This study evaluates the effectiveness of an innovative care approach that integrates face-to-face education, motivational counseling, and mobile health (mHealth) support delivered via the LINE application among Thai older adults following acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI). The intervention aims to support post-discharge recovery by promoting healthy behaviors, improving health status, and enhancing patient satisfaction with care.

The primary objective is to assess the effect of the intervention on patient-reported outcomes, including healthy behaviors, health status, and patient satisfaction. Secondary objectives include evaluating unplanned hospital visits during a 12-week follow-up period and exploring participants' experiences, motivation, and engagement with the innovative care approach.

This is a single-site, mixed-methods experimental study designed to evaluate the effectiveness of an innovative care approach among older adults following acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI). The intervention integrates structured face-to-face education and skill-building sessions, individualized motivational counseling, and mobile health (mHealth) support delivered via the LINE application.

The quantitative component is a parallel-group, superiority randomized controlled trial with repeated measures. Eighty participants will be enrolled and randomly assigned in a 1:1 ratio to either the intervention group (innovative nurse-led care approach) or the control group (usual post-ACS care). Randomization will occur after baseline assessment using a computer-generated sequence with allocation concealment, and analyses will follow the intention-to-treat principle.

The intervention will be delivered over a 12-week period. Quantitative assessments of patient-reported outcomes will be conducted at baseline, week 8, and week 12. The qualitative component will use a post-intervention descriptive design, with in-depth interviews conducted between weeks 13 and 16 among a subset of intervention participants to explore experiences, perceived benefits, motivation, and engagement. A sequential explanatory mixed-methods approach will be used to contextualize quantitative findings with qualitative insights.

Quantitative data will be analyzed using descriptive statistics and generalized estimating equations to assess longitudinal changes over time and between groups. Unplanned hospital visits during the follow-up period will be analyzed using appropriate regression models for count data. Qualitative data will be analyzed using thematic analysis, and integration of findings will occur during interpretation.

The study has received institutional ethics approval. Written informed consent will be obtained from all participants, and confidentiality and data security will be maintained throughout the study.

Inclusion Criteria:

Inclusion Criteria for the quantitative phase:

1. Aged ≥ 60 years old.
2. Diagnosed with ACS and received PCI within 3-12 months.
3. Being familiar with using a smartphone or tablet with the LINE application, either personally or through a caregiver or family member.
4. No cognitive impairment assessed by the 6-Item Cognitive Function Test-Thai Version (6CIT), score less than 8.
5. Able to communicate in the Thai language by speaking, listening, reading, and writing in Thai sufficiently.
6. Voluntarily agreed to participate and has signed the informed consent form.

Inclusion Criteria for the qualitative phase:

1. Participate in the experimental group and complete the program.
2. Extreme case sampling involves selecting the top 6 highest and top 6 lowest scores for healthy behavior.
3. Willing to participate in a one-on-one in-depth interview.

Exclusion Criteria:

Exclusion Criteria for the quantitative phase:

1. Have clinical contraindications to physical exercise (i.e. unstable angina, uncontrolled arrhythmias, systolic >180 mmHg or diastolic >110 mmHg, an LVEF of less than 40%, recent major surgery within 12 weeks such as CABG, valve replacement, or orthopedic surgery), or any serious medical condition that the cardiologist considers unsafe to perform physical activity.
2. Visual or hearing impairments that cannot be adequately managed with medical devices (e.g., eyeglasses or hearing aids) and that interfere with the ability to participate in study activities or communicate effectively.

Individual participant data will not be shared. Study findings will be reported in aggregate form only, in accordance with institutional review board approval and participant consent.

This study will be a single-blind randomized controlled trial. The independent statistician, who will generate the randomization sequence, and outcome assessors will be blinded to group allocation to minimize assessment bias when collecting and analyzing patient-reported outcomes and hospital visit data.