Sudden cardiac death secondary to acute aortic syndromes in young athletes in the United States

Sudden cardiac arrest and death (SCA/D) is the leading medical cause of death among young competitive athletes.¹ Prior studies have consistently demonstrated aortic disease to be an important albeit uncommon aetiology of SCA/D in this population.^1,2 However, data regarding the specific aortic pathologies and circumstances surrounding these cases remain limited. The primary aim of this study was to describe patient demographics, circumstances, and underlying cardiovascular pathology among young U.S. athletes who sustained SCA/D secondary to an acute aortic syndrome (AAS).

This study included young competitive athletes who sustained SCA/D due to AAS from 1 July 2002 to 30 June 2023 using the University of Washington Collegiate Athlete Death Database (UW-CADD)¹ and the National Center for Catastrophic Sports Injury Research (NCCSIR) Database.² UW-CADD included only SCD cases in U.S. collegiate athletes for the entire study period, whereas NCCSIR included both deaths and survivors from SCA/D from 1 July 2014 through 30 June 2023 (ages 11–29). Complete methods for case identification, study definitions, and adjudication processes have been previously published.^1,2 This study was approved by the University of Washington Division of Human Subjects and the Institutional Review Board at the University of North Carolina at Chapel Hill. Per ethics approval, our data are not available.

There were 454 cases of SCA/D with an adjudicated cause (326 deaths, 128 survivors) during the study period. An AAS was the cause in 14/454 (3%) cases, all resulting in SCD (Table 1). SCD from AAS was exertional in 7/14 (50%) athletes and non-exertional in 5/14 (36%), with exertional status unknown in the remaining 2/14 (14%). At least one SCD event was secondary to chest wall trauma while playing hockey in an athlete with bicuspid aortic valve (BAV) and aortic coarctation.

Table 1.

Clinical characteristics and post-mortem descriptions for athletes with sudden cardiac death secondary to acute aortic syndromes

Level of competition	Height (in)	Sport	Exertional status	COD adjudication	Aortic valve morphology	Aortic pathology	Molecular genetic results
Female athletes
High School	66	Basketball	Exertional	Autopsy	Tricuspid	Aortic dissection with rupture at aortic root. Normal thoracic aortic dimension.	ACTA2
College	66	Swimming	Exertional	Autopsy	Tricuspid	Aortic dissection with rupture at proximal ascending aorta.	None
College	77	Basketball	Sleep	Autopsy	N/A	Aortic dissection with rupture at aortic root. Aortic aneurysm measuring 6 cm. Multiple chronic appearing dissections.	FBN1
Male athletes
Middle School	69	Swimming	Sleep	Autopsy	Tricuspid	Aortic dissection with rupture at aortic coarctation (distal aortic arch) and proximal extension.	TGFBR1
High School	N/A	Ice Hockey	Exertional	Interview with Family	Bicuspid	Aortic aneurysm with traumatic rupture and aortic coarctation (no further details).	None
High School	N/A	Basketball	Unknown	Media Report	N/A	N/A	None
High School	72	Wrestling	Sleep	Autopsy	Bicuspid	Ascending aortic dissection with rupture at aortic root.	None
High School	80	Volleyball	Non-Exertional	Interview with Family	N/A	N/A	None
High School	N/A	Basketball	Unknown	Media Report	N/A	N/A	None
College	71	Football	Exertional	Autopsy	Tricuspid	Aortic dissection with rupture at aortic root.	None
College	80	Basketball	Exertional	Autopsy	Tricuspid	Aortic dissection with rupture at aortic root.	FBN1
College	73	Football	Exertional	Autopsy	Tricuspid	Aortic dissection at aortic root.	None
College	N/A	Track	Non-Exertional	Autopsy	N/A	Aortic dissection with rupture at aortic root.	None
College	74	Football	Exertional	Autopsy	Tricuspid	Aortic dissection with rupture at aortic root. Aortic aneurysm measuring 9 cm.	None

Definition of Abbreviations: COD, cause of death.

Ten AAS cases had available autopsy data, all of which demonstrated an aortic dissection involving the aortic root with associated haemopericardium. Only 4 AAS cases had genetic testing results available. Of these, 3/4 (75%) were found to have pathologic mutations associated with aortopathy (2 FBN1, 1 TGFBR1); the remaining athlete had a mutation in a gene associated with aortic disease (ACTA2), but this was classified as a variant of unknown significance. Aortic valve morphology was reported in 9/14 (64%) cases, with BAV identified in 2/9 (22%). Post-dissection aortic dimensions were described in only 3/10 (30%) autopsies and ranged from ‘normal’ to severely dilated (6 and 9 cm).

This study has several key findings. First, AAS are an infrequent cause of SCA/D among young competitive athletes and are often associated with the presence of heritable aortopathy syndromes when genetic testing is performed.³ Second, young competitive athletes with underlying aortopathy appear to be at-risk for AAS during both exertion and non-athletic daily living, although here it is important to note that even serious athletes spend only a minority of their time engaged in active exercise/training. Third, chest wall impact, a proposed trigger for AAS among athletes with underlying aortopathy, was associated with only one SCD in this series. Fourth, there were no survivors of SCA attributable to AAS, underscoring the limited effectiveness of current emergency action plans (EAPs) in this context. Finally, the use of post-mortem genetic testing was relatively uncommon, but the high diagnostic yield and associated potential utility for familial cascade screening highlight the importance of including genetic testing when an AAS is suspected or confirmed.

Contemporary U.S.⁴ and European guidelines⁵ both provide specific recommendations for athletes with varying types of aortopathy. Data defining cardiovascular outcomes among athletes with aortopathy, however, remain extremely limited, so these recommendations are almost universally based on expert consensus, and clinicians should utilize all available data in decision-making.^6–9 Future prospective, longitudinal studies are needed to better characterize the natural history of aortopathies in athletes. While we could not define the true incidence of SCA/D due to AAS (a primary limitation of this study), it is notable that AAS represent only 3% of all SCA/D cases, less than most other aetiologies of SCA/D.^1,2 Therefore, it is possible that risks among athletes with aortopathy may be less than expected, and this low overall percentage of athletes with SCA/D due to AAS may provide important context in the shared-decision-making process regarding return to athletic participation for athletes with aortic disease. At the same time, however, the true prevalence of aortopathy among athlete populations remains unknown. We accordingly advise cautious interpretation of this finding due to the inability to define the at-risk population, which precludes determination of AAS incidence.

Inherited aortopathies in isolation do not manifest changes on the 12-lead electrocardiogram (ECG) and accordingly are unlikely to be detected during pre-participation cardiovascular screening (PPCS), which is most often performed with a history and physical exam and ECG. While the addition of echocardiography could increase diagnostic yield for aortic disease, this practice is currently not universally recommended by major cardiovascular societies given limited prospective data.^4,5 This challenge highlights the importance of a thorough family history in PPCS, which can trigger imaging among athletes with a family history of aortopathy or BAV.

In contrast to many other aetiologies of SCA, all identified cases of AAS were fatal, underscoring the limitations of detection and emergency response/EAPs in this specific condition. Future studies should assess the efficacy of personalized EAPs for athletes playing with aortopathy (e.g. identifying nearby hospitals with aortic surgical expertise), as personalized EAPs have been recently highlighted as an essential component of the comprehensive management of all athletes with genetic heart disease.¹⁰ Similarly, our data also highlight the relative underutilisation of post-mortem genetic testing, which should be encouraged to improve diagnostic accuracy and inform cascade screening. While sample size is small, 3/4 athletes in this series who underwent testing had pathogenic mutations, suggesting that genetic evaluation in this context may have a high yield and provide more comprehensive risk evaluation.

In addition to limitations noted above, we also note that AAS as a cause of SCA/D may have been missed in cases without complete records for adjudication. Despite these limitations, these findings represent unique contemporary data defining the breadth of pathology and clinical circumstances associated with AAS in young competitive athletes.

Data availability

Per ethics approval, the data underlying this article cannot be shared publicly due to inability to fully de-indentify.