Acceptance and Mindfulness Based Exposure Therapy for Survivors of Cardiac Arrest

Overview

The primary goal of this uncontrolled pilot trial is to examine feasibility, acceptability, safety, and preliminary efficacy of a new behavioral treatment for survivors of sudden cardiac arrest with clinically elevated symptoms of post-traumatic stress disorder (PTSD). Participants will be recruited among cardiac arrest survivors enrolled in the observational CANOE research study (CUIMC IRB# AAAR8497). Study participants will be interviewed about their symptoms and evaluated for baseline assessment before receiving eight weekly sessions of an acceptance and mindfulness-based exposure therapy (AMBET). Participants will be additionally evaluated at treatment mid-point (week 4), and at the end of treatment. The treatment and all assessments will be conducted remotely via Zoom. To assess whether patients' physical activity is improved over the course of treatment, participants will be provided with a wearable device (Fitbit wristband) to monitor their physical activity. The specific aims of this study are to: (1) develop an acceptable protocol for an AMBET intervention for survivors of sudden cardiac arrest with elevated PTSD symptoms (2) examine its safety and feasibility in a small sample of 14 patients (3) investigate acceptability and feasibility of the assessments and measurements including physical activity.

Clinically elevated levels of PTSD symptoms occur in approximately 1 in 3 cardiac arrest survivors with intact cognitive function and are associated with increased risk for future cardiac events and mortality. Survivors of acute cardiovascular events are typically encouraged to monitor for somatic cues of cardiovascular activity that might indicate recurrent events. However, threat-related attention bias is a common sequela of trauma. In cardiac patients, this hypervigilant attention to interoceptive cues of danger may serve to maintain threat perception, as arousal amplifies awareness of internal stimuli. Elevated PTSD symptoms have also been associated with low adherence to physical activity and medication regiments in patients with elevated PTSD symptoms after other types of cardiovascular events in part because they can serve as traumatic reminders. Although several well-studied, validated treatments for PTSD exist, there is no evidence-based treatment for PTSD in cardiac arrest survivors. Standard PTSD interventions targeting fear extinction and threat perception in the context of current safety pose a problem in a population that is living with an actual ongoing cardiac threat. Thus, the investigators will be developing a de novo protocol for an Acceptance and Mindfulness-Based Exposure Therapy (AMBET) intervention that targets increased discriminatory perception through mindful interoceptive attention and adaptive threat responding. Initial evidence has been published to suggest the safety and potential efficacy of imaginal exposure in cardiac patients to reduce PTSD symptoms. Among PTSD treatments, exposure therapy is the most widely recommended. However, the efficacy is moderate, and high dropout rates are well documented. An innovative line of PTSD therapies can be found among mindfulness- and acceptance-based treatments. Although large scale RCTs are still limited, there are promising findings of treatment effects on reduced PTSD symptoms. Reported dropout rates have been low across treatments, indicating a high degree of treatment acceptability. The addition of mindfulness components to exposure therapy has been proposed to enhance the effects of exposure as well as the willingness to engage in them. Of particular interest for cardiac patients are findings that mindfulness-based approaches have normalized cortisol levels and reduced inflammatory biomarkers in PTSD patients, as these are physiological processes that have been implicated in the links between PTSD and cardiovascular risk. Several mechanisms have been posited to underlie the efficacy of mindfulness-based approaches including increased metacognitive awareness of interoceptive sensations and mind-body connections. Furthermore, and contrary to the associations found between hypervigilant interoceptive awareness and psychopathology, mindful attention to interoceptive cues has been linked with adaptive, resilience-enhancing behaviors. The goals of the AMBET treatment will be to reduce PSTD symptoms and hypervigilance to internal stimuli (i.e., interoceptive bias), and increase cardiovascular health behaviors (medication adherence, physical activity) following cardiac arrest. Following psychoeducation about PTSD and cardiovascular disease related health behaviors, participants will be engaged in in-vivo and imaginal exposure exercises to reduce avoidance responses. Participants will be introduced to acceptance and mindfulness-based strategies that will be practiced in session and as homework assignments. Eight 90 minute sessions will be delivered to patients individually on a weekly basis through HIPAA-compliant zoom-hosted video visits. Patient symptoms will be assessed by an independent evaluator before, at mid-point, and post-treatment. A within-subjects repeated measures design will be used to assess the feasibility of conducting all aspects of the study remotely, including recruitment, assessment, and treatment delivery.