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Learning ObjectivesLearning Objectives
At the end of Case 6 be able to Define acute coronary syndromes Use the Ischemic Chest Pain Algorithm Consider the Why? (actions), When? (indications),
How? (dose), and Watch Out! (precautions) of medications for ischemic chest pain patients
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Learning Objectives (cont’d)Learning Objectives (cont’d)
At the end of Case 6 be able to Recognize significant ST-segment changes Know how to measure ST-segment elevation
and depression Know basic principles of anatomic localization of
infarct, injury, and ischemia Know how to use the ECG to risk-stratify patients
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Case 1Case 1
A 55-year-old man presents with a chief complaint of severe (10 of 10) substernal chest pain. He has pain radiating down his left arm and up into his jaw, nausea, and a profound sense of impending doom. He is covered with small beads of sweat.
Vital signs: TEMP = 37.2°C; HR = 110 bpm; BP = 150/100 mm Hg; RESP = 12
Describe your immediate assessment.Describe your immediate general treatment.
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Ischemic Chest Pain AlgorithmIschemic Chest Pain Algorithm
Immediate assessment (<10 minutes)• Measure vital signs (automatic/standard BP cuff)• Measure oxygen saturation• Obtain IV access• Obtain 12-lead ECG (physician reviews)• Perform brief, targeted history and physical exam;
focus on eligibility for fibrinolytic therapy• Obtain initial serum cardiac marker levels• Evaluate initial electrolyte and coagulation studies• Request, review portable chest x-ray (<30 minutes)
Chest painsuggestive of ischemia
Immediate general treatment• Oxygen at 4 L/min• Aspirin 160 to 325 mg• Nitroglycerin SL or spray• Morphine IV (if pain not relieved with
nitroglycerin)
Memory aid: “MONA” greetsall patients (Morphine, Oxygen, Nitroglycerin, Aspirin)
EMS personnel canperform immediateassessment and treat-ment (“MONA”),including initial 12-lead
ECG and review forfibrinolytic therapyindications andcontraindications.
Assess initial 12-lead ECG
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Items of Immediate Assessment (<10 min) Items of Immediate Assessment (<10 min)
Check vital signs with automatic or standard BP cuff Determine oxygen saturation Obtain IV access Obtain 12-lead ECG Obtain a brief, targeted history and perform a physical
examination; use checklist (yes-no); focus on eligibility for fibrinolytic therapy
Obtain blood sample for initial cardiac marker levels Initiate electrolyte and coagulation studies
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Immediate General TreatmentImmediate General Treatment
Oxygen at 4 L/min Aspirin 160 to 325 mg Nitroglycerin SL or spray Morphine IV (if pain not relieved
with nitroglycerin)
Review the Why? (actions), When? (indications), How? (dose), and Watch Out! (precautions) of these medications to consider in patients with ischemic chest pain.
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Medications Used in ACLSMedications Used in ACLS
Why? (Actions) When? (Indications) How? (Dose) Watch Out! (Precautions)
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Oxygen Used in Acute Coronary Syndromes
Oxygen Used in Acute Coronary Syndromes
Why? Increases supply of oxygen to ischemic tissueWhen? Always when AMI is suspectedHow? Start with nasal cannula at 4 L/min Remember one word: oxygen-IV-monitorWatch Out! Rarely COPD patients with hypoxic
ventilatory drive will hypoventilate
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Nitroglycerin: ActionsNitroglycerin: Actions
Decreases pain of ischemia Increases venous dilation Decreases venous blood return to heart Decreases preload and cardiac
oxygen consumption Dilates coronary arteries Increases cardiac collateral flow
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Nitroglycerin: IndicationsNitroglycerin: Indications
Class I: First 24 to 48 hours in patients with ST-segment elevation or depression including• LV failure (acute pulmonary edema or CHF)• Elevated BP (especially with signs of LV failure)• Large anterior infarction• Persistent ischemia
Suspected ischemic chest pain Unstable angina (change in angina pattern) Acute pulmonary edema (if BP >90 mm Hg systolic)
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Nitroglycerin: DoseNitroglycerin: Dose
Sublingual: 0.3 to 0.4 mg; repeat every 5 minutes Spray inhaler: 2 metered doses at 5-minute intervals IV infusion: 12.5 to 25 g bolus, 10 to 20 g/min
infusion, titrated
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Nitroglycerin: PrecautionsNitroglycerin: Precautions
Use extreme caution if systolic BP <90 mm Hg Use extreme caution in RV infarction
– Suspect RV infarction with inferior ST changes Limit BP drop to 10% if patient is normotensive Limit BP drop to 30% if patient is hypertensive Watch for headache, drop in BP, syncope,
tachycardia Tell patient to sit or lie down during administration
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Morphine Sulfate: Actions, IndicationsMorphine Sulfate: Actions, Indications
Why? (Actions)• To reduce pain of ischemia• To reduce anxiety• To reduce extension of ischemia by reducing
oxygen demands When? (Indications)
• Continuing pain• Evidence of vascular congestion (acute pulmonary edema)• Systolic blood pressure >90 mm Hg• No hypovolemia
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Morphine Sulfate: Dose, Precautions
Morphine Sulfate: Dose, Precautions
How? (Dose)
• 2 to 4 mg titrated to effect
• Goal: Eliminate pain Watch out for (Precautions)
• Drop in blood pressure, especially in patients with
– Volume depletion
– Increased systemic resistance
– RV infarction
• Depression of ventilation
• Nausea and vomiting (common)
• Bradycardia
• Itching and bronchospasm (uncommon)
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Aspirin: ActionsAspirin: Actions
Why? (Actions)
• Blocks formation of thromboxane A2 (thromboxane A2 causes platelets to aggregate and arteries to constrict)
These actions will reduce• Overall mortality from AMI• Nonfatal reinfarction• Nonfatal stroke
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Aspirin: Indications, Dose, Precautions
Aspirin: Indications, Dose, Precautions
When? (Indications) As soon as possible!• Standard therapy for all patients with new pain suggestive
of AMI• Give within minutes of arrival
How? (Dose) 160- to 325-mg tablet taken as soon as possible Watch Out! (Precautions)
• Relatively contraindicated in patients with active peptic ulcer disease or asthma
• Contraindicated in patients with known aspirin hypersensitivity• Bleeding disorders• Severe hepatic disease
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Assess Initial 12-Lead ECG Findings
Assess Initial 12-Lead ECG Findings
Classify patients with acute ischemic chest pain into
1 of the 3 groups above within 10 minutes of arrival.
• ST elevation or new or presumably new LBBB:
strongly suspicious for injury
• ST-elevation AMI
• ST depression or dynamicT-wave inversion:
strongly suspicious for ischemia
• High-risk unstable angina/non–ST-elevation AMI
• Nondiagnostic ECG:absence of changes in ST segment or T waves
• Intermediate/low-riskunstable angina
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Recognition of AMI Recognition of AMI
Know what to look for—• ST elevation >1 mm• 3 contiguous leads
Know where to look• Refer to 2000 ECC
HandbookPR baseline
ST-segment deviation= 4.5 mm
J point plus0.04 second
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How to MeasureST-Segment Deviation
How to MeasureST-Segment Deviation
PR baseline
J point plus0.04 second
ST-segment deviation
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12-Lead ECG Variations in AMI and Angina
12-Lead ECG Variations in AMI and Angina
Baseline
Ischemia—tall or inverted T wave (infarct),ST segment may be depressed (angina)
Injury—elevated ST segment, T wave may invert
Infarction (Acute)—abnormal Q wave,ST segment may be elevated and T wavemay be inverted
Infarction (Age Unknown)—abnormal Q wave,ST segment and T wave returned to normal
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AMI LocalizationAMI Localization
aVF inferiorIII inferior V3 anterior V6 lateral
aVL lateralII inferior V2 septal V5 lateral
aVRI lateral V1 septal V4 anterior
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ß-Blockersß-Blockers
Mechanism of action• Blocks catecholamines from binding to
ß-adrenergic receptors• Reduces HR, BP, myocardial contractility • Decreases AV nodal conduction • Decreases incidence of primary VF
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ß-Blockersß-Blockers
Severe CHF/PE SBP <100 mm Hg Acute asthma
(bronchospasm) 2nd- or 3rd-degree
AV block
Mild/moderate CHF HR <60 bpm History of asthma IDDM Severe peripheral
vascular disease
AbsoluteContraindications Cautions
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HeparinHeparin
Mechanism of action• Indirect thrombin inhibitor (with AT III)
Indications• PTCA or CABG• With fibrin-specific lytics • High risk for systemic emboli
– Conditions with high risk for systemic emboli, such as large anterior MI, atrial fibrillation, or LV thrombus
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ACE InhibitorsACE Inhibitors
Mechanism of action• Reduces BP by inhibiting angiotensin-converting
enzyme (ACE)• Alters post-AMI LV remodeling by inhibiting
tissue ACE• Lowers peripheral vascular resistance
by vasodilatation• Reduces mortality and CHF from AMI
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Fibrinolytic TherapyFibrinolytic Therapy
Breaks up the fibrin network that binds clots together Indications: ST elevation >1 mm in 2 or more contiguous
leads or new LBBB or new BBB that obscures ST• Time of symptom onset must be <12 hours • Caution: fibrinolytics can cause death from brain
hemorrhage Agents differ in their mechanism of action, ease of preparation
and administration; cost; need for heparin 5 agents currently available: alteplase (tPA, Activase),
anistreplase (Eminase), reteplase (Retavase), streptokinase (Streptase), tenecteplase (TNKase)
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Antiplatelet AgentsAntiplatelet Agents
Blocks glycoprotein IIb/IIIa receptors on platelets
Blocked receptors cannot attach to fibrinogen
Fibrinogen cannot aggregate platelets to platelets
Indications: ACS with NO ST-segment elevation:• Non–Q-wave MI• Unstable angina managed medically• UA undergoing PCI
Examples: abciximab (ReoPro), eptifibitide (Integrilin), tirofiban (Aggrastat)
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Percutaneous Transluminal Coronary Angioplasty
Percutaneous Transluminal Coronary Angioplasty
Direct treatment Mechanical reperfusion
of infarct-related coronary artery
Best outcome achieved for patients with AMI plus cardiogenic shock