Principal Investigator: Barry J. Maron. Ph.D.
Institution: Minneapolis Heart Institute Foundation, Minneapolis, MN
Title: Clinical Profile of Commotio Cordis: An Under-Appreciated Cause of Sudden Cardiac Death in the Young During Sporting and Other Activities.
Abstract: Sudden cardiac death in young athletes is usually due to a variety of unsuspected congenital heart malformations. Less well recognized are those athletic field catastrophes in which cardiac arrest is produced by direct, blunt blows delivered directly to the chest by high-velocity missiles and objects such as baseballs or hockey pucks during sports activities, in the absence of identifiable morphologic injury to the sternum, ribs or heart itself (commotio cordis). To better characterize the clinical profile of this syndrome we have now assembled 69 well-characterized cases, including 34 occurring during organized competitive athletics and 35 that occurred during informal recreational sports at home, school or the playground or during other non-sporting activities. Ages ranged from 1 to 38 (mean 12) with 70% < 16 years old. The most common sports involved were youth baseball (n=39), softball (n=7), and ice hockey (n=7), but with 3 each in football and soccer and 2 each in karate and rugby. Chest blows were produced in 52 (75%) by a projectile that was part of the game itself such as baseballs or hockey pucks; the other 17 events (25%) did not involve a projectile, but rather were the result of broad surface bodily contact with the victim’s chest, such as in a collision with a teammate or a karate kick. Seven of the 69 commotio cordis victim’s (10%) survived their cardiac arrest; in 5 of these 7 survivors cardiopulmonary resuscitation by bystanders was particularly prompt (² 1 minute). Eleven of the 59 commotio cordis events (19%) occurred despite the presence of chest padding or protection, while in the other 48 victims the precordium was completely unprotected. Of note, 4 of the victims in the study group of 69 experienced modest chest blows removed from sports activities, either in playful or adversarial circumstances; each of these was convicted of criminal acts within the justice system. In conclusion, the commotio cordis syndrome: 1) accounts for an important subset of sudden deaths during sports activities, occurring in the absence of cardiovascular disease and unassociated with structural injury to the heart and chest wall; 2) is due to blunt chest blows that do not appear particularly unusual for the game or athletic activity or of sufficient magnitude to result in cardiac arrest; 3) is not uniformly fatal and about 10% survive the incident; and 4) may occur in circumstances unassociated with sports and even lead to criminal conviction due to unfamiliarity with this syndrome; and 5) appears to be due to ventricular dysrhythmia initiated by blunt chest impact at the electrically vulnerable period of repolarization. Recognition of the clinical profile of commotio cordis is critical to creating an informed public, formulating preventative measures to enhance the safety of athletic competition and other activities, and thereby increase the likelihood that cardiopulmonary resuscitation and defibrillation will be initiated promptly when these events do occur, thereby advancing the possibility of survival.
Manuscripts:
Maron, BJ, Poliac, JC, Kyle, SS: Clinical profile of commotio cordis: an underappreciated cause of sudden cardiac death in the young during sports activities. 1997 American Heart Association meeting. Circulation 1997;96(Suppl. 1):1-775.
Maron, BJ: Athlete’s Heart and Sudden Cardiac Death. In Comprehensive Cardiovascular Medicine (EJ Topol, ed.), Lippincott-Raven, Publ., Chapter 37, Philadelphia, PA, 1998, pages 1081-10095.