Assessment of the Medtronic AVE Interceptor Saphenous Vein Graft Filter System - AMEthyst

Description:

The goal of the trial was to evaluate use of a novel distal protection device among patients undergoing percutaneous coronary intervention (PCI) of a saphenous vein graft (SVG).

Hypothesis:

The Interceptor PLUS embolic protection device will be noninferior to commercially available devices.

Study Design

  • Randomized
  • Stratified

Patients Enrolled: 797
NYHA Class: None – 9%, I – 10%, II – 30%, III – 24%, IV – 27%
Mean Follow Up: 30 days
Mean Patient Age: 69 years
Female: 21

Patient Populations:

• Multivessel PCI in an unlimited number of target lesions in up to two SVGs
• Subjective or objective evidence of ischemia
• Target lesion in an SVG, 50 and <100% stenosed
• Vessel diameter 2.5-5.25 mm
• Target vessel with TIMI 1 flow or greater

Exclusions:

• Recent MI <24 hours, with positive creatine kinase-myocardial band or acute MI
• Surgery within 30 days
• LVEF <25%
• Target lesion previously stented
• Target lesion within 5 mm of graft ostium

Primary Endpoints:

MACE (death, MI, or repeat revascularization) at 30 days, evaluated for noninferiority

Secondary Endpoints:

• Individual components of the composite outcome
• Elevated creatine kinase-myocardial band during index hospitalization
• In-hospital MACE
• Device success defined as successful deployment and retrieval of embolic protection device
• Clinical success defined as device success with no in-hospital MACE

Drug/Procedures Used:

Patients were randomized 2:1 to use of the Interceptor PLUS distal protection device (n = 533) or control distal protection group (n = 264). The control arm used distal protection with either the GuardWire (n = 191) or FilterWire EZ (n = 73) at the choice of the physician.

Concomitant Medications:

Patients received 325 mg of aspirin and either 300 mg of clopidogrel or 500 mg of ticlopidine. Aspirin was continued indefinitely and clopidogrel or ticlopidine for 1 month (bare-metal stent) or 3-6 months (drug-eluting stent). The operator could use a glycoprotein (GP) IIb/IIIa inhibitor; however, the intent to do so was recorded prior to randomization. Patients were then stratified according to intent of GP IIb/IIIa inhibitor use.

Principal Findings:

At study entry, 61% of patients had unstable angina and 10% had prior PCI to the target lesion. Mean left ventricular ejection fraction (LVEF) was 51%. The mean age of the SVG was 11 years. GP IIb/IIIa inhibitors were used in 40% of cases. An average of 1.28 stents per patient were used in the Interceptor group, and 1.39 stents in the control group.

Preprocedure minimal lumen diameter (MLD) was 1.14 mm and postprocedure was 3.51 mm in the Interceptor group. Preprocedure MLD was 1.14 mm and postprocedure was 3.40 mm in the control group (p = 0.02). Final Thrombolysis In Myocardial Infarction (TIMI) flow grade was similar between groups (TIMI flow grade 3, 98.1% vs. 97.4%). Device success did not differ for the Interceptor group compared with the control group (90.5% vs. 93.8%, p = 0.13).

The primary endpoint of major adverse cardiac events (MACE) at 30 days met the criteria for noninferiority between the Interceptor group and the control group (8.0% vs. 7.3%, p = 0.025 for noninferiority; p = 0.77 for superiority). The majority of the MACE rate was made up of MI events (8.0% in the Interceptor group and 6.1% in the control group, p = 0.38), with only two deaths in the control group and one target lesion revascularization in each group. Stent thrombosis occurred in 0.4% of the Interceptor group and 0.8% of the control group (p = 0.60).

Interpretation:

Among patients undergoing PCI of an SVG, use of the novel Interceptor PLUS distal protection device was shown to be noninferior to the control distal protection group for the endpoint of MACE at 30 days. This new device was deployed successfully in >90% of patients without apparent safety concerns such as vessel perforation, bleeding, or stroke.

While distal embolization protection devices have not shown success in native coronary lesion PCI, use of such devices has shown benefit in PCI of SVG lesions, as demonstrated in the SAFER trial. The novel Interceptor PLUS distal protection device, although not superior to current distal protection devices, may provide an additional choice for a distal protection device. An advantage of this device may be the wide range of indicated reference vessel diameters (2.5-5.25 mm). The smallest indicated vessel size for the FilterWire is 3.5 mm.

The observed MACE rate was lower than anticipated, which resulted in expansion of the original sample size from 600 to close to 800 patients. During the initial study period, an earlier version of the Interceptor device was used in 54 patients.

Last, the control group consisted of the combined outcomes of the GuardWire and the FilterWire groups, which were selected according to operator preference. The GuardWire is technically different from the FilterWire because the former uses an occlusive balloon, whereas the latter uses a filter.

References:

Kereiakes DJ, Turco MA, Breall J, et al. A novel filter-based distal embolic protection device for percutaneous intervention of saphenous vein graft lesions: results of the AMEthyst randomized controlled trial. J Am Coll Cardiol Intv 2008;1:248-57.

Presented by Dr. Dean J. Kereiakes, at TCT 2007, Washington, DC.

Clinical Topics: Heart Failure and Cardiomyopathies, Invasive Cardiovascular Angiography and Intervention, Atherosclerotic Disease (CAD/PAD), Heart Failure and Cardiac Biomarkers, Interventions and Coronary Artery Disease

Keywords: Coronary Artery Disease, Myocardial Infarction, Stroke, Embolic Protection Devices, Thrombosis, Saphenous Vein, Macrolides, Stroke Volume, Platelet Membrane Glycoprotein IIb, Stents, Percutaneous Coronary Intervention


< Back to Listings