In medical training, we are educated about a wide variety of medical conditions. Our training ranges from understanding and recognizing the most common medical problems to the most unusual or rare. When we hear the proverbial hoofbeats, a constellation of illness signs and symptoms, we are instructed to think of horses, not zebras. “Horses” equate with the common diagnoses that we should think of, and “zebras” denote rare diseases and disorders. However, the idea of the “zebra” diagnosis is relative to the audience involved.
If you ask a pediatric intensivist who works in a cardiothoracic ICU, the anatomic defects of the heart that affect 1% of infants, with only one-quarter of those defects requiring some intervention, is an everyday diagnosis. The infant with one main heart-pumping chamber instead of two (hypoplastic left heart syndrome), a heart rotated into the right side of the chest instead of the left (dextrocardia), and the aorta and pulmonary artery originating on the wrong sides of the heart (transposition of the great arteries) are “horses” and not “zebras” for this type of physician.
Having knowledgeable experts who easily recognize and manage rare medical conditions is critical to the advancement of medicine and proficiency in the medical management of these rare medical conditions. However, it is important for non-experts to have some understanding of the occasional rare medical conditions as well. A good example of this is the recent, televised, on-field cardiac arrest of the 24-year-old Buffalo Bills safety, Damar Hamlin.
Commotio Cordis
While there are approximately 356,000 out-of-hospital cardiac arrests in the US per year (nearly 90% of which are fatal), the annual incidence is relatively low considering the 332 million population of the US. Most of the public will never see or need to manage a person with a cardiac arrest. This incidence is even lower when you consider that about 2,000 young, seemingly healthy people under the age of 25 in the United States die each year of sudden cardiac arrest. While we don’t know for sure, the cardiac arrest of Damar Hamlin was thought to be due to a rarer condition, commotio cordis, in which a blunt force trauma to the chest induces a cardiac arrest due to ventricular fibrillation. There are approximately 10-20 cases of commotio cordis per year.
Even though Damar’s story makes for great news headlines and may be great for viral viewership, I would argue that his story is more important than just “clickbait.” Some would criticize the press or social media for taking advantage of Damar’s critical incident to get views or “likes.” But his story, along with other high-profile reports—like Michael J. Fox with Parkinson’s disease, Selena Gomez with systemic lupus erythematosus, or Jimmy Kimmel with narcolepsy—is important to bring awareness of rare diseases to the public so they aren’t such a mystery.
Think About the Zebras
If the public is more aware of these kinds of conditions, it helps the experts who care for these conditions. Through a greater, broader understanding of rare medical conditions, there is a higher likelihood of non-experts starting care like CPR or bringing signs and symptoms to the attention of those experts who can rapidly recognize and assess patients to initiate the proper treatment and care.
Damar’s sudden cardiac arrest and recovery emphasize the importance of the recognition of sudden cardiac arrest and prompt CPR with the use of an AED. The rapid recognition of his symptoms, the institution of CPR, and the use of an AED saved his life. Because of his ailment and the widespread coverage of it, the public has learned more about sudden cardiac arrest and its management. The likely result of their education and exposure to the coverage of Damar’s story will be more lives saved. Damar’s incident underscores the importance of thinking about the relative “zebras” when one hears the proverbial hoofbeats, because a delay in recognition and management can prove fatal.
