Stent Design Impacts Geometric Vessel Distortion Following Coronary Artery Stenting in
Severely Angulated Lesions: Angiographic Analysis of the PLATINUM Trial
Jeffrey J. Popma, MD1, Alexandra Almonacid, MD1, Dean J. Kereiakes, MD2, Ian T. Meredith, AM, MBBS, PhD3, Paul S. Teirstein, MD4, Dominic J. Allocco, MD5, Keith D. Dawkins, MD5, Gregg W. Stone, MD6
1. Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA; The Christ Hospital Heart and Vascular Center/The Lindner Center for Research and Education at The Christ Hospital;, Cincinnati OH 3. MonashHEART, Southern Health, Monash Medical
Centre, Clayton, Victoria, Australia; 4. Scripps Clinic, Division of Cardiovascular Diseases, La Jolla, CA; 5. Boston Scientific Corporation, Marlborough, MA
6. Columbia University Medical Center / New York Presbyterian Hospital and the Cardiovascular Research Foundation, New York, NY
Poster presented at ACC 2013, March 9, 2013.
• The PLATINUM trial randomized 1530 patients with 1 or 2 de novo
native coronary artery lesions (baseline RVD≥2.50 mm to ≤4.25
mm and length ≤24 mm) to receive the CoCr-EES (XIENCE V;
Abbott Vascular) or the PtCr-EES (PROMUS Element; Boston
Scientific).
• Lesions were to be treated with a single planned stent. For XIENCE
V, available stent sizes were 12, 18 and 28 mm; for PROMUS
Element, stent sizes were 12, 20 and 28 mm.
• A post hoc angiographic analysis of the 100 (N=50 CoCr-EES,
N=50 PtCr-EES) most severely angulated lesions (those with the
highest baseline bend) was conducted.
• Vessel angulation (degrees) and curvature (mm-1) immediately
before and after stent implantation were measured by a blinded,
independent angiographic core laboratory using three dimensional
quantitative angiographic software (CAAS V5.10 QCA, Pie
Medical Imaging, The Netherlands).
• Minimum and maximum angulation and curvature were measured
and correspond to end-diastole and end-systole, respectively.
This study was supported by Boston Scientific (BSC).
Disclosures: JJP –Research Grants and Medical Advisory Board for BSC; AA – None; DJK –
Grants/Research Support from BSC, Abbott Vascular and Medtronic, Consultant for BSC,
Abbott Vascular and REVA Medical; ITM –SAB and consultant proctor for BSC; PST –
Consultant Abbott Vascular and BSC; DJA – full-time employee and stockholder of BSC,
KDD - full-time employee and stockholder of BSC, GWS – Consultant BSC
Table. Vessel Straightening Analysis
Factor
All Lesions
Stent Length, mm
Baseline Bend, degrees (at min MLD)
Pre-procedure Angulation, degrees
Post-procedure Angulation, degrees
Change in Angulation, degrees*
Curvature Difference (mm-1)*
Single Stents Only
Stent Length, mm
Baseline Bend, degrees (at min MLD)
Pre-procedure Angulation, degrees
Post-procedure Angulation, degrees
Change in Angulation, degrees*
Curvature Difference (mm-1)*
*Change
CoCr-EES
N= 50
19.4±10.4
79.1±13.5
Min
Max
80.5±22.9
97.0±24.8
55.4±27.1
65.1±30.4
25.2±18.8
31.9±26.4
0.08±0.08
0.06±0.06
N=41
17.2±5.4
78.8±13.6
Min
Max
80.6±23.1
94.6±25.1
56.0±27.5
64.7±29.6
24.7±18.4
30.0±23.5
0.08±0.07
0.06±0.07
PtCr-EES
N=50
22.0±7.5
79.0±11.7
Min
Max
76.0±24.0
91.2±25.9
60.5±28.1
71.5±29.5
15.5±19.2
19.7±21.3
0.06±0.06
0.05±0.05
N=48
21.5±7.1
78.9±11.8
Min
Max
75.4±24.2
90.8±26.3
60.5±28.7
71.7±30.10
14.9±19.2
19.1±21.5
0.06±0.06
0.04±0.05
in angulation and curvature differences were calculated as pre-procedure – post-procedure
P value
0.16
0.97
Min
0.33
0.36
0.01
0.10
Max
0.26
0.28
0.01
0.20
0.002
0.98
Min
Max
0.30
0.49
0.45
0.27
0.02
0.03
0.23
0.29
Maximum
Minimum
Pre-procedure
Post-procedure
Curvature
B Example #2
Pre-procedure
Post-procedure
Angulation
Maximum
Methods
• Baseline demographics and cardiac history were generally similar between patients in the CoCr-ESS and PtCr-EES
arms of this PLATINUM vessel straightening analysis (data not shown).
• Lesion length was significantly longer in the PtCr-EES group compared to CoCr-EES (CoCr 12.4±5.7 vs
PtCr15.2±6.2, P=0.02). The average vessel bend at baseline was 79 degrees in both groups (Table).
• Use of an unplanned stent for bailout or unsuccessful study stent placement was significantly more common with
CoCr-EES vs PtCr (28.0% vs 8.2%, P=0.01), as was treatment with multiple stents (18.0% vs 4.0%, P=0.03).
• The change in angulation (degrees) from pre- to post-procedure was significantly lower in patients treated with
PtCr-EES compared to CoCr-EES (Table).
• The curvature difference from pre- to post-procedure was numerically lower with the PtCr-EES but this did not
reach significance (Table).
• An analysis excluding patients with multiple stents was performed in order to isolate the effect of stent design.
Similar results to the overall analysis were found (Table).
Minimum
Background
Distortion of native vessel geometry after coronary stenting has been
associated with reduced coronary flow velocity and shear stress,
increased stent fracture, impaired vessel healing, and late restenosis.
Greater stent conformability may minimize vessel distortion and
improve early and late coronary flow. This analysis examines the
impact of stent design on vessel straightening in severely angulated
lesions.
Figure 1. Pre- and Post-procedure Examples of Change in Curvature and Angulation
A Example #1
Results
Pre-procedure
Post-procedure
Curvature
Pre-procedure
Post-procedure
Angulation
Both A and B were chosen based on the degree of baseline bend and are from the CoCr-EES arm
Summary and Conclusion
• In highly angulated lesions, unplanned stenting was more frequently
required with CoCr-EES compared to PtCR-EES. Vessel straightening, as
measured by the change in angulation before and after stenting, was
greater with CoCr-EES both overall and when the analysis was restricted
to patients who received a single stent.
• The clinical implications of this finding warrant further study.