Outcomes of No-Touch Vs Conventionally Harvested Saphenous Veins for Coronary Artery Bypass Surgery: Individual Patient Data Meta-Analysis Protocol.

The effect of no-touch (NT) vs conventional (CON) saphenous vein graft (SVG) harvesting on SVG patency and clinical outcomes in coronary artery bypass remains unclear. Although prior trial-level meta-analyses have generally reported improved patency with NT SVG, outcomes show variability across studies, and evidence from 2 recent, larger multicentre randomized clinical trials is discordant. This individual patient data meta-analysis (IPDMA) will evaluate the impact of harvesting techniques on graft patency and clinical outcomes. A systematic literature search was conducted for randomized clinical trials comparing NT SVG and CON SVG. Studies were eligible if they included at least 1 year of follow-up evaluation with graft imaging. The primary efficacy outcome will be graft failure, defined as graft-level study SVG occlusion. The secondary outcomes will include leg wound complications, patient-level graft failure, graft malfunction (composite of graft occlusion or stenosis), and major adverse cardiac events (MACE) defined as the composite of all-cause death, myocardial infarction, or any repeat revascularization. A 2-stage IPDMA will be performed. In the first stage, mixed-effects logistic regression models will be fitted separately within each trial. In the second stage, trial-level estimates will be pooled using random-effects models to generate overall effects. Prespecified subgroup analyses will be conducted via a 2-stage framework to evaluate potential effect modification by key patient-level characteristics. This IPDMA will enable more robust evaluation of the effect of harvesting techniques on SVG patency and clinical outcomes, leveraging patient-level datasets for in-depth analyses, particularly among patient subgroups with distinct risk profiles.