A Study Comparing Vein Integrity and Clinical Outcomes (VICO) in Open Vein Harvesting and Two Types of Endoscopic Vein Harvesting for Coronary Artery Bypass Grafting: The VICO Randomised Clinical Trial
Background—Current consensus statements maintain that endoscopic vein harvesting (EVH) should be standard care in coronary artery bypass surgery (CABG) but vein quality and clinical outcomes have been questioned. The Vein Integrity and Clinical Outcome (VICO) trial was designed to assess the impact of different vein harvesting methods on vessel damage and if this contributes to clinical outcomes following CABG.
Methods—A single centre, randomised clinical trial of patients undergoing CABG with an internal mammary artery, and with one to four vein grafts were recruited. All the veins were harvested by a single experienced practitioner. We randomly allocated n=300 patients into: closed tunnel CO2 EVH (CT-EVH) (n=100), open tunnel CO2 EVH (OT-EVH) (n=100) and traditional open vein harvesting (OVH) (n=100) groups. The primary end-point was endothelial integrity and muscular damages of the harvested vein. Secondary end-points included clinical outcomes (major adverse cardiac events, MACE), use of healthcare resources and impact on health status (quality-adjusted life years, QALYs).
Results—The OVH group demonstrated marginally better endothelial integrity in random samples (85% vs. 88% vs. 93% for CT-EVH, OT-EVH and OVH, p<0.001). CT-EVH displayed the lowest longitudinal hypertrophy (1% vs. 13.5% vs. 3%, p=0.001). However, no differences in endothelial stretching were observed between groups (37% vs. 37% vs. 31%, p=0.62). Secondary clinical outcomes demonstrated no significant differences in composite MACE scores at each time point up to 48 months. The QALY gain per patient was: 0.11 (p<0.001) for closed tunnel CO2 EVH and 0.07 (p=0.003) for open tunnel CO2 EVH compared with open vein harvesting. The likelihood of being cost-effective, at a pre-defined threshold of £20,000 per QALY gained was: 75% for closed tunnel, 19% for open tunnel and 6% for open vein harvesting.
Conclusions—Our study demonstrates that harvesting techniques do impact upon integrity of different vein layers, albeit with only a small effect. Secondary outcomes suggest that histological findings do not directly contribute to MACE outcomes. Gains in health status were observed and cost-effectiveness was better with CT-EVH. High level experience with endoscopic harvesting performed by a dedicated specialist practitioner gives optimal results which is comparable to open vein harvesting.
Clinical Trial Registration—— URL: https://www.isrctn.com Unique Identifier: ISRCTN: 91485426
- Endoscopic vein harvesting
- Coronary artery bypass surgery
- Open vein harvesting
- coronary artery bypass graft
- Received March 7, 2017.
- Revision received May 22, 2017.
- Accepted June 12, 2017.