Resuscitation 85 (2014) 1612–1618 Contents lists available at ScienceDirect Resuscitation j ourna l ho me pa g e: www.elsevier.com/locate/resuscitation Clinical Paper Myocardial infarction is a frequent cause of exercise-related resuscitated out-of-hospital cardiac arrest in a general non-athletic population Helle Søholm a,∗ , Jesper Kjaergaard a , Jakob Hartvig Thomsen a , John Bro-Jeppesen a , Freddy K. Lippert b , Lars Køber a , Michael Wanscher c , Christian Hassager a a Department of Cardiology 2142, The Heart Centre, Copenhagen University Hospital Rigshospitalet, Denmark b Emergency Medical Services, Copenhagen, The Capital Region of Denmark, Denmark c Department of Cardiothoracic Anesthesia 4142, The Heart Centre, Copenhagen University Hospital Rigshospitalet, Denmark a r t i c l e i n f o Article history: Received 15 April 2014 Received in revised form 25 May 2014 Accepted 22 June 2014 Keywords: Exercise Cardiopulmonary resuscitation Cardiac arrest Heart Myocardial infarction a b s t r a c t Background: Performing exercise is shown to prevent cardiovascular disease, but the risk of an out-of- hospital cardiac arrest (OHCA) is temporarily increased during strenuous activity. We examined the etiology and outcome after successfully resuscitated OHCA during exercise in a general non-athletic population. Methods: Consecutive patients with OHCA were admitted with return of spontaneous circulation (ROSC) or on-going resuscitation at hospital arrival (2002–2011). Patient charts were reviewed for post- resuscitation data. Exercise was defined as moderate/vigorous physical activity. Results: A total of 1393 OHCA-patients were included with 91(7%) arrests occurring during exercise. Exercise-related OHCA-patients were younger (60 ± 13 vs. 65 ± 15, p < 0.001) and predominantly male (96% vs. 69%, p < 0.001). The arrest was more frequently witnessed (94% vs. 86%, p = 0.02), bystander CPR was more often performed (88% vs. 54%, p < 0.001), time to ROSC was shorter (12 min (IQR: 5–19) vs. 15 (9–22), p = 0.007) and the primary rhythm was more frequently shock-able (91% vs. 49%, p < 0.001) compared to non-exercise patients. Cardiac etiology was the predominant cause of OHCA in both exercise and non-exercise patients (97% vs. 80%, p < 0.001) and acute coronary syndrome was more frequent among exercise patients (59% vs. 38%, p < 0.001). One-year mortality was 25% vs. 65% (p < 0.001), and exercise was even after adjustment associated with a significantly lower mortality (HR = 0.40 (95%CI: 0.23–0.72), p = 0.002). Conclusions: OHCA occurring during exercise was associated with a significantly lower mortality in suc- cessfully resuscitated patients even after adjusting for confounding factors. Acute coronary syndrome was more common among exercise-related cardiac arrest patients. © 2014 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Although the beneficial effects of regular exercise have been proven for both secondary and primary prevention of cardiovascu- lar disease, it is well known that the risk of an acute cardiac event is temporarily increased during strenuous physical activity – termed the paradox of exercise. 1–3 Sudden cardiac death is tragic and cardiac arrests occurring during exercise and sport activities fre- quently draw attention. The extensive attention of exercise-related ∗ Corresponding author at: Department of Cardiology 2142, Copenhagen Univer- sity Hospital Rigshospitalet, 9 Blegdamsvej, 2100 Copenhagen, Denmark. E-mail address: helle.soholm@gmail.com (H. Søholm). cardiac arrest and the following concern may refrain some from exercising. Survival after out-of-hospital cardiac arrest (OHCA) has increased in recent years, however OHCA remains associated with a poor prognosis. 4 Most current studies on OHCA during sport and exercise focus on sudden death in young professional athletes and the discussion of screening prior to participation in elite sports is ongoing in many countries. 5–8 Myocardial infarction is the most common cause of malig- nant arrhythmias leading to cardiac arrest and minimizing the delay from symptom onset to first medical contact in the pre- hospital setting is recognized as a major factor for outcome. 9,10 The establishment of emergency medical teams educated in basic life support (BLS) and equipped with an AED in sport stadiums and athletic settings have been suggested to improve fast response http://dx.doi.org/10.1016/j.resuscitation.2014.06.033 0300-9572/© 2014 Elsevier Ireland Ltd. All rights reserved.