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Acute Coronary Syndromes . Michelle Welsford, MD, FRCPC Fall Recertification 2004. ACS Overview. Definition Pathophysiology Risk Factors Clinical Features Assessment Management. ACS Definition.
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Acute Coronary Syndromes Michelle Welsford, MD, FRCPC Fall Recertification 2004
ACS Overview • Definition • Pathophysiology • Risk Factors • Clinical Features • Assessment • Management
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 Lumen Lipid Core Fibrous Cap
ACS Pathophysiology Plaque rupture Thrombus formation - Platelet aggregation Thrombus formation - Fibrin cross-linking
Risk Factors • Hypertension • Hyperlipidemia • Diabetes mellitus • Smoking • Family history • Males and post-menopausal women • Advancing 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
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
ACS Management Summary • History/Assessment • Risk factors • EKG • Medical Management