Commotio Cordis

Sudden death during sports are caused by

Concussion of the heart
Young athletes (Male 4 - 16 yo)
Low energy impact to chest - usually with ball - directly over ventricle - not precordium
Timing of impact must be precise (30 - m15 msec before peak T wave)
Presumed selective K+ channel activation
Immediate VF or occasional transient heart block (occasional LBBB)
Survivors all have - impressive transient ST segment elevation (V1- V3) and normal investigations including QTc
Only treatment is Early Defibrillation (and early CPR)