Exercise-related resuscitated out-of-hospital cardiac arrest due to presumed myocardial ischemia: Result from coronary angiography and intravascular ultrasound

Abstract

Aim: Possible causes of exercise-related out-of-hospital cardiac arrest (OHCA) in people with coronary artery disease (CAD) include atherosclerotic plaque rupture (PR) and intra-coronary thrombosis, exercise-induced myocardial ischaemia and other triggers. We investigated whether there are differences in the incidence of PR and/or intra-coronary thrombus and in clinical outcome between 'exercise-related' and 'non-exercise-related' OHCA.

Methods: 219 consecutive resuscitated patients with CAD diagnosed by emergency coronary angiography (CAG) were enrolled. They were divided into the exercise group (≥6 METs; n = 35) and non-exercise group (<6 METs; n = 184), according to estimated METs immediately before OHCA using 2011 Compendium of Physical Activities. We investigated whether culprit lesions had PR and/or thrombus using CAG and intravascular ultrasound. The clinical outcome was 30-day survival with minimal neurologic impairment.

Results: Acute PR and/or thrombus occurred in fewer of the exercise group than the non-exercise group (11% vs. 90%; P < 0.001). The exercise group had a higher incidence of favorable neurological outcome (94% vs. 47%; P < 0.001) than the non-exercise group. Multivariable Cox proportional hazards models revealed that exercise immediately before OHCA was one of the predictors of a good neurological outcome (HR, 0.19; P = 0.025).

Conclusion: The incidence of PR and/or thrombosis was lower in the group taking higher levels of exercise, than in the group taking less or no exercise. "Exercise-related" OHCA with CAD has better clinical outcomes than "non-exercise-related" with a greater proportion of witnessed arrests and early return of spontaneous circulation.

Keywords: Exercise; Plaque rupture; Sports cardiology; Sudden cardiac arrest.