This multicenter prospective observational feasibility study evaluates the implementation of the RAPHAEL model, a remote monitoring palliative care approach for patients with heart failure. The study aims to assess the feasibility, acceptability, usability, and implementation outcomes of integrating structured remote symptom monitoring and palliative care needs assessment into routine outpatient heart failure care.

Adult patients with heart failure and worsening symptoms and/or potential palliative care needs will complete a structured digital questionnaire during a 4-week follow-up period. Healthcare professionals will review reported needs and conduct follow-up contact according to usual clinical practice. No experimental drugs or devices are administered, and clinical management remains at the discretion of the treating team.

Primary outcomes focus on feasibility and implementation metrics, including participation rates, acceptability, usability, perceived burden, resource requirements, fidelity to the intervention model, training adoption, applicability, adaptation, and demand.

The RAPHAEL study (Work Package 4) is a multicenter, prospective observational feasibility study conducted across participating European clinical sites. The objective is to evaluate the implementation of a structured remote monitoring palliative care model integrated into routine outpatient heart failure care.

Patients with a confirmed diagnosis of heart failure who present with worsening symptoms and/or indicators of palliative care needs will be invited to participate. Participants will complete a structured digital questionnaire designed to identify symptom burden, psychosocial concerns, and potential unmet palliative care needs. The questionnaire is administered once during a 4-week observation period.

Healthcare professionals trained in the RAPHAEL model will review questionnaire responses and may initiate follow-up contact or clinical actions according to standard clinical judgment and existing care pathways. The study does not mandate changes to pharmacological treatment, and all medical decisions remain under routine clinical practice.

The primary objective is to assess feasibility and implementation outcomes, including recruitment capability, participation rates, acceptability, usability, perceived burden for patients and professionals, fidelity to the intervention components, required resources, adaptation processes, and demand. Secondary objectives include descriptive assessment of symptom burden and identified palliative care needs.

The study is classified as an observational prospective study according to ethics committee approval. No randomization, experimental interventions, or investigational medicinal products are involved.

Inclusion Criteria:

Patients

1. Adult patients (≥18 years) with the main diagnosis of HF according to current guidelines (20), living at home; recruitment will be stratified by sex and limited to 60-70% for either sex.

2. Screen positive for one of the three clinical "sensitizing" questions, intended to identify potential palliative care (PC) needs:

   'Would I be surprised if this patient were to die within one year?'

   • A "No" response indicates possible palliative care needs. 'Has this patient experienced 'escalating care events' at least twice in the past year, including i) unscheduled hospitalizations for HF, ii) emergency department visits for HF, iii) visits to out-of-hours primary care services for HF, and/or iv) other similar escalating care events?'
   • A "Yes" response indicates possible PC needs. 'Is this patient experiencing persistent or worsening multidimensional symptoms (e.g., physical, psychological, social, or spiritual concerns) despite optimal HF treatment, such that a palliative assessment is indicated (upon discretion of the treating physician or nurse)?'
   • A "Yes" response indicates possible PC needs.

3. patient's or informal caregiver's ability to use technology (e.g., having internet access, owning a smartphone or tablet, or having someone available who can assist them).

4. capacity to provide informed consent.

Primary Caregiver:

1. Informal caregiver who is present with the patient during the implementation of the intervention
2. ≥18 years
3. capacity to provide consent.

Healthcare professionals: Two professionals identified by the consortium in each site, willing to be trained in the intervention to perform the feasibility study.

Exclusion Criteria:

1. Acute events leading to multiple outpatient visits not related to the HF diagnosis.
2. severe cognitive impairment or language disorders as determined by the attending healthcare professional based on clinical judgment and medical record review.
3. simultaneous participation in another study.
4. inability to read and write in the language in which the study is conducted.

Primary caregivers:

1. Cognitive impairment or language disorders determined by the attending healthcare professional.
2. inability to read and write in the language in which the study is conducted.

Health care professionals: a) Inability to read and write fluently in the language(s) required for the study site and for using the digital questionnaire.

Adults with a confirmed diagnosis of heart failure receiving outpatient care at Hospital de Granollers who are identified as having worsening symptoms and/or palliative care needs and are eligible to participate in the RAPHAEL feasibility study.