Distal filter protection during saphenous vein graft stenting
Technical and clinical correlates of efficacy
Gregg W. Stone, MD, FACC*,*,1,
Campbell Rogers, MD, FACC ,1,
Steve Ramee, MD, FACC ,
Christopher White, MD, FACC,
Richard E. Kuntz, MD, FACC,
Jeffrey J. Popma, MD, FACC,
John George, MD, FACC ,
Steve Almany, MD, FACC|| and
Steve Bailey, MD, FACC¶
* The Cardiovascular Research Foundation and Lenox Hill Hospital, New York, New York, USA
Brigham & Women’s Hospital, Boston, Massachusetts, USA
Ochsner Clinic, New Orleans, Louisiana, USA
Western Pennsylvania Hospital, Pittsburgh, Pennsylvania, USA
|| William Beaumont Hospital, Royal Oak, Michigan, USA
¶ University of Texas San Antonio, San Antonio, Texas, USA
View larger version (114K):
[in a new window]
|
Figure 1 The FilterWire EX, consisting of a 0.014-inch steerable guidewire on which a freely rotating distal polyurethane filter is mounted, shown in its deployed configuration (top and middle) and retracted position (bottom) after being withdrawn into the delivery/retrieval sheath (white arrow). A distal nosecone (black arrow) prevents passage of the sheath beyond the wire tip
|
|
View larger version (23K):
[in a new window]
|
Figure 2 Diagrammatic representation of the FilterWire across a vein graft lesion, with the minimal distances pre-specified in the phase II protocol for optimal performance.
|
|
View larger version (78K):
[in a new window]
|
Figure 3 Potential failure mode—lack of filter apposition against the vessel wall. (A) Post-stenting of the mid shaft of the saphenous vein graft to the right coronary artery (black arrow) with the FilterWire in place (white arrow). (B) Magnification of panel A—the nitinol loop of the FilterWire may be seen. (C) Further magnification and enhancement of the FilterWire, showing that the nitinol loop (black arrow) and collection filter (cross hatched net) are clearly lifted off the inferior wall of the vein graft, likely due to geometric wire bias resulting from placement of the distal wire tip in the posterolateral branch (white arrow). Relocating the guidewire tip into the more inferior posterior descending artery may have apposed the filter loop against the vein graft wall.
|
|
View larger version (103K):
[in a new window]
|
Figure 4 Potential failure mode—excessively distal lesion resulting in incomplete filter opening or unprotected native side branches. (A) Ulcerated lesion (arrow) in the distal shaft of the saphenous vein graft to the obtuse marginal branch of the left circumflex artery. (B) FilterWire deployed, with the distal nitinol loop protruding into the upper branch of the bifurcating obtuse marginal (arrow). (C) As a result, the polyurethane collection filter (arrow and cross hatched net) cannot open fully and is compressed in the undersized branch (<3.0 cm), impairing particulate recovery both in the partially protected superior branch and unprotected inferior branch.
|
|
View larger version (17K):
[in a new window]
|
Figure 5 Cumulative 30-day major adverse cardiac event (MACE) rates in 48 patients in the phase I study compared to 230 patients in the phase II study. MI = myocardial infarction; TLR = target lesion revascularization.
|
|
|
