Treatment expectations are a key mechanism of placebo effects in clinical trials. In a previous study (PSY-HEART-I), preoperative expectation optimisation improved quality of life 6 months postcardiac surgery. However, barriers such as travel distance, staffing shortages and COVID-19 limited participation. This study evaluates the feasibility and acceptability of iEXPECT, a brief internet-based intervention designed to optimise expectations before heart surgery.

In this three-arm, multicentre randomised controlled trial, 160 patients undergoing elective coronary artery bypass graft surgery are randomised to: (a) standard of care (SOC); (b) SOC plus iEXPECT with phone-based guidance (iEXPECT enhanced) or (c) SOC plus iEXPECT with email-based guidance (iEXPECT limited). The intervention includes four 20 min online modules addressing surgical benefits, side effects and coping strategies. Modules are accompanied by personalised guidance provided through feedback on each module via email or telephone (three before surgery, three booster sessions at 6, 12 and 18 weeks postsurgery). Assessments occur at baseline (5–21 days before surgery), preoperatively (day before surgery), 7 days postsurgery and 6 months later. Primary feasibility outcomes include recruitment (≥1 participant/week/centre), retention (≥49% completing 6-month follow-up including biomarkers) and engagement (≥75% completing ≥1 presurgery module). Acceptability is measured by self-reported enjoyment, usefulness and impact, with acceptance defined as mean scores >3.4 (5-point Likert scale) and CSQ-I ratings. Secondary outcomes include psychological measures, inflammatory markers and heart rate variability.

Ethical approval was granted by the Ethics Committees of Philipps University Marburg (AZ 229/23 BO) and the University of Giessen (AZ 186/23). All participants provide written informed consent. Results will be shared via publications, conferences and public outreach with relevant consumer advocacy groups.

DRKS00033284.