Criteria for commotio cordis:
(1) witnessed event
(2) blunt, non-penetrating blow to the chest, which may seem relatively innocuous
(3) cardiac arrest follows immediately or within moments
(4) no gross structural damage to the heart, chest wall or internal organs
(5) patients often young and healthy, usually males
(6) ventricular tachyarrhythmias identified if an ECG is available
Precipitating events:
(1) flying object: baseball, hockey, football, soccer, lacrosse, basketball, iceball
(2) human contact or bodily collisions: karate, boxing, football, rugby
(3) traumatic accident: traffic accidents, falls, impact on play equipment
Mechanism: The impact occurs at an electrically vulnerable phase of the cardiac cycle (during early ventricular repolarization; 15-30 milliseconds before the peak of the T wave).
