M Webster

1
Vascular Protection in High-Risk Non-ST Elevation
Acute Coronary Syndromes Angioplasty
Balloon-associated Coronary Debris and the EZ
FilterWire

• M Webster
• Auckland City Hospital
• Auckland, NZ
• on behalf of R Whitbourn, D McClean, C Juergens,
  H Lowe, G Barbeaux, P Matsis, D Walters, G
  Devlin, W Hui, D Brieger, G Tullyxx and the A-F
  Investigators
• x speakers honoraria, xx BSC employee

2
Study Centres
Canada 3
Sponsor Boston Scientific, Mountain View, CA,
USA
Data Coordinating Centre ECG Core
Laboratory HCRI, Boston, USA
Australia 7
Angiographic Core Laboratory CRF, New York, USA
New Zealand 4
Pathology Core Laboratory Concord Hospital
Sydney, Australia
3
Enrolling Centers

• Center PI Patients
• St Vincents, Melbourne R. Whitbourn 32
• Auckland City, Auckland M. Webster 29
• Christchurch, Christchurch D. McClean 21
• Liverpool, Sydney C. Juergens 20
• Laval, Quebec G. Barbeau 9
• Wellington, Wellington P. Matsis 8
• Prince Charles, Brisbane D. Walters 8
• Waikato, Hamilton G. Devlin 6
• Royal Alexandra, Edmonton W. Hui 6
• Concord, Sydney D. Brieger 4
• Box Hill, Melbourne G. New 3
• Prince of Wales, Sydney N. Jepson 2
• CHUM, Montreal F. Reeves 2
• John Hunter, Newcastle S. Thambar 1

4
(No Transcript)
5
Study Design

• Prospective, multicenter, unblinded, two-arm,
  randomized trial
• Selected high-risk patients with nonSTEMI acute
  coronary syndromes
• PCI using the BSC FilterWire EZ vs standard PCI
  without FilterWire EZ
• 150 patient pilot for pivotal protocol
• Provision for two additional cohorts
• - up to 450 patients

6
FilterWire EZ 3.5-5.5mm 2.25-3.5mm
7
Study Population

• Non ST elevation ACS with "high risk" clinical
  features during 24 hours prior to angiography
• elevated troponin
• angina at rest
• dynamic ST or T wave changes (not ST elevation
  MI)
• Culprit lesion with "high risk" angiographic
  features (2 or more of the following)
• intra-coronary filling deficit consistent with
  thrombus
• lesion ulceration
• eccentric shape
• irregular or scalloped border
• abrupt edges to the lesion
• lesion length gt20 mm

8
(No Transcript)
9
Primary Endpoint

• In-hospital MACE
• - death, recurrent myocardial infarction
  (CK-MBgt3x normal), emergency CABG, repeat target
  vessel revascularisation

10
Secondary Endpoints

• MACE at 30 days
• Change in CK-MB 6-24hours post-PCI
• Change in troponin T 6-24 hours post-PCI
• Device success FilterWire EZ
• Incidence of embolic recovery
• TIMI flow post-PCI

11
Baseline Characteristics

• FilterWire EZ Control
• Patients, n 77 74
• Age, mean (sd) 58(11) 60(13)
• Male, 83 89
• European, 88 88
• Previous angina, 40 42
• Diabetes, 16 26
• Smoker never, 29 34
• Hypertension, 39 46
• Dyslipidemia, 69 62

12
Baseline Angiographic Findings

• FilterWire EZ
  Control
• Reference vessel, mm 3.1(0.6) 3.1(0.6)
• Diameter stenosis, 78(14) 76(12)
• Lesion location - RCA,LAD,LCX , 37,39,24 44,32,25
  
• Lesion length, mm 15.8(7.6) 16.8(10.2)
• Lesion ulceration, 5.6 11.2
• Lesion calcification - mod/severe, 29 34
• TIMI III flow, 60 67

13
Primary Endpoint

• p0.793

14
Secondary Endpoints

• FilterWire EZ
  Control
• MACE 30 day, 12 11
• Change CK-MB 5.1(20) 4.1(6)
• Change troponin T 0.4(0.7) 0.4(0.6)
• Device success, 97 n/a
• Embolic recovery, 42 n/a
• Post-PCI TIMI III, 94 94

15
Subset Analyses

• No difference between FilterWire EZ and control
  groups in
• Patient treated with planned glycoprotein
  IIb/IIIa inhibitors
• Diabetic patients
• Patients pre-treated with clopidogrel
• Patients with prior thrombolytic therapy

16
Why Was There No Benefit With FilterWire?

• Wrong patho-physiology?
• embolism occurs during PCI for nonSTEMI
• - histology, thrombectomy, MRI
• Wrong lesions selected?
• only 42 had emboli captured
• calcified vs thrombotic lesions
• Incomplete protection?
• embolism with positioning the device
• filter mouth/ vessel wall apposition
• incomplete side branch protection
• small particle embolism
• Insufficient study population?
• - type II error

17
(No Transcript)
18
(No Transcript)
19
Summary

• A-F is the only randomised trial of a vascular
  protection device undertaken in non-STEMI acute
  coronary syndrome patients
• No difference between FilterWire EZ and control
  groups in in-hospital MACE or post-procedure
  CK-MB or troponin elevation
• Routine use of vascular protection devices in
  such patients does not appear warranted
• - further angiographic analysis may reveal
  sub-groups at particular risk for embolism