Traumatic rupture of a papillary muscle of the mitral valve due to blunt thoracic trauma.

Traumatic injuries of the mitral valve are rare but life threatening complications of high speed motor vehicle accidents. The physician must recognize traumatic mitral valve injuries early and arrange for immediate surgical repair, because if the papillary muscle ruptures completely, florid congestive failure and pulmonary edema develop rapidly. The signs and symptoms of traumatic mitral valve injuries vary. In general, the patient complains of chest pain and is hypotensive, dyspneic and cyanosed. He may have a bruised anterior chest wall, fractured ribs, unstable sternum and a flail chest, but extensive and severe cardiac damage from blunt trauma can occur without external evidence of chest injury. Traumatic mitral valve injuries should be suspected in any patient who has a blunt chest injury when a previously undocumented systolic murmur is discovered along the lower left sternal border or apex of the heart. The patient's deterioration, and the development of symptoms and signs of congestive heart failure support the diagnosis.