An implantable cardioverter defibrillator (ICD) is a small device that is implanted in the
chest and uses electrical shocks to control arrhythmias, which are abnormal heart rhythms.
Arrhythmias can be caused by many factors, including stress and anger. This study will
evaluate the use of a stress reduction treatment (SRT) program aimed at reducing the
occurrence of arrhythmias that require treatment with an ICD shock.
An ICD is a device designed to quickly detect a life-threatening, rapid heartbeat. Through a
process called defibrillation, the ICD tries to convert an abnormal heart rhythm back to
normal by delivering an electrical shock to the heart. The ICD continuously monitors
heartbeats to ensure that they are normal, and it only delivers a shock to the heart when it
senses a life-threatening arrhythmia. Because of the recent funding approval by Medicaid, it
is now estimated that more than 500,000 people will receive ICDs annually. Although ICDs are
life-saving medical devices, some people may experience anxiety, depression, and impaired
quality of life as a result of the repeated ICD shocks. Additionally, increased mental and
emotional stress and anger may increase the likelihood of experiencing more arrhythmias
requiring an ICD shock. SRT programs that encourage people to manage their emotions may
decrease the frequency of arrhythmias. Furthermore, SRT programs have been shown to be
successful at reducing other stress-related heart conditions. The purpose of this study is to
evaluate the effectiveness of an SRT program at reducing the incidence of ICD shock-treated
arrhythmias among people with newly implanted ICDs.
This study will enroll people who have recently received an ICD. Initially, participants will
complete questionnaires about mood and attitudes. Next, at a baseline study visit,
participants will complete a mental stress exercise in which they will perform math problems
and describe an experience that made them angry. During this exercise, participants will
undergo blood pressure measurements, blood collection, and an electrocardiogram (EKG) to
measure electrical activity of the heart. Participants will also wear a monitor for 24 hours
after the study visit to record heart activity. Participants will then be randomly assigned
to either take part in the SRT group and receive usual care or only receive usual care. For
10 weeks, participants in the SRT group will attend 8 group sessions that will focus on
learning and applying stress reduction techniques to everyday living. All participants will
attend a 3-month follow-up visit for repeat baseline testing. At Months 6, 12, and 24,
participants will complete questionnaires during routine doctor's visits or by mail.
- Receiving an ICD or currently have an ICD and have recieved appropriated ICD shock
therapy in the 6 months before study entry
- Ischemic cardiomyopathy or non-ischemic (dilated) cardiomyopathy
- Fluent in spoken and written English
- Able to participate in the SRT program
- Unable to comply with the study or participate in SRT treatment, if assigned
- Incapacitating illness (e.g., stage IV congestive heart failure) that would interfere
with study participation
- Life expectancy of less than 2 years (e.g., due to metastatic cancer)
- Uncommon etiologies of arrhythmia (e.g., long QT syndrome, hypertrophic
cardiomyopathy, Brugada syndrome)
- Cognitive impairment, based on Mini-Mental Status Exam (MMSE) and educational level.
If education level is less than 8th grade, then people with an MMSE score of less than
17 will not be enrolled; if education level is greater than 8th grade, then people
with an MMSE score of less than 24 will not be enrolled.