The goal of this clinical trial is to find out whether a simple augmented reality tool provided at hospital discharge can improve patients' understanding of their care, adherence to treatment, and health outcomes, compared with the usual discharge information.

This study includes adult patients who are admitted to a cardiology department because of:

• Ischaemic heart disease
• Atrial fibrillation
• Heart failure
• Or who need a pacemaker implantation

The main questions this study aims to answer are:

• Does providing augmented reality information at discharge improve patients' perceived quality of care?
• Does it improve patients' adherence to their prescribed treatment?
• Does it reduce major cardiovascular events such as hospital readmission, heart attack, stroke, or cardiovascular death?

Researchers will compare two groups of participants:

• A control group, who will receive the usual medical discharge report.
• An intervention group, who will receive the usual medical discharge report plus an information card with a drawing and a QR code that gives access to an augmented reality application.

Participants will:

• Receive their discharge information according to the group they are assigned to.
• Use the augmented reality application if they are in the intervention group.
• Be followed over time to assess treatment adherence, patient experience, and cardiovascular events.

This is a low-intervention, randomized, single-centre clinical trial conducted in Getafe, Madrid, Spain. Participation in this study does not involve taking any additional medication.

Inclusion Criteria:

• Participants must have access to a mobile device (such as a smartphone or tablet).
• Participants must have been admitted to the Cardiology Department of Getafe University Hospital for ischemic heart disease, heart failure, atrial fibrillation, or pacemaker implantation.

Exclusion Criteria:

• No access to a mobile device.
• Untreated visual or hearing impairments that prevent viewing or understanding the videos.
• Inability to understand Spanish

Individual Participant Data will not be shared because the dataset contains sensitive patient health information, including medical history and follow-up outcomes. Sharing these data could risk patient confidentiality. All data will be handled according to current data protection regulations and only anonymized, aggregated results will be made publicly available.