“SHEPHERD” TECHNIQUE FOR STENT DEPLOYMENT

JASON WENDEROTH

PRINCE OF WALES AND LIVERPOOL HOSPITALS

SYDNEY

JWENDEROTH@SNIS.COM.AU

TWO MAJOR CHALLENGES IN STENT DEPLOYMENT

• Stent torsion

• Stent prolapse into aneurysm

THE TORSION PROBLEM

• Tortuous anatomy

• ”Round-the-world” access

• Long stents

THE TORSION PROBLEM

• Torque on catheters transmitted to FDS

• Mid/proximal stent twists

• Non-opening

• Angioplasty-resistant

THE PROLAPSE PROBLEM

• Broad-necked/giant aneurysms

• Aneurysms occupying >50% circumference of vessel

• Insufficient proximal, distal or lateral support during “push” phase of stent deployment

FDS TORSION PROBLEM

• Alternate unsheathing of stent delivery catheter and stent

• Intermediate catheter (+/- buddy wire) provides support for delivery catheter and stent

• Intermediate catheter can be used to “nudge” proximal end of stent for optimal opening

65M ex-smoker

FIRST PROCEDURE

• Aneurysm crossed “round the world”, microcatheter in M2

• Intermediate catheter proximal to aneurysm

• Failed FDS deployment:

• PED 4.75 x 30mm

• PED 4.5 x 30mm

• FRED 4.5 x 26mm

• Acute stroke presented – procedure abandoned; rebooked

THE ”SHEPHERD” TECHNIQUE

• Initial access beyond aneurysm via microcatheter

• Direct or “round the world”

• Standard or balloon microcatheter

• Torque accrues on primary access catheter

• Intermediate catheter advanced distally over primary catheter

• Stent delivery catheter (no torque) via intermediate catheter +/- buddy wire alongside if concerned re stent prolapse

Intermediate catheter

• Distal balloon access

• Inflate balloon for stability

• Torque stored in loop

• Tension on balloon catheter to remove loop

• Torque transmitted to balloon shaft

• Balloon shaft straight, tension stored

• Use balloon shaft as rail

• Advance intermediate catheter over balloon shaft

• Place intermediate catheter well distal to aneurysm

• Can tension balloon shaft to cross aneurysm “lip”

• Final position of intermediate catheter

• Deflate balloon and remove

• May leave “buddy” wire in position if very difficult/tortuous access

Buddy wire

• Remove balloon

• Prepare stent-delivery catheter

• Advance stent delivery catheter as distally as is safe

• Maintain intermediate catheter position +/-buddy wire

• Commence unsheathing of stent lead wire

• Maintain intermediate catheter position

• Withdraw intermediate catheter

• Expose stent delivery catheter in preparation for stent delivery

• Gradual retraction of delivery catheter until stent opens distally and apposes wall

• Slow unsheathing of delivery catheter to permit unsheathing of next stent segment

• Buddy wire can be very helpful here…

• Next segment of stent delivered

• Manipulation by freely-moving delivery catheter with intermediate catheter support

• Gradual retraction of delivery catheter and intermediate catheter until stent opens distally and apposes wall

• Next segment of stent delivered

• Manipulation by freely-moving delivery catheter with intermediate catheter support

65M ex-smoker

65M ex-smoker

65M ex-smoker

SUMMARY

• You’re probably doing this already

• If not, try it – it works!

• We find it useful with difficult anatomy to get our stents open