Cardiac Surgery Certification Exam Aortic Surgery and Mechanical Circulatory Support 1 — Questions and Answers
Question 1: The DeBakey classification of aortic dissection Type I involves:
- Dissection originating in the ascending aorta and extending into the descending aorta (Correct answer)
- Dissection confined to the ascending aorta only
- Dissection confined to the descending aorta
- Dissection involving only the aortic arch
Correct answer: Dissection originating in the ascending aorta and extending into the descending aorta
DeBakey Type I dissection begins in the ascending aorta and propagates distally through the arch and into the descending aorta, requiring emergency surgery.
Question 2: Stanford Type A aortic dissection requires emergency surgery primarily because of the risk of:
- Pericardial tamponade, aortic regurgitation, and coronary ostial involvement (Correct answer)
- Renal ischemia alone
- Lower limb malperfusion
- Descending aorta rupture
Correct answer: Pericardial tamponade, aortic regurgitation, and coronary ostial involvement
Type A dissection threatens the proximal aorta, risking rupture into the pericardium (tamponade), aortic valve disruption, and coronary ostial dissection causing acute MI.
Question 3: Deep hypothermic circulatory arrest (DHCA) is used in aortic arch surgery primarily to:
- Provide a bloodless operative field while protecting the brain and organs during circulatory pause (Correct answer)
- Allow higher pump flow rates
- Prevent coagulopathy
- Enable off-pump arch reconstruction
Correct answer: Provide a bloodless operative field while protecting the brain and organs during circulatory pause
DHCA cools the patient to 15–20°C, dramatically reducing cerebral metabolic demand and allowing safe cessation of circulation for arch reconstruction.
Question 4: Which technique can extend the safe duration of circulatory arrest during aortic arch surgery beyond DHCA alone?
- Selective antegrade cerebral perfusion (SACP) (Correct answer)
- Retrograde cardioplegia
- Increased heparin dosing
- Higher pump flow before arrest
Correct answer: Selective antegrade cerebral perfusion (SACP)
SACP delivers oxygenated blood directly into the cerebral vessels during circulatory arrest, extending safe arch reconstruction time beyond the limits of DHCA alone.
Question 5: The Bentall procedure is performed for:
- Aortic root aneurysm with aortic regurgitation, replacing the root, valve, and reimplanting coronary buttons (Correct answer)
- Isolated aortic valve stenosis
- Descending aorta aneurysm repair
- Mitral valve replacement combined with aortic grafting
Correct answer: Aortic root aneurysm with aortic regurgitation, replacing the root, valve, and reimplanting coronary buttons
The Bentall procedure replaces the aortic root with a composite graft (valve + ascending aorta), with reimplantation of the coronary ostia as buttons into the graft.
Question 6: An intra-aortic balloon pump (IABP) improves cardiac function by:
- Inflating in diastole to augment coronary perfusion and deflating before systole to reduce afterload (Correct answer)
- Providing continuous flow bypass of the left ventricle
- Pacing the ventricle during diastole
- Increasing heart rate to improve cardiac output
Correct answer: Inflating in diastole to augment coronary perfusion and deflating before systole to reduce afterload
IABP counterpulsation inflates during diastole (augmenting coronary perfusion) and deflates just before systole (reducing LV afterload via aortic unloading).
Cardiac Surgery Certification Exam Aortic Surgery and Mechanical Circulatory Support 1
The DeBakey classification of aortic dissection Type I involves: