Tools of the Trade: Cardiac Testing

Question 1

Characteristics of CXR

Answer 1

Tissue decreases radiation
penetration to film
• Tissue=white
• air=black
• Standard CXR views:
– PA (Posterior-Anterior)
– Lateral

Question 2

Characteristics of Echocardiogram

Answer 2

• Ultrasound sent into body, strikes
objects and returns to transducer
• Returned ultrasound can be
transformed into:
– 2-Dimensional motion picture
– M-Mode
– Color Doppler map of blood flow
– Spectral Doppler map of blood or tissue
velocity

Question 3

Information that may be obtain from Echo (11)

Answer 3

• Chamber size
• Function
• Chamber structure
• Wall motion
• Valves
• Pressure and
hemodynamics
• Shunts
• Murmurs
• Intracardiac
masses
• Bacterial
endocarditis
• Pericardial disease

Question 4

General concepts of stress testing

Answer 4

• Precipitate ischemia by increasing
myocardial oxygen demand (stress)
• Identify ischemia by changes in:
– blood pressure
– ECG
– symptoms
– blood flow (perfusion) imaging
– wall motion (echocardiography) imaging

Question 5

Major types of stress testing

Answer 5

• Exercise treadmill test (ETT)
• Imaging stress tests
– Echocardiography
– Radionuclide (nuclear)

Question 6

Indications for exercise treadmill test (ETT) (5)

Answer 6

• screening for CAD
• evaluate chest pain
• determine exercise capacity
• evaluate prognosis
• evaluation after revascularization

Question 7

Contraindications for ETT

Answer 7

• **BAD or POORLY CONTROLLED Heart Disease
• unstable angina
• untreated unstable arrhythmias
• uncompensated HF
• advanced AV block
• acute myo/pericarditis
• critical aortic stenosis
• uncontrolled HTN
• significant HOCM
• acute systemic illness

Question 8

“best” ETTs for identifying CAD

Answer 8

• left main –> 3 vessel CAD

- LAD> RCA > CIRC –> 1 vessel CAD

Question 9

Types of imaging stress tests

Answer 9

• stress w/radionuclide or echo monitoring
• exercise
• pharmacologic: w/vasodilator or dobuatamine

Question 10

Indications for imaging stress test

Answer 10

• abnormal baseline ECG, digoxin, Wolf-Parkinson-White
• increased sensitivity of test
• localization
• preoperative risk assessment
• evaluate myocardial viability

Question 11

Characteristics of radionuclide perfusion imaging

Answer 11

• Tracer deposited based on blood flow
• Imbalance between supply and demand
results in relative decreased perfusion
• Compare perfusion during increased
demand (stress) and decreased demand
(rest)
• Reversible perfusion defects indicate
reversible ischemia
• Fixed perfusion defects indicate
infarction, scar

Question 12

Main radionuclide perfusion imaging agents

Answer 12

• Thallium-201
– Potassium analog
– Continuous exchange across cell membrane
• Technetium-99m-Sestamibi (Cardiolite)
– Lipophilic monovalent cation
– Biliary clearance
– One pass

Question 13

Characteristics of MRI

Answer 13

• Strong magnetic field
• 3D, tomographic images
• No ionizing radiation
• Anatomic imaging (spin echo)
• Functional imaging (cine CMRI)

Question 14

Contraindications of MRI

Answer 14

– Metallic implants
– Kidney dysfunction for Gadolinium
contrast

Question 15

Information that can be assessed via coronary angiography (8)

Answer 15

• patency of surgical bypass grafts
• aortic pathology (dissection)
• myo/pericardial disease
• cardiac masses
• mediastinal pathology
• pulmonary vein assessment (EP)
• congenital heart disease
• coronary atherosclerosis

Question 16

Characteristics of coronary angiography

Answer 16

• Catheter inserted into artery or vein,
advanced to heart or coronary
arteries
• Measurements of:
– pressure
– gradients
– saturation
– intracardiac shunt
• Inject contrast for angiography