CCI Invasive Catheterization Procedures 3 — Questions and Answers
Question 1: What is the significance of a 'damping' waveform observed when a catheter is positioned in the coronary ostium?
- It indicates optimal catheter engagement for injection
- It suggests catheter tip occlusion of the ostium, risking ischemia or dissection (Correct answer)
- It is a normal finding during selective coronary angiography
- It indicates the catheter is too proximal and not engaged
Correct answer: It suggests catheter tip occlusion of the ostium, risking ischemia or dissection
A damped waveform indicates the catheter tip is obstructing coronary flow, which can cause ischemia, ventricular fibrillation, or ostial dissection if not corrected immediately.
Question 2: Which of the following correctly describes the transpulmonary gradient (TPG)?
- Mean PAP minus mean PCWP (Correct answer)
- Systolic PAP minus diastolic PAP
- Mean RAP minus mean PAP
- Mean PCWP minus mean RAP
Correct answer: Mean PAP minus mean PCWP
The transpulmonary gradient equals mean pulmonary artery pressure minus mean pulmonary capillary wedge pressure, reflecting resistance across the pulmonary vascular bed.
Question 3: A patient undergoing diagnostic catheterization has an oxygen saturation step-up of 8% between the right atrium and right ventricle. What diagnosis should be suspected?
- Pulmonary arteriovenous malformation
- Ventricular septal defect (VSD) (Correct answer)
- Atrial septal defect (ASD)
- Patent ductus arteriosus (PDA)
Correct answer: Ventricular septal defect (VSD)
An oxygen saturation step-up at the RV level (≥5%) indicates a left-to-right shunt at the ventricular level, consistent with a VSD.
Question 4: What is the purpose of using a long sheath during radial artery access for coronary angiography?
- To allow larger guide catheters to be used
- To reduce radial artery spasm and facilitate catheter exchanges (Correct answer)
- To measure central aortic pressure more accurately
- To enable balloon pump insertion through the radial artery
Correct answer: To reduce radial artery spasm and facilitate catheter exchanges
A long radial sheath reduces friction during catheter exchanges and minimizes radial artery spasm caused by repeated catheter manipulation.
Question 5: Which complication is uniquely associated with the transradial approach compared to the transfemoral approach?
- Retroperitoneal hemorrhage
- Radial artery occlusion (Correct answer)
- Aortic dissection
- Femoral neuropathy
Correct answer: Radial artery occlusion
Radial artery occlusion is a complication specific to transradial access, occurring in approximately 1–5% of cases, though it is usually asymptomatic due to dual hand circulation.
Question 6: A patient's cardiac output measured by thermodilution is 3.2 L/min with a body surface area of 1.8 m². What is the cardiac index?
- 1.6 L/min/m²
- 1.78 L/min/m² (Correct answer)
- 5.76 L/min/m²
- 2.8 L/min/m²
Correct answer: 1.78 L/min/m²
Cardiac index equals cardiac output divided by BSA: 3.2 ÷ 1.8 = 1.78 L/min/m², which is below the normal range of 2.2–4.0 L/min/m².
Question 7: During ventriculography, which projection best demonstrates the posterobasal wall of the left ventricle?
- 30° RAO projection
- 60° LAO projection with cranial angulation
- 45° LAO projection (Correct answer)
- AP projection with caudal angulation
Correct answer: 45° LAO projection
The 45–60° LAO projection separates the LV into septal and lateral walls and is the best view to assess the posterobasal (inferior) wall of the left ventricle.
CCI Invasive Catheterization Procedures 3
What is the significance of a 'damping' waveform observed when a catheter is positioned in the coronary ostium?