Transcript The Management of AMI and ACS Patients in the Emergency Department Part 2: AMI/ACS Treatment.

The Management of
AMI and ACS Patients
in the Emergency
Department
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Part 2:
AMI/ACS Treatment
2
Acute Myocardial
Infraction Part II:
Reperfusion Therapies
for UA, NSTEMI,
and STEMI
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Edward P. Sloan, MD, MPH, FACEP
Professor
Department of Emergency Medicine,
University of Illinois at Chicago
Chicago, IL
([email protected])
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Attending Physician
Emergency Medicine
University of Illinois Hospital
Our Lady of the Resurrection
Medical Center
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Global Objectives
Learn more about AMI and ACS
 Increase awareness of Rx options
 Enhance our ED management
 Improve patient care & outcomes
 Maximize staff & patient satisfaction
 Be prepared for the EM board exam

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Session Objectives
Provide AMI, ACS overview
 Ask clinically relevant questions
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AMI/ACS Rx:
Global Objectives
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AMI/ACS Rx: Objectives

What are the global objectives of
AMI Rx in the ED?
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AMI/ACS Rx: Objectives
Maximize coronary dilatation and
myocardial O2 delivery
 Minimize myocardium O2 demand

Achieve TIMI-III coronary flow
 Minimize myocardium damage
 Minimize chronic LV dysfunction
 Prevent dysrhythmias, sudden death
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AMI/ACS Rx:
Pharmacological
Interventions
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Pharmacotherapy of AMI/ACS
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ASA
NTG
Morphine
Heparin, LMW
Thrombolytics
Antidysrhythmics
Fluid & pressure therapies
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AMI/ACS Rx: Oxygen
AMI/ACS
 Limited O2 delivery
 Increased myocardial O2 use
 IV, O2, monitor
 NC at 4 L/min
 Quick, easy, cheap
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AMI Rx: ASA, Platelet Meds

When are ASA and other platelet
meds indicated?
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AMI/ACS Rx: Aspirin
ISIS 2: as good as streptokinase
 Decreased platelet aggregation
(Tbx A2)
 160-325 mg ASAP
 High dose: prostacyclin
production decreases, with
decreased benefits
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AMI/ACS Rx: Aspirin
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All AMI/ACS pts should get ASA

Dose of 162 mg reduces
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mortality by 23%
reinfarction by 49%
stroke by 46%
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AMI/ACS Rx: Platelet Rx
Dipyridamole
 Ticlopidine
 Clopidogrel
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Consider when ASA allergic
 Caution in acute setting!
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AMI/ACS Rx: Nitrates
When are nitrates indicated?
 What is the appropriate dose of
NTG in AMI/ACS patients?
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AMI/ACS Rx: Nitrates
Coronary dilation
 Increased collateral flow
 Decrease preload, myocardial O2 use
 SL 1/150, 1/400
 Spray, paste, IV
 SL rarely causes critical hypotension
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AMI/ACS Rx: Nitrates
SL NTG 1/150
 400 ucg q 5 minutes
 80 ucg per minute
 Good bioavailability
 NTG drip: can start at > 10 ucg/min
 Critical hypotension reversible
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AMI/ACS Rx: Nitrates
Expect SBP to drop with NTG
 SBP drop 10% with normal BP
 SBP drop 30% with elevated BP
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AMI/ACS Rx: Nitrates
Caution with RV infarction!
 Reduces preload & LV filling
 Reduces cardiac output
 Hypotension can occur
 Must still maximize O2 delivery
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Can reduce mortality by 35%
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AMI/ACS Rx: Morphine

What are the indications for
morphine in AMI/ACS patients?
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AMI/ACS Rx: Morphine
Provides analgesia
 Reduces central sympathetic output
 May  myocardial O2 consumption
 May mask ongoing ischemia??
 Risk/benefit favors use
 Use with marked pain and anxiety
 2-5 mg IVP
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AMI/ACS: Antidysrhythmics

What are the indications for
antidysrhythmics in AMI/ACS
patients?
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AMI/ACS Rx: VT, VF Rx
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VF: Shock at 200j, 300j, 360j, unsynch
VT (Polymorphic, unstable): same
VT (Monomorphic, unstable): 100j, synch
VT (Monomorphic, stable):
 Amiodarone: 150-300 slow IVP
 Lidocaine: 1-1.5 mg/kg bolus injection
 Procainamide: 12-17 mg/kg, 20-30/min
 Synch cardioversion, 50j, 100j
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Monomorphic VTach
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Polymorphic VTach
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AMI/ACS Rx: AFib Rx
Cardioversion: unstable patients
 Rapid digitalization
 IV Beta blockers
 Diltiazem or verapamil
 Heparin
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Atrial Fibrillation
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AMI/ACS Rx: Adenosine
Slow conduction thru AV node
 Interrupts reentrant pathways
 Used in PSVT
 6 mg IVP, then 12 mg IVP
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Paroxysmal SVT
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AMI/ACS Rx: Amiodarone
Class III agent
 Treats supraventricular and
ventricular dysrhythmias
 Prolongs refractory period
 Sustained monomorphic VT
 VF and unstable VT
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AMI/ACS Rx: Atropine
Sinus brady, poor perfusion, PVCs
 Sinus brady, low SBP after NTG
 Inferior AMI with high grade block
 Inferior AMI, symptomatic brady
 N/V after morphine
 EMD, with epinephrine
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AMI/ACS Rx: Beta-blockade
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What are the indications for betablockade in AMI/ACS patients?
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AMI/ACS Rx: Beta-blockade
Ischemic penumbra preserved
 Decreased catecholamines
 Decreased dysrhythmias
 Decreased HR and BP
 Decreased infarct size
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AMI/ACS Rx: Beta-blockade
Consider in all AMI and ACS pts
 Continued, recurrent ischemic pain
 Tachyarrhythmias: rapid AFib, Flutter
 May even be useful in patients with
relative contraindications
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Metoprolol 5mg IV q5mx3
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Within 12 hours of presentation
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AMI/ACS Rx: Beta-blockade
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Contraindications
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Moderate to severe CHF
COPD/asthma
Bradycardia
Hypotension
2nd or 3rd degree A-V blocks
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AMI/ACS Rx: Beta-blockade
Not consistently achieved in AMI
 Why do clinicians defer this Rx?

May be optimal with HTN, tachycardia
 With HR < 80, normal BP, less use
 Not mandated in the ED, prior to PCI
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AMI/ACS Rx:
++
Ca
Channel
Rate control in atrial fib, flutter
 If unable to provide beta blockade
 Not viewed in same way a use of
metoprolol in AMI
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AMI/ACS Rx: Digitalis
Rapid load in rapid atrial fibrillation
 Provided before beta blocker use
 Not used for its inotropic effects
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AMI/ACS Rx: Lidocaine
Limited use
 New, symptomatic VT
 Malignant dysrhythmias, VF
 1-1.5 mg/kg, 2-4 mg/min drip
 Caution in ventricular escape rhythm
 Can cause asystole
 No real prophylactic use
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AMI/ACS Rx: Magnesium
Documented Mg deficit with diuretics
 Prolonged QT, torsade de pointes VT
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1-2 gram bolus over 5 minutes
 Empiric therapy in refractory VF?
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Torsade de Pointes
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AMI/ACS: BP/Fluid Rx
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How should BP and fluids be
managed in AMI/ACS patients?
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AMI/ACS Rx: IV Fluids
What are the indications for an
acute fluid bolus?
 When should large volumes of
IVF be infused in a hypotensive
AMI/ACS patient?
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AMI/ACS Rx: IV Fluids
Normal saline
 Bolus hypotensive pts
 Starling curve supports use
 200 cc even with CHF
 RV AMI: Repeated boluses
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AMI/ACS Rx: IV Fluids
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AMI/ACS Rx: Dopamine
Dopamine useful in ED
 Enhanced vital organ flow
 Supports nitrates with labile BP
 Increases HR, SVR, cardiac O2 use
 Increased inotropy
 Ischemia, dysrhythmias can occur
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AMI/ACS Rx: Dobutamine
Dobutamine can also be used in ED
 Pulmonary edema, LV dysfunction
 No endogenous norepi release
 Less myocardial O2 use increase
 Improved inotropy
 Improved coronary artery flow
 Can be used with dopamine
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AMI/ACS Rx: Norepinephrine
Used in refractory hypotension
 No response to other pressors
 Increased myocardial O2 use
 Improved inotropy, but no increase in
cardiac output as SVR is increased
 Ectopy, dysrhythmias can occur
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AMI/ACS Rx: Inotropes
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AMI/ACS Rx: Diuretics
Furosemide: NaCl clearance
 Used in pulmonary edema & LV
dysfunction
 Volume, Starling effects
 More optimal LV filling, stroke
volume, and cardiac output
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AMI/ACS Rx: ACE Inhibitors
Reduces LV dilatation and
dysfunction, improves remodeling
 Slows development of CHF
 AMI/ACS patients, especially
critically ill anterior wall MI patients
with pulmonary edema show
greatest benefit
 Captopril, enalapril, or lisinopril
 Early use may reduce mortality
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AMI/ACS Rx: ACE Inhibitors
Not mandated to be ED Rx
 Contraindications
 Hypotension
 Bilateral renal artery stenosis
 Renal insufficiency/failure
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AMI/ACS Rx: Clot Therapies
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What are the indications for
heparin, IIb/IIIa, and thrombolytic
therapy?
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AMI/ACS Rx: Heparin (LMW)
What are the indications for
heparin and LMW heparin in
AMI/ACS patients?
 How does LMW heparin work
differently than un-fractionated
heparin?
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AMI/ACS Rx: Heparin (LMW)
Prevents late thrombus formation
 Maintains patent coronary artery
 Prevents mural thrombus from
forming in anterior wall MI
 Prevents cerebral emboli with AMI
 Doesn’t Rx already formed thrombi
 Platelet Rx: White clot, ACS, NSTEMI
 Thrombolytic Rx: Red clot, STEMI
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AMI/ACS Rx: Heparin (LMW)
Thrombin inhibition
 Prevents clot propagation, formation
 High embolism risk pts identified:
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Large or ant MI, Afib, previous
embolus, known LV thrombus
Complication reduction:
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Reinfarction reduced by 30%
Mortality reduced by 21%
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AMI/ACS Rx: Heparin (LMW)
Indicated in patients with PCI or
surgical revascularization
 Also used in pts who get tPA
and those with ACS, NSTEMI
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AMI/ACS Rx: Heparin
Over 1300u/hr associated with
bleeding complications
 Attempt to achieve a PTT that
is 1.5-2.0 times normal (60-85
seconds)
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AMI/ACS Rx: Heparin
Bolus: 60 units/kg
 Infusion: 12 U/kg per hour
 Max recommended dose
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4000 units bolus
1000 units per hour infusion
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AMI/ACS Rx: LMW Heparin
Similar indications to heparin
 1 mg/kg SQ BID
 Prior suggestion that heparin
preferred in highest risk pts
 Some prefer heparin prior to PCI
 No demonstrated difference between
heparin and LMW in these patients
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AMI/ACS Rx: IIb/IIIa Inhibitors
What are the indications for
IIb/IIIa inhibitors in AMI/ACS
patients?
 How do these drugs work?
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AMI/ACS Rx: IIb/IIIa Inhibitors
Abciximab (ReoPro): long acting Ab
 Eptifibatide (Integrillin): peptide
 Tirofiban (Aggrastat): peptide
 Used in ACS, NSTEMI patients,
especially those who undergo PCI
 High risk patients (positive troponin)
 Requires 48-72 hrs of infusion to
demonstrate benefits
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AMI/ACS Rx: IIb/IIIa Inhibitors
Useful in treatment of pts with
refractory unstable angina
 Treats white clot: ACS, NSTEMI
 Few head to head studies that
compare IIb/IIIa inhibitors
 Rate of ICH lower than with
fibrinolysis
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AMI/ACS Rx: IIb/IIIa Inhibitors
50,000 receptors per platelet
 Final common pathway
 Platelets bind with fibrinogen
 Forms hemostatic plug (white clot)
 IIb/IIIa glycoprotein prevents this
binding and formation of white clot
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Platelet Activation
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AMI/ACS Rx: IIb/IIIa Inhibitors
Inhibit 80% of receptors, then there is
no platelet aggregation
 Prevents ongoing platelet deposition
 No effect on thrombin generation
 No effect on coagulation, inflammation
 Combo therapy with thrombin drugs
 Use with heparin is indicated
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White Clot: ACS, NSTEMI
•
Platelets, Fibrin, Red Cells
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AMI/ACS Rx: IIb/IIIa Inhibitors
Beneficial effects of platelet inhibition
 Decreased re-occlusion after
thrombolysis and/or PCI
 Decreased re-infarction risk because
of better coronary artery healing
 Minimizes extent of occlusion as a
result of acute plaque disruption
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AMI/ACS Rx: IIb/IIIa Inhibitors
Clinical use in ED is indicated in ACS
 Actual use is somewhat limited by
availability of PCI for most critically ill
ACS, NSTEMI patients
 Although use should begin in ED,
many cardiologists begin infusion
following PCI
 Still important prior to transfer for PCI
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AMI/ACS Rx: Thrombolytics
What are the indications for
thrombolytic therapy in AMI/ACS
patients?
 How do thrombolytics work?
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Red Thrombus in STEMI
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Thrombin, fibrin, clotting factors
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AMI/ACS Rx: Thrombolytics
Time is muscle
 Restoration of TIMI-3 flow
 Myocardial salvage
 Reduced ventricular dysfunction
 Reduced ectopy
 Sudden death less likley
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AMI/ACS Rx: Thrombolytics
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Indications
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Classic history
EKG with > 1mm ST  in 2 limb
leads or > 2mm ST  in > 2
precordial leads
New LBBB
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AMI/ACS Rx: Thrombolytics
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No contraindications
No cardiogenic shock (??)
Presentation within 12 hours
of symptom onset
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AMI/ACS Rx: Thrombolytics
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Maximal benefit when given
within first 2 hours of infarct
Greater mortality benefit in
patients with anterior wall AMI
as opposed to those with
inferior wall AMI
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AMI/ACS Rx: Thrombolytics
Streptokinase
 APSAC
 tPA
 Retavase (rPA)
 TNK t-PA
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AMI/ACS Rx: Thrombolytics
tPA
Clot specific
 Not antigenic
 Reduces mortality 28%
 ½ life only 5 minutes
 Higher risk of ICH than SK
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AMI/ACS Rx: Thrombolytics
tPA
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Dosing:
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15 mg IV over 2 min
0.75 mg/kg (max 50) over 30 min
0.50 mg/kg (max 35) over 60 min
Start heparin, ASA concurrently
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AMI/ACS Rx: Thrombolytics
Retavase (rPA)
At least as effective as SK
 Comparable tPA mortality benefit
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Dosing: 10mg IV bolus at 0 min
and 30 min
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AMI/ACS Rx: Thrombolytics
TNK t-PA
Genetic variant of tPA
 Slower plasma clearance
 Greater fibrin specificity
 0.53 mg/kg bolus, 50mg max
 Heparin infusion, ASA use
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AMI/ACS Rx: Thrombolytics
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Absolute contraindications
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Any active bleeding
Recent GI bleed (within 10
days)
Hemorrhagic CVA at any time
Non-hemorrhagic CVA in last 6
months
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AMI/ACS Rx: Thrombolytics
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Absolute contraindications
Aortic dissection
 Pericarditis
 Childbirth within 10 days
 HTN (SBP >200 or DBP>120)
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AMI/ACS Rx: Thrombolytics
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Absolute contraindications
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Intracranial/spinal mass lesion,
aneurysm, AV malformation
Surgery within 2 months
Serious head trauma in last month
Bleeding disorder
Pregnancy
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AMI/ACS Rx: Thrombolytics
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Relative Contraindications
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Traumatic CPR
PUD
Current anticoagulant use
Hx of HTN with DBP > 100
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AMI/ACS Rx: Thrombolytics
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Relative contraindications
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Diabetic/hemorrhagic retinopathy
Non-compressible vein cannulation
Over age 70
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AMI/ACS Rx:
Mechanical
Interventions
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AMI/ACS Rx: Cardiac Pacing

What are the indications for
cardiac pacing in AMI/ACS
patients?
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AMI/ACS Rx: Cardiac Pacing
For large anterior STEMIs
 Not as an Rx for vagal reaction
 To Rx symptomatic bradycardia
 Overdrive suppression (+/-)
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AMI/ACS Rx: Cardiac Pacing
Transcutaneous Cardiac Pacing
Sinus brady, low BP, no Rx effect
 Mobitz type II second degree block
 Third degree block
 Bifascicular block
 LBBB
 RBBB or LBBB & first degree AV block
 Less so for stable bradycardia, RBBB
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AMI/ACS Rx: Cardiac Pacing
Transvenous Cardiac Pacing
Asystole
 Sinus brady, low BP, no Rx effect
 Mobitz type II second degree block
 Third degree block
 Bifascicular block
 RBBB & first degree AV block (+/-)
 Overdrive suppression for VT (+/-)
 3 sec sinus pauses, no Rx effect (+/-)
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AMI/ACS Rx: Cardiac Pacing
Cardiac Pacing Approach
Establish rhythm disturbance
 Determine that rate, rhythm are
effecting adequate perfusion
 Attempt to Rx BP
 Attempt to improve rate with atropine
 Attempt transcutaneous pacing
 Place sheath for transvenous pacer
 Insert transvenous pacer as needed
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AMI/ACS Mechanical Interventions
Mechanical Ventilation
Intubation, mechanical ventilation
 Decreased work of breathing
 Increases BP (hopefully)
 Decreases myocardial O2 use
 Increases O2 delivery (CHF)
 Critical in cardiogenic shock
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AMI/ACS Mechanical Interventions
Intraaortic Balloon Pump
What are the indications for
intraaortic balloon pump support
in AMI/ACS patients?
 How does the intraaortic balloon
pump work?
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AMI/ACS Mechanical Interventions
Intraaortic Balloon Pump
Refractory cardiogenic shock
 Fluids, pressors without effect
 Persistent pain, shock
 Rapid systole balloon deflation
 Vacuum assists LV function
 Improves cardiac output
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AMI/ACS Mechanical Interventions
Intraaortic Balloon Pump
Refractory cardiogenic shock
 As a stabilizing measure prior to PCI
 Acute mitral regurgitation, VSD
(STEMI mechanical complications)
 Intractable ventricular dysrhythmias
 Refractory post-MI ischemia, as bridge
 Unstable pts when LV is “at risk” (+/-)
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AMI/ACS Mechanical Interventions
Percutaneous Coronary Interventions
What is PCI?
 What are the PCI indications?
 What is the goal of PCI?
 Over what time period should
revascularization occur?
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AMI/ACS Rx: Revascularization
Over what time period should
revascularization occur?
 ACEP and AHA/ACC guidelines
 120 minutes door to balloon time
 If not, consider tPA use in ED
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AMI/ACS Mechanical Interventions
Percutaneous Coronary Interventions
PCI optimal for single lesion, grafts
 May be able to treat multiple lesions
 May require multiple procedures
 Extensive small vessel disease
precludes effective PCI Rx
 Multiple occluded vessels: CABG
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AMI/ACS Mechanical Interventions
Percutaneous Coronary Interventions
PCI is the industry standard
 Door to balloon time can be > 120 min
 When PCI is imminent:
 Front loaded tPA not often utilized
 IIb/IIIa inhibitors not often utilized
 Need to optimize ED process
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AMI/ACS Rx: EMS Triage

Is there evidence to support
directed triage to “cardiac”
centers?
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AMI/ACS Rx: EMS Triage
Is there evidence to support directed
triage to “cardiac” centers? No.
 It is unclear that door to balloon time
is significantly decreased, nor is
patient outcome worsened if a
transfer agreement is in place
 Caveat: cardiogenic shock patients
probably would benefit from direct
triage for immediate PCI
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AMI/ACS Rx: Pre-hospital Rx

What out-of-hospital therapies
have been demonstrated to
improve outcome in AMI?
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AMI/ACS Rx: Pre-hospital Rx
911 activation
 Early defibrillation, first responders
 12 lead EKG, thrombolysis (+/-)

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AMI/ACS: Specific Issues
Elderly and females
associated with more atypical
presentations
 Pts with symptoms of
AMI/ACS after PCI should be
assumed to have abrupt
vessel closure

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AMI/ACS: Hospital Admission
Pts at high risk for CAD, AMI, or
death admit to ICU
 ED observation units and non-ICU
monitored beds are safe for pts
with normal ECGs and low to
moderate risk
 Low risk patients: 2 hour rule out
and outpatient stress testing

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History
Case #1
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58 year old male
Chest pain, sub-sternal, severe
Onset less than one hour prior
Nausea, diaphoresis
No known cardiac history
Smoker, ?cholesterol
109
Px
Case #1
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98.8 100/60 110 24
Gen: Screaming in pain, diaphoretic
Chest: BS equal
CV: Reg rhythm without
110
111
112
Diagnosis
Case #1
Having the big one.
 Acute anterior wall MI
 Complete occlusion of the left main
coronary artery

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Treatment
Case #1
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
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IV NTG
ASA, Oxygen
Morphine
Heparin
Cardioversion (200j) (VTach)
Rapid transfer for PTCA
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History
Case #2
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
48 year old male
Sudden onset of chest pain
SOB, nausea
? Cardiac hx, on ASA
115
Px
Case #2
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
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
98.6 160/90 116 24
Gen: Diaphoretic, pale, anxious
Chest: Clear BSBE
CV: Reg without
Exam otherwise normal
116
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119
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Diagnosis
Case #2
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
Inferior wall MI
Likely R coronary artery occlusion
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Treatment
Case #2
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
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
IV NTG
ASA, Oxygen
Morphine
Heparin
Rapid transfer for PTCA
122
Conclusions
AMI/ACS Rx in the E.D.
Common problem
 ED staff has an important role
 Many therapies are available
 Chance to make a difference
 Good guidelines exist
 Interested consultants

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Conclusions
AMI/ACS: Relevant Questions
Is there an acute plaque rupture?
 Is this ACS (white clot) req platelet Rx?
 Is this STEMI (red clot) req TT, PCI?
 What Rx must be provided in the ED?
 How can revascularization best be
achieved given the ED processes?

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AMI/ACS Diagnosis
Questions?
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2002, 2004 ACC/AHA guidelines
www.acc.org or www.americanheart.org
2000 ACEP guidelines
www.acep.org
www.guidelines.gov
PDF file allows for optimal printing
[email protected] (312) 413-7490
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