As described in the hypertension post I start with my notes - sources from medical text books
The phrase Acute Myocardial Infarction - is ambiguous and i read three related chapters in the text book and summarized them as my notes below
Chronic Stable Angina, Unstable Angina, Non ST Segment Elevation of Myocardial Infraction, ST Elevation Myocardial Infarction
Chronic Stable Angina, Unstable Angina, Non ST Segment Elevation of Myocardial Infraction, ST Elevation Myocardial Infarction
Chronic Stable Angina:
Overview:
most common clinical manifestation of coronary artery disease (CAD) - imabalnce between myocardial metabolic O2 demand vs supply commonly because of atherosclerotic coronary artery obstruction.
Presentation:
Associated with exertion or emotional upset
Relieved quickly by rest or nitroglycerinAssessment:
History of established risk factors: Cigarette smoking, hypertension, hypercholesterolemia, diabetes, obesity
EKG - maybe normal
Stress testing - Exercise vs IV dipyridamole - radionuclide/EKG/MRI vs.
Coronary arteriography - in many
Plan:
Outpatient management
Identify and manage risk factors (Cigarette smoking, hypertension, hypercholesterolemia, diabetes, obesity)
Aspirin 81-162mg/d +/- ACE inhibitor
Acute: sublingual nitroglyerin q5min
Long term: long-acting nitrates, beta blockers, calcium anntagonists, ranolazine
Mechanical revascularization - percutaneous coronar intervention with stent if stenosis, coronary artery bypass graft
Prognosis:
Maybe self limited or progress to unstable angina/myocardial infarction if not managed.
Unstable Angina and Non ST Elevation Myocardial Infarction
Overview:
UA and NSTEMI are similar in mechanism, presentation and management - and considered part of spectrum
NSTEMI is UA with evidence of myocardial tissue injury (necrosis/death e.g. elevated cardiac biomarkers)
Presentation:
New onset severe angina (more than usual), angina at rest/minimal exertion, recent change in angina pattern.
Different from STEMI by EKG - no ST elevation, no Q wave changes
Assessment:
All: nitoglycerin, beta blockers
Plan:
Hospitalize - except in very low risk
Low risk of NSTEMI: serial EKR and biomarkers +/- anti thrombotic therapy + stress testing once chest pain resolves
High risk or NSTEMI:
Antithrombotic therapy (ASA, platelet receptor antagonist, anticoagulant)
Reperfusion therapy - immediate, early, delayed or ischemia-guided
Prognosis:
Depends on risk factor management.
ST Elevation Myocardial Infarction
Overview:
Characteristic EKG, symptoms and signs. Intense acute chest pain.
Assessment:
ST elevation, Q-wave development
Elevated cardiac biomarkers
Plan
Hospitalize, emergency
Reperfusion therapy
Primary PCI > fibrinolysis
Aspirin, Platelet receptor antagonist
Prognosis
Short term outcomes depends on time between symptom and revascularization
Degree of cardiac necrosis + complications (arrythmia, heart failure, shock, hypotension, mechanical complications, aneurysm, pericarditis)