Drug-Eluting and Bare Metal Stenting for Acute Myocardial Infarction in Massachusetts

1
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction in Massachusetts

• Laura Mauri, Treacy S. Silbaugh, Robert E. Wolf,
  Katya Zelevinsky, Ann Lovett, Manu Varma, and
• Sharon-Lise T. Normand
• Brigham and Womens Hospital, Harvard Medical
  School,
• Harvard School of Public Health all in Boston,
  Massachusetts
• March 30, 2008
• American College of Cardiology, Chicago

2
Disclosure Information
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction in Massachusetts
The following relationships exist related to this
presentation
L Mauri Honoraria Abbott, Boston Scientific,
Cordis, Medtronic Modest Level T Silbaugh, R
Wolf, K Zelevinsky, A Lovett, and SL Normand
Salary and research funding from Massachusetts
Department of Public Health M Varma No
disclosures
3
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction

• We wish to thank Paul Dreyer, Ph.D. of the
  Massachusetts Department of Public Health and the
  members of the Mass-DAC PCI Data Adjudication
  Committee

Josh Krasnow, M.D. Anthony Marks, M.D. Theo E.
Meyer, M.D., Ph.D. Kathy Minahan, R.N. Zoran
Nedelijkovic, M.D. Barbara Oxley, R.N. Thomas C.
Piemonte, M.D. Kenneth Rosenfield, M.D. Pinak B.
Shah, M.D. Samuel J. Shubrooks Jr., M.D. James
Waters, M.D. Bonnie Weiner, M.D.
Kurt Barringhaus, M.D. Clifford J. Berger,
M.D. David Cohen, M.D. Angela Corey, R.N. Jean
Crossman, R.N. Daniel Fisher, M.D. Joe Garasic,
M.D. Jean-Pierre Geagea, M.D. Gregory Giugliano,
M.D. Kalon Ho, M.D. Alice Jacobs, M.D. James
Kirshenbaum, M.D.
4
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionBackground

• Acute myocardial infarction represents a large
  proportion of stenting procedures, and is the
  clinical syndrome with the greatest documented
  benefit for PCI
• Yet patients with acute myocardial infarction
  (AMI) have not been included in the major
  randomized trials comparing drug eluting stents
  (DES) to bare metal stents (BMS)
• And specific studies of AMI have been limited in
  size and study duration to detect adverse
  clinical events.

5
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction Objectives

• To evaluate whether the use of DES is associated
  with increased rates of death or MI compared with
  BMS in patients with acute myocardial infarction
• To evaluate whether the use of DES is associated
  with reduction in revascularization compared with
  BMS in patients with acute myocardial infarction

6
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction Methods

• All PCI for NSTEMI or STEMI in Massachusetts
  non-federal hospitals April 2003 Sept. 30,
  2004
• Clinical and procedural factors collected
  prospectively using ACC NCDR instrument and
  reported to Mass-DAC (State Dept of Public Health
  database)
• Mortality from hospital record, MA Registry of
  Vital Records Statistics, Social Security
  website
• Myocardial infarction and revascularization from
  Mass-DAC PCI and CABG data merged with hospital
  discharge data
• Non-Massachusetts residents excluded

7
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction Methods

• Patients assigned to DES or BMS groups based on
  treatment at index procedure
• Patients treated with both types were excluded
• Propensity score matching
• Logistic regression to predict DES treatment by
  up to 63 patient, procedural, hospital variables
• 11 caliper matching of DES to BMS patients
• Primary outcomes Matched risk differences for
  mortality, myocardial infarction and
  revascularization rates at 2 years
• Paired t-test, 2-sided alpha 0.05

8
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction
N21,019 PCI Patients in Massachusetts April 1,
2003- September 30, 2004 Complete 2 year follow-up
12,565 non-MI PCI patients
N8,454 MI Patients (40)
575 non-residents excluded
183 administrative files not linkable
N7,696 Patients
480 patients with both stent types excluded
N4,016 DES Only Patients
N3,200 BMS Only Patients
28 PES
72 SES
9
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionPatient Characteristics
before Match
DES(n 4016) BMS (n 3200) p value
Age yrs 63.6 13.4 64.3 13.9 0.04
Female () 33.0 33.0 0.91
Diabetes Mellitus () 25.6 22.6 0.004
Hyperlipidemia () 66.7 62.2 lt0.001
Hypertension () 69.0 65.1 lt0.001
Current Smoker () 29.0 31.3 0.03
Prior PCI () 14.0 12.8 0.13
Prior MI () 22.3 23.3 0.33
Prior CABG () 8.3 9.8 0.004
10
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionPatient Characteristics
before Match
DES(n 4016) BMS (n 3200) p value
Congestive Heart Failure () 9.4 10.5 0.11
Chronic Lung Disease () 11.1 12.0 0.24
History of Neoplasm () 2.2 3.0 0.02
History of GI Bleeding () 2.4 3.2 0.05
Chronic Renal Insufficiency () 6.1 6.7 0.30
Dialysis () 1.6 1.3 0.21
Clopidogrel Pretreatment () 34.9 32.3 0.02
GPIIb/IIIa Inhibitor Pretreatment () 35.1 38.2 0.007
Although dual antiplatelet therapy (DAP)
compliance data are not available, during the
time period of entry to the study (4/03- 9/04)
consensus recommendations were for 1m DAP for BMS
and 3-6m for DES.
11
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionProcedure Indications
before Match
DES(n 4016) BMS (n 3200) p value
MI type lt0.001
STEMI 38.9 56.8
NSTEMI 61.1 43.2
Procedure status lt0.001
Urgent () 47.5 35.4
Emergency/Salvage () 37.5 54.2
Thrombectomy 7.8 13.8 lt0.001
12
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionProcedural Characteristics
before Match
DES(n 4016) BMS (n 3200) p value
Number of vessels treated 1.18 0.43 1.10 0.32 lt0.001
Number of lesions treated 1.41 0.70 1.31 0.60 lt0.001
Left anterior descending () 43.7 37.0 lt0.001
Circumflex () 32.9 26.0 lt0.001
Right coronary () 39.8 45.8 lt0.001
Left main () 1.5 1.2 0.32
Saphenous vein graft () 3.7 6.1 lt0.001
Arterial graft () 0.1 0.2 0.72
13
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial Infarction
N4,016 patients with DES for MI
N3,200 patients with BMS for MI
Propensity score matched pairs
2629 MI
2629 MI
2,453 (61.1) DES for NSTEMI
1,382 (43.2) BMS for NSTEMI
matched pairs
1,221 NSTEMI
1,221 NSTEMI
1,563 (38.9) DES for STEMI
1,818 (56.8) BMS for STEMI
matched pairs
1,302 STEMI
1,302 STEMI
14
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionPatient Characteristics
after Match
DES(n 2629) BMS (n 2629) SD
Age yrs 64.7 64.2 0.0
Female () 33.7 33.4 0.8
Diabetes Mellitus () 22.4 22.9 -1.3
Hyperlipidemia () 62.1 63.6 -3.2
Hypertension () 66.1 66.7 -1.3
Current Smoker () 31.0 30.8 0.3
Prior PCI () 12.6 12.8 -0.9
Prior MI () 24.0 23.0 2.4
Prior CABG () 9.0 8.8 0.5
SD Percent Standardized Difference Values
lt10 reflect well-matched characteristics
15
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionPatient Characteristics
after Match
DES(n 2629) BMS (n 2629) SD
Congestive Heart Failure (NYHA 3-4) 9.2 8.3 3.1
Chronic Lung Disease () 12.9 12.0 2.9
History of Neoplasm () 2.9 2.7 1.4
History of GI Bleeding () 3.2 3.2 0.2
Chronic Renal Insufficiency () 6.6 6.5 0.3
Dialysis () 1.4 1.5 -1.0
Clopidogrel Preadminstered () 29.6 31.2 -3.5
GPIIb/IIIa Inhibitor Preadminstered () 38.8 37.7 2.4
SD Percent Standardized Difference Values
lt10 reflect well-matched characteristics
16
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionProcedure Indications after
Match
DES(n 2629) BMS (n 2629)
MI type
STEMI 55.4 50.5
NSTEMI 44.6 49.5
Procedure status
Urgent () 37.6 40.2
Emergency/Salvage () 51.8 47.8
Thrombectomy 9.1 8.8
17
Drug-Eluting and Bare Metal Stenting for Acute
Myocardial InfarctionProcedural Characteristics
after Match
DES(n 2629) BMS (n 2629) SD
Multilesion treatment
2 lesions 20.0 21.3 -3.3
3 lesions 3.7 4.7 -4.9
4 lesions 0.7 0.8 -1.8
Target vessel
Left circumflex 26.4 28.2 -3.9
Right coronary 44.8 43.6 2.5
Left main 1.5 1.4 1.0
Saphenous vein graft 5.1 5.0 0.5
Arterial graft 0.2 0.2 0.0
SD Percent Standardized Difference Values
lt10 reflect well-matched characteristics
18
Drug-Eluting Bare Metal Stenting in
Massachusetts Risk Differences in Matched MI
Patient Groups at 2 years
Risk Difference (95 CI), DES v. BMS
Recurrent MI
Death
-2.7 -4.5, 0 P0.002
-1.5 -3.1, 0.2 P0.08
-2.4 -5.0, 0.3 P0.07
-1.9 -4.6, 0.9 P0.18
-3.1 -5.4, -0.8 P0.009
-1.6 -3.7, 0.5 P0.127
19
Drug-Eluting Bare Metal Stenting in
Massachusetts Risk Differences in Matched MI
Patient Groups at 2 years
Risk Difference (95 CI), DES v. BMS
Revascularization
TVR
20
Drug-Eluting Bare Metal Stenting in
Massachusetts 2-Year Outcome in Matched MI
Patients
730
365
180
30
0
No. at Risk
730
365
180
30
0
No. at Risk
2433
2484
2550
2618
2629
DES
2283
2368
2483
2604
2629
DES
2373
2431
2512
2614
2629
BMS
2192
2285
2430
2592
2629
BMS
No. at Risk 0 30 180 365 730
DES 2629 2624 2492 2380 2291
BMS 2629 2618 2443 2250 2148
No. at Risk 0 30 180 365 730
DES 2629 2624 2427 2243 2127
BMS 2629 2618 2372 2091 1957
21
Drug-Eluting and Bare Metal Stenting for MI in
Massachusetts Sensitivity analyses

• Match adjusting for time on market yields
  consistent conclusions
• STEMI group exclusion of programs without surgery
  on site, or patients with gt24h presentation,
  yields consistent conclusions
• No evidence of a 2 day clinical or statistical
  significant benefit which is supportive of no
  residual confounding
• 2 day mortality DES-BMS
• D -0.5 -1.0,0.04
• 2 year mortality DES-BMS
• D -2.7 -4.5, 0

22
Drug-Eluting and Bare Metal Stenting in
Massachusetts Conclusions

• Complete 2 year data are available for 7216
  unique DES or BMS procedures for MI in
  Massachusetts from April 2003- September 2004.
• Propensity matched analysis of 5258 patients with
  MI demonstrated
• No increase in rates of death, or myocardial
  infarction associated with DES as compared to BMS
  use at 2 years overall and for the subsets of
  STEMI and NSTEMI
• Although our aim was to detect a signal of harm,
  we observed lower 2y mortality in STEMI patients
  treated with DES
• A lower rate of repeat revascularization in
  patients treated with DES compared with BMS
  overall and for both subsets.