Cardiac Imaging Flashcards
What is the accumulation of lipid-rich materials on the surface of, or within the sub-endothelial layer of muscular arterial vessels.
Atherosclerosis
Considered the sequellae of chronic inflammatory reaction to injury to the blood vessel wall.
What do atheromas contain histologically (3)
Fat
Macrophages
T cells
+ other elements
Advancing atherosclerosis is associated with increasing ____________ content in plaques
Calcium
What would your workup be for a coronary artery disease in asymptomatic patients to determine risk for future coronary artery event? (3)
- Framingham Risk Assessment
- Stress ECG is the first step
- Electron Beam CT (EBCT)
Gender-specific algorithm used to estimate the 10-year cardiovascular risk?
Framingham Risk Assessment
When used in conjunction with Electron Beam CT, the 2 represent a fairly powerful risk assessment matrix
What does the Framingham Risk Assessment mean at each of these levels:
1) low risk (e.g. _____% risk at ___# years)
2) intermediate risk
3) high risk
1) 10% or less CHD risk at 10 years
2) 10-20% risk
3) >/= 20% risk
What is the first step in nearly all scenarios for an asymptomatic patient to determine risk for future coronary artery event
Stress ECG
Pros for Stress ECG
Cheap, available, fast, non-invasive
Cons for Stress ECG
Relatively low sensitivity, many non-diagnostic findings, does not localize ischemia
Aim of Stress ECG
Adequate workload (W/kg, age dependent), at least submaximal heart rate 0.8x(220-age)
What is the submaximal heart rate equation that Stress ECG aims for
0.8x(200-age)
What test can quantify the presence of calcium (even small amounts in small anatomy) in coronary arteries
Electron Beam CT (EBCT)
When used in conjunction with Framingham Risk Assessment, the 2 represent a fairly powerful risk assessment matrix
The result of the EBCT test is a calcium score, the higher the score, the greater the:
Risk for health problems
- Score of 100 is “high risk” depending on age and gender
- Greater than 400 is BAD
What is your workup for coronary artery disease in symptomatic patients (8)
1) plain films FIRST
2) ECG
3) Scintigraphy
4) PET scan
5) Cardiac ultrasound
6) CT angiography
7) Cardiac MRI
8) Conventional angiography
What is the first test if you suspect coronary artery disease in a symptomatic patient
Plain film
Benefits of plain film
Inexpensive
Low radiation burden
Effective at identifying cardiac size, shape, global relationship between heart and lungs
The diagnostic yield for plain films is low, but so is
Cost and radiation burden
The sensitivity and specificity to identify late disease in the chest are relatively _______ in plain film
High
How does plain film do with calcification in the vasculature and pulmonary parenchyma
Moderately sensitive
Plain film has very low sensitivity to most diagnostically and therapeutically significant findings of cardiovascular disease, until
late in the natural history when decompensation of the heart and lungs is occurring
Thallium and Technetium are isotopes of choice for conventional heart _____
Scintigraphy
Areas of tracer uptake are measured — looking for “cold spots” of ischemia or infarction
Scintigraphy is more sensitive than ____
Stress ECG alone
Scintigraphy is valuable with stress testing to identify areas of
Transient ischemia
IV radioactive agent that binds to membranes in cardiac muscle
18 Fludeoxyglucose for PET scan
