Longitudinal stent compression predisposing mechanical properties, incidence and predictors

Gregor Leibundgut, MD

Scientific Meeting of the European Bifurcation Club

Barcelona 2012

Medina)0,1,1)Lesion)

CRA)38,)LAO)2

Medina 0,1,1 Lesion

Strategy • Medina type 0,1,1 lesion

• Reverse T-stenting

• Proximal Optimization Technique (POT)

• Crush technique

• Final kissing We considered a 2-stent strategy because the SB is important and heavily diseased.

Main Branch (LAD) Stenting

Side Branch (RD1) Stenting

Text

Side Branch (RD1) Stenting II

After 2nd Stent Placement After Longitudinal Compression

Optical Coherence Tomography (OCT)

Complication Management Complica. on)Management

post)dilata. on

kissing)balloon final)result

2nd)stent)placement

Final Result Final)Result

RAO)cranial LAO)cranial spider)view

Procedure Summary

Scaffold Designs

Stent Alloy Strut thickness (μm) Longitudinal connections Strut orientation

Promus Element PtCr 81 2 diagonal, linear

Taxus Liberté SS 97 3x2 diagonal, curved

Cypher Select SS 140 6 vertical, double-curved

Resolute Integrity CoCr 91 2/3 point, welded

Xience Prime CoCr 81 3 vertical, single-curved

unpublished data

Compressibility by Design

35% 39% 15%

30% 18%

Cypher Element Integrity Taxus Liberté Xience Prime

Leibundgut G, Gick M et al. CCI 2012

Bench Testing Apparatus

Leibundgut G, Gick M et al. CCI 2012

Longitudinal Stability

Strain Hardening Necking

Fracture Point

Ultimate Strength

Strain

Forc

e

Yield Strength

idealized force-strain curve

coronary stent

typical force-strain curve of a solid body

elastic deformation without structural

damage (spring)

Leibundgut G, Gick M et al. CCI 2012

Bench Testing

0 1 2 3 4 5 6

CypherSelect

Strain(mm)

0 1 2 3 4 5 6

TaxusLiberté

Strain(mm)

0

0.3

0.7

1.0

1.3

0 1 2 3 4 5 6

PromusElement

Force(N)

Strain(mm)

0

0.3

0.7

1.0

1.3

0 1 2 3 4 5 6

PromusElement

Force(N)

Strain(mm)

0 1 2 3 4 5 6

XiencePrime

Strain(mm)

0 1 2 3 4 5 6

ResoluteIntegrity

Strain(mm)

unpublished data

Elastic Range

0

0.2

0.4

0.6

0.8

1.0

1.2

PromusElement XiencePrime ResoluteIntegrity TaxusLiberté CypherSelect

0.892

0.1800.1670.3850.049

SpringConstantN/m

m0.015 <0.0001ns ns

(S ffn

e

ss)

Leibundgut G, Gick M et al. CCI 2012

Mechanical Properties

0

0.2

0.4

0.6

0.8

1.0

1.2

PromusElement XiencePrime ResoluteIntegrity TaxusLiberté CypherSelect

0.851

0.3850.5200.668

0.149

UltimateStrength

Force(N)

<0.0001 <0.00010.0002 <0.0001

0.2N

0

0.1

0.3

0.4

0.5

0.7

0.8

PromusElement XiencePrime ResoluteIntegrity TaxusLiberté CypherSelect

0.610

0.3510.2830.401

0.108

YieldForceForce(N)

0.0001 <0.00010.001 0.007

Leibundgut G, Gick M et al. CCI 2012

Frequency

• January 1, 2010 to October 31, 2011

• 2,936 Promus Element stents in 1,295 patients

• Longitudinal stent compression in 20 PCI cases

• 1.44% of PCI cases

• 0.70% of all lesions

• 0.68% of all PES

• Longitudinal stent compression complicates procedure and necessitates additional stent placement

Leibundgut G, Gick M et al. CCI 2012

Predictors | Patient Characteristics

Leibundgut G, Gick M et al. CCI 2012

Predictors | Lesion Characteristics

THANK YOU