The most important factor that influences the outcome of penetrating cardiac injuries is:

C. Coronary artery injury.

DISCUSSION: Multiple studies in the literature confirm that injuries to the coronary arteries are the most important factor in determining outcome after a penetrating cardiac injury. Tangential injuries are the least serious. Injury to a single chamber— even if comminuted—or to multiple chambers is less likely to be fatal than are injuries that involve a major coronary artery.