Cardio Week 5 - Surgical Treatment Of Patients With CAD

Question 1

Graded exercise test major purposes

Answer 1

• Detect ischemic heart disease under controlled conditions
• Detect exercise-induced arrhythmias
• Evaluate hemodynamics during exercise

Question 2

Alternatives to graded exercise test

Answer 2

• Pharmacologic testing
• Imaging
• Imaging combined with graded exercise test

Question 3

Pharmacologic stress testing - Dipyridamole and Adenosine

Answer 3

Dilate healthy arteries; unhealthy arteries do not due to plaque build up on the inside

Question 4

Pharmacologic Stress Testing - Dobutamine

Answer 4

Increases mVO2 (myocardial O2 consumption)

Question 5

What are radionuclide imaging or Echocardiography used to assess?

Answer 5

For abnormal wall movement indicative of ischemia

Question 6

Echocardiography

Answer 6

• Ultrasonographic imaging of the heart
• Noninvasive, real-time imaging of valve function and dimensions of the heart
• Color Doppler used to measure flow velocity and direction
• Used to detect heart motion and estimate SV and EF

Question 7

What do echocardiography’s rule in/out?

Answer 7

• Pericardial effusion
• Cardiac tamponade
• Cardiomyopathy
• Masses in/on heart

Question 8

Transesophageal Echocardiography (TEE)

Answer 8

Better image than ordinary echo due to fewer structures to obscure image

Question 9

Imaging Techniques

Answer 9

• Rapid computed tomography to view early calcification of the coronary vessels
• Graded exercise test combined with radionuclide perfusion (SPECT or PET scan)

Question 10

Thallium 201 - What are images examined for cold spots indicative of?

Answer 10

• Ischemia if they occur during exercise
• Nonviable myocardium if they occur post-exercise

Question 11

Thallium 201

Answer 11

• Injection of thallium 201 or other radionuclides
• Taken up by metabolically active myocytes in proportion to blood flow
• Images examined for cold spots - places where the blood flow is less

Question 12

Angiogram

Answer 12

When a dye is injected into the blood vessel and X-rays are used to determine blood flow in the coronary arteries

Question 13

Ventriculography

Answer 13

• Performed during cardiac catheterization (determine cardiac function)
• Check for valvular dz and ventricular dysfunction

Question 14

What estimates does the ventriculography make?

Answer 14

• Cardiac output
• Stroke volume
• Ejection fraction
• Chamber pressures
• Presence of stenosis or regurgitation

Question 15

Multigated acquisition imaging (MUGA)

Answer 15

• Provides views throughout the cardiac cycle
• Calculate LV EF
• Measure emptying of LV with time
• Noninvasive

Question 16

CABG - Coronary artery bypass graft

Answer 16

• Creation of bypasses around the narrowed areas using grafts
• Vein segments are sewn into (grafted) above and below the occluded areas

Question 17

What veins are harvested during a CABG?

Answer 17

• Portions of one or both saphenous veins
• Depending on the quality of the vein and the number of bypasses required

Question 18

Short term consequences of CABG Saphenous VG

Answer 18

• Risk of infection in both the chest and LEs - length of procedure and hematoma formation
• LE wounds can extend from ankle to groin bilaterally
• May be unwilling to move the involved LE due to pain and inflammation

Question 19

Alternatives to saphenous vein graft

Answer 19

• Radial artery
• Internal mammary arteries (left)

Question 20

LIMA to LAD

Answer 20

• Left internal mammary artery grafted to the LAD distal to occlusion
• RIMA may be used on occasion by some surgeons
• Use of IMAs may compromise sternal integrity

Question 21

Minimally - Invasive Direct Coronary Artery Bypass (MIDCAB)

Answer 21

• Alternative to open CABG for some patients
• Much smaller incision
• Endoscopic surgery

Question 22

Advantages of Percutaneous Coronary Intervention (PCI)

Answer 22

• Can combine diagnostic testing with intervention
• More rapid intervention than CABG and is less invasive

Question 23

Disadvantage to percutaneous coronary intervention (PCI) or PTCA

Answer 23

• Long-term results are not as good as CABG
• May not work, requiring CABG after PCI is done

Question 24

Percutaneous Coronary Intervention (PCI) or PTCA

Answer 24

Balloon-tipped catheter is inserted into the occluded vessel and inflated to restore patency of vessel by compressing the plaque and widening the lumen

Question 25

Stent

Answer 25

• Wire device placed with balloon-tipped catheter
• Opened within the occluded vessel to maintain patency
• May be coated with material to reduce risk of re-occlusion

Question 26

Cardiac diagnostic testing

Answer 26

• Heart rate and rhythm
• Evidence of CAD

Question 27

Revascularization procedures

Answer 27

• CABG with SVG
• Radial artery
• LMA to LAD
• PCI

Question 28

Ischemia/Reversible injury

Answer 28

Blood flow returns when the patient goes back to resting

Question 29

Emergency management

Answer 29

• Receives a dose of TPA through a catheter
• Stabilized and sent for cardiac catheterization to determine what vessels are compromised and to what extent

Question 30

What tests would you use to visualize metabolism of the heart?

Answer 30

• SPECT (single photon emission CT) or PET (positron emission tomography) scan
• Echocardiogram

Question 31

SPECT or PET

Answer 31

• Provide 3D imaging
• Can use single photon or positron emission computed tomography
• Gamma ray detection
• Myocardial perfusion imaging
• May use Tc99 rather than Thallium
• Can calculate the L ventricular ejection fraction

Question 32

Bed rest and bleeding risk

Answer 32

• Three hours to prevent bleeding and hematoma formation at the groin due to vascular access required for cardiac catheterization
• When pacing wires for temporary pacemaker are removed from chest