Clinical trial NCT00187356: Multicentre Radial Artery Patency Study: Results of Patency Beyond 5 Years After Coronary Artery Bypass Surgery
Official title: Multicentre Radial Artery Patency Study: Results of Patency Beyond 5 Years After Coronary Artery Bypass Surgery
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: Coronary Artery Disease
Keywords: Coronary Bypass Surgery
Coronary Artery Disease
Angiography
Arterial Grafts
Radial Artery
Saphenous Vein
Lead sponsor: Sunnybrook Health Sciences Centre
Sponsor class: OTHER
Collaborators: name: Canadian Institutes of Health Research (CIHR)
First posted: 2005-09-16
Enrollment: 269
Sex: ALL
Minimum age (years): 30
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: Bypass surgery is often required to treat severe coronary heart disease. Either arteries or veins can be used as bypass grafts. We wish to compare the long-term durability of the saphenous vein from the leg to that of the radial artery from the fore-arm when used as bypass grafts. We are examining how many of these grafts are still functioning beyond 5 years after bypass surgery by performing a coronary angiogram. After 1-year, we found that radial arteries were more likely to be functioning than saphenous veins. We hypothesize that radial arteries will continue to be superior beyond 5 years.

Detailed description: The multi-centre Radial Artery Patency Study, (RAPS) is a series of longitudinal graft patency studies designed to compare the long-term patency of the radial artery to the saphenous vein. Between 1996 and 2001, 561 patients were intraoperatively randomized to undergo surgery according to one of two strategies: radial-artery grafting to the circumflex territory and saphenous-vein grafting to the right coronary artery or radial-artery grafting to the right coronary artery and saphenous-vein grafting to the circumflex territory. The first study compared the 8-12 month angiographic patency of the radial artery with that of the saphenous vein as a conduit for coronary artery bypass and found that radial arteries were superior. The primary objective of this current study is to determine the beyond 5-year angiographic patency of the radial artery compared with a saphenous vein coronary bypass graft.

HYPOTHESES

1. The angiographic patency of radial artery grafts studied beyond 5 years following surgery exceeds that of saphenous vein grafts.
2. Radial artery conduits studied beyond 5 years postoperatively have less graft disease than saphenous veins.

SAMPLE SIZE We expect to study 350 patients, which will allow us to test for a 35% risk reduction from 23% occlusion rate in saphenous veins to 15% in radial arteries, assuming a 5% within-patient correlation, with 80% power for a 2-tailed alpha of 0.05.

Eligibility criteria: Inclusion Criteria:

The patient population consists of patients who were enroled into the original Multicentre Radial Artery Patency Study between November 1996 and January 2001. These included patients undergoing isolated coronary artery bypass surgery less than 80 years of age with 3 vessel coronary disease and left ventricular ejection fraction greater than 35%.

Exclusion Criteria:

Exclusion criteria included 1: Inability to use the radial artery or saphenous vein conduits: a)nonpalpable ulnar arteries or a positive Allen's test, b) an abnormal Doppler study or ultrasonographic study of the arms, c) a history of vasculitis or Raynaud's syndrome, bilateral varicose veins or vein stripping. 2: Conditions that affected the safety of follow-up angiography: a)renal insufficiency (creatinine \> 180 umol/L) b)severe peripheral vascular disease precluding femoral access b)coagulopathy or obligatory uninterrupted use of anticoagulants c) known allergy to radiographic contrast media d) women of childbearing potential e) comorbid illness which precludes the use of follow up angiography f) geographically inaccessible for follow up angiography.

Primary outcomes:
measure: The primary endpoint will be the proportion of grafts which are functionally occluded (TIMI flow 0, 1, or 2).
timeFrame: Beyond 5 years after bypass urgery
Secondary outcomes:
measure: a) the proportion of occluded study grafts (TIMI 0)
timeFrame: Beyond 5 years after bypass urgery
measure: b) the proportion of functionally occluded grafts where proximal stenosis of native vessel is <90% vs >90%
timeFrame: Beyond 5 years after bypass urgery
measure: c) the proportion of completely occluded grafts where proximal stenosis of native vessel is <90% vs >90%
timeFrame: Beyond 5 years after bypass urgery
measure: d) proportion of study grafts with string sign
timeFrame: Beyond 5 years after bypass urgery
Other outcomes:
Locations:
city: Edmonton
country: Canada
facility: University of Alberta
state: Alberta
city: Winnipeg
country: Canada
facility: Manitoba Health Sciences Centre
state: Manitoba
city: London
country: Canada
facility: London Health Sciences Centre - UC
state: Ontario
city: London
country: Canada
facility: London Health Sciences Centre - VC
state: Ontario
city: Ottawa
country: Canada
facility: Ottawa Heart Institute
state: Ontario
city: Toronto
country: Canada
facility: Sunnybrook and Women's College HSC
state: Ontario
city: Toronto
country: Canada
facility: St. Michael's Hospital
state: Ontario
city: Toronto
country: Canada
facility: Toronto General Hospital
state: Ontario
city: Vancouver
country: Canada
facility: Vancouver General Hospital
state: Ontario
city: Laval
country: Canada
facility: Laval Hospital
state: Quebec
city: Montreal
country: Canada
facility: Montreal Heart Institute
state: Quebec
city: Montreal
country: Canada
facility: Montreal Jewish General Hospital
state: Quebec
city: Hamilton
country: New Zealand
facility: Waikato Hospital
Study officials:
affiliation: Sunnybrook Health Sciences Centre
name: Stephen E Fremes, MD
role: STUDY_CHAIR
References:
citation: Fremes SE. Multicenter radial artery patency study (RAPS). Study design. Control Clin Trials. 2000 Aug;21(4):397-413. doi: 10.1016/s0197-2456(00)00059-3.
citation: Desai ND, Cohen EA, Naylor CD, Fremes SE; Radial Artery Patency Study Investigators. A randomized comparison of radial-artery and saphenous-vein coronary bypass grafts. N Engl J Med. 2004 Nov 25;351(22):2302-9. doi: 10.1056/NEJMoa040982.
citation: Deb S, Cohen EA, Singh SK, Une D, Laupacis A, Fremes SE; RAPS Investigators. Radial artery and saphenous vein patency more than 5 years after coronary artery bypass surgery: results from RAPS (Radial Artery Patency Study). J Am Coll Cardiol. 2012 Jul 3;60(1):28-35. doi: 10.1016/j.jacc.2012.03.037.
citation: Tam DY, Deb S, Nguyen B, Ko DT, Karkhanis R, Moussa F, Fremes J, Cohen EA, Radhakrishnan S, Fremes SE. The radial artery is protective in women and men following coronary artery bypass grafting-a substudy of the radial artery patency study. Ann Cardiothorac Surg. 2018 Jul;7(4):492-499. doi: 10.21037/acs.2018.05.19.
citation: Deb S, Singh SK, Moussa F, Tsubota H, Une D, Kiss A, Tomlinson G, Afshar M, Sless R, Cohen EA, Radhakrishnan S, Dubbin J, Schwartz L, Fremes SE; Radial Artery Patency Study Investigators. The long-term impact of diabetes on graft patency after coronary artery bypass grafting surgery: a substudy of the multicenter Radial Artery Patency Study. J Thorac Cardiovasc Surg. 2014 Oct;148(4):1246-53; discussion 1253. doi: 10.1016/j.jtcvs.2014.06.057. Epub 2014 Jul 17.
citation: Yanagawa B, Algarni KD, Singh SK, Deb S, Vincent J, Elituv R, Desai ND, Rajamani K, McManus BM, Liu PP, Cohen EA, Radhakrishnan S, Dubbin JD, Schwartz L, Fremes SE. Clinical, biochemical, and genetic predictors of coronary artery bypass graft failure. J Thorac Cardiovasc Surg. 2014 Aug;148(2):515-520.e2. doi: 10.1016/j.jtcvs.2013.10.011. Epub 2013 Dec 9.