STents IN Grafts - STING

Description:

The goal of this trial was to evaluate a conventional stent, Jostent Flex stent, versus a polytetrafluoroethylene (PTFE)-membrane-covered stent in patients undergoing intervention of a stenosis in an obstructed vein graft.

Hypothesis:

Treatment with the PTFE stent will result in a lower restenosis rate at six-month angiographic follow-up.

Study Design

Study Design:

Patients Enrolled: 211
Mean Follow Up: mean 14 months
Mean Patient Age: mean age 68 years
Female: 11
Mean Ejection Fraction: Mean baseline left ventricular ejection fraction 54% in the conventional stent arm and 55% in the PTFE arm

Patient Populations:

Angina pectoris or documented myocardial ischemia; a hemodynamically significant de novo lesion in an aortocoronary saphenous vein bypass graft with a lesion length of 5-45 mm and a reference diameter of 3.0-5.0 mm by visual estimation, and accessible to percutaneous revascularization

Exclusions:

MI <14 days before intervention, TIMI flow 0 in the target vessel, restenotic lesion, distal ostial lesion (≤5 mm), multiple lesions within the target vessel that cannot all be treated by the same stent type, scheduled for surgery, severe hypertension, and severe liver or renal failure

Primary Endpoints:

Binary restenosis (>50% diameter stenosis) at six months by core lab quantitative coronary angiography

Secondary Endpoints:

Composite of clinical events assessed at one year, defined as occurrence of either death, MI, or TLR (percutaneous transluminal coronary angioplasty at the site of the study stent or coronary artery bypass grafting with new graft to target vessel)

Drug/Procedures Used:

Patients were randomized to either a conventional stent, Jostent Flex stent (n=104), or a PTFE-membrane-covered stent (Jostent Stentgraft; n=102). Neither investigators or patients were blinded to treatment assignment.

Concomitant Medications:

Patients were treated with aspirin (100 mg per day). Heparin and abciximab (bolus and infusion over 12 hours) were recommended for all patients. Ticlopidine (500 mg per day) or clopidogrel (75 mg per day) were started after loading doses at the day of the procedure and continued for three months.

Principal Findings:

Procedural success was similar in the two groups (89% in the conventional stent arm versus 87% in the PTFE stent arm, p=0.63). There was no significant difference in the primary endpoint of binary restenosis rate between the conventional stent arm (20%) and the PTFE stent arm (29%; p=0.15). The late occlusion rate trended higher in the PTFE group (7% vs. 16%, p=0.069) at six-month angiographic follow-up. The composite of death, myocardial infarction (MI), or target lesion revascularization (TLR) did not differ between the treatment arms (31% vs. 31%, p=0.93).

Interpretation:

Among patients with a stenosed vein graft, treatment with the PTFE-membrane-covered stent was not associated with a difference in the primary endpoint of binary restenosis compared with treatment with a conventional stent. The investigators hypothesized that a stent covered with a membrane would seal the lumen and prevent protrusion of proliferating tissue, resulting in reduced microembolization and restenosis.

Similar negative results were reported in the recent RECOVERS trial, which also showed no difference in six-month restenosis or clinical events between the PTFE-covered stent and bare stainless steel stent arms.

References:

Schächinger V, Hamm CW, Munzel T, et al., for the STENTS (STents IN Grafts) Investigators. A randomized trial of polytetrafluoroethylene-membrane-covered stents compared with conventional stents in aortocoronary saphenous vein grafts. J Am Coll Cardiol 2003;42:1360-9.

Clinical Topics: Dyslipidemia, Prevention, Vascular Medicine, Atherosclerotic Disease (CAD/PAD), Nonstatins, Diet, Hypertension

Keywords: Intermittent Claudication, Myocardial Infarction, Stroke, Follow-Up Studies, Ischemic Attack, Transient, Platelet Aggregation Inhibitors, Hyperlipidemias, Ankle Brachial Index, Diarrhea, Peripheral Arterial Disease, Ticlopidine, Risk Factors, Lower Extremity, Clofibrate, Diet, Hypertension


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