A study, presented as a late-breaking trial at HeartRhythm 2012 (9–12 May, Boston, USA), shows that sports participation of patients with an implantable cardioverter defibrillator (ICD), in many athletes, is not associated with any serious adverse events.
Lead author and study presenter Rachel Lampert, Yale University School of Medicine, New Haven, USA, explained that the “postulated risks” of sports participation in patients with an ICD included the inability of the ICD to defibrillate because of the effects of the vigorous exercise, death, and syncope-related injury. She added that as a result of these potential risks, international guidelines do not recommend that people with ICDs participate in “all moderate and high intensity” sports. However, she said: “There are very few data actually investigating whether this is true [ie, that vigorous sport is not safe] and whether these risks will happen.” Therefore, the aim of Lampert et al‘s study was to identify and follow athletes with ICDs participating in competitive and dangerous sports to quantify the risk associated with sports participation.
The primary endpoints, Lampert reported, were “failure to convert an arrhythmia resulting in the need for external resuscitation or death during or after sports participation” and “Injury due to arrhythmia or shock during sports.” Secondary endpoints were shocks and arrhythmias resulting in multiple shocks for termination and damage to the lead or generator. Through medical centres or web-based patient advocacy groups, 372 patients with ICDs who participated in competitive or dangerous sports were identified. The mean age of patients was 33 (range 10-60 years) and follow-up (through telephone interview) was every six months.
After a mean follow-up of 31 months, the primary endpoint did not occur in any of the patients surveyed. However, 18% of participants did receive a shock and there were eight ventricular arrhythmia episodes that required multiple shocks. Of the 37 participants who received a shock during sports, four stopped playing sports completely and seven stopped one or more sports. Lampert said: “Even if people got shocked during sports, most of them went right back. Shocks are considered an adverse event–they are painful. As physicians, we do what we can to try to avoid shocks. On the other hand for these people, even though they did not like receiving a shock, the quality of life that sports were giving them was more important than whatever effect these occasional shocks had on their quality of life.”
The study, according to Lampert, is the first to collect data on a large number of people with ICDs who are actively participating in vigorous sports. She said there were two implications of the study. “First, a blanket restriction on sports for all patients with ICDs does not seem to be necessary. It is also important to note that these results do not suggest that all patients with ICDs should be participating in sports. Therefore, the second implication is that the decision to participate in sports in patients with an ICD needs to be an individualised decision.” She added that the physician needed to examine the patient and review the potential for shocks if they were to participate in sports.
Lampert concluded: “Prior to this study, we did not know the risks of playing sports in patients with ICDs. Now, we could say that the risk of playing sports is probably lower than had been hypothesised.”