Sudden cardiac arrest on the field of play: turning tragedy into a survivable event

The sudden collapse and death of a young athlete on the field of play is a tragic event with a profound impact on the local community. Sudden cardiac arrest (SCA) is the leading cause of sudden death in athletes, accounting for 75% of all deaths during exercise and sport [1]. Recent epidemiological data have shown that SCA strikes competitive athletes more frequently than historical estimates. For example, annual risks have been shown to be 2.3:100,000 in Italian athletes [2] and 1–3:100,000 in professional soccer players [3]. The Fédération Internationale de Football Association (FIFA) has begun a registry to study all cases of soccer-related SCA to better understand the extent of the problem [4]. In the United States, male athletes, African/Afro-Caribbean athletes and basketball, American football and soccer athletes are at highest risk [1, 5‐12]. The cardiovascular diseases and conditions that precipitate SCA comprise a heterogeneous group of disorders that usually exhibit no symptoms or warning signs prior to the sentinel event of SCA [1, 12]. As a result, preparticipation cardiovascular screening is challenging and the optimal strategy to detect athletes with disorders at risk of sudden death remains controversial [13‐15]. Thus, medical personnel responsible for athlete safety must be prepared to recognise, respond to, and effectively treat SCA.

SCA is a life-threatening event and requires a prompt and coordinated medical response. Preparation and rehearsal of an emergency action plan (EAP) are essential to decrease the chance of a catastrophic outcome. Guidelines for the development and implementation of an EAP have been previously outlined [15‐19] and are broadly supported by the sports and medical communities. A comprehensive EAP includes training of likely first responders to a collapsed athlete, including on-site medical and club personnel, as well as access to an automated external defibrillator (AED), emergency medical services, and advanced care facilities (Tab. 1). A thorough understanding of emergency preparedness guidelines is imperative to allow for the efficient execution of the medical response to SCA.

Historical survival rates to hospital discharge following out-of-hospital cardiac arrest in the general population have been poor, as low as 7.6% [26]. The time from collapse to defibrillation following the onset of SCA is the single most important determinant of survival [27]. Modern public access AED programmes have yielded higher survival rates of 19.7 to 44% [20‐24]. A meta-analysis reported a median survival rate of 40% with public access to AEDs [20].

Access to early defibrillation also improves survival in young athletes with SCA. In a 2-year prospective observational study of 2,149 high school campuses, student-athletes with SCA survived 89 % of the time if prompt CPR and defibrillation were provided [28]. Survival was also higher if an on-site AED was used versus supplied by responding emergency medical services [28].

AEDs should be strategically located to allow a collapse-to-shock time of under 3 min. Epidemiological data can also be considered to prioritise specific locations. Studies demonstrate that the incidence of SCA in United States athletes is higher in certain subgroups, specifically male athletes, African/Afro-Caribbean athletes and American football, basketball, and soccer players [1, 5‐12]. In schools and community complexes, the gymnasium is the most likely site for SCA and offers a central location for AED placement that services a number of sporting activities and large public gatherings [13, 28]. The size of the venue and number of anticipated event spectators may also influence AED placement, as on-site medical personnel may be best positioned to assist a collapsed spectator prior to emergency medical services arrival. Guidelines are available regarding the number and location of AEDs in large sporting venues and arenas [29‐31].

For large mass-participation events such as marathons and triathlons, emergency care is ideally provided along the full length of the course. However, SCA during long-distance runs occurs more frequently in the late stages of the race [32, 33]. These data should be considered when making resource allocation decisions, such as the pre-race distribution of AEDs, placement of roaming or bicycle emergency medical service responders, and organisation of finish line ‘catchers’ and medical volunteers.

Exercise can increase the risk of SCA in athletes with underlying structural or electrical cardiac disorders [2]. Any athlete who collapses without obvious head trauma and is unresponsive on the field of play should be assumed to be in SCA until proven otherwise. Blunt trauma to the chest causing collapse, usually from a firm projectile, is consistent with commotio cordis and should also be treated as SCA.

In over 50% of cases, athletes with SCA demonstrate brief myoclonic or seizure-like activity following collapse [9, 34]. Thus, SCA should not be mistaken for an epileptic seizure, which may delay the initiation of CPR, retrieval of an AED, or even discourage these critical steps altogether. Athletes with SCA may also display abdominal movements or gasps that can be mistaken for normal breathing. In this scenario, rescuers may misinterpret these agonal respirations and delay the recognition and treatment of SCA. To avoid life-threatening delays in resuscitation, brief seizure-like activity and/or agonal respirations should be assumed due to SCA in a collapsed and unresponsive athlete, and initial management steps for SCA should be taken immediately, unless a non-cardiac cause of collapse is clearly determined. Furthermore, the myth of a need to prevent ‘tongue swallowing’ after collapse has been shown to delay bystander chest compressions [35] and should be discouraged as an unnecessary procedure during resuscitation.

Management of SCA on the field of play starts with making a prompt diagnosis. Once SCA is suspected or confirmed, the EAP should be initiated expeditiously. If multiple rescuers are available, one rescuer should begin CPR while another rescuer contacts emergency medical services and a third retrieves the closest AED if one is not already on the field of play. If there is only one rescuer, emergency medical services should be activated and then an AED obtained if readily available, with the rescuer returning to the victim to apply the AED and begin CPR.

CPR should commence at the site of athlete arrest, beginning with chest compressions in the case of a witnessed collapse. Moving the athlete to a different location may delay the resuscitation and could lead to worse outcomes [36]. Medical personnel should be prepared to quickly remove protective padding, clothing, or other equipment that may impede the initiation of CPR; this may require specialised tools or equipment. Chest compressions should be at least five to six centimetres or two inches in depth, allow complete chest recoil, and occur at a rate of 100–120 per minute [37, 38]. CPR should continue uninterrupted until an AED is applied and begins to analyse the athlete’s cardiac rhythm.

Rescuers should exercise considerable caution in excluding SCA in a collapsed and unresponsive athlete. Since the vast majority of these athletes are in ventricular fibrillation, an AED should be applied and turned on for rhythm analysis as soon as possible. AEDs are extremely accurate in recommending a shock when ventricular fibrillation or rapid ventricular tachycardia is present. If defibrillation is provided, chest compressions should resume immediately after shock delivery. If a shock is not advised, CPR should be continued until advanced life support providers take over or the victim starts to move. High-quality CPR should continue until return of spontaneous circulation is achieved or death is declared at a receiving facility [37, 38].

SCA in athletes is a life-threatening event that can precipitate confusion during sporting events. Development and rehearsal of a site-specific EAP is essential to ensure an efficient response and the best chance of survival. With prompt and accurate recognition of SCA, provision of high quality CPR, and access to early defibrillation via strategically placed AEDs, SCA in an exercising athlete is largely a survivable event.