Elsevier

American Heart Journal

Volume 246, April 2022, Pages 12-20
American Heart Journal

Trial Designs
Rationale and design of a randomized trial evaluating an external support device for saphenous vein coronary grafts

https://doi.org/10.1016/j.ahj.2021.12.009Get rights and content

Background

Coronary artery bypass grafting (CABG) is the most common revascularization approach for the treatment of multi-vessel coronary artery disease. While the internal mammary artery is nearly universally used to bypass the left anterior descending coronary artery, autologous saphenous vein grafts (SVGs) are still the most frequently used conduits to grafts the remaining coronary artery targets. Long-term failure of these grafts, however, continues to limit the benefits of surgery.

Methods

The Cardiothoracic Surgical Trials Network trial of the safety and effectiveness of a Venous External Support (VEST) device is a randomized, multicenter, within-patient trial comparing VEST-supported versus unsupported saphenous vein grafts in patients undergoing CABG. Key inclusion criteria are the need for CABG with a planned internal mammary artery to the left anterior descending and two or more saphenous vein grafts to other coronary arteries. The primary efficacy endpoint of the trial is SVG intimal hyperplasia (plaque + media) area assessed by intravascular ultrasound at 12 months post randomization. Occluded grafts are accounted for in the analysis of the primary endpoint. Secondary confirmatory endpoints are lumen diameter uniformity and graft failure (>50% stenosis) assessed by coronary angiography at 12 months. The safety endpoints are the occurrence of major adverse cardiac and cerebrovascular events and hospitalization within 5 years from randomization.

Conclusions

The results of the VEST trial will determine whether the VEST device can safely limit SVG intimal hyperplasia in patients undergoing CABG as treatment for coronary atherosclerotic disease.

Section snippets

Shortcomings of saphenous vein coronary grafts

Coronary artery bypass grafting (CABG) is the optimal treatment of multi-vessel coronary artery disease.1 While the internal mammary artery is universally used to bypass the left anterior descending (LAD) coronary artery and other arterial grafts are increasingly being used,2 autologous saphenous vein grafts (SVGs) are still the secondary bypass conduits of choice. To date, progressive failure of SVGs remains the major shortcoming of CABG surgery.3,4 Approximately 25% of SVGs occlude within 1

Study design

The design of the VEST randomized trial, which is currently ongoing, is a within-patient, open label study of the safety and effectiveness of the VEST device. It is an industry-funded, pivotal clinical trial, leveraging the infrastructure of the NHLBI-supported Cardiothoracic Surgery Trials Network. The trial compares SVGs with and without VEST support in 224 patients undergoing isolated CABG at 17 highly experienced clinical centers in the U.S. and Canada. The planned enrollment period was 12

Funding

This trial was funded by Vascular Graft Solutions Ltd (Tel Aviv, Israel) and conducted by investigators within the Cardiothoracic Surgical Trials Network (CTSN).

Declarations of interest

Dr Puskas reports consultation agreements with Medtronic and Scanlan, outside the submitted work. Dr Alexander reports institutional research support from Bayer, Bristol-Myers Squibb, CryoLife, CSL Behring, Ferring, US Food and Drug Administration, Glaxosmithkline, Humacyte, US National Institutes of Health, and XaTek; he receives consultant and honoraria payments from AbbVie, Akros, Atricure, Bristol-Myers Squibb, CryoLife, Ferring, Glaxosmithkline, Janssen, Pfizer, Portola, and US Veterans

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  • Cited by (1)

    • Intimal hyperplasia, saphenous vein graft disease, and clinical outcomes: Insights from the CTSN VEST randomized trial

      2022, Journal of Thoracic and Cardiovascular Surgery
      Citation Excerpt :

      The trial was conducted under an Investigational Device Exemption application. Details of the study design and results for the primary outcome have been reported previously.13,14 Patients with multivessel atherosclerotic coronary artery disease scheduled to undergo CABG were enrolled.

    This paper was handled by Guest Editor (Charles Maynard, PhD)

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