Cardiac Surgery Certification Exam Cardiac Valve Surgery 2 — Questions and Answers
Question 1: Which hemodynamic finding is characteristic of severe aortic stenosis requiring surgical intervention?
- Mean aortic valve gradient greater than 40 mmHg with valve area less than 1.0 cm² (Correct answer)
- Mean gradient less than 20 mmHg with preserved ejection fraction
- Aortic valve area greater than 1.5 cm²
- Pulmonary capillary wedge pressure below 10 mmHg
Correct answer: Mean aortic valve gradient greater than 40 mmHg with valve area less than 1.0 cm²
Severe AS is defined by a mean gradient >40 mmHg and aortic valve area <1.0 cm², indicating the need for intervention.
Question 2: The Ross procedure involves:
- Transferring the patient's own pulmonary valve to the aortic position with a homograft in the pulmonary position (Correct answer)
- Replacing the aortic valve with a bovine pericardial bioprosthesis
- Repairing the aortic valve leaflets using autologous pericardium
- Implanting a transcatheter aortic valve via the femoral artery
Correct answer: Transferring the patient's own pulmonary valve to the aortic position with a homograft in the pulmonary position
The Ross procedure replaces the aortic valve with the patient's own pulmonary valve (autograft) and reconstructs the right ventricular outflow with a homograft, providing a living autograft without anticoagulation.
Question 3: The most critical technical step when implanting a mechanical aortic prosthesis to avoid complications is:
- Secure seating of the sewing ring without paravalvular gaps (Correct answer)
- Choosing the largest possible prosthesis size
- Avoiding cardioplegia during the procedure
- Minimizing cross-clamp time regardless of technique
Correct answer: Secure seating of the sewing ring without paravalvular gaps
Ensuring complete annular seating without paravalvular gaps prevents paravalvular leak, which can cause hemolysis, heart failure, and need for reoperation.
Question 4: Patient-prosthesis mismatch (PPM) after aortic valve replacement is defined as an effective orifice area index of:
- Less than 0.85 cm²/m² (Correct answer)
- Greater than 1.2 cm²/m²
- Less than 1.5 cm²/m²
- Greater than 2.0 cm²/m²
Correct answer: Less than 0.85 cm²/m²
PPM occurs when the effective orifice area index is <0.85 cm²/m², meaning the implanted prosthesis is too small for the patient's body surface area, causing residual obstruction.
Question 5: Which surgical technique can be used to implant a larger aortic prosthesis in patients with a small aortic root?
- Aortic root enlargement (Nicks or Manouguian procedure) (Correct answer)
- Sutureless valve implantation
- Mechanical valve downsizing
- Pulmonary autograft (Ross) only
Correct answer: Aortic root enlargement (Nicks or Manouguian procedure)
Root enlargement procedures like Nicks (extending into the anterior mitral leaflet) or Manouguian (into the aorto-mitral curtain) allow placement of a larger prosthesis.
Question 6: Which complication of aortic valve replacement requires emergency reoperation and presents with severe new aortic regurgitation immediately post-bypass?
- Prosthetic valve malposition or paravalvular leak (Correct answer)
- Atrial fibrillation
- Sternal wound dehiscence
- Pericardial effusion
Correct answer: Prosthetic valve malposition or paravalvular leak
Significant paravalvular leak or prosthetic malposition producing severe acute aortic regurgitation after bypass requires immediate return to CPB for revision.
Cardiac Surgery Certification Exam Cardiac Valve Surgery 2
Which hemodynamic finding is characteristic of severe aortic stenosis requiring surgical intervention?