Patterson: Case Studies Flashcards
What is CAD and its underlying mechanism?
CAD is coronary artery disease; luminal narrowing of the coronary arteries due to plaque formation
What factors increase the risk for CAD in patients?
Smoking hypertension hyperlipidemia diabetes older age inactivity
What is the prevalence of CAD in the US?
affects 82 million Americans and causes 33% of all deaths in the US
T/F: Total healthcare inpatient cost for CAD is $72 billion or 1/4 of all healthcare costs
True
What is the average age of onset of CAD for women? For men?
72; 62
Which ethnic groups have the highest rates of CAD?
blacks > whites > hispanic/latino
18% of men and 23% of women 40 years and older will die within the first year after a heart attack. 33% and 43% will die within the first 5 years.
(blank) to prevention strategies can help reduce the rates.
adherence
deposits of lipids, macrophages, calcifications in arteries leading to plaque formation
atherosclerosis
What causes coronary artery disease?
arteriosclerosis and atherosclerosis
formation of plaques +/- stenosis of the lumen
can be stable (asymptomatic/angina) or unstable (acute coronary syndrome)
What is an atheroma?
a plug of macrophages, lipids, and fibrous connective tissue
What increases risk for plaque development in arteries?
Elevated plasma levels of low-density lipoprotein cholesterol (LDL-C)
Low plasma levels of high-density lipoprotein cholesterol (HDL-C)
Hypertension
Cigarette smoking
Diabetes mellitus
Age greater than 65 **
Male gender
Family history * - first degree relatives - males aged 55 or less, women 65 or less
Obesity / overweight
Sedentary life style
What is the greatest risk factor for plaque development in arteries?
age
**If you are over the age of 70% your risk is above 20% no matter what
What can be used to calculate the risk of developing heart disease w/i the next 10 years?
Framingham risk calculator
- *uses age, sex, smoker, systolic blood pressure, total cholesterol, HDL, and treated HTN
- *low risk 20%
T/F: The Framingham risk calculator may overestimate the risk of heart disease in certain populations, or underestimate.
True; despite its faults, it’s still one of the best tools we have to estimate risk
This is another, newer calculator used to estimate risk of developing heart disease
ASCVD
Any group of clinical syndromes consistent with myocardial ischemia (or patients with symptoms suggesting an unstable cardiac condition due to ischemia)
acute coronary syndrome
What are the three main conditions that are included in acute coronary syndrome?
unstable angina
NSTEMI
STEMI
What is ACS usually secondary to?
secondary to a ruptured plaque or erosion of a plaque, which releases thrombogenic materials and can lead to thrombus formation and partial or complete occlusion of the vessel
What is unstable angina? Will you see changes on the ECG? Will biomarkers be elevated?
reversible ischemia which causes sudden onset chest pain when at rest or during minimal activity; may or may not see T wave inversion or ST depression; biomarkers will not be elevated due to lack of necrosis of myocardium
How is a NSTEMI similar to unstable angina? How is it different?
symptoms are indistinguishable;
usu has ECG changes of ST segment DEPRESSION and T wave inversion; biomarkers will be elevated due to myocardial damage
What will you see on an ECG during a STEMI?
ST elevation
Why do we not wait for biomarkers in cases of STEMI?
time is of the essence here! Need to reperfuse the coronary vessels to minimize tissue loss - no time to wait for labs
Why can it be difficult to diagnose ACS?
overlap of non cardiac and cardiac disease symptoms
over-diagnosis due to fear of lawsuits and adverse outcomes
misinterpreting biomarkers or ECG
atypical presentation
When evaluating a patient with chest pain, what are your two main objectives?
- determine the patient’s risk for ACS
2. determine the short term risk for an adverse event
What are some urgent (life threatening) causes of chest pain?
aortic dissection
pulmonary embolism
tension pneumothorax
esophageal rupture
What are some other, more benign causes of chest pain?
pneumonia pleurisy pericarditis myocarditis hypertrophic cardiomyopathy PUD GERD esophageal spasm panic attack
What are 5 high yield questions for determining likelihood of ACS?
- nature of chest pain (PPQRST)
- history of CAD
- gender/sex
- age
- number of traditional risk factors for CAD
Describe the typical chest pain in ACS
heavy/pressure sensation in the sternum or epigastrium
radiates to jaw, neck, throat, back or left arm
lasts 15-20 minutes
not relieved by rest
Describe ATYPICAL chest pain in ACS
sharp/stabbing
pain reproduced by movement or by touch
pain lasts for seconds
pain described as heartburn or burning in nature
What percentage of patients with ACS do not have chest pain as a complaint?
25-30% !!!
These ACS patients are more likely to have pain in their jaw, neck and back than in their chest…
women
These ACS patients will complain less about their chest pain
older patients
Chest pain that radiates to both shoulders increases the likelihood risk of an MI by (blank) fold
7
T/F: Pleuritic chest pain, chest pain reproduced by palpation, sharp or stabbing chest pain, and positional chest pain decrease the likelihood risk of an MI by .3 fold
True
What are some red flags for cardiomyopathy with a STEMI?
S3 pulmonary rales jugular venous distension hepatojugular reflex diminished pulse hypotension
What does ST elevation suggest on an ECG?
irreversible ischemia from coronary occlusion
**need urgent reperfusion
How quickly should you get an ECG after a patient enters the ED with suspected ACS?
within 10 minutes!
Is an ECG necessary for diagnosis of ACS?
well, it can be normal in 20-55% of patients with acute MI so… still do serial ECGs ever 15-30 minutes for pts with likely ACS
Can an ECG help determine the location of the vessel occlusion in ACS?
yes!
Are ST elevation and T wave inversion specific for MI?
no!!
**pericarditis, myocarditis and ventricular aneurysm can cause ST segment elevation
T wave inversion can occur with tricyclic and strokes
In a patient with chest pain, how do you differentiate UA from STEMI?
measure biomarkers!
in NSTEMI, biomarkers will be elevated; in UA, they will not
Are biomarkers necessary to make the diagnosis of STEMI?
no!
This biomarker has high sensitivity and specificity for myocardial damage
Troponins I and T
When are troponins first present in blood? When do they peak? How long do they remain elevated?
2-4 hours; 48 hours; 7-10 days
T/F: Troponins can also be elevated in renal disease, tachycardia, A fib, myocarditis, severe cardiomyopathy, GI bleeds, stoke, etc
True
***PPV for ACS is highest when the patient is older, has hypertension, and troponin > 1ng/mL
This biomarker can be detected w/i 2 hours of an MI; it is undetectable at 72 hours; should be repeated every 6-9 hours in initially negative
CK-MB
Why is myoglobin not terribly useful as a biomarker?
well, its detected w/i the first hour after cardiac injury, but it’s not specific at all
What are some risk prediction models that help estimate risk of UA/NSTEMI mortality for patients with unstable angina and non-ST elevation MI?
TIMI
GRACE model
What kinds of things are included in the TIMI risk prediction model to determine overall risk of adverse outcomes in patients with UA/NSTEMI?
age >65 documented prior coronary artery stenosis 3+ conventional cardiac risk factors aspirin use in previous 7 days 2+ anginal events in the past 24 hours ST depression or elevation >1mm elevated cardiac biomarkers
How do you treat patients with chronic stable angina and non diagnostic biomarkers and ECG?
cardiac stress test
teach/encourage the pt to modify their risk factors
T/F: There are lower rates of adherence to guidelines for treatment of UA/NSTEMI in low risk patients, women, elderly patients, and those of certain race/ethnicity
True
How to treat UA/NSTEMI?
bed rest continuous cadiac monitoring (tele) relief of ischemia using nitroglycerin (vasodilator), beta blockers (decrease HR and O2 demand of cardiocytes) antithrombotics? anticoagulants?
This is one invasive treatment for UA/NSTEMI
coronary angiography with potential revascularization
How to treat a STEMI?
urgent treatment via restoration of blood flow (use fibrinolytics, heparins, percutaneous coronary intervention, or coronary artery bypass grafting)!! **1/3 of these patients die within the first 24hrs of ischemia
Prevention measures for ACS?
aspirin beta blockers, BP control stop smoking manage cholesterol diet diabetes control exercise
Promote (blank) in patients with coronary artery disease
prevention
Obtain (blank) immediately in patients suspected to have ACS
ECG
Measure (blank) in all patients suspected to have ACS
troponin
