Commotio Cordis – a cause for sudden death of athletes

Commotio Cordis – a cause for sudden death of athletes

Commotio cordis is the term given to sudden arrhythmic death due to blunt chest wall trauma. Death is almost instantaneous and the victims are in ventricular fibrillation. Usually there is no structural damage to the heart or thoracic structures. Impacts which occur in the vulnerable phase of ventricular repolarization just before the peak of the electrocardiographic T wave result in ventricular fibrillation. Rapid rise in ventricular pressure due to the impact possibly causes activation of ion channels by mechano-electric coupling. This causes a ventricular ectopic beat which triggers ventricular fibrillation. Commotio cordis has to be differentiated from contusio cordis in which there is direct myocardial tissue damage and damage to overlying structures of the chest due to a high velocity projectile impact. Generally commotio cordis is caused by impact by a ball with a dense solid core like baseball. Balls with non-solid core tend to collapse on contact and absorb most of the impact energy so that commotio cordis is quite rare with impact by an air filled soccer ball [1].

Commotio cordis is more likely to occur in younger individuals, possibly because of greater transmission of the impact energy by a compliant chest wall. 95% of cases occur in adolescent males, with a mean age of 14 years [2]. Poor survival of commotio cordis of 16% was reported in 2002 from US Commotio Cordis Registry. In the same report, 28% of the participants were wearing commercially available chest barriers. Of these in 7 the projectile had made direct contact with the protective padding and two were with a baseball specifically designed to reduce risk [3]. Improved survival has been reported in later publications. Overall survival in a report from the same registry in 2013 was 28%. The survival had improved to 58% during the last 6 year period of the report, which was on 10% in the initial part of the study between 1970-1993. As expected, higher survival rates were there in resuscitation within 3 minutes (40%) vs 4% for resuscitation after 3 minutes. Use of on-site automated external defibrillator was also protective [4].

In an experimental study using baseballs, the threshold for causing ventricular fibrillation was between 40-48 km/h. Peak incidence was at impacts at 64 km/h. The likelihood of ventricular fibrillation decreased at velocities above 80 km/h [1]. This was in concordance with the clinical scenario of commotio cordis in youth baseball with estimated velocities in the range of 48 to 80 km/h.

All resuscitated victims should undergo thorough evaluation for underlying cardiac pathology and susceptibility to arrhythmias. Though they may resume training and competition later if no underlying cardiac abnormality is identified, certain riders have to be considered. There is some animal data for individual susceptibility to commotio cordis. It would be prudent to avoid sports that involve chest wall impact. Maturation of chest wall with age can also reduce risk of recurrent commotio cordis [2].

According the FIFA Sudden Death Registry of sudden death in worldwide football from 2014 to 2018, a total of 617 players with sudden death were reported from 67 countries, of which 23% survived [5]. This prospective study reported that traumatic sudden death including commotio cordis occurred infrequently (6%).

References

  1. Madias C, Maron BJ, Alsheikh-Ali AA, Estes Iii NA, Link MS. Commotio cordis. Indian Pacing Electrophysiol J. 2007 Oct 22;7(4):235-45.
  2. Link MS, Estes NA 3rd, Maron BJ; American Heart Association Electrocardiography and Arrhythmias Committee of Council on Clinical Cardiology, Council on Cardiovascular Disease in Young, Council on Cardiovascular and Stroke Nursing, Council on Functional Genomics and Translational Biology, and American College of Cardiology. Eligibility and Disqualification Recommendations for Competitive Athletes With Cardiovascular Abnormalities: Task Force 13: Commotio Cordis: A Scientific Statement From the American Heart Association and American College of Cardiology. Circulation. 2015 Dec 1;132(22):e339-42.
  3. Maron BJ, Gohman TE, Kyle SB, Estes NA 3rd, Link MS. Clinical profile and spectrum of commotio cordis. JAMA. 2002 Mar 6;287(9):1142-6.
  4. Maron BJ, Haas TS, Ahluwalia A, Garberich RF, Estes NA 3rd, Link MS. Increasing survival rate from commotio cordis. Heart Rhythm. 2013 Feb;10(2):219-23.
  5. Egger F, Scharhag J, Kästner A, Dvořák J, Bohm P, Meyer T. FIFA Sudden Death Registry (FIFA-SDR): a prospective, observational study of sudden death in worldwide football from 2014 to 2018. Br J Sports Med. 2020 Dec 23:bjsports-2020-102368.