Cardiac Surgery Certification Exam Aortic Surgery and Mechanical Circulatory Support 2 — Questions and Answers
Question 1: The primary indication for the Impella device in cardiac surgery patients is:
- Mechanical support for cardiogenic shock or high-risk procedures requiring LV unloading (Correct answer)
- Temporary pacing
- Treatment of aortic stenosis
- Prevention of atrial fibrillation
Correct answer: Mechanical support for cardiogenic shock or high-risk procedures requiring LV unloading
The Impella is an axial flow pump placed across the aortic valve to actively unload the LV and provide hemodynamic support in cardiogenic shock or high-risk interventions.
Question 2: Extracorporeal membrane oxygenation (ECMO) in adult cardiac surgery is used primarily as:
- Rescue therapy for refractory cardiogenic shock or cardiac arrest unresponsive to conventional support (Correct answer)
- Routine postoperative monitoring
- Primary bypass during elective CABG
- Long-term destination therapy
Correct answer: Rescue therapy for refractory cardiogenic shock or cardiac arrest unresponsive to conventional support
VA-ECMO provides both cardiac and respiratory support as a bridge to recovery or decision in patients with refractory cardiogenic shock after cardiac surgery.
Question 3: The most important complication to monitor for in patients on veno-arterial ECMO after cardiac surgery is:
- Limb ischemia from the femoral arterial cannula and left ventricular distension (Correct answer)
- Hypertension
- Hyperkalemia alone
- Atrial septal defect
Correct answer: Limb ischemia from the femoral arterial cannula and left ventricular distension
Femoral arterial cannulation can cause distal limb ischemia, and the ECMO circuit's retrograde flow can distend the non-ejecting LV, both requiring active monitoring.
Question 4: Which finding on chest X-ray after cardiac surgery suggests tension pneumothorax requiring immediate decompression?
- Tracheal deviation away from the affected side with absent lung markings and hemodynamic instability (Correct answer)
- Small pleural effusion on the left
- Widened mediastinum
- Elevated left hemidiaphragm
Correct answer: Tracheal deviation away from the affected side with absent lung markings and hemodynamic instability
Tension pneumothorax causes tracheal deviation away from the collapsed lung, absent breath sounds, and cardiovascular collapse requiring immediate needle decompression.
Question 5: The diameter threshold that generally triggers surgery for an ascending aortic aneurysm in a patient with a bicuspid aortic valve is:
- 5.5 cm (or 5.0 cm with additional risk factors) (Correct answer)
- 7.0 cm
- 4.0 cm
- 6.5 cm
Correct answer: 5.5 cm (or 5.0 cm with additional risk factors)
Current guidelines recommend surgery for bicuspid aortic valve-associated ascending aneurysms at 5.5 cm, or at 5.0 cm when risk factors such as rapid growth or family history are present.
Question 6: The 'elephant trunk' technique in staged total aortic replacement is performed to:
- Leave a free-floating graft segment in the descending aorta to facilitate the second-stage repair (Correct answer)
- Repair the descending aorta in a single stage
- Bypass the coronary arteries during arch replacement
- Enable percutaneous completion of the arch repair
Correct answer: Leave a free-floating graft segment in the descending aorta to facilitate the second-stage repair
The elephant trunk leaves a graft tail hanging in the descending aorta after Stage 1 arch repair, providing a landing zone for Stage 2 descending aortic repair.
Cardiac Surgery Certification Exam Aortic Surgery and Mechanical Circulatory Support 2
The primary indication for the Impella device in cardiac surgery patients is: