💔 Commotio cordis is a rare but catastrophic event where a blunt chest impact triggers ventricular fibrillation (VF) — even in a structurally normal heart.
It occurs when the impact coincides with a 20 ms “vulnerable window” on the upslope of the T wave, akin to an R-on-T phenomenon.
Immediate defibrillation is the only effective treatment — survival falls by 10% for every minute delay ⚡.
⚕️ Aetiology
- Blunt chest trauma: Sudden, focused impact over the precordium from small, hard projectiles — e.g. baseballs, hockey pucks, cricket balls, lacrosse shots.
- Mechanism: Mechanical energy triggers ventricular depolarisation during the repolarisation phase (T wave), precipitating VF without structural injury.
- Demographics: Predominantly young male athletes (ages 8–18) in competitive sports, often wearing inadequate chest protection.
⚡ Clinical Presentation
- Instantaneous collapse following chest impact.
- No palpable pulse or cardiac output — typically due to VF.
- Transient myoclonic jerks or seizure-like activity may be observed due to cerebral hypoxia.
- Importantly: there is no underlying cardiac structural damage (normal myocardium at autopsy).
🚑 Management
- Immediate defibrillation: Rapid use of an AED is lifesaving — early shocks restore rhythm in over 50% of witnessed cases.
- CPR: Begin chest compressions immediately while awaiting defibrillation. Maintain oxygenation and circulation.
- Post-resuscitation care: Continuous ECG monitoring, echocardiography to exclude occult structural disease, and supportive intensive care.
🛡️ Prevention
- Protective equipment: Improved chest protectors in youth sports (e.g. baseball, lacrosse) to dissipate focal impact energy.
- Environmental safety: Ensure AEDs and trained responders are present at sports facilities and schools.
- Education: Prompt recognition and action by coaches, parents, and referees saves lives — “Check, Call, Compress, Shock.”
📚 References
🧠 Teaching tip:
Commotio cordis = “concussion of the heart.” It’s electrical, not structural — a timing-dependent VF.
If the blow lands on the upstroke of the T wave, it’s fatal without defibrillation.
If it lands milliseconds earlier or later, nothing happens. ⏱️⚡
