Radial Artery Versus Saphenous Vein Patency (RSVP) Study (RSVP)

A Randomised Controlled Trial to Compare Angiographic Patency of Radial Artery Versus Saphenous Vein Used as Free Aorto-coronary Grafts in Coronary Revascularization

The Royal College of Surgeons of England, Royal Brompton & Harefield NHS Foundation Trust, National Heart Foundation, Australia, Victor Phillip Dahdaleh Charitable Foundation

The purpose of this study is to determine whether the radial artery (artery in the arm) or saphenous vein (vein in the leg), when used as bypass grafts for coronary artery bypass surgery, have a greater patency rate (degree of opening)at 5 years after surgery.

Arteries differ from veins both in morphology and physiology. Thus the way they behave as in vivo conduits when used in coronary artery bypass grafting is also likely to be different. This may partly explain the predisposition of veins used as coronary conduits to accelerated atherosclerosis in comparison with the internal mammary artery grafts. There are presently few data describing the properties of the radial artery as an in-vivo coronary conduit over the longer-term. The study will compare angiographic patency of the radial artery or saphenous vein graft anastomosed to the native left circumflex coronary territory at 3 months and 5 years after surgery. A substudy will compare 5-year post-surgery diameter and blood flow of in-vivo radial artery and saphenous vein grafts in response to endothelium-dependent and non-endothelium-dependent stimuli when patients attend for their scheduled follow-up angiogram.

Patients were randomized to receive either a radial artery or a long saphenous vein graft to the left circumflex coronary artery territory during CABG surgery

Diameter response of the study vessel (saphenous vein or radial artery graft) to acetylcholine, measured using quantitative coronary angiography from the coronary angiogram.

Graft flow response to acetylcholine, calculated from vessel diameter using quantitative coronary angiography, and velocity using an intragraft Doppler wire.

Inclusion Criteria: on waiting list for clinically-indicated myocardial revascularization surgery aged 40-70 years significant stenosis (≥70%) in the circumflex territory as identified on preoperative angiograms negative Allen's test (defined as the return of palmar circulation within 5 seconds of releasing ulnar artery compression) willing to give written informed consent Exclusion Criteria: poor left ventricular (LV) function (LV ejection fraction <25%) severe diffuse peripheral vascular disease or bilateral varicose venous disease inability to comply with the angiographic follow-up at 3 months or/and 5 years

Collins P, Webb CM, Chong CF, Moat NE; Radial Artery Versus Saphenous Vein Patency (RSVP) Trial Investigators. Radial artery versus saphenous vein patency randomized trial: five-year angiographic follow-up. Circulation. 2008 Jun 3;117(22):2859-64. doi: 10.1161/CIRCULATIONAHA.107.736215. Epub 2008 May 27.

Chong WC, Collins P, Webb CM, De Souza AC, Pepper JR, Hayward CS, Moat NE. Comparison of flow characteristics and vascular reactivity of radial artery and long saphenous vein grafts [NCT00139399]. J Cardiothorac Surg. 2006 Mar 3;1:4. doi: 10.1186/1749-8090-1-4.

Webb CM, Moat NE, Chong CF, Collins P. Vascular reactivity and flow characteristics of radial artery and long saphenous vein coronary bypass grafts: a 5-year follow-up. Circulation. 2010 Aug 31;122(9):861-7. doi: 10.1161/CIRCULATIONAHA.109.887000. Epub 2010 Aug 16.