Catheterization and Cardiovascular Diagnosis 30:63-68 (1993)
`
`Preliminary Reports ... work in progress
`
`Retrieval Techniques for
`Managing Flexible lntracoronary
`Stent Misplacement
`Karl W. Foster-Smith, MB, BSc, MRCPI,
`Kirk N. Garratt, MD, Stuart T. Higano, MD,
`and David R. Holmes, Jr., MD
`
`With the Increasing use of flexible lntracoronary stents, the like(cid:173)
`lihood of complications, Including stent misplacement, will tend
`to rise. We describe the successful use of three commercially
`available retrieval devices: the nitinol gooseneck snare, the bil(cid:173)
`iary forceps, and the multipurpose basket. We recommend the
`availability of these devices to operators involved in intracoro(cid:173)
`nary stent placement.
`© 1993 wuey·Uss, Inc.
`
`Key words: angioplasty, atherosclerosis, endovascular pros(cid:173)
`thesis
`
`INTRODUCTION
`
`Intracoronary stents are being used with increasing
`frequency not only as bailout devices to treat complica(cid:173)
`tions of percutaneous transluminal coronary angioplasty
`(PTCA) or suboptimal dilatation result, but also for treat(cid:173)
`ment or prevention of restenosis. They require meticu(cid:173)
`lous attention to procedural and periprocedural details
`and medications to minimize complications. Failure of
`stent delivery or stent embolization has been reported,
`particularly for stents that do not have sheath delivery
`systems [ 1-9]. Stent embolization, which usually occurs
`in the systemic circulation, is the result of being unable
`to cross the lesion; when the stent and balloon are being
`withdrawn, the stent can be stripped off the balloon. As
`the frequency of centers implanting stents increases, par(cid:173)
`ticularly during the early learning curve phase, there may
`be increased need for stent removal. During 193 at(cid:173)
`tempted stent placements in the last 4 years, we have
`experienced 4 cases of stent misplacement in 3 patients.
`We describe the retrieval techniques used to remove
`these 4 flexible intracoronary stents.
`
`From the Division of Cardiovascular Diseases and Internal Medicine,
`Mayo Clinic and Mayo Foundation, Rochester, Minnesota.
`
`Received March 8, 1993; revision accepted April 28, 1993.
`
`Address reprint requests to Dr. Kirk N. Garratt, Division of Cardio·
`vascular Diseases, Mayo Clinic, Rochester, MN 55905.
`
`© 1993 Wiley-Liss, Inc.
`
`CASE #1
`
`A 69-year-old man with recurrent angina, postcoro(cid:173)
`nary artery bypass surgery, and restenosis following 3
`recent percutaneous transluminal coronary angioplasty
`(PTCA) procedures was scheduled for Wiktor stent
`(Medtronic, Minneapolis, MN) placement to a proximal
`right coronary artery vein graft lesion. An 8 French right
`coronary bypass Triguide (SciMed Life Systems, Min(cid:173)
`neapolis, MN) was used to engage the vein graft ostium.
`It was crossed with a 0.018" intermediate guidewire and
`a 3.5 mm x 15 mm Wiktor stent and balloon. Consid(cid:173)
`erable difficulty was encountered in attempting to cross
`the lesion, causing the proximal stent loops to be com(cid:173)
`pressed toward the center of the delivery balloon. The
`stent could not be withdrawn into the guide catheter due
`to splaying of the proximal wire loops, so the entire
`system was pulled back into the right iliac artery. The
`guide catheter was removed through the hemostatic
`sheath. A 4 French nitinol gooseneck snare (Microvena
`Corp., Vadnais Heights, MN) with a 15 mm loop diam(cid:173)
`eter and length of 120 em (Fig. lA) was passed through
`the femoral sheath alongside the delivery balloon cathe(cid:173)
`ter and positioned above the guidewire with the snare
`open (Fig. 2a). The guidewire was manipulated through
`the loop (Fig. 2b). The snare was then withdrawn to the
`level of the stent and balloon and tightened. The stent,
`balloon catheter, and snare were all removed as a unit
`through the hemostatic sheath (Fig. 2c).
`The graft stenosis was crossed again with a 0.018 mm
`intermediate wire and a 3.5 mm Mirage balloon (SciMed
`Life Systems). Two inflations were performed to a max(cid:173)
`imum of 12 atmospheres for 2.5 min. A 3.5 mm x 15
`mm Wiktor stent was advanced across the lesion and
`expanded with 6 atmospheres for 90 sec. The proximal
`portion of the stent failed to fully expand despite re(cid:173)
`peated inflations. The Mirage balloon was exchanged for
`a 3.5 mm Force system (USCI-Bard, Billerica, MA).
`One inflation at 19 atmospheres was performed for 2.5
`min. Partial unraveling of the proximal part of the stent
`occurred on withdrawal of the balloon, resulting in an
`elongated portion of wire extending out of the vein graft
`ostium and into the ascending aorta (Fig. 3a). Because
`this configuration posed a risk of thrombus formation
`and embolization, a decision was made to remove the
`stent. The coronary wire and deployment balloon were
`removed. Using a biliary forceps (Medi-Tech, Water(cid:173)
`town, MA) (Fig. lB) (closed diameter 1.6 mm, opened
`diameter 25 mm, length 120 em), the proximal end of the
`
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`64
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`Foster-Smith et al.
`
`Fig. 1. (A) The nitlnol gooseneck snare, (B) biliary forceps, and
`(C) multipurpose basket.
`
`stent was grasped and slowly drawn back into the guide
`catheter (Fig. 3b). The single tantalum filament gradu(cid:173)
`ally uncoiled, and the unwinding stent wire came free of
`the vein graft. Stent release did not result in any angio(cid:173)
`graphic evidence of disruption, excoriation, thrombosis
`or other trauma (Fig. 3c). After stent recovery, the ste(cid:173)
`nosis was estimated as 40%; in view of the refractory
`nature of the lesion to high-pressure dilatation , this re(cid:173)
`sidual stenosis was accepted and no further attempts
`were made to place a stent.
`
`CASE#2
`
`A 65-year-old white female was referred to Mayo
`Clinic with recurrent angina and recurrence of a complex
`left main coronary artery lesion. Her past medical history
`included two coronary artery bypass operations to her
`left coronary artery system and restenosis of a complex
`left main coronary artery lesion , which had 4 months
`previously been treated with directional laser angio(cid:173)
`plasty. The sequential left internal mammary artery graft
`
`(a) After unsuccessful stent placement attempt, equip(cid:173)
`Fig. 2.
`mentIs withdrawn to right iliac artery. Nltlnol gooseneck snare
`Is looped over the distal end of coronary guldewlre. (b) Nltlnol
`gooseneck Is posllloned over stent. (c) Gooseneck snare Is
`tightened over stent and withdrawn through 8F vascular sheath.
`
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`Misplaced Stent Retrieval
`
`65
`
`to the first diagonal and left anterior descending arteries
`was patent. Repeat directional laser angioplasty was rec(cid:173)
`ommended to the patient. The left coronary artery was
`engaged with an 8-F left Judkins catheter (Cordis , Mi(cid:173)
`ami, FL). After 4 passes with a 1.8 mm eccentric exci(cid:173)
`mer laser fiber system (AIS, Irvine , CA), considerable
`improvement was seen, but a significant residual stenosis
`remained. The laser catheter was replaced by a 3.5 mm
`Force balloon which ruptured during the second inflation
`at 20 atmospheres, resulting in a localized dissection of
`the left main coronary artery. Additional balloon angio(cid:173)
`plasty did not resolve the dissection. Consequently, a
`decision was made to attempt placement of a 3.5 mm x
`20 mm Gianturco-Roubin stent (Cook, Bloomington,
`IN). The stent could not cross the stenosis due to calcific
`disease, and during the process the stent became dis(cid:173)
`lodged from its deployment balloon (Fig. 4a) . The cy(cid:173)
`lindrical geometry of the stent was not disrupted and the
`distal end of the guidewire remained in place in the left
`anterior descending artery, so tbe stent was trapped be(cid:173)
`tween the distal end of the guide catheter and the left
`main ostium with the coronary guidewire running
`through its center. The deployment balloon catheter was
`removed. In an attempt to capture the stent, a 3 . 0 mm
`Mirage balloon catheter was passed through the stent and
`inflated to 5 atmospheres. However, the stent could not
`be withdrawn into the guide catheter in its expanded
`form.
`The stent, with its supporting Mirage balloon, and the
`guide catheter were withdrawn down to the iliac artery,
`the guidewire still being in position . On attempting to
`again withdraw the stent into the guide, it was dislodged
`from the baJloon catheter. The balloon catheter was with(cid:173)
`drawn. A multipurpose basket (Medi-Tech) (Fig. IC)
`(closed diameter 1.6 mm , open diameter 20 mm, length
`120 em) was passed through the guide catheter. This
`snared the distal coronary wire preventing stent deploy(cid:173)
`ment into the circulation (Fig . 4b). All were removed as
`a unit through the femoral s heath. The postdilatation left
`main stenosis was measured at 50%. No further attempts
`were made to place a stent.
`
`CASE#3
`
`A 53-year-old white male was transferred to Mayo
`Clinic with a history of unstable angina culminating in
`acute anterior myocardial infarction , which was man(cid:173)
`aged medically. Five days later he suffered recurrent
`anterior myocardial infarction. Emergency coronary an(cid:173)
`giography revealed a 99% occluded proximal left ante(cid:173)
`rior descending coronary artery . Balloon dilatation of
`this lesion was successfully performed , leaving a 30%
`residual stenosis. The patient received high dose heparin,
`
`(a) After placement, the proximal portion of atent Ia
`Fig. 3.
`partially unraveled and extends into aortic root. (b) After cap(cid:173)
`turing the end of the stent wire with a biliary forceps, the atent
`Is removed. The stent uncoils as It Is withdrawn Into the guide
`catheter. (c) No evidence of trauma to proximal vein graft after
`stent removal.
`
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`66
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`Foster-Smith et al.
`
`x 12 mm Gianturco-Roubin intracoronary stent was ad(cid:173)
`vanced through an 8 French Judkins left Bright Tip guide
`catheter (Cordis). The procedure was complicated by in(cid:173)
`advertent placement of the distal coronary wire in the
`first diagonal branch, which resulted in inability to cross
`the lesion with the stent. The stent delivery balloon was
`retracted to permit redirection of the guidewire into the
`distal left anterior descending artery. Upon retraction the
`stent was displaced toward the distal end of its deploy(cid:173)
`ment balloon. The guide catheter, deployment balloon
`and stent were withdrawn (Fig. Sa) to below the level of
`the renal arteries while still maintaining the position of
`the coronary wire in the left coronary artery.
`An attempt was made to retract the deployment bal(cid:173)
`loon and stent into the guide catheter, but this caused the
`stent to come free of the balloon. The position of the
`collapsed stent was stabilized by the coronary guidewire,
`which was still positioned in the diagonal branch . The
`deployment balloon was removed and a biliary forceps
`was advanced (Fig. 5b). The forceps were opened and
`the edge of the stent was grasped without also capturing
`the coronary guidewire. The forceps and stent were re(cid:173)
`moved (Fig. 5c). The guide catheter was repositioned
`and the coronary wire placed in the distal left anterior
`descending. A Gianturco-Roubin 3.5 x 12 mm stent
`was advanced and seated easily across the lesion . After a
`single inflation to 6 atmospheres for 2 min, the stent was
`well deployed. The residual stenosis was estimated at
`20%.
`
`Fig. 4. (a) After unsuccessful attempted stent placement,
`Gianturco-Roubln stent Is stripped from deployment balloon
`but remains aligned with coronary guldewire (arrow). (b) The
`coronary guldewire is grasped (at arrow) with a multipurpose
`basket distal to the stent; the basket Is closed over the
`guidewire by retracting the basket Into a delivery sheath. The
`stent and guidewire are removed by withdrawing the basket.
`
`aspirin, and nitrates during the procedure and was re(cid:173)
`turned to the Coronary Care Unit pain free.
`He developed recurrent chest pain and electrocardio(cid:173)
`graphic abnormalities I hr later and was retur ned to the
`catheterization laboratory. Coronary angiography re(cid:173)
`vealed an occluded proximal left anterior descending ar(cid:173)
`tery at the site of the previous PTCA. A 0 .014" hi-torque
`floppy guidewire was advanced through the occlusion. A
`3.5 mm Stack autoperfusion balloon (ACS, Temecula,
`CA) was positioned across the lesion and inflated to 4
`atmospheres for 15 min. There was marked improvement
`in the appearance of the lesion initially. However, sub(cid:173)
`total reocclusion developed within 10 min. A decis ion to
`proceed with coronary stent placement was made. A 3.5
`
`DISCUSSION
`
`Although stent embolization is not a frequent event, it
`is reported to occur in up to 8% of cases in the current
`literature [ 1- 9]. Fortunately, the majority of cases do not
`result in clinical sequelae. However, the potential for
`permanent or life-threatening complications (such as
`stent embolization to the cerebrovascular circulation) re(cid:173)
`mains.
`The case reports cited here demonstrate the use of
`three different devices to retrieve flexible intravascular
`stents. The first, the nitinol gooseneck snare, has been
`used in the retrieval of a ventriculo-atrial shunt tip,
`guidewires or a Wallstent from the circulation and also in
`the removal of ureteric stents [ 10, 11]. This snare has two
`advantages. First, the loop is at a right angle to the cath(cid:173)
`eter, making intravascular snaring easier than with
`straight devices. Second, the loop is made from nickel(cid:173)
`titanium, increasing its tensile strength and reducing the
`chance of cable fracture.
`The second device described was the biliary forceps.
`This instrument has the advantage of retrieving stents
`without loss of coronary wire position unlike the other
`
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`Misplaced Stent Retrieval
`
`67
`
`two devices where the coronary wire is grasped along
`with the stent and withdrawn .
`The third device used was the multipurpose basket.
`Similar stone baskets have been successful in the re(cid:173)
`trieval of intravascular and intracoronary foreign bodies
`[12- 14]. The spiral device when open fills the vessel
`from wall to wall, simplifying entrapment of the stent.
`The nitinol gooseneck snare has a 4 French (0.052")
`catheter diameter. The other retrieval devices all have a
`diameter of 1.6 mm (0.064"). These devices can easily
`be accommodated by an 8 French guide catheter with an
`internal diameter of 0.080"- 0.084". Once the deploy(cid:173)
`ment balloon is removed, a 7 French guide catheter will
`also acconunodate these devices, although currently all
`stems are delivered through 8 French or larger guide
`catheters.
`When removing a stent with its deployment balloon
`(as in Case # l ), all should be withdrawn to the iliac
`artery. The guide catheter should then be removed and
`the retrieval device introduced through the hemostatic
`sheath alongside the coronary wire. We encountered no
`difficulties withdrawing the captured flexible stents from
`the iliac arteries.
`Pan et al. [ 15) described the use of a handmade re(cid:173)
`trieval set utilizing a 5 or 7 French catheter containing a
`looped coronary wire to retrieve a Palmaz-Schatz stent.
`Muhlestcin et al. [16] commented on the use of a stan(cid:173)
`dard right ventricular bioptome to remove stents already
`deployed in canine coronary arteries (a similar scenario
`to our f~rst case). By grasping its proximal end, the stent
`was retracted and stretched into a straight wire and with(cid:173)
`drawn into the guide catheter. Histological study of the
`canine arteries demonstrated only mild endothelial den(cid:173)
`udation after the procedure. This approach has, at least in
`theory, the risk of stent wire transection related to use of
`a cutting boptome.
`In summary, commercially available retrieval devices
`can be used to retrieve damaged flexible coronary stents.
`Maintaining guidewire position in the coronary tree can
`serve to prevent systemic embolization of a stent that has
`come free of its deployment balloon . The retrieval de(cid:173)
`vices described facilitate practical solutions to a problem
`that is likely to increase in incidence; operators who plan
`to deploy balloon expandable coronary stents should
`have these devices available and be familiar w ith their
`use.
`
`(a) After attempted withdrawal of atent into the tip of the
`Fig. 5.
`guide catheter (thin arrow), the atent Ia compressed and dis(cid:173)
`placed toward the distal and of the deployment balloon (thick
`arrow). The coronary wire is atlll In position. (b) Open biliary
`forc:eps (curved arrows) are edvanced toward the stent (thick
`arrow), which Ia now tree of the deployment balloon In the distal
`abdominal aorta. (c) The closed biliary forceps drawing the cap(cid:173)
`tured atent (arrow) Into the guide catheter.
`
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`wonh H. Sousa JE, Tio F, Almagor Y, Ponder R, Penn IM,
`Leonard B, Levine SL, Fish RD. Palmaz JC: Clinical experience
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`Foster-Smith et al.
`
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`
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