Fig. 1

PRISMA flow diagram of the screening and selection of trials. a Different type of exercise or surgical intervention as comparator. b We were unable to assess the eligibility of one trial published as a conference abstract as the author did not respond to repeated email inquiries. Two other conference abstracts described trials with outcomes eligible for inclusion; however, these could not be included as authors were not yet ready to share their results. One further abstract was eligible for inclusion; however, the author failed to respond to requests for data (abstract references in Additional file 1: Appendix S3). c One of these trials was later excluded and one included. CAD coronary artery disease, RCT randomised controlled trial