Lecture 7: ACS Flashcards
ACS
-Acute Cornoary Syndrome
-Acute myocardial ischemia
-Unstable angina, NSTEMI, STEMI
Blockage of heart arteries
the higher the worse
Ischemia patho
-rupture of artherosclerotic plaque
-platelet adherence, aggregation, activation
-fibrin and platelets form clot
=ischemia
ACS epidemiolgy
-median age 68 years
-males more likely
-sometimes ACS is initial presentation of CAD
-70% of ACS hospitalizations are NSTEMI, 30% STEMI
ACS risk factors
-older age
-males
-fam hx
-PAD
-DM
-renal probs
-prior MI
-smoking
Preciptating Factors
-recent exercise
-weather (cold or warm)
-large meal
-fright/anger
-coitus
-walking against wind
-smoking
s/sx of ACS
-retrosternal chest pain
-may radiate to left arm, back, or jaw
-happens AT REST
-NV
-diaphoresis
-SOB
Atypical ACS sx
-elderly, females, DM, impaired renal function, dementia
-epigastric pain
-indigestion
-stabbing/pleuritic pain
-inc dyspnea in absence of chest pain
When to call ambulance
-continuing chest pain
-severe dyspnea
-syncope/presyncope (fainting)
-palpitations
-time is tissue!
Diagnosing ACS
-12 lead ECG within 10 min of arrival at ER for all pt
-troponin measurement
STEMI ECG
-persistent ST elevation
-Q wave changes (often not seen right away, takes some time to develop)
-Q wave permanent unless it goes away if stunned tissue can recover
NSTEMI and UA ECG
-normal ECG
-no ST elevation
-maybe ST depression, transient ST elevation, or T wave inversion
Troponin
-measured immediately at ER
-released from necrotic myocytes into bloodstream
-high sensitivity (quicker read) preferred over conventional
-normal < 14ng/L (high sensitivity) or < 0.05ng/ML (conventional)
-repeat q3-6h for first 12h to see if its rising or falling
-can be elevated by other conditions
Troponin normal values
-<14ng/L for high sensitivity
-<0.05ng/ML for conventional
Unstable angina
-chest pain may occur at rest
-more severe and longer than stable angina
-less ischemia than NSTEMI
-no elevated tropinin
-no ST elevation
NSTEMI
-chest pain at rest
-troponin elevated
-no ST elevation
STEMI
-chest pain at rest
-troponin elevated
-ST elevation
Complications of ACS
-HF
-valvular dysfunction
-arrhythmias
-bradycardia/heart block
-pericarditis
-stoke or LV thrombosis
-cardiogenic shock
-death
Ventricular remodeling
-change in size, shape, and function of LV after ACS
-leads to HF
-activation of renin-angiotensin-aldosterone system
-hemodynamic factors (inc preload and afterload)
-preventing this is important goal of tx
Major Adverse Cardiac Events (MACE)
-often used as compositre endpoint in trials
-Stroke, MI, CV death
