Commotio Cordis

Ever heard of the Damar Hamlin incident back in 2023? A 24-year-old Buffalo Bills safety, Damar Hamlin was struck directly in the chest by a Cincinnati Bengals player during a January 2nd game, causing him to collapse onto the field. The cause? Commotio cordis, an extremely rare condition that results from direct blunt-force trauma to the chest during a specific period of the cardiac cycle. It induces cardiac arrest and ventricular fibrillation upon collision. In this article, we break down the specifics of commotio cordis.

The Cardiac Cycle and Commotio Cordis:

Typically, the heart has a standard electrical rhythm that maintains a consistent 60-100 bpm. This involves changes in polarity reflected in an ECG reading listed below. If an athlete with commotio cordis experiences blunt force trauma of more than 40 mph– especially from spherical objects like baseballs– to the left side of their chest during the upslope of the T-wave (a window of roughly 20-40 milliseconds), then the upper ventricles fail to repolarize.

Because of their rigid and dense structure on top of their tendency to direct force to a singular point, objects such as baseballs and softballs have higher rates of causing commotio cordis.

As a result, the heart goes into ventricular fibrillation, a process in which the chambers of the heart quiver, instead of fully contracting. This leads to failure in properly circulating blood, which ultimately results in loss of consciousness and possible death if quick action is not taken.

Symptoms of Commotio Cordis:

Like other forms of cardiac arrest, commotio cordis triggers a series of cascading events that lead to a disruption in blood flow. Below are some symptoms of commotio cordis:

• Loss of consciousness

• No pulse

• No respiration

• Athlete is not responsive

• Sudden collapse despite being active for several seconds after the blow

With this in mind, commotio cordis can very quickly become fatal. In recent years, the survival rate for commotio cordis has risen to roughly 59% in patients who received cardiopulmonary resuscitation (CPR). In previous years, the survival rate with the use of an automated external defibrillator (AED) was roughly 15%. In addition, those who received treatment within the first 3 minutes saw a survival rate of 25% compared to 10-15% of those who received treatment after that timeframe.

Treatment for Commotio Cordis and Effects:

At its core, commotio cordis is extremely similar to sudden cardiac arrest. As such, the best– and only– effective on-field treatment for it is effective CPR and the use of an AED. Effective CPR requires the administrator to provide compressions at a depth of 2 inches and a rate of 100-120 bpm. These compressions are to be given in a 30:2 compression-to-breath ratio. When possible, it is preferable to use an AED, which has a significantly higher resuscitation rate than CPR. An AED should be used as soon as possible to provide the highest chance of survival. If the AED fails to resuscitate a patient, an additional 5 cycles of CPR should be performed before shocking the patient.

In commotio cordis survivors, healthcare providers may utilize a therapeutic hypothermia treatment to help patients with difficulty in responding to commands. With this treatment, the patient is cooled to 93.2ºF and their oxygen usage is lowered to reduce their metabolic rate and oxygen consumption in order to prevent swelling in the brain.

Risk Factors:

Commotio cordis is a spontaneous event caused by a series of actions that need to perfectly align in order to cause this injury. As such, there are no physical risk factors that directly cause this to occur. However, commotio cordis occurs more frequently in baseball, lacrosse, or hockey: all sports that involve dense objects with significant impacts in men younger than 20 years old.

Current Regulations:

Recent findings regarding commotio cordis have led to the remodeling of several pieces of sports equipment. They’ve also introduced new standards, namely the NOCSAE certification. Managed by the Safety Equipment Institute, NOCSAE standards promote safety by regulating production of safer sports equipment. For example, in a recent ruling, the National Federation of State High School Associations (NFHS) stated that, effective January 1st, 2020, all chest protectors used by high school athletes would be required to be NOCSAE-certified. These unique protectors featured a thicker central pad and protective plastic insert.

Conclusion:

In light of the Damar Hamlin incident, calls for increased CPR and AED training in young adults have erupted. In large part, Hamlin is alive today because of the swift actions of the medical team at the Bills vs. Bengals game that night. Because of recent research, commotio cordis is increasingly becoming better understood, allowing for improvements in equipment and treatment to help save lives.

Sources:

AHA Editorial Staff. “What Is Commotio Cordis?” Www.Heart.Org, American Heart Association, 19 Apr. 2023, www.heart.org/en/health-topics/commotio-cordis.

professional, Cleveland Clinic medical. “Commotio Cordis: Causes, Symptoms & Treatment.” Cleveland Clinic, my.clevelandclinic.org/health/diseases/24572-commotio-cordis. Accessed 18 Feb. 2024.

Palacio, Luis E, and Mark S Link. “Commotio Cordis.” Sports Health, U.S. National Library of Medicine, Mar. 2009, www.ncbi.nlm.nih.gov/pmc/articles/PMC3445066/#:~:text=Resuscitation%20within%203%20minutes%20resulted,%25%20to%2015%25%20since%202001.

Tainter, Christopher R. “Commotio Cordis.” StatPearls [Internet]., U.S. National Library of Medicine, 5 Feb. 2023, www.ncbi.nlm.nih.gov/books/NBK526014/.

Farrokhian, Ali Reza. “Commotio Cordis and Contusio Cordis: Possible Causes of Trauma-Related Cardiac Death.” U.S. National Library of Medicine, 15 Oct. 2016, www.ncbi.nlm.nih.gov/pmc/articles/PMC5253203/#:~:text=The%20most%20important%20variable%20in,will%20cause%20VF%20(4).