Acute Myocardial Infarction: Results of the DHMC Regional Registry Nathaniel W. Niles, MD December 6

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Acute Myocardial Infarction Results of the DHMC
Regional Registry Nathaniel W. Niles, MD
December 6, 2004Dartmouth-Hitchcock Medical
Center
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December 2001
Acute ST elevation MI is now on the DHMC ALWAYS
TAKE list
For Age75 increased risk of ICH, consider
Primary PCI if Call-to-table time Primary thrombolytic therapy with TNK plus
enoxaparin
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DHMC STEMI Registry

• Goals
• Assess safety and effectiveness of specific novel
  management strategies (facilitated PCI for
  transfer patients)
• Monitor regional outcomes over time in order to
  assess the impact of overall quality improvement
  efforts

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STEMI Registry

• Case Report Form
• Emergency Room
• Presentation (Hx/PE), ECGs, Treatment, Timing of
  Treatment
• Cath Lab
• TIMI Flow,Timing of reperfusion, Intervention,
  Extent of CAD
• Follow-up
• Death, Stroke, Recurrent MI, CHF, Bleeding
  Complications, Repeat Revascularization
  Procedures
• Enrollment
• Initiated 12/01
• Cath lab database query
• 1/01-12/01 retrospective chart review
• 1/02-3/04 prospective chart review
• 4/04-7/04 prospective cath lab data entry

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Safety and Effectiveness of specific novel
management strategies Facilitated PCI in
Moderate to High Risk Patients Requiring Hospital
Transfer for PCIPresented at TCT 2004
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Clinical history consistent with acute myocardial
infarction and ST elevation, LBBB or anterior ST
depression consistent with acute posterior
MI N564
Presenting to DHMC or Local Hospital N 125 (22)
Presenting to Remote Hospital N 439 (78)
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Door-to-Balloon Time
Time in minutes

• Reperfusion was delayed on average more than 70
  minutes among facilitated PCI strategy patients

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Pre-Cath Lab Outcomes

• Facilitated PCI strategy patients arrived at
  the cath lab in more stable condition

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Cath Lab Findings and Outcomes
Initial TIMI Flow in IRA
Cath Lab Intubation or IABP
of Patients
of Patients

• Facilitated Strategy yielded more patent
  arteries and was associated with less complcated
  procedures

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In-hospital Outcomes
p0.025
ns
p0.098
ns
of Patients
ns
ns
ns
ns
ns
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Conclusions
Transfer for facilitated PCI
Optimal 1 PCI
vs.

• Longer delays before reperfusion (avg. 70
  minutes)
• But
• No greater likelihood of deterioration pre-cath
• Less likely to have ischemia in lab and had less
  complicated procedures
• Better initial infarct artery flow and overall
  better clinical outcomes
• Tended to have more bleeding problems
• But
• no increase in ICH

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Monitoring Regional Outcomes Over Time
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DHMC STEMI Transfer Volumes Q1(01)-Q2(04)
Number of STEMI Patients
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AMI Transfer Patients 01? 04 In-hospital
Mortality
Mortality
Year
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AMI Transfer Patients 01? 04In-hospital MACE
MACE
Year
Death, Recurrent MI, ICH, Repeat
revascularization
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AMI Transfer Patients In-hospital Bleeding
Complications

Year
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Possible Explanations for Improving Outcomes

• Lower risk patients now transferred
• Reduction in delays to reperfusion
• Volume effect Improved outcomes with increased
  volume
• Effect of half dose lytic protocol

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DHMC STEMI Mean TIMI Risk Score Q1(01)-Q2(04)
TIMI Risk Score
Composite of advanced age, CV risk factors,
hypotension, tachycardia, high Killip class, low
body weight, anterior MI location, delay in Tx
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DHMC STEMI Mean Door-to-Balloon time
Q1(01)-Q2(04)
Door-to-Balloon time (min)
Quarter
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DHMC STEMI Transfer Volumes Q1(01)-Q2(04)
Number of STEMI Patients
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AMI Transfer Patients By Intended
DoseIn-hospital Mortality
ppns
p Mortality
Lytic Dose Strategy
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AMI Transfer Patients By Intended DoseTIMI Risk
Score
p0.007
pns
pAverage TIMI Risk Score
Lytic Dose Strategy
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AMI Transfer Patients By Intended
DoseReperfusion and Facilitated Course
No lytic given
Half dose lytic
Full dose lytic
TIMI 3 Flow on Initial Angio
Persistant CP or ST elevation
Cath Lab IABP or Intubation
Clinical Deterioration Pre-Cath
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AMI Transfer Patients By Intended
DoseDoor-to-Balloon Time
p0.0001
p0.0023
p0.0164
Door-to-Balloon Time (min)
Lytic Dose Strategy
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AMI Transfer Patients 01? 04In-hospital
Mortality by Treatment strategy
Mortality
Year
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Monitoring Outcomes Over Time

• Outcomes are improving
• Explanation of improvement is unclear
• Half-dose lytic regimen
• Expidited care in half-dose group
• Hawthorne effect?
• Still Room for improvement
• Faster transfers
• Better regimens (reduce bleeding)

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DHMC STEMI RegistryConclusions

• useful in assessing the safety and efficacy of
  novel management strategies for STEMI patients
• useful in assessing the impact of new protocols
  over time
• will likely be useful for providing benchmark
  data to individual institutions for QA/QCI

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DHMC STEMI RegistryLimitations

• Enrollment bias - cath lab enrollment will miss
  patients who are not sent to the cath lab
  emergently
• Patients admitted to the initial hospital
• Patients in whom the decision is made not to cath
• Patients who die before they get to cath lab

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DHMC STEMI Registry

• Next Steps
• ER enrollment of all STEMI patients in the region
• Web-based, secure, registry interface
• On-line decision support
• Risk assessment tools
• Guidelines
• Treatment protocols
• Regular feedback to participating ERs/hospitals
• STEMI patient outcomes overall and by treatment
  strategy
• Process metrics (e.g. time intervals)
• Partnership in process improvement
• Novel treatment regimens
• Transfer delay reduction
• Pre-hospital triage??

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• Questions?