03:15 pm – 03:30 pm Lecture: Bioresorbable vascular scaffolding (BVS) in clinical practice: what...

03:15 pm – 03:30 pmLecture: Bioresorbable vascular scaffolding (BVS) in clinical practice: what can we expect after CE Mark?

Raul MorenoUniversity Hospital La Paz

Madrid, Spain

JACC 1999;34;1498-1506.

START randomized study (n=452)Long-term follow-up

8-June-2011

The benefit of BMS is within the first months.

Is there any advantage of a permanent scaffolding?And any disadvantage?

Mechanical support is needed to avoid negative

remodeling and vessel shrinkage, that occur during the first 6 mo.

Bioresorbable vascular scaffolding (BVS)

Two Patients with Extremely Late (8 and 12 Years) Bare-Metal Stent Thrombosis: The Risk Never Completely Disappears!

8-June-2011

J Invasive Cardiol 2008;20:E329-330.

Long-term safety problems of coronary stents


Am J Med 2006;119:1056-1061.

The problem of VLST is more evident with DES

8-June-2011

J Am Coll Cardiol 2008;52:1134-1140.


Is there a need for bioabsorbable stents?

Potential advantages of bioasborbable stents• Risk of stent thrombosis never completely dissapears.

• Need for indefinite anti-platelet therapy.• Potential limitation for future CABG.• Stent fracture.• Prevent late stent malapposition & allow positive remodeling.

Stent in thrombus containing lesions.• Side branch compromise in bifurcations.• Bifurcations: Long-term safety issues of 2-stent techniques.• Aorto-ostial lesions.• Concerns about endothelial function.• PCI in children.• IRM & MSC imaging.

8-June-2011Bioresorbable vascular scaffolding (BVS)

0

0,2

0,4

0,6

0,8

1

1,2

1 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8 1,9 2

BA

BMS

SESEES

PES

MgAG 1.42; LL 1.08 mm PROGRESS-AMSLate loss (4 months):• 42% vessel shrinkage• 45% hyperplasiaToo quick absortion

Lancet 2007;369:1869 PCR 2011

8-June-2011

Previous bioabsorbable stents

DREAMS

AG 1.44; LL 0.68 mm BIOSOLVE-1

Acute gain(mm)

Late loss(mm)

REVAAG 1.81; LL .1.89 mm

LL: NIH & loss of stent area

TCT 2009 & TCT 2010


Net gain = 1

Lactic Acid(C3H6O3)

L-LA

D-LA

Meso L,D-LA

Racemic D,L-LA

CO2

&H2O

Krebs

Cycle

Poly-lactic acid- Poly-L-LA (PLLA).- Poly-D,L-LA (PDLLA).- etc.

~LA~LA~LA~LA~LA~LA~

J Exp Biol 2005;208:4561

8-June-2011

Polylactic acid


*Polymer: a large molecule (macromolecule) composed of

repeating structural units.

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1 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8 1,9 2

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BMS

SESEES

PES

Mg

Tamai(PLLA)

AG 1.57; LL .75 mmLL: neo-intimal hyperplasia

Circulation 2000;102:399 TCT 2009 & TCT 2010

8-June-2011

REVA

DREAMS

Acute gain(mm)

Late loss(mm)


Net gain = 1

• Acute gain should be optimal (radial strength).• Absorption should not be too quick.• Neo-intimal hyperplasia occurs: release anti-proliferative drugs.

Lessons:

BVS (Abbott vascular)

• Polymer backbone (PLLA) Semicrystalline• Polymer (PDLLA) and everolimus matrix. Amorphous


ABSORB (Cohort A)

Eurointervention 2005;1:58-65 Lancet 2008;371:899-907

0.300.501.98NIH area (mm2)

-16.6-7.2-29.4Ʌ Lumen area (%)

-11.2-0.3-2.0Ʌ Stent area (%)

0.440.100.87Late loss (mm)

BVSEESBMS

*EES and BMS provided by SPIRIT-I

6 mo. IVUS: reasons for late loss

8-June-2011

Shrinkage (“late recoil”)… that does not continue

from 6 mo. to 2 yr (!!)

NCT00300131


(30 patients treated with 3x12 or 3x18 mm BVS)

• Clinical FU (4 yr): 1 NQMI, 2 non-cardiac deaths, no ST.• OCT: resorption begins at 6 mo, almost complete at 2 yr.

• Same composition, dose of everolimus & resorption time.• Same strut thickness (150 µm).• Modified platform designed with a reduced maximal circular unsupported scaffold area (MCUSA) and a different manufacturing process of the polymer.• More uniform strut distribution.• Similar profile to a 1st-generation DES:

8-June-2011

Second generation BVS

BVS 1.1 Cypher Select

Profile 1.40 1.23

Strut thickness (µm) 158 (150 + 6-8 polymer) 164 (140 + 24 polymer)


0.300.501.98NIH area (mm2)

-16.6-7.2-29.4Ʌ Lumen area (%)

-11.2-0.3-2.0Ʌ Stent area (%)

0.440.100.87Late loss (mm)

BVSEESBMS

*EES and BMS provided by SPIRIT-I0.08

-5.4

-2.0

0.19

BVS 1.1


ABSORB (Cohort B)n = 101 (3x18 mm stents)

Current data: up to 1 year no deaths, no QMI, no stent thrombosis

TCT 2010 NCT00856856 PCR 2011

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1

1,2

1 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8 1,9 2

BA

BMS

SESEES

PES

Mg

Tamai(PLLA)

BVS-1AG 1.24; LL .44 mm

Lancet 2008;371:899

BVS-2AG 1.26; LL .19 mm

TCT 2010

8-June-2011

REVA

DREAMS

Acute gain(mm)

Late loss(mm)


Net gain = 1

Raul Moreno

Reflection:In-stent late loss is a valid measurement to evaluate the efficacy of DES vs BMS and in head-to-head trials, but…May be that late loss is not valid to compare BVS and DES, because of different mehanical properties…May be that NET GAIN is the best parameter.

ONGOING & FUTURE TRIALS:

■ ABSORB Extend: ~ 1,000 patients, 100 centers. Single arm.No angio. follow-up (clinical end-points).

■ ABSORB Randomized study: ~ 500 patients. RCT vs Xience.Angio follow-up.


months

Preliminary data

No episodes of stent thrombosis

What when I

had BVS in my cath.

Lab?

8-June-2011

• STRENGTH: No permanent device.

• WEAKNESS: Mechanical concerns.

• Consider in patients with soft plaques in whom VLST may be more frequent...• What about complex lesions? I need studies.

Abbott Receives CE Mark Approval for World's First Drug Eluting Bioresorbable Vascular Scaffold for

Treatment of Coronary Artery Disease


• Fully bioabsorbable stents (BVS) are already here !

• Absorption and vessel wall integration are real phenomena.

• We do not have to worry about acute recoil.

• Neo-intimal hyperplasia inhibited by everolimus.

• Vessel shrinkage (late recoil) solutioned with BVS 1.1.

• No early, late or very late ST observed in ABSORB A&B (n=131) or the interim data of ABSORB-EXTEND.

• Concerns about acute gain (immediate result) in some subsets. Thus, lesions not included in ABSORB may be considered “off-label” (studies with complex lesions needed).

8-June-2011

CONCLUSIONS


03:15 pm – 03:30 pm Lecture: Bioresorbable vascular scaffolding (BVS) in clinical practice: what...

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Transcript of 03:15 pm – 03:30 pm Lecture: Bioresorbable vascular scaffolding (BVS) in clinical practice: what...