CIR CIR Equipment Technology & Device Management 1 — Questions and Answers
Question 1: What is the primary purpose of a hydrophilic coating on an interventional guidewire?
- To increase wire visibility under fluoroscopy
- To reduce friction and improve trackability through tortuous vessels (Correct answer)
- To prevent thrombus formation on the wire surface
- To increase wire stiffness for better support
Correct answer: To reduce friction and improve trackability through tortuous vessels
Hydrophilic coatings reduce surface friction when wet, allowing guidewires to navigate through tortuous or occluded vessels with greater ease.
Question 2: Which catheter design feature is most important for delivering a coronary stent to a distal lesion?
- Large inner diameter lumen
- High pushability and low crossing profile (Correct answer)
- Thermoplastic body construction
- Braided stainless steel shaft
Correct answer: High pushability and low crossing profile
A low crossing profile allows the stent delivery catheter to pass through tight stenoses, while high pushability ensures the device can be advanced to distal target sites.
Question 3: What does the French (Fr) size designation indicate about an interventional catheter or sheath?
- The outer diameter in millimeters divided by π
- The inner diameter in millimeters
- The outer diameter in millimeters multiplied by 3 (Correct answer)
- The catheter length in centimeters
Correct answer: The outer diameter in millimeters multiplied by 3
The French size equals three times the outer diameter in millimeters (1 Fr = 0.333 mm OD), so a 6 Fr sheath has an outer diameter of approximately 2 mm.
Question 4: When selecting a balloon catheter for coronary angioplasty, which parameter determines the maximum pressure the balloon can withstand before rupturing?
- Nominal pressure
- Rated burst pressure (RBP) (Correct answer)
- Compliance rating
- Inflation volume
Correct answer: Rated burst pressure (RBP)
The rated burst pressure (RBP) is the manufacturer-tested maximum pressure at which 99.9% of balloons will not rupture, guiding safe inflation limits.
Question 5: A non-compliant balloon differs from a semi-compliant balloon primarily in that it:
- Expands significantly beyond its nominal diameter at high pressures
- Maintains a consistent diameter even at high inflation pressures (Correct answer)
- Is used only for peripheral vascular interventions
- Requires a larger guide catheter lumen
Correct answer: Maintains a consistent diameter even at high inflation pressures
Non-compliant balloons resist expansion beyond their nominal diameter at high pressures, making them ideal for stent post-dilation and resistant lesions.
Question 6: Which hemostasis valve on a guide catheter allows instrument exchanges without significant blood loss or air entry?
- Tuohy-Borst adapter
- Y-connector with rotating hemostatic valve (Correct answer)
- Luer-lock stopcock
- Touhy-Borst with side-arm flush
Correct answer: Y-connector with rotating hemostatic valve
The Y-connector with a rotating hemostatic valve seals around guidewires and devices during exchanges while the side port allows continuous flushing.
CIR CIR Equipment Technology & Device Management 1
What is the primary purpose of a hydrophilic coating on an interventional guidewire?