Cardiac concussion (commotio cordis)
Blunt chest trauma in pediatric patients can result in various injuries to the myocardium. Cardiac concussion (commotio cordis) is seen in patients in whom the precordium has been struck with relatively little force at a vulnerable period of the cardiac cycle. These patients have no predisposing cardiac problems, and autopsy reveals no evidence of heart damage. The usual clinical presentation is that of immediate collapse secondary to a lethal arrhythmia. Prevention is the cornerstone of potentially decreasing the incidence with the aid of safety equipment and, possibly, immediate defibrillation.
Un traumatisme contondant au thorax chez les patients pédiatriques peut causer diverses lésions au myocarde. On constate une commotion cardiaque (commotio cordis) chez les patients dont la région précordiale a subi un choc relativement faible à un moment vulnérable du cycle cardiaque. Ces patients n'ont aucun problème cardiaque prédisposant et l'autopsie ne révèle aucun signe de dommages cardiaques. Sur le plan clinique, le phénomène se manifeste habituellement par un effondrement immédiat secondaire à une arythmie mortelle. La prévention constitue la pierre angulaire de la réduction possible de l'incidence au moyen de matériel de sécurité, et peut-être, d'une défibrillation immédiate.
See also Commentary
Although trauma, in general, is the leading cause of mortality in children worldwide1,2 clinically significant isolated blunt chest trauma in children is rare. Chest injuries range from benign chest wall contusions to life-threatening conditions such as cardiac rupture, coronary artery laceration, valvular disruption, cardiac contusion and cardiac concussion (commotio cordis). Of these, the most distressing may be cardiac concussion because it occurs with relatively little force, its victims have normal underlying cardiac anatomy, and because there is no appreciable structural heart damage, even at autopsy.3,4 Emergency physicians, particularly those interested in injury prevention, should be familiar with cardiac concussion because its mortality rate is as high as 85% and because it is often preventable.5
Minneapolis' Commotio Cordis registry, established in 1998, has documented only 128 cases in the United States, but because of rarity and underreporting, the true incidence is unknown.5-9 Most reported cases were the result of being struck in the chest with a baseball,7,8,10 but cardiac concussion has occurred in ice hockey, lacrosse, softball, soccer, karate and football,7,11-14 and may even occur after non-accidental trauma.15-19 Nearly two-thirds of cases involve children <16 years of age.12,20,21 The oldest patient we identified was 20 years old, and the youngest was a 7-week infant whose father, frustrated with the infant's crying, fatally struck his child on the chest.15
The majority of patients with commotio cordis lose consciousness and collapse immediately, after a precordial injury.8,12,20 Occasional reports describe a lucid interval in which the child is struck in the chest, falls to the ground, and then stands up briefly only to promptly collapse again.12,20 If a monitor or defibrillator is immediately available, it will most likely reveal ventricular fibrillation.12,20 Cardiac concussion is not a delayed phenomenon.
Cardiac concussion occurs only when specific conditions are met. These involve force, exact timing and location of impact, and a compliant chest wall. Impact force must be sufficient to induce a ventricular dysrhythmia, but not so great as to result in structural myocardial damage.22 In experimental animal studies and retrospective case reviews, the ideal circumstances arise when a baseball strikes the chest wall at about 65 k/h, approximately the pitch speed achieved by 11- and 12-year-old boys who play ball at the competitive level.8,23 Force transmission is directly related to the hardness of the object, and in experimental studies the use of softer baseballs decreases the rate of ventricular fibrillation induction from 69% to 11%.8 Ventricular fibrillation is most common when the injury occurs directly to the chest wall overlying the heart.21,24 Attempts to refine this localization have not been convincing.22
In animal models, induced cardiac concussion has led to a variety of electrocardiographic findings, including complete heart block, bundle branch blocks, ST-segment changes and atrial fibrillation.20,25-27 Ventricular fibrillation is most likely when the impact occurs just prior to the peak of the T-wave.20 A compliant chest wall, as seen in most children, increases the susceptibility to cardiac concussion.28,29
Given the rarity of this condition, studies of prevention and treatment may not be feasible; however, based on our current understanding, various safety measures have been recommended, including softer, age-appropriate baseballs7,8,20,30 and chest wall protectors.7,8,12,20,21,30,31 Ventricular fibrillation management consists of immediate basic life support and prompt defibrillation.7,8,20,21,30 In 2001, automated external defibrillators (AEDs) specifically modified to provide appropriate voltages (approximately one-third) to children ¾8 years of age or <55 lb (25 kg) became available (). The paddles are positioned differently (i.e., anterior/posterior placement) for these patients. However, the best way to implement public access defibrillation programs in anticipation of rare events such as cardiac concussion remains controversial.32,33
Cardiac concussion is an uncommon but devastating result of seemingly insignificant chest trauma. Most documented cases have occurred in children and adolescents during sporting events such as baseball and ice hockey. The terminal event is usually ventricular fibrillation that results in death if not promptly treated with defibrillation. Emergency physicians can play a major role in awareness and prevention campaigns and in evolving public access defibrillation programs.
- Committee on Trauma Research (US). Injury in America: a continuing public health problem. Committee on Trauma Research, Commission on Life Sciences, National Research Council and the Institute of Medicine, Washington, DC: National Academy Press; 1985.
- World Health Statistical Annual, 1994. Geneva, Switzerland: WHO; 1994.
- McCrory P. Commotio cordis. Br J Sports Med 2002;36:236-7.
- Maron BJ, Link MS, Wang PJ, Estes NA 3rd. Clinical profile of commotio cordis: an under appreciated cause of sudden death in the young during sports and other activities. J Cardiovasc Electrophysiol 1999;10(1):114-20.
- Maron BJ, Gohman TE, Kyle SB, Estes NA 3rd, Link MS. Clinical profile and spectrum of commotio cordis. JAMA 2002;287(9):1142-6.
- Link MS, Wang PJ, Estes NA 3rd. Ventricular arrhythmias in the athlete. Curr Opin Cardiol 2001;16(1):30-9.
- Vincent GM, McPeak H. Commotio cordis: a deadly consequence of chest trauma. Physician Sportsmed 2000;28(11). Available:  (accessed 2004 Oct 25).
- Link MS, Maron BJ, Wang PJ, Pandian NG, VanderBrink BA, Estes NA 3rd. Reduced risk of sudden death from chest wall blows (commotio cordis) with safety baseballs. Pediatrics 2002;109(5):873-7.
- Perron AD, Brady WJ, Erling BF. Commotio cordis: an underappreciated cause of sudden cardiac death in young patients: assessment and management in the ED. Am J Emerg Med 2001;19(5):406-9.
- Abrunzo TJ. Commotio cordis: the single, most common cause of traumatic death in youth baseball. Am J Dis Child 1991;145(11):1279-82.
- Kaplan JA, Karofsky PS, Volturo GA. Commotio cordis in two amateur ice hockey players despite the use of commercial chest protectors: case reports. J Trauma 1993;34(1):151-3.
- Maron BJ, Poliac LC, Kaplan JA, Mueller FO. Blunt impact to the chest leading to sudden death from cardiac arrest during sports activities. N Engl J Med 1995;333(6):337-42.
- Curfman GD. Fatal impact -- concussion of the heart. N Engl J Med 1998;338(25):1841-3.
- Luckstead EF, Patel DR. Catastrophic pediatric sports injuries. Pediatr Clin North Am 2002;49(3):581-91.
- Baker AM, Craig BR, Lonergan GJ. Homicidal commotio cordis: the final blow in a battered infant. Child Abuse Negl 2003;27(1):125-30.
- Denton JS, Filkins JA, Stephenson D. Criminal consequences of commotio cordis. Am J Cardiol 2002;90(10):1181-2.
- Maron BJ, Mitten MJ, Greene Burnett C. Criminal consequences of commotio cordis. Am J Cardiol 2002;89(2):210-3.
- Denton JS, Kalelkar MB. Homicidal commotion cordis in two children. J Forensic Sci 2000;45(3):734-5.
- Boglioli LR, Taff ML, Harleman G. Child homicide caused by commotio cordis. Pediatr Cardiol 1998;19:436-8.
- Link MS, Wang PJ, Pandian NG, Bharati S, Udelson JE, Lee MY, et al. An experimental model of sudden death due to low-energy chest-wall impact (commotio cordis) N Engl J Med 1998;338(25):1805-11.
- Link MS, Maron BJ, VanderBrink BA, Takeuchi M, Pandian NG, Wang PJ, et al. Impact directly over the cardiac silhouette is necessary to produce ventricular fibrillation in an experimental model of commotio cordis. J Am Coll Cardiol 2001;37(2):649-54.
- Liedtke AJ, Allen RP, Ellis SH. Effects of blunt cardiac trauma on coronary vasoconstriction, perfusion, myocardial mechanics, and metabolism. J Trauma 1980; 20:777-85.
- Link MS, Maron BJ, Wang PJ, VanderBrink BA, Zhu W, Estes NA 3rd. Upper and lower limits of vulnerability to sudden arrhythmic death with chest-wall impact (commotio cordis). J Am Coll Cardiol 2003;41(1):99-104.
- Chen RL, Penny DJ, Greve G, Lab MJ. Stretch-induced regional mechanoelectric dispersion and arrhythmia in the right ventricle of anesthetized lambs. Am J Physiol Heart Circ Physiol 2004;286(3):H1008-14.
- Link MS. Commotio cordis: sudden death due to chest wall impact in sports. Heart 1999;81(2):109-10.
- Futterman LG, Lemberg L. Commotio cordis: sudden cardiac death in athletes. Am J Crit Care 1999;8(4):270-2.
- Kohl P, Nesbitt AD, Cooper PJ, Lei M. Sudden cardiac death by commotio cordis: role of mechano-electric feedback. Cardiovasc Res 2001;50(2):280-9.
- Bir CA, Viano DC. Biomechanical predictor of commotio cordis in high-speed chest impact. J Trauma 1999;47(3):468-73.
- Kroell CK, Allen S, Warner CY. Inter-relationship of velocity and chest compression in blunt thoracic impact to swines. Society of Automotive Engineers (SAE) tech paper no 861881. Proceedings of the 30th Stapp Car Crash Conference, Warrendale, Pa. SAE, 1986: 99.
- Lateef F. Commotio cordis: an underappreciated cause of sudden death in athletes. Sport Med 2000;30(4):301-8.
- Viano DC, Bir CA, Cheney AK, Janda DH. Prevention of commotion cordis in baseball: an evaluation of chest protectors. J Trauma 2000;19(6):1023-8.
- Strasburger JF, Maron BJ. Images in clinical medicine. Commotio cordis. N Engl J Med 2002;347(16):1248.
- Link MS, Maron BJ, Stickney RE, Vanderbrink BA, Zhu W, Pandian NG, et al. Automated external defibrillator arrhythmia detection in a model of cardiac arrest due to commotio cordis. J Cardiovasc Electrophysiol 2003;14(1):83-7.