VA patients with coronary artery disease and who have agreed to undergo coronary artery bypass graft surgery would be randomized to receive either radial artery or saphenous vein to the study vessel. The primary outcome variable is graft patency at one year.

Radial Artery Versus Saphenous Vein Grafts in Coronary Artery Bypass Surgery

Cardiovascular Disease

Coronary Artery Disease

Primary Hypothesis:

Radial artery grafts will have a higher graft patency rate at one year after coronary artery bypass graft surgery (CABG) compared to saphenous vein grafts.

Secondary Hypotheses:

Determine if there are any differences in clinical outcomes, cost and quality of life in patients receiving radial artery versus saphenous vein grafts.

Intervention: 1) Saphenous vein graft. This is the standard conduit for coronary artery bypass grafting to all areas of the heart except the left anterior descending (LAD) artery. 2) Radial artery. This is the experimental conduit. Preference should be given to harvesting from the non-dominant arm.

Primary Outcomes: 1-year post CABG surgery patency rates

Study Abstract:

Although the radial artery was introduced as a potential conduit for coronary artery bypass grafting in the 1970s, enthusiasm for its use was limited by the technical difficulty of harvesting the vessel and problems with perioperative vascular spasm. In spite of this, some surgeons persisted based on their belief that arterial conduits would be better than vein grafts, in terms of long-term patency. With the development of new harvesting techniques and the introduction of calcium channel blockers to prevent vasospasm, the use of the radial artery graft has increased in recent years. This use of the radial artery as a conduit is not based on any long-term prospective data regarding its patency. However, because the VA has been a leader in defining the long-term efficacy/patency of saphenous vein and internal mammary grafts, it is appropriate for the VA to investigate radial artery grafts. In fact, the VA under its Cooperative Studies Program, is probably the only health care delivery system that has the ability to undertake this study.

Study Design:

The study is a prospective, randomized, unblinded clinical trial. The population consists of VA patients with coronary artery disease documented by coronary arteriography and who have agreed to undergo coronary artery bypass surgery. Medical conditions which could affect blood flow through the patient's arm are the main exclusion criteria. These include Raynaud's symptoms, positive Allen test, neurologic or musculoskeletal disease affecting the arm and patients with one arm.

Patients who are eligible and agree to participate in the study will be randomly assigned to receive one radial artery graft or one saphenous vein graft to the following vessels: left anterior descending if internal mammary not used, circumflex, diagonal, and right coronary artery. The surgeon will determine the subject vessel preoperatively by selecting the vessel that is suitable for grafting.

The stratification factors will be the participating hospital and which vessel is to be bypassed, left anterior descending versus all other vessels.

History, physical examination, laboratory tests, and cardiac catheterization will be performed at baseline and at one year. Follow-up clinic visits will be at two weeks, three, six, and nine months post CABG. Coronary angiography will be performed one week and one year post surgery. Quality of life and hand/leg functional status will be assessed at baseline, three months, and one year. Cost measures will be captured.

Biostatistical Considerations:

For this trial, a sample size of 874 randomized patients will be required. This will provide 90% power to detect a difference in one-year patency rates of 92% for the radial artery versus 83% for the saphenous vein and an expected one-year catheter completion rate of 65%.

This is a five year study. There will be four years of patient accrual and one year of follow-up. Nine participating VA medical centers will be expected to randomize two patients per month.

saphenous vein graft

radial artery graft

CSP #474 - Radial Artery vs. Saphenous Vein Grafts in Coronary Artery Bypass Surgery (Radial Artery)

The primary end point was angiographic graft patency at 1 year after coronary artery bypass surgery, defined as any opacification of distal target by injection of the graft. The window for the 1-year angiogram was 2 to 24 months. This window was chosen to capture early clinically indicated angiograms and late selective angiograms in patients who did not have symptoms. Study grafts that were occluded at 1 week after coronary artery bypass graft surgery were considered occluded at 1 year. One-year graft patency data were missing if patients whose study grafts were patent at 1 week did not undergo an angiogram within the time window or if the central angiography laboratory was not able to determine graft patency.

VA Medical Center, Birmingham

Southern Arizona VA Health Care System

Central Arkansas VHS Eugene J. Towbin Healthcare Ctr, Little Rock

Edward Hines, Jr. VA Hospital

Southeast Veterans Healthcare System, New Orleans

VA Boston Healthcare System, Brockton Campus

VA Ann Arbor Healthcare System

VA Medical Center, Minneapolis

New Mexico VA Health Care System, Albuquerque

Michael E. DeBakey VA Medical Center (152)

Hunter Holmes McGuire VA Medical Center

The verbatim description was used to classify events by Body System affected (System Organ Class or SOC) and to group using a common medical term (Preferred Term or PT).

Saphenous Vein Graft

saphenous vein graft: Saphenous vein harvested from the arm is used as a conduit for CABG.

Arm 1

Radial Artery

radial artery graft: Radial artery harvested from the arm is used as a conduit for CABG.

Arm 2

Saphenous Vein Graft

saphenous vein graft : Saphenous vein harvested from the arm is used as a conduit for CABG.

Saphenous Vein Graft

Radial Artery

radial artery graft : Radial artery harvested from the arm is used as a conduit for CABG.

Radial Artery Graft

Total

Age, Continuous

Sex: Female, Male

White

Black or African American

Other

Did not specify

Race classification was based on prespecified categories and obtained from the patient. One patient did not specify race.

Race/Ethnicity, Customized

Missing

Represents increasing angina from minimal (I) to severe incapacitating angina (IV).

Canadian Functional Class

Left Anterior Descending

Circumflex

Right Coronary Artery

Target Vessel

Diabetes mellitus

Hypertension

Heart Failure

Participants may have more than one comorbidity.

Comorbidities

Previous Myocardial Infarction

No Previous Myocardial Infarction

Represents the number of patients who had a previous myocardial infarction.

Never smoked

Ex-smoker

Current smoker

Missing data

Smoking History

Total cholesterol level was missing for 26 patients in the saphenous vein (SV) group and 12 patients in the radial artery (RA) group.

Total Cholesterol

HDL level was missing for 34 SV patients and 19 RA patients.

LDL level missing for 43 SV and 31 RA patients

Triglycerides level missing for 33 SV and 18 RA patients.

Triglycerides

There was more disease in the radial artery grafts at 1 week and at 1 year. There is more spasm or string sign in radial artery grafts. Study was conducted predominantly in men. Data show lower vein graft patency when endoscopic harvesting was used.

Steven Goldman, MD

The study was designed to have 90% power to detect 1-year patency rates of 92% in radial artery vs 83% in saphenous vein grafts, with a 2-sided type I error of 5%and an expected 1-year catheterization completion rate of 65%.

All analyses were performed according to intention to treat. The study was designed to have 90%power to detect 1-year patency rates of 92% in radial artery vs 83% in saphenous vein grafts, with a 2-sided type I error of 5% and an expected 1-year catheterization completion rate of 65%. .

To Compare 1-year Angiographic Patency of Radial Artery Grafts Versus Saphenous Vein Grafts in Patients Undergoing Elective Coronary Artery Bypass Graft (CABG) Surgery.

Radial Artery Grafts

radial artery graft: Radial artery harvested from the arm is used as a conduit for CABG.

Radial Artery Grafts

Death

Myocardial Infarction

Stroke

Radial Artery Graft

radial artery graft : Radial artery harvested from the arm is used as a conduit for CABG.

Radial Artery Versus Saphenous Vein Grafts in Coronary Artery Bypass Surgery

About this trial

Study ID

Status

Type

Phase

Placebo

Accepting

Trial Timing

What is this trial about?

What are the participation requirements?