Saphenous Vein de Novo - SAVED

Description:

Stenting vs. PTCA for angiographic restenosis in vein grafts.

Hypothesis:

To compare stent implantation with balloon angioplasty for the treatment of obstructive disease of venous bypass grafts.

Study Design

Study Design:

Patients Screened: Not given
Patients Enrolled: 220
Mean Follow Up: 240 days
Mean Patient Age: 66
Female: 19

Patient Populations:

New lesions in aortocoronary venous bypass grafts
Angina pectoris, objective evidence of myocardial ischemia, or both
Stenosis of 60 percent or more of the luminal diameter
Vessels from 3.0 to 5.0 mm in diameter

Exclusions:

Myocardial infarction within the previous seven days
Contraindication to aspirin, dipyridamole, or warfarin
Ejection fraction less than 25 percent
Diffuse disease that would require more than two stents
Evidence of thrombus
Outflow obstruction of the graft due to distal anastomotic stenosis or poor runoff in the recipient native vessel

Primary Endpoints:

Angiographic restenosis, defined as stenosis of 50 percent or more of the luminal diameter at follow-up.

Secondary Endpoints:

Rate of procedural success
Change in the minimal luminal diameter from the baseline value immediately after the procedure and at six months
Duration of hospitalization
Frequency of bleeding and peripheral vascular complications

Drug/Procedures Used:

Palmaz-Schatz coronary stent vs balloon angioplasty

Concomitant Medications:

Patients assigned to stent placement received aspirin (325 mg qd) and dipyridamole (75 mg tid), beginning at least 24 hours before the procedure. During the procedure, patients received intravenous dextran 40 and heparin to maintain an activated clotting time of more than 300 seconds. Warfarin therapy was begun on the day of the procedure, and heparin therapy was continued until a therapeutic prothrombin time (international normalized ratio, 2.0 to 3.5) was achieved. Dipyridamole and warfarin were continued for one month, and aspirin indefinitely.

Principal Findings:

220 patients were enrolled; 110 patients were assigned to stent placement and 110 patients to angioplasty. After randomization, five patients (two in the stent group and three in the angioplasty group) were excluded because of violations of the protocol with respect to enrollment criteria.

Patients assigned to stenting had a higher rate of procedural efficacy, (92 percent vs. 69 percent, P<0.001) compared to angioplasty.

Patients in the stent group had a larger mean (+/-SD) increase in luminal diameter immediately after the procedure (1.92+/-0.30 mm vs 1.21+/-0.37 mm, p < 0.001) and a greater mean net gain in luminal diameter at six months (0.85+/-0.96 vs. 0.54+/-0.91 mm, P = 0.002).

Hemorrhagic complications were more frequent among stented patients compared to controls (17 percent vs. 5 percent, P<0.01).

Restenosis occurred in 37 percent of the patients in the stent group and in 46 percent of the patients in the angioplasty group (P = 0.24).

At 240 days, freedom from death, myocardial infarction, repeat bypass surgery, or revascularization of the target lesion was significantly better in the stent group (73 percent vs. 58 percent, P = 0.03). The relative risk of a major cardiac event associated with stenting was 0.82 (95 percent confidence interval, 0.68 to 0.98)

Conclusions: As compared with balloon angioplasty, stenting of selected venous bypass-graft lesions resulted in superior procedural outcomes, a larger gain in luminal diameter, and a reduction in major cardiac events.

Interpretation:

Stent placement in new vein-graft lesions was associated with better initial angiographic results and higher rates of procedural success. Although the luminal diameter at six months was larger in the stent group, there was no significant difference in the rate of restenosis, the primary angiographic end point. Major cardiac events occurred less frequently in the stent group. These favorable results are encouraging for lesions which have been difficult to treat by other new technologies.

References:

1. N Engl J Med 1997;337:740-7. Final results

Clinical Topics: Invasive Cardiovascular Angiography and Intervention

Keywords: Risk, Myocardial Infarction, Coronary Disease, Confidence Intervals, Angioplasty, Balloon, Coronary, Stents


< Back to Listings