1. © 2004 American Heart Association
ACLS
Experienced Provider
Learning Station 1
Case R: R
© 2004 American Heart Association
Overview
This review case is included for EP courses with a need for a basic review of AMI and reperfusion therapy before discussion of the complicated AMI scenarios.
Emphasized is the key concept of early identification of ischemic-type syndromes. Early pain relief and reperfusion are core goals of therapy. Typical ischemic pain is identified and oxygen, aspirin, nitrates and possibly morphine are given as indicated.
The ECG is discussed as central to the diagnosis and early triage of acute ischemic syndromes. Participants are asked to identify and localize major ST-segment elevation MI.
Reperfusion is presented as the early primary treatment priority. Indications for fibrinolytics and contraindications to administration are presented. PCI is discussed as the preferred reperfusion strategy when available (door-to-balloon <90 minutes; experienced operator and high-volume center, surgical availability).
Finally, this case provides an opportunity to explore the participants’ understanding of adjunctive therapy for AMI. The case presents the use of b-blockers, ACE-I inhibitors, and heparin. 1

2. What is your initial management at this time?
Case Progression
After additional history, you conclude that the patient’s pain is ischemic in etiology. She describes the discomfort as 9/10. It has been present for at least one half hour.
Key Concept: Relief of ischemic pain is a priority. The initial general measures include the administration of oxygen, aspirin, and nitroglycerin. Morphine is administered if 3 sublingual nitroglycerin tablets or spray doses have not relieved the ischemic discomfort.
Ask participants to describe initial general treatment of ACS.
The next slide will list these for you in order.
Discussion Points:
All patients with ischemic-type chest pain receive oxygen by nasal cannula at 4/L min. Oxygen is continued during the initial evaluation for 2 to 3 hours. Oxygen can be stopped when the patient is pain-free and oxygen saturation on room air is >90%. Oxygen is continued in patients with overt pulmonary congestion.
Nonenteric aspirin is administered to block platelet activation (unless contraindications are present). A dose of aspirin (162 to 325 mg) is given orally. Alternatively, 4 baby aspirin (81 mg) should be chewed if the patient has not taken aspirin prior to presentation. If the patient has nausea or vomiting, a rectal aspirin suppository (300 mg) is an alternate route of administration.
Nitroglycerin sublingual tablet or spray is administered to this patient every 5 minutes for 3 doses. For continued significant discomfort, morphine is administered and titrated. Physicians may administer an IV -blocker at this point. -blockers are also effective in relieving ischemic pain.
What is your initial management at this time? 3

3. Acute Coronary Syndrome Immediate General Treatment
Oxygen at 4 L/min
Aspirin 162 to 325 mg
Nitroglycerin SL or spray
Morphine IV (if pain not relieved with nitroglycerin)
Key Concept: Relief of ischemic pain is a priority. The initial general measures include the administration of oxygen, aspirin, and nitroglycerin. Morphine is administered if 3 sublingual nitroglycerin tablets or spray doses have not relieved the ischemic discomfort.
Ask participants to describe initial general treatment of ACS.
Discussion Points:
(Note: repeated from previous slide)
All patients with ischemic-type chest pain receive oxygen by nasal cannula at 4 L/min. Oxygen is continued during the initial evaluation, for 2 to 3 hours. Oxygen can be stopped when the patient is pain-free and oxygen saturation on room air is >90%. Oxygen is continued in patients with overt pulmonary congestion.
Nonenteric aspirin is administered to completely block platelet adhesion (unless contraindications are present). A dose of aspirin (162 to 325 mg) is given orally. Alternatively, 4 baby aspirin (81 mg) should be chewed if the patient has not taken aspirin prior to presentation. If the patient has nausea or vomiting, a rectal aspirin suppository (300 mg) is an alternate route of administration.
Nitroglycerin sublingual tablet or spray is administered to this patient every 5 minutes for 3 doses. For continued significant discomfort, morphine is administered and titrated. Physicians may administer an IV -blocker at this point. -blockers are also effective in relieving ischemic pain.
Ask participants what should be given if the patient has hypersensitivity to aspirin or has other contraindications to aspirin therapy. 4

4. Case Progression
Oxygen is initiated. Four 81-mg aspirin, sublingual nitroglycerin, and morphine are given.
A 12-lead ECG has been obtained. Medical command asks for an interpretation.
Key Concept: Acute coronary syndromes regionally affect the heart. That is, occlusion of one of the epicardial coronary arteries reduces flow to a specific region of the heart corresponding to the artery involved. Although highly variable, certain clinical features can occur with infarct location.
Time does not allow a complete or extensive discussion or review of ECG interpretation. Experienced participants will recognize the major infarct locations: anterior (the site of this patient’s MI), inferior, and lateral.
Present the next ECG and ask what it shows. Once participants have identified ST elevation (and new or presumably new left bundle branch block), ask what are the criteria for administration of fibrinolytic therapy for immediate reperfusion of ST-segment elevation MI.
At the end of this case, backup slides are shown for location of MI by ECG presentation. 5

5. Intermediate/low-risk UA
12-Lead ECG Findings
ST elevation or
new or presumably
new LBBB;
strongly suspicious
for injury
ST-elevation MI
(STEMI)
ST depression or
dynamic T-wave
inversion; strongly
suspicious for
ischemia
High-risk unstable
angina/NonST-
elevation MI
(UA/NSTEMI)
Normal or non-
diagnostic changes
in ST segment
or T wave
Intermediate/low-risk UA
Key Concept: Briefly review the principle that the 12-lead ECG is the initial and most important triage tool, and it is abnormal in about 50% of patients with ACS. Stress that the ECG is performed in the prehospital setting or within 10 minutes of ED arrival and interpreted by the senior health professional charged with initiating reperfusion therapy. Discuss the importance of the 3 ECG categories:
ST elevation or new or presumably new LBBB: Time is of the essence and time is muscle. ST-segment elevation MI warrants the reperfusion pathway with door-to-needle time of 30 minutes (fibrinolytics) and door-to-balloon time of 60 to 90 minutes (PCI).
ST depression or dynamic T-wave inversion: These patients DO NOT BENEFIT FROM AND MAY BE HARMED BY the administration of fibrinolytic therapy. In high-risk patients this ECG indicates the need for aggressive antiplatelet therapy (aspirin, heparin, glycoprotein IIb/IIIa inhibitor therapy, clopidogrel) and early coronary angiography. You will discuss this further in CV Case 3.
Normal or nondiagnostic changes in ST segment or T wave: This is a challenging group because most patients DO NOT have ACS, but a significant percentage have CAD and potential unstable syndromes. This group will not be covered in the EP case scenarios.
What is the treatment strategy driven by the above initial ECG criteria? 7

6. Intermediate/low-risk UA
12-Lead ECG Findings
ST elevation or
new or presumably
new LBBB;
strongly suspicious
for injury
ST-elevation MI
(STEMI)
ST depression or
dynamic T-wave
inversion; strongly
suspicious for
ischemia
High-risk unstable
angina/NonST-
elevation MI
(UA/NSTEMI)
Normal or non-
diagnostic changes
in ST segment
or T wave
Intermediate/low-risk UA
Key Concept: Briefly review the principle that the 12-lead ECG is the initial and most important triage tool, and it is abnormal in about 50% of patients with ACS. Stress that the ECG is performed in the prehospital setting or within 10 minutes of ED arrival and interpreted by the senior health professional charged with initiating reperfusion therapy. Discuss the importance of the 3 ECG categories:
ST elevation or new or presumably new LBBB: Time is of the essence and time is muscle. ST-segment elevation MI warrants the reperfusion pathway with door-to-needle time of 30 minutes (fibrinolytics) and door-to-balloon time of 60 to 90 minutes (PCI).
ST depression or dynamic T-wave inversion: These patients DO NOT BENEFIT FROM AND MAY BE HARMED BY the administration of fibrinolytic therapy. In high-risk patients this ECG indicates the need for aggressive antiplatelet therapy (aspirin, heparin, glycoprotein IIb/IIIa inhibitor therapy, clopidogrel) and early coronary angiography. You will discuss this further in CV Case 3.
Normal or nondiagnostic changes in ST segment or T wave: This is a challenging group because most patients DO NOT have ACS, but a significant percentage have CAD and potential unstable syndromes. This group will not be covered in the EP case scenarios.
Reperfusion
Lytics—PCI
Antiplatelet
Antithrombin
Therapy
Risk
Stratification 8

7. ACS—Initial Assessment
Immediate assessment (<10 minutes)
Measure vital signs (check pulses in both arms)
Evaluate oxygen saturation
Establish IV access
Obtain 12-lead ECG
Key Concept: Early reperfusion is key to myocardial salvage, reduction in mortality, and preservation of left ventricular function. Can participants rapidly and effectively determine eligibility for reperfusion strategy (eg, PCI or fibrinolytics) the most important component of the initial immediate assessment?
Ask what the indications and contraindications are for fibrinolytic therapy.
Discussion Points: Participants should know that ST-segment elevation 1 mm in 2 contiguous leads or new or presumably new left bundle branch block is an indication for fibrinolytic therapy.
If participants are uncertain about indications and contraindications, review the fibrinolytic therapy checklist with them. 10

8. Heparin and Fibrinolytics for ST-Segment Elevation MI
Class I: Unfractionated heparin (UFH)
Fibrin-specific fibrinolytics
Initial bolus 60 U/kg (max 4000 U), then
12 U/kg per hour (a maximum bolus of 4000 U and infusion of 1000 U/h for patients weighing >70 kg) UFH as infusion based on aPTT.
Measure aPTT at 3 hours, then q 6 h until stable
aPTT 50 to 70 seconds
Key Concept: Unfractionated heparin is administered to patients undergoing PCI, receiving fibrin-specific fibrinolytics (alteplase, reteplase, tenecteplase), and with nonspecific fibrinolytics (streptokinase, anistreplase, urokinase) at high risk for systemic emboli.
Discussion Point: Summarize current recommendations for heparin use in STEMI—misuse can cause unnecessary ICH. Unfractionated heparin has been used as an adjunct to fibrinolytic therapy, but its use is controversial. Nonselective fibrinolytics induce a systemic coagulopathy and produce large amounts of fibrin-specific degradation products that are anticoagulants. In angiography trials, unfractionated heparin produced higher patency rates. Clinical outcome data (eg, mortality, reinfarction vs bleeding) is not as compelling. General guidelines minimize risk of ICH and bleeding:
Give 60 U/kg (max 4000 U) UFH as initial bolus.
Give 12 U/kg per hour (a maximum bolus of 4000 U and infusion of
1000 U/h for patients weighing >70 kg) UFH as infusion based on
aPTT.
Measure first aPTT 3 hours after administration of fibrinolytic.
Target aPTT range 50 to 70 seconds.
Continue measurement of aPTT every 6 hours until stable. 14

9. Anterior MI—Reperfusion
Now You Know
Identification of ischemic-type chest pain
The initial drug therapy
The importance of triage and early reperfusion for AMI
Risk and benefit of fibrinolytic therapy; cautious use of heparin
The use of adjunctive therapies for AMI
Objectives for Participants
Describes ischemic-type pain
Lists ACS initial assessment steps including drug therapy
Describes 5 Quadrads Approach
Describes ECG triage of ACS/ST-segment deviation
Identifies and localizes MI
Discusses heparin therapy with fibrinolytics and ACS
Describes the use of adjunctive agents with acute MI 18