Balloon Dilatation Catheters

Question 1

What are the three primary uses of balloon dilatation catheters?

Answer 1

Plain Old Balloon Angioplasty (POBA)

Pre-dilatation

Post-dilatation

Question 2

What are the long term downsides to POBA?

Answer 2

Restenosis

Question 3

Name the characteristics of frontline balloons

Answer 3

Primarily used for pre-dilatation

Soft, flexible, deliverable

Expands as pressure increases

Question 4

Name the characteristics of high pressure balloons

Answer 4

Primarily used for post-dilatation, but also at times used for pre-dilatation

Broad/versatile working range

Historically stiffer, less deliverable

Limited growth with pressure increase

Question 5

What it means when we say Nominal pressure?

Answer 5

Pressure at which balloon reaches its stated size

Question 6

What it means when we say Quarter-size?

Answer 6

Pressure at which balloon will reach 0.25 mm larger than stated size above nominal pressure

Question 7

What it means when we say Rated burst pressure

Answer 7

Pressure at which 99.9% of balloons will not rupture with 95% confidence

Question 8

What are the 2 catheter platforms of balloon?

Answer 8

Over the wire (OTW)

Rapid Exchange (RX)

Question 9

What is Important While Getting To The Lesion

Answer 9

Deliverability and Cross

Question 10

What Is Important Once The Lesion Is Crossed

Answer 10

Visibility and Precise, Focal Dilatation

Question 11

What we want when we say Visualization

Answer 11

Ability to see the markers under fluoro

Used to determine the length of the lesion and accurate BDC placement

Question 12

What we want when we say Focal Dilatation

Answer 12

The ability to minimize injury outside the treatment area

Accurate marker placement and abrupt tapers are critical

Stay true to stated size

Question 13

What we want when we say Re-cross

Answer 13

The ability of a BDC to re-cross a lesion or stent

Optimal refold, soft balloon material, and a soft tip all influence re-cross

Question 14

What is POBA used for?

Answer 14

13% of all PCI

Small vessels, bifurcation side-branch, in-stent restenosis

Patients with high bleeding risk or who cannot tolerate dual antiplatelet therapy

Question 15

Name the goals and reasons for predilation

Answer 15

Evaluate lesion prior to stent implantation

Prepare the lesion

Facilitate device (stent) delivery

Reduce plaque shift

Facilitate excellent stent expansion and apposition

Question 16

Name the potential advantages of predilation

Answer 16

Lesion evaluation / preparation prior to stent implantation
–
Increased device delivery success
–
Maintain integrity of drug coating
–
Greater potential for procedural success
–
Decreased complications and lumen loss related to inadequate stent expansion and apposition

Question 17

Name the device selection considerations

Answer 17

Profile:
Initial crossing

Tip design:
Flexible tip, tapered design

Deliverability:
Flexible balloon material, flexible markers

Compliance:
Stretch, pressure applied

Balloon Tapers:
Short tapers to minimize vessel injury

Economic Factors:
Cost

Procedure / fluoro time

Question 18

Whats the goal of post dilation?

Answer 18

Full stent expansion
–
Complete apposition

Question 19

What are the potential advantages of Post dilatation?

Answer 19

More complete stent apposition
–
Restenosis reduction
–
Avoidance of thrombosis
–
Decreased rate of target vessel revascularization (TVR)
–
Uniform drug delivery

Question 20

What are the disadvantages of Post dilatation?

Answer 20

Additional vessel injury
–
Peri-procedural infarction

Question 21

What are the lesion considerations when doing post dilatation?

Answer 21

Lesion Type:
Response to device placement
Residual stenosis

Lesion Length:
Complete coverage
Vessel injury beyond stent edges

Lesion Location:
Dissection risk with small or tapered vessels

Question 22

What are the post balloon selection considerations?

Answer 22

Size:
1/4 size larger,
length less than stent

Case specific:
Pressure capabilities

“High pressure” suitability:
Compliance
Concentration of dilating force
Vessel injury

Tip design:
Flexible tip,
Tapered design

Balloon Tapers:
Short, smooth tapers to minimize vessel injury

Question 23

Stent Delivery System (SDS) Consideration Factors

Answer 23

Designed for crossability

Cost savings

Question 24

Stent Delivery System (SDS) Shortcomings

Answer 24

Potentially inadequate stent expansion
–
Semi-compliant vs. non-compliant material
–
Extension beyond stent margins

Question 25

What are the potentials of post-dilatating with a high pressure/non-compliant system

Answer 25

Clinical data supports good stent deployment
–
Greater dilatation force at lower pressures
–
Low growth at high pressures reduces unwanted vessel expansion
–
Less “dog boning” (concentrates force at lesion)
–
Favorable long-term results when full stent expansion and apposition achieved