A Case of Sudden Cardiac Death in a High School Athlete
In a case that was widely reported in the local and national media last September,1,2 a 17-year-old Texas athlete died after collapsing due to heart complications during a football game. The high school junior, who played defensive tackle on the varsity team, was participating in a game on a Friday night when he came off the field and fell to the ground.
After emergency personnel offered medical attention on the sidelines, the young man was taken to a San Antonio hospital, where he died early the next morning. According to news reports, an autopsy later found that the young athlete had died from cardiovascular complications—more specifically, an “abnormal coronary artery.”
Which of the following statements is most accurate in relation to this clinical vignette?
- After appropriate evaluation of such cases of sudden cardiac death (SCD), including autopsy findings and genetic testing, coronary artery disease will be the most likely definitive diagnosis in the population group aged 1 to 35 years.
- The finding of J waves or QRS complex slurring on previous preseason electrocardiograms will likely explain the event.
- Limiting physical activity represents an excellent way to reduce the incidence of SCD among children and young adults who have certain structural cardiac conditions.
- The etiology of SCD across patients of all ages between 1 and 35 years is essentially the same: coronary artery disease.
Answer on the next page
Answer: A, coronary artery disease will be the most likely diagnosis in the population group aged 1 to 35 years.
SCD in young people, defined for this article as those aged 1 to 35 years, is assuredly a catastrophic event by its very definition. Recent years have seen an initiative of having resuscitation equipment readily available in an ever-wider domain of public activities and sites in the hopes of lessening the incidence of SCD in patients of all ages. But for now, the stark absoluteness of SCD limits any discussion to continuing to study the problem clinically as best as possible and, hopefully, elucidating its epidemiology and etiology such that preventive measures can accrue and improve.
To review the scope of the problem, most studies place the incidence of SCD in young people at between 1.3 and 2.9 cases per 100,000 person years.3 In one of the larger studies comprising 490 cases,3 certain epidemiologic patterns emerged about SCD: The highest incidence is in the 31- to 35-year-old bracket, while the lowest incidence is in the 6- to 10-year-old bracket; the causation pattern of SCD differs among different age subsets; and—very surprisingly—by far, SCD most frequently occurs while a person is sleeping (38%) or at rest (27%) in contrast to during exercise (11%) or postexercise (4%). These observations contradict older paradigms that include exercise avoidance as a key part of prevention in young people known to have certain structural cardiac conditions, making Answer C an incorrect statement.
Study of the etiology of SCD continues to reveal “unexplained” as the most common cause. Genetic tests for a variety of known lethal genes associated with certain epilepsies, long QT interval arrhythmias, cardiomyopathies, and more rare conditions are now becoming increasingly available and should be a part of all postmortem evaluations of SCD cases. These studies should be complemented by genetic evaluations of siblings and parents, as well. Such studies appear to be able to make the diagnosis in up to 40% of SCD cases,3,4 and this number surely will increase as our knowledge and technical skills accrue.
Structural causes, the other major cause of SCD, include coronary artery disease, dilated cardiomyopathy, myocarditis, hypertrophic cardiomyopathy, and right ventricular abnormalities.3,4 In a study of veterans, including many hundreds of cases in persons between 20 and 35 years, the electrocardiography findings of early repolarization J-point elevation and QRS complex slurring, once thought to be an ominous risk factor for cardiovascular death, was not found to be an increased risk factor for the diagnosis for SCD,5 and thus Answer B is an incorrect statement.
Causation was not evenly distributed across age groups, with one very dominant etiology being present in the older group (aged 31-35 years), specifically coronary artery disease.3 This likely is not surprising in view of modern eating and exercise habits. Thus Answer D is also an incorrect statement.
Thus at this time, the best available data indicate that in cases of SCD in young people, a detailed autopsy and genetic testing should be performed—autopsy to reveal any causative structural abnormalities, and genetic testing of tissue and that of the patient’s relatives to reveal any genetic causes. Even after this degree of investigation, approximately one-third of cases still will be “unexplained.” However, in the two-thirds with identifiable causation, families can be evaluated and preventive interventions (eg, implantable defibrillators3,6) and genetic counseling can be initiated, with the hope of further reducing the incidence of these devastating events.
Ronald N. Rubin, MD, is a professor of medicine at the Lewis Katz School of Medicine at Temple University and is chief of clinical hematology in the Department of Medicine at Temple University Hospital in Philadelphia, Pennsylvania.
References:
- Keith D. Shadow Creek High School football player collapses during game, dies. Fox 26 Houston. http://www.fox26houston.com/news/204800780-story. Published September 12, 2016. Accessed January 9, 2017.
- Whelan T Jr. Texas high school football player dies after collapsing during game. USA Today High School Sports. http://usatodayhss.com/2016/texas-high-school-football-player-dies-shadow-creek-chase-lightfoot. Published September 12, 2016. Accessed January 9, 2017.
- Bagnall RD, Weintraub RG, Ingles J, et al. A prospective study of sudden cardiac death among children and young adults. N Engl J Med. 2016;374(25):2441-2452.
- Adabag AS, Peterson G, Apple FS, Titus J, King R, Luepker RV. Etiology of sudden death in the community: results of anatomical, metabolic, and genetic evaluation. Am Heart J. 2010;159(1):33-39.
- Pargaonker VS, Perez MV, Jindal A, Mathur MS, Myers J, Froelicher VF. Long-term prognosis of early repolarization with J-wave and QRS slur patterns on resting electrocardiogram: a cohort study. Ann Intern Med. 2015;163(10):747-755.
- Maron BJ, Spirito P, Shen W-K, et al. Implantable cardioverter-defibrillators and prevention of sudden cardiac death in hypertrophic cardiomyopathy. JAMA. 2007;298(4):405-412.