the left anterior descending artery, the junction of its proximal and mid portions.4 Other factors may include coexisting atherosclerosis with fracture of a pre-existing plaque, spasm, thrombosis and emboli.4 Sudden death following a coronary artery dissection may be misdiagnosed as commotio cordis (ventricular arrhythmia from blunt chest trauma), if the coronary artery injury is not recognised.