Dr. Rogers ACS Part 1 Flashcards
Types of acute coronary syndrome
-Silent ischemia
-Stable ischemic heart disease
-Unstable angina
-Non-ST elevation myocardial infarction
-ST elevation myocardial infarction
Epidemiology of ACS
-Median age at ACS presentation is 68 years
-Males are more likely to have ACS
-For some patients, ACS is initial presentation of CAD
-In the United States, >780,000 persons per year will experience and ACS
Risk factors for ACS
-Diet
-Age
-Smoking
-Obesity
-Genetics
-Male
-Diabetes
-Renal insufficiency
-Presence of peripheral
Precipitating factors for ACS
-Cold
-Wind
-Walking upstairs
-Recent diet
-Sexual intercourse
-Emotions
Signs and symptoms of ACS
-Retrosternal chest pain
-Nausea or vomiting
-Diaphoresis
-Shortness of breath
Atypical symptoms of ACS
-Epigastric pain
-Indigestion
-Stabbing or pleuritic pain
-Increasing dyspnea in the absence of chest pain
What kind of patients are more likely to experience atypical symptoms?
-Elderly
-Females
-Diabetics
-Impaired renal function
-Dementia
When should a patient be sent to the hospital?
-Continuing chest pain
-Severe dyspnea
-Syncope/presyncope
-Palpitations
How do you diagnose ACS?
All patients with acute chest pain should have an ECG within 10 minutes of arrival at an emergency facility and should have troponin measured as soon as possible after presentation
Q wave changes in STEMI
-Often not present on initial ECG, but develops over hours to days
-Electrical hole - scar tissue cannot conduct electricity
-May disappear after early reperfusion if stunned tissue can recover
-Often remain permanently
Typical ECG in a patient with NSTEMI or UA
-May have normal ECG
-ST depression, transient ST-elevation, or new T-wave inversion are possible
-Q wave changes unlikely
-No ST elevation
Why do we prefer high sensitivity troponin?
-Greater sensitivity and negative predictive values
-Shorter time from onset of chest pain to a detectable concentration
Normal values of troponin
-High sensitivity: <14 ng/L
-Conventional: <0.05 ng/mL
How often should troponin levels be measured?
-3 levels over 12 hours
-Initial may be negative
Acute myocardial injury biomarkers
-Tachyarrhythmia
-Hypotension or hypertension
-Cardiac trauma
-Acute HF
-Myocarditis and pericarditis
-Pulmonary embolism
-Sepsis
-Burns
-Respiratory failure
-Acute neurological diseases
-Drug toxicity
Chronic myocardial injury biomarkers
-LV hypertrophy or ventricular dilation
-Renal insufficiency
Clinical presentation of stable angina
Chest pain that occurs during physical exertion that is predictable, relieved by rest, and lasts a short time
Clinical presentation of unstable angina
-Chest pain may occur at rest, while sleeping, or with little physical exertion
-Comes as a surprise
-Is more severe and lasts longer than stable angina
Difference between unstable angina and NSTEMI/STEMI
-Unstable angina has less ischemia and does not lead to detectable quantities of troponin
-NSTEMI/STEMI has elevated troponin
Difference between NSTEMI and STEMI
-NSTEMI has no ST elevation on ECG (may have ST depression or T wave inversion)
-STEMI has persistent ST elevation of ECG
Complications of ACS
-Heart failure
-Valvular dysfunction
-Arrhythmias
-Bradycardia/heart block
-Pericarditis
-Stroke secondary to LV thrombus
-Cardiogenic shock
-Death
What is ventricular remodeling?
-Changes in the size, shape and function of the left ventricle after an ACS
-Leads to heart failure
Which factors are involved in ventricular remodeling?
-Activation of the renin-angiotensin-aldosterone system
-Hemodynamic factors (increased preload and afterload)
What are major adverse cardiac events (MACE)?
Usually includes stroke, MI, and cardiovascular death
