acute coronary syndromes michelle welsford, md, frcpc fall recertification 2004
TRANSCRIPT
Acute Coronary Syndromes
Michelle Welsford, MD, FRCPCMichelle Welsford, MD, FRCPC
Fall Recertification 2004Fall Recertification 2004
ACS Overview
DefinitionPathophysiologyRisk FactorsClinical FeaturesAssessmentManagement
ACS Definition
Myocardial ischemia: insufficient blood supply to the heart muscle that results from coronary artery disease
ACS: Any group of symptoms compatible with myocardial ischemia.
Represent a continuum of the same disease process:– Angina– Unstable angina– Non-ST elevation MI– STEAMI
ACS Pathophysiology
All ACS - sudden ischemia that cannot be differentiated initially
Three common events:– Plaque rupture– Thrombus formation– Vasoconstriction
Lipid Core
Fibrous Cap
Lumen
ACS Pathophysiology
Plaque rupture
Thrombus formation - Fibrin cross-linking
Thrombus formation - Platelet aggregation
Risk Factors
HypertensionHyperlipidemiaDiabetes mellitusSmokingFamily historyMales and post-menopausal
womenAdvancing age
Clinical Features
Typical
Atypical – 25% of all AMIs – Pleuritic or sharp/stabbing CP– Palpable CP (10-33% AMI)– Arm pain only– Indigestion – SOB only (40% in elderly)– “Dizziness” (5% AMI)– Nausea – Syncope
Assessment – Examination
Exam usually normal (85%) May have:
– Diaphoresis – Extra heart sounds
(S3, S4 or rubs)– Dysrhythmias– Evidence of new or
worsening heart failure– Hypotension
Assessment – EKG
12-lead EKG– May be normal in ACS– May be nonspecific: ST or T wave ischemic changes– May be suspicious for injury: ST elevation
STEAMI– Fibrinolytic checklist
EKG - AMI Diagnosis
AMI Diagnosis:– At least 2 of 3 criteria
Clinical history suggestive of AMI EKG criteria Laboratory diagnosis
EKG criteria– ST elevation 1 mm or more in 2 anatomically
contiguous leads– OR BBB
EKG - Contiguous Leads
I aVR V1 V4
II aVL V2 V5
III aVF V3 V6
Limb Leads Chest Leads
EKG - AMI Imitators
Causes of ST elevation– AMI– LVH– BBB– Ventricular beats – PVCs – Pericarditis– Early repolarization– Others
EKG Practice 1
EKG Practice 2
EKG Practice 3
EKG Practice 4
Management – Prehospital
Prehospital– Oxygen– ASA– Nitro– Morphine– Dysrhythmia treatment
Medication Defibrillation
– 12-lead EKG with notification of receiving hospital
– Prehospital thrombolysis– Triage to PCI facility
Management – Hospital
Hospital– Oxygen, ASA, Nitro,
Morphine– Dysrhythmia management– Anticoagulation - heparin – Reperfusion
Fibrinolysis PCI - percutaneous
coronary intervention
History/Assessment Risk factorsEKG Medical Management
ACS Management Summary
Questions ?