Interpreting Damar Hamlin’s Sudden Collapse – JohnLeake 1/3/23

Source: petermcculloughmd.substack.com

Dr. McCullough is in the midst of a long deposition, so he is unable to respond to the flurry of queries he received this morning about the sudden collapse of Damar Hamlin on the playing field last night. He just sent me an E-mail with the following assessment that he developed last night:

I watched the play live both as a fan and a cardiologist and I saw blunt neck and chest trauma, a brief recovery after the tackle and then a classic cardiac arrest. I have communicated to one of the most experienced trainers in the world and we agree that it was a cardiac arrest in the setting of a big surge of adrenalin. If Damar Hamlin indeed took one of the COVID-19 vaccines, then subclinical vaccine-induced myocarditis must be considered in the differential diagnosis. We have been told he was successfully defibrillated on the field and has been intubated and is not spontaneously breathing which is consistent with anoxic encephalopathy. The nation prays for his complete recovery.

That Damar Hamlin collapsed shortly after receiving a blow to his chest naturally raises the suspicion of commotio cordis—a blunt, nonpenetrating trauma to the chest resulting in irregular heart rhythm and often leading to sudden death.

Reviewing mainstream media reporting today, I see several doctors opining that commotio cordis was the likely cause of Hamlin’s collapse. A physician named Chris Haddock—whose Tweet was quoted in a Men’s Health report—felt compelled to add:

Those trying to tie this to vaccine status to project their unscientific beliefs are terrible, horrible people.

Three studies of commotio cordis—one published in 2002, another one published in 2009 and another one published in 2022 are worth reading in full. These studies indicate it is a complex phenomenon. To quote the first study:

Occurrence of commotio cordis is related to time of impact during the cardiac cycle, direct impact over the heart, the hardness and speed of the projectile, and the ineffectiveness of chest barriers.

The condition seems to occur most frequently in male athletes in their teens.

Young males, ages 4 to 18 years old, are at greatest risk. Vulnerability in this age group has been attributed to increased chest wall pliability, but it is unclear why there is a male predilection.

Somewhat counterintuitive is the finding that the event is frequently triggered by a projectile (most often a baseball) traveling at a relatively low velocity (around 40 MPH). When I first read this, I wondered if it was attributable to the fact that young males, ages 4 to 18 years old, can’t pitch much faster than 40 MPH. However, I then came to the part of the study documenting projectile velocity experiments on swine.

Link et al reported that projectiles traveling 40 mph were most likely to cause VF [Ventricular Fibrillation] in swine. Incidents of VF actually decrease when the velocity of the impact is between 50 and 60 mph.

To interpret Damar Hamlin’s sudden collapse from an epidemiological standpoint, it would be useful to examine other documented cases of commotio cordis that have occurred in NFL games.

A 2002 study published in JAMA analyzed 107 cases of commotio cordis reported the following:

Of 107 commotio cordis events that were regarded as part of competitive or other sporting activities, 87 (81%) involved a blunt precordial blow from a projectile (which served as a standard implement of the game), or another object propelled against a stationary chest wall, resulting in relatively localized contact, during organized or recreational play. Projectiles were most commonly baseballs (n = 53), including 50 of apparent regulation design, 1 hard rubber ball, and 2 others marketed commercially as reduced-injury, softer-than-normal (so-called safety or training) balls, made largely of rubber of various textures contained in a synthetic covering.

Other projectiles included 14 softballs, as well as 10 hockey pucks and 5 lacrosse balls, both of which are made of hard rubber. With the exception of 1 air-filled soccer ball, each projectile that resulted in commotio cordis had a hard solid core. Six of these 87 cases were innocent bystanders inadvertently struck in the chest by a thrown or batted ball, including spectators or players observing the game from the dug-out or bull pen.

A Google search of the words “football player commotio cordis” between the years 1970 and 2022 yielded ONE 2011 report of a junior varsity football player in Massachusetts who suffered from commotio cordis.

So far, I have been unable to find any documented cases that have occurred in the NFL. (Perhaps our readers can find some cases and share them with us).

This suggests that the age of NFL players and the protective padding over their hearts result in a lower incidence of commotio cordis than the incidence documented in sports such as baseball, in which players’ chests are exposed to a projectile.

In the final analysis, only a thorough physical examination of Damar Hamlin’s heart can determine what caused his sudden collapse. As Dr. McCullough stated in his initial assessment last night:

If Damar Hamlin indeed took one of the COVID-19 vaccines, then subclinical vaccine-induced myocarditis must be considered in the differential diagnosis….

Read More…