Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Longitudinal Stent Deformation
Satyam Rajvanshi
• More contemporary stent benefits
– increased deliverability and conformability
– Improved PCI outcomes
Improved stent deliverability achieved through
– Novel alloys (cobalt chrome or platinum chrome)
– Thinner struts
– Newer ...
• Even with reduction in strut thickness,
innovative designs have enabled maintenance
of radial strength
• However, longit...
• Longitudinal stent deformation (LSD) is
defined as the accidental mechanical
distortion or shortening of a stent in the
...
THE ANGIOGRAPHIC
“WEDDING BAND”!
EuroIntervention 2012;8:267-274
EuroIntervention 2011
LSD
• 0.2% incidence – 0.2% of 4455 PCIs
• 0.09% stents deployed
• 12 published cases : 11 proximal crunch and 1
distal crunch
– 7 Promus Element (Pt-Cr)
– 2 Biomatrix (SS)
– 1 Endeavour ...
• Most common cause
– Unexpected or Excessive penetration of
• Guide catheter
• Guide catheter extension
• Proximal EPD in...
EuroIntervention 2012
• Stents inflated to nominal pressure in a test
fixture
• Stent length 28-30 mm
• Longitudinally compressed by 14 mm
• Lon...
Clinically relevant force – 50 gms
Clinically relevant force – 50 gms
Column
Strength:
Key to less
LSD
• Recommendation
– Additional stent connectors be added to the
Element stent design
– Addressed in Promus Premier
• Major LIMITATION!
– All 6 authors – Abott vascular employees
– Clear conflict of interest!
• Also, clinicians said LSD i...
Circ Cardiovasc Interv February 2014
Point compression on proximal malapposed segment
Partial recoil
But
permanent
deformability
Biomatrix Flex - most resistant to deformation
Element - most easily deformed
SITUATIONAL EXAMPLES
• Withdrawal of a stent delivery system when the balloon gets
caught in struts of the deployed stent
• Crossing of a newly...
ANGIOGRAPHIC OUTCOME
AFFECTED? YES
BUT DOES IT AFFECT MACE?
AVOIDANCE AND TREATMENT
CONCLUSIONS
• Longitudinal stent deformation can occur
secondary to a variety of mechanisms
• Rare but also under-recognised and under...
Before PCI
After PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Longitudinal stent deformation in PCI
Upcoming SlideShare
Loading in …5
×

Longitudinal stent deformation in PCI

1,554 views

Published on

Coronary Stent deformation in PCI

Published in: Health & Medicine
  • Be the first to comment

Longitudinal stent deformation in PCI

  1. 1. Longitudinal Stent Deformation Satyam Rajvanshi
  2. 2. • More contemporary stent benefits – increased deliverability and conformability – Improved PCI outcomes
  3. 3. Improved stent deliverability achieved through – Novel alloys (cobalt chrome or platinum chrome) – Thinner struts – Newer 3D designs – in some stents—reduced number of connectors between adjacent stent rings (crowns) – improves SB access also
  4. 4. • Even with reduction in strut thickness, innovative designs have enabled maintenance of radial strength • However, longitudinal (or axial) strength may be lower with these new designs and is not routinely reported by stent manufacturers
  5. 5. • Longitudinal stent deformation (LSD) is defined as the accidental mechanical distortion or shortening of a stent in the longitudinal axis following stent deployment
  6. 6. THE ANGIOGRAPHIC “WEDDING BAND”!
  7. 7. EuroIntervention 2012;8:267-274
  8. 8. EuroIntervention 2011
  9. 9. LSD • 0.2% incidence – 0.2% of 4455 PCIs • 0.09% stents deployed
  10. 10. • 12 published cases : 11 proximal crunch and 1 distal crunch – 7 Promus Element (Pt-Cr) – 2 Biomatrix (SS) – 1 Endeavour (Co-Cr) – 1 Taxus liberte (SS) – 1 Resolute Integrity (Co-Cr) • Average length of stents implanted – 30.7 mm
  11. 11. • Most common cause – Unexpected or Excessive penetration of • Guide catheter • Guide catheter extension • Proximal EPD in SVG-PCI – Mechanical conflict between proximal malapposed stent struts and Post-dialatation balloon
  12. 12. EuroIntervention 2012
  13. 13. • Stents inflated to nominal pressure in a test fixture • Stent length 28-30 mm • Longitudinally compressed by 14 mm • Longitudinal compression force - measured as a function of the compression distance • Plot of the longitudinal compression force versus amount of longitudinal compression was generated
  14. 14. Clinically relevant force – 50 gms
  15. 15. Clinically relevant force – 50 gms
  16. 16. Column Strength: Key to less LSD
  17. 17. • Recommendation – Additional stent connectors be added to the Element stent design – Addressed in Promus Premier
  18. 18. • Major LIMITATION! – All 6 authors – Abott vascular employees – Clear conflict of interest! • Also, clinicians said LSD is as common is all platforms – but more recognised in ELEMENT – the flipside of better visibility!
  19. 19. Circ Cardiovasc Interv February 2014
  20. 20. Point compression on proximal malapposed segment Partial recoil But permanent deformability
  21. 21. Biomatrix Flex - most resistant to deformation Element - most easily deformed
  22. 22. SITUATIONAL EXAMPLES
  23. 23. • Withdrawal of a stent delivery system when the balloon gets caught in struts of the deployed stent • Crossing of a newly deployed stent with a stent delivery system for treatment of a distal lesion • Crossing of a balloon dilatation catheter through a deployed stent for post-dilation of the stent • Guide catheter contact with the stent after stent deployment due to ostial location or deep-seating of the guide • IVUS pull-back during post-deployment inspection of the deployed stent Malapposition of struts – MC underlying pathophysiology
  24. 24. ANGIOGRAPHIC OUTCOME AFFECTED? YES BUT DOES IT AFFECT MACE?
  25. 25. AVOIDANCE AND TREATMENT
  26. 26. CONCLUSIONS
  27. 27. • Longitudinal stent deformation can occur secondary to a variety of mechanisms • Rare but also under-recognised and under- reported • More common in complex angiographic disease • Identification is important as, left untreated, it may be associated with MACE • Although seen with several different stents, in the published series - more commonly observed with the Promus Element stent. Engineering studies also give scientific logic behind this.
  28. 28. Before PCI
  29. 29. After PCI

×