Makindo Medical Notes

💔 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

• Link MS et al. Commotio Cordis. N Engl J Med 2010;362:917–927.
• StatPearls: Commotio Cordis

🧠 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. ⏱️⚡