Background: Congenital heart defects (CHD) are associated with disease-related stressors and negative emotions, resulting in an increased prevalence of psychopathology. However, evidence-based psychological interventions for individuals with CHD are scarce. Emotion regulation abilities might be central for determining whether individuals with CHD develop symptoms of psychopathology or successfully adjust to the illness-related regulatory demands. Therefore, psychological online interventions targeting emotion regulation might provide low-threshold access to treatment and enhance well-being in individuals with CHD.

Methods: We developed the first online psychological intervention for individuals with CHD in Germany and investigated predictors of intervention adherence in a three-armed randomized clinical trial. A total of 246 patients with CHD recruited by the German National Register for Congenital Heart Defects (18-68 years, 69.5% female) were randomly assigned to a general online emotion regulation intervention (IG1), a CHD-specific online emotion regulation intervention (IG2), or a waitlist control group (CG). The four-week interventions were based on cognitive behavioral therapy and included daily emotion regulation exercises and psychoeducation via video and audio files. Intervention adherence was defined as the number of completed days within the program (range: 0-28 days). Baseline depressive symptoms (Patient Health Questionnaire-9; Kroenke et al., 2001), anxiety (Generalized Anxiety Disorder-7; Spitzer et al., 2006), emotion regulation difficulties (Difficulties in Emotion Regulation Scale; Gratz & Roemer, 2004), and treatment motivation were captured as possible predictors of adherence.

Results: Preliminary results revealed that 45% of all participants completed at least half of all intervention days (> 13 days). Participants reported a high average treatment motivation of M = 6.37 (SD = 10.63), with 8 reporting the maximum possible score. Interestingly, adherence to the intervention was comparably high among both treatment groups, with no differences between the general online emotion regulation intervention (IG1) and the CHD-specific online emotion regulation intervention (IG2) (Cohen’s d = .12, p = .17). Moreover, regression analysis identified treatment motivation as a predictor of intervention adherence (β = .19, CI_95%[0.428, 2.554], b = 1.57, CI_95%[0.411, 2.607], p < .01). In contrast, symptoms of depression and anxiety, emotion regulation difficulties, and group affiliation (IG1 vs. IG2) did not significantly predict intervention adherence.