The goal of this pilot study is to evaluate the feasibility of an eHealth intervention for cardiac patients during their waiting period before their rehabilitation.

The main questions it aims to answer are:

• What is the feasibility of an eHealth intervention designed for cardiac patients with a low socio-economic position during the waiting period before their cardiac rehabilitation.
• What is the potential effect of this intervention on patient activation and feelings of certainty and guidance.

Participants will:

• Be randomised in either intervention or control group
• Fill in a questionnaire at the start of their waiting period (after release from the hospital)
• Use the eHealth intervention during their waiting period (usually 2 to 6 weeks)(intervention group only)
• Fill in a questionnaire at the start of their rehabilitation

Researchers will compare intervention and control group to see if the intervention has improved patient activation and feelings of certainty and guidance.

Health disparities between socioeconomic classes are growing. Certain neighbourhoods with a lower socio-economic position (SEP) display generally a higher prevalence of unhealthy lifestyles. A possible cause is lower levels of patient activation (being able to manage your health). Improving patient activation for some groups therefore seems important to facilitate their success within their cardiac rehabilitation (CR). In a preliminary study we found that patients indeed have a passive attitude towards their condition, especially during the so-called 'waiting period' (the period between discharge from the hospital and start of the rehabilitation). Activating patients in this period could be beneficial for the success of their upcoming rehabilitation as well as their long-term health. Therefore, we have developed a tailored eHealth intervention aimed at improving patient activation levels by supporting patients with a low SEP during their waiting period. The goal of this randomised pilot study is to assess the feasibility of this tailored eHealth intervention for cardiac patients with a low SEP and explore its effect on patients activation, certainty and guidance compared to usual care. The study population consists of patients (>18 years) with a low SEP who are eligible for participation in CR and have been referred to CR by their cardiologist.

Patients will be enrolled in the intervention group based on randomization. The intervention group will use an eHealth application during the waiting period before CR starts. The app asks patients to engage with preparatory messages daily. Messages are pre-made and consist of videos about the rehabilitation, written tips and spoken success stories. The control group will go through the usual waiting period before the start of CR.

Both intervention and control group will receive CR as usual, as recommended by guidelines. Before CR starts, participants in the intervention group are asked to use an eHealth application daily. The app shows daily messages provided by representatives of different disciplines within CR. Use of the app per day depends on the length of messages but can range between 5 and 10 minutes per day. The content of the app is developed in collaboration with healthcare workers at the rehabilitation center. Patients in the control group do not have this eHealth application in their waiting period.

Both groups will be asked to fill in a questionnaire at two moments during their rehabilitation:

T1: Face-to-face group meeting within one week after signing enrollment in CR (rehabilitation agreement) about demographics, certainty, guidance and activation consisting of 25 questions and taking approximately 8 minutes.

T2: At the start of the rehabilitation (usually after 2 to 6 weeks from T1) about:

Control: Certainty, guidance, and activation consisting of 22 questions taking approximately 7 minutes.

Intervention: Acceptability, certainty, guidance, and activation, consisting of 31 questions and taking approximately 10 minutes

Inclusion Criteria:

• The patient is eligible for participation in cardiac rehabilitation
• The patient has signed the standard rehabilitation agreement provided by the rehabilitation centre and has agreed to be contacted for research purposes
• The patient is aged 18 years or above
• The patient signs an informed consent form
• The patient is sufficient in the Dutch language
• The patient has access to a mobile phone with internet
• The patient is identified as someone with a low SEP, which will be determined by the socioeconomic status of the neighbourhood

Exclusion Criteria:

• Upon referral, the medical status of the patient is screened by a physician of the CR center. Patients with severe physical, psychological, or cognitive impairments will not be included in the study.