Purpose: Vein graft failure has been attributed to increased pressure in the venous conduit. Previous animal studies have demonstrated that external support for these grafts have resulted in a reduction in neointimal formation and graft thickening. This study aims to show safety and potential improvement to vein graft patency when covered with a flexible external wire device.
Methods: This is a 3 center randomized study with the use of the external supporting device to either the circumflex or right coronary artery system. Thirty patients were successfully recruited for the study. All saphenous veins were harvested with an open technique and surgery performed with cardiopulmonary bypass (CPB). Flow measurements were recorded in all vein grafts after discontinuation of CPB. ECG and CK-MB were recorded pre- and postoperatively. Patients were reviewed at 6 weeks, 6 months, and planned coronary angiography at 12 months to assess vein graft patency with OCT and IVUS.
Results: All 30 patients underwent an uneventful CABG operation. Th e device was successfully deployed to the randomized vessel. Mean patient age was 64 ± 8 yrs, left ventricular ejection fraction 56 ± 9%, and logistic euroscore 1.83 ± 1.18. Mean cross clamp and bypass times were 00:59 ± 00:18 and 01:42 ± 00:26, respectively; final TTFM fl ow 67 ± 28 ml/min and pulsatility index 2.24 ± 1.11. Mortality was 0%. Four patients had SAEs but these were unrelated to placement of the external mesh. Length of hospital stay was 7 ± 2 days. Patients are planned to undergo coronary angiography from November 2012.
Conclusions: This study has demonstrated the feasibility of deploying this device to vein grafts in the circumflex and right coronary territory without an increase in mortality or morbidity, and with acceptable cross clamp and bypass times and length of hospital stay.