A Stress Reduction Program to Reduce Abnormal Heart Rhythms Treated With Implantable Cardioverter Defibrillators:The RISTA Study

Interview by Jodie Elrod
Interview by Jodie Elrod
In this interview we speak with Matthew M. Burg, PhD, Associate Clinical Professor of Medicine at Yale University School of Medicine. Dr. Burg is the Principal Investigator of the Reducing Vulnerability to ICD Shock Treated Ventricular Arrhythmias (RISTA) Study, a randomized, single-blind trial currently underway. What prompted the RISTA study? What is the purpose of the RISTA study? In our previous research, we found that engaging in cognitively stressful tasks or describing a previous event that provoked anger, resulted in electrophysiological effects of a pro-arrhythmic nature among patients with implantable cardioverter defibrillators (ICDs). Furthermore, we found that the experience of moderate to extreme anger during routine daily activities increased the risk of an arrhythmia requiring shock for termination in this group. Thus, the purpose of the RISTA Trial is to determine whether teaching ICD patients how to manage/reduce routine stress: 1) reduces the likelihood of them having an arrhythmia requiring shock for termination; 2) limits the electrophysiological effects of stress; and 3) improves quality of life. How many patients and clinical sites are participating in the trial? We plan on enrolling 304 patients at 3 sites — Yale affiliated hospitals, Hartford Hospital, and Columbia University Medical Center. Tell us about the aspects of the stress reduction treatment (SRT) program. The stress reduction treatment is delivered in a group context, with eight 1½ hour sessions conducted over a 10-week period. At each session we cover a different aspect of stress reduction methods, including: 1) a focus on the automatic thoughts that arise during stress and give rise to strong emotions, and how to re-direct these automatic thoughts in a more useful direction so as to gain control over negative emotions; 2) how to use communication more effectively to reduce stress in social and work situations; 3) how to use standard and structured problem solving approaches to respond more effectively to the demands of each day; 4) how to distinguish important activities from compelling activities and how to use commitment-driven goals to gain greater control over the day; 5) how to use a range of physical relaxation strategies (e.g., progressive muscle relaxation, diaphragmatic breathing, visualization) throughout the day to keep stress from getting out of hand. Are similar SRT programs in place elsewhere? How have similar SRT programs been successful in other areas of cardiology? The approach we are using in RISTA is standard for stress reduction training and broadly follows the cognitive behavioral stress management strategies that are widely utilized in both practice and research. Similar protocols have been used in the group part of the intervention used for the ENRICHD (Enhancing Recovery in Coronary Heart Disease Patients) clinical trial with depressed post-ACS patients, and by Blumenthal et al in their clinical trial of treatment for patients with mental stress-provoked ischemia. How will participants be tested? The primary outcome for the study is incidence of ICD activity (shock, pacing) for ventricular arrhythmias. Secondary outcomes include the electrophysiological response during performance of stressful tasks in the laboratory, and quality of life (e.g., depression, anxiety, anger, coping) assessed on a psychosocial questionnaire at study entry and every several months over the two-year period of study participation. What other treatment or coping options for stress are currently available for ICD patients? How are these comparable? The approach we are taking to stress reduction is very comparable to what patients can find in working with psychologists or associated healthcare providers trained in cognitive behavioral approaches to psychosocial treatment. How do stress and anxiety factor in when triggering ICD shocks? Is there a population of patients who more often experience ICD shocks? Stress, anger, and perhaps anxiety all have the effect of increasing sympathetic nervous system activity and reducing parasympathetic activity. One result is an increase in the level of stress hormones that circulate in the body. These stress hormones alter the electrophysiological properties of cardiac control in a direction that makes a ventricular arrhythmia more likely to occur. It’s important to understand that individuals with an ICD already have a degree of compromise to the conduction system of their hearts, thereby making them more vulnerable to these effects. The occurrence of ICD shocks is hard to predict. That said, our research has shown that individuals prone to experience anger when under stress are more likely to have an arrhythmia that requires a shock for termination when they are under stress. Other research has shown that anxiety and depression — each a consequence of repeat ICD shocks — also increases the likelihood of an arrhythmia that requires a shock for termination, acting in a downward spiral. How is the RISTA study unique? Why was it important to study this aspect of living with an ICD? RISTA is the first randomized clinical trail of a stress reduction intervention that should have sufficient statistical power to determine whether this approach affects shock outcomes. Prior approaches were smaller and focused largely on quality of life outcomes. Since RISTA has been underway, a few other clinical trial shave emerged. What are the start and completion dates for the RISTA study? When will results most likely be available? Recruitment for RISTA has been underway for approximately 1½ years, and the study is projected to be complete in 4½ years. We should have the results at that time. Is there anything else you’d like to add? Stress is not only a significant risk factor for ICD patients, but for patients with heart disease and for those prone to experience anger when under stress. It is essential that further work be done to determine whether this relatively simple and non-invasive approach to care improves medical outcomes, reduces overall healthcare costs, and improves quality of life for these other groups.