Question

• Do safety balls decrease the incidence of sudden cardiac death due to commotio cordis in otherwise healthy adolescents?

Clinical Bottom Lines

1. Commotio cordis is a known etiology of sudden cardiac death in young athletes and the incidence is thought to be underestimated.¹
2. The mortality rate of commotio cordis is approximately 85%, therefore, prevention may greatly affect the incidence of commotio cordis.¹
3. Baseball blows are the leading cause of commotio cordis.³
4. There may be a direct relationship to increasing ball stiffness and incidence of ventricular fibrillation and death.²

Summary of Key Evidence

1. Swine were randomized to receive chest blows by 1 of 4 balls (of increasing ball stiffness) at 40 mph, three impacts each.²
2. Animals experiencing ventricular fibrillation were defibrillated, and if stable by ECG, left ventricular function, and blood pressure, and were given additional blows.
3. There was a direct, linear relationship between baseball stiffness and incidence of ventricular fibrillation in swine models (correlation coefficient 0.94).
4. The incidence of VF in regulation youth baseballs was 69% compared to 9% in softballs in swine models.

Additional Comments

• Elasticity may increase incidence of more common injuries.
• Safety balls still produce VF.
• Experiment evaluating safety balls at 95mph showed no change in VF incidence.
• Although under reported, the incidence of commotio cordis is most likely very low nevertheless. Preventative measures may not translate practically to saved lives.
• Availability of CPR trained coaches/referees, as well as on site AED's, may be more effective at reducing sudden cardiac death in these patients.
  

Citation

1. Maron BJ. Sudden death in young athletes. N Engl J Med 2003:349:1064-75.
2. Link MS, Maron BJ, Wang PJ, et al. Reduced risk of sudden death from chest wall blows (commotio cordis) with safety baseballs. Pediatrics 2002;109:873-7.
3. 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. Journal of Cardiovascular Electrophysiology 1999;10:114-20.
4. Weinstock J, Maron BJ, Song C, Mane P, Estes M. Failure of Commercially Available Chest Wall Protectors to Prevent Sudden Cardiac Death Induced by Chest Wall Blows in an Experimental Model of Commotio Cordis. Pediatrics 2005;117:e1-7.

CAT Author: Peter Aziz, MD

CAT Appraisers: Robert Schumacher, MD

Date appraised: April 5, 2006