Surgery versus conservative management for severe pectus excavatum (RESTORE): protocol for a multicentre, randomised, controlled superiority trial.

INTRODUCTION: Severe pectus excavatum (PE) may impair cardiopulmonary and physical function. The effectiveness of surgical treatment to correct PE and restore physical function is widely debated due to a lack of high-quality comparative evidence. The RESTORE trial aims to determine the clinical and cost-effectiveness of corrective surgery for severe PE compared with conservative management for the first time in a randomised controlled trial (RCT). METHODS AND ANALYSIS: RESTORE is a pragmatic, multicentre, RCT with an embedded observational cohort. 200 participants aged ≥12 years with severe PE will be recruited at around 12 National Health Service cardiothoracic surgical centres in England. Participants will be randomised 1:1 to receive either surgery within 3 months of randomisation (intervention arm) or no surgery until after the primary outcome measurement at 1 year (comparator arm). The primary outcome is change in physical functioning from baseline to 1 year as measured by the Short Form Health Survey (SF-36v2) physical function score. The primary economic outcome is cost-effectiveness. The key secondary outcome is change in % predicted VO2peak at 1 year measured by cardiopulmonary exercise test (CPET). Outcomes will be assessed at 1 year post-randomisation in the comparator arm and 1 year post-surgery in the intervention arm. The primary analyses will be undertaken on an intention-to-treat population using a linear mixed-effects model, adjusted for stratification variables via a binary covariate. Other secondary outcomes will include change from baseline of cardiopulmonary function (CPET and spirometry), health-related quality of life using the EuroQol 5 Dimension 5 Level (EQ-5D-5L) and SF-36v2 questionnaires, Hospital Anxiety and Depression Scale and disease specific symptoms (Phoenix Comprehensive Assessment for Pectus Excavatum Symptoms and Pectus Excavatum Evaluation Questionnaire). Adverse events, complications from surgery and operative technical success (Haller and Compression Indices from preoperative and postoperative CT scans) will also be assessed. Health economic analysis will estimate the incremental cost per quality adjusted life year at 1 year. ETHICS AND DISSEMINATION: The trial was approved by East of Scotland Research and Ethics Service (24/ES/0034). Participants who are ≥16 years of age will be required to provide written informed consent. For participants <16 years of age who are not judged to be Gillick competent, written assent and written informed consent from a parent/guardian will be required. Results will be submitted for publication in peer-reviewed journals and shared with participants, clinicians and commissioners. TRIAL REGISTRATION NUMBER: ISRCTN11359779.