Coronary Balloons in various cardiac interventions

A description of various intra coronary balloons

1. DRUG ELUTING BALLOONS,
PTCA BALLOONS AND OTHER
BALLOONS
DR. SURAJ KASHID

2. Composition of a Balloon
 The first angioplasty balloon made by Gruentzig in
1976 was of polyvinyl chloride (PVC).
The next generation of balloon technology used cross-
linked polyethylene (PE)
PE balloons are as compliant as PVC ,with a higher
rated burst pressure.

3. Polyurethane makes balloon more resistant to damage.
 It produces the most durable balloon for a given
thickness.
Materials used now are polyethylene terephthalate
(PET) or nylon.
PET offers good tensile strength

4. Nylon is not as strong as PET nor as compliant as PE
Nylon is softer, more easily refolded -easier to withdraw
into the guiding catheter or introducer sheath.

5. A standard dilatation balloon consists
cylindrical body
two conical tapers
two necks (proximal and distal).

6. Low pressure balloons
 Low-pressure, elastomeric balloon are made of latex or
silicone that is used primarily in fixation and occlusion.
 Low pressure balloons are molded in a tubular shape
which is then expanded several times its original size
Cannot be inflated to precise dimensions or retain well
defined shapes and high pressures.

7. High-pressure balloons
Non-elastic balloon used to apply force.
High-pressure balloons are molded from noncompliant
or semi-compliant materials that retain their designed
size and shape under high pressure.
Thin-walled and exhibit high tensile strength –used to
enlarge a narrow opening or passage within the body.

8. Balloon catheters used in angioplasty are
Over-the-Wire (OTW)
Rapid Exchange design
Fixed Wire balloon systems.

9. Over-The-Wire (OTW) Balloon
Catheters
Balloon catheters which have two lumens running through the
entire course of balloon catheter.
 One lumen is for passage of guide wire and the other lumen for
connecting with an indeflator for balloon inflation or deflation.

Useful when enhanced trackability is required and also in
procedures requiring multiple guide wire exchanges and balloon
upsizing. 

10. Monorail or Rapid Exchange
(RX) Balloon Catheters
Rapid-exchange (RX) or “monorail” balloon catheters -current
standard for percutaneous coronary interventions
Two lumens
Guide wire lumen does not extend along the entire course of the
balloon. It starts from distal end but finishes before the proximal
end of the balloon catheter.
Advantage -allows a rapid exchange of interventional devices
over the same standard length guide wire

11.  Significant reduction in procedural and fluoroscopy time.
Allow the use of smaller diameter wires, catheters, and stents.
Technical success- similar to over the wire balloons.
Monorail system adds to the safety of percutaneous
interventions-lower doses of contrast medium, shorter duration
of fluoroscopy, and smaller device diameters

12. Fixed Wire-Balloon Systems
Composed of an inelastic balloon wrapped around a smaller
section of a guidewire.
During introduction across a stenosis, the guidewire attached to
the balloon can be rotated freely, but it cannot advance
independently of the balloon.
The wrapped configuration is maintained by means of a
temporary bond.
 Inflation of the balloon, following proper positioning of the
catheter breaks the bond, permitting the balloon to unwrap from
the guidewire

13. Balloon Coating
Variety of coatings can be added to the surface of a balloon to
enhance or change its properties
Balloons may be coated for
lubrication
trackability
abrasion resistance
deliver an antirestenotic drug.

14. TERMS USED IN CONTEXT OF
ANGIOPLASTY BALLOONS
Balloon Diameter: nominal inflated balloon diameter measured at
a specified pressure
Balloon Length: working length or the length of the straight body
section
Nominal Pressure: pressure at which when balloon is inflated it
achieves the listed balloon diameter.  
Mean Burst pressure (MBP):  is the average pressure where 50%
of balloons will burst (measured at body temperature). 
Rated Burst Pressure (RBP): the pressure below which 99.9% of
the balloons will not burst upon single inflation.
Indian Heart J. 2009; 61:178-185

15. Balloon profile:  The maximum diameter of the balloon when
mounted on a catheter in its deflated and wrapped condition or the
smallest hole through which the deflated wrapped balloon can pass. 
Balloon compliance: change in balloon diameter per atmosphere
of inflation pressure.
Index of stretchability of the balloon.
More compliant balloons can over-dilate a vessel- dissection, vessel
rupture, abrupt closure and other ischemic complications.

16. Creep: Tendency of a balloon to enlarge after serial inflations at
the same pressure. (More compliant balloons have more creep.)
Pushability: Pushability refers to the ability to advance the
balloon across the lesion. 
Trackability:  Ease of tracking a balloon over the guidewire up
to the target lesion.

17. BALLOON COMPLIANCE
Balloon compliance -the degree to which a balloon’s diameter
changes as a function of pressure.
A low-compliance, high-pressure balloon might expand only
upto 10% when inflated to the rated pressure while a high-
compliance, high pressure balloon might stretch 15 – 30%.

18. Non Compliant Balloons
High-strength, thin walled balloons, made from PET and used
for coronary and peripheral angioplasty, stent delivery.
Compliance ranges from 0-10% and rated burst pressure ranges
from 18-27 atm.
The rated burst pressure(RBP) can be increased by increasing
thickness of balloon
The non-compliant higher pressure balloons are useful for post
dilatation after stenting. 

19. Semi Compliant Balloons
Standard balloons used for pre-dilatation of lesion
before stent implantation.
Nominal pressure of 6-8 atm. and RBP of 12-18 atm.

20. Compliant Balloons
Low pressure, thin and thick-walled balloons made
from Polyurethane, Nylon .
Used for occlusion and anchoring
Highly compliant with compliance ranging from 20-
100% or more and size ranging from 0.5 to 60 mm in
diameter .
The burst pressures typically range from 0-2 atm.  

21. Quick inflation and deflation times
Conform to complex vasculature, maintaining the
occlusion or moulding as needed.
Types of compliant balloons –
Reliant balloon from Medtronic Inc.
Coda from Cook Inc
Equalizer balloon from Boston Scientific Inc.
Length 65-120 cm, and diameter between 20-46 mm.
 

22. Useful when vessel size is uncertain
Once the lesion is open and nitroglycerin is given, the
vessel may show a larger lumen-second dilation at
higher pressure further expands a compliant balloon

When multiple lesions are targeted in different sized
vessels.

23. Compliance

24. PERFUSION BALLOONS
Perfusion Catheter is indicated for balloon dilatation of the
stenotic portion of a coronary artery or bypass graft stenosis
maintaining myocardial perfusion.
Useful in managing coronary perforations -inflated balloon seals
the perforation while central lumen provides perfusion to distal
bed.

25. Preservation of distal coronary perfusion during
prolonged balloon inflation with an autoperfusion
angioplasty catheter.
Allows for inflations up to 3 min in duration
without producing deleterious changes in the ST
segment or severe reductions in regional
myocardial blood flow.
Z G Turi, C A Campbell, M V Gottimukkala and R A Kloner
Circulation. 1987;75:1273-1280

26. Cathet Cardiovasc Diagn 1994 Apr;31(4):264-9.
Pros and cons of perfusion balloons in failed angioplasty.
The objective of this study was to determine the angiographic outcome of 59
consecutive patients treated with prolonged inflation with perfusion balloons
as the primary treatment for failed angioplasty.
In group of patients with unsuccessful outcome following conventional
balloon angioplasty, success with the perfusion balloon was modest.
Angiographic deterioration was frequently observed following unsuccessful
prolonged inflation. 
Foley JB, Sridhar K, Dawdy J, Konstantinou C, Brown RI, Penn IM

27. BALLOON FOR DRUG
DELIVERY
High-pressure balloons are very useful in several different
applications used for drug delivery.
Delivers the medication at the local site
The ClearWay OTW drug delivery balloon is a micro-porous
PTFE(polytetrafluoroethylene) balloon catheter intended for
the local delivery of various therapeutic and diagnostic agents.

28. ClearWay is a semi-compliant low pressure balloon.
ClearWay OTW has the ability to optimize site specific drug
delivery.
Mechanism of action- 
occludes flow
contains the thrombus
allows for selective local infusion of drug. 

29. The ClearWay OTW drug delivery balloon provides up
to 500 times the drug concentration compared to IV
drug delivery at the point of delivery without increasing
systemic load
 The ClearWay OTW is an over-the-wire .035”
guidewire compatible platform.

31. DRUG ELUTING BALLOON
The concept -delivering a rapid release of drug into the arterial
tissue is more effective than the gradual release of drugs.
New option to treat patients in whom stent implantation is not
desirable - small vessels, in-stent restenosis, bifurcation side-
branch, and acute ST-elevation MI.

32. Currently DEBs available are
 B Braun’s SeQuent Please
Medrad Interventional’s Cotavance
Eurocor’s  DIOR™ paclitaxel-coated
Invatec’s  IN.PACT Amphirion: paclitaxel-eluting balloon for
peripheral use.

33. CUTTING BALLOON
Reduces vessel stretch and vessel injury by scoring the
vessel longitudinally
The device delivers a controlled fault line during
dilatation to ensure crack propagation in an orderly
fashion.
Balloon inflation is at lower inflation pressures (4-8
atmospheres).
The reduced inflation pressure causes less injury to the
target vessel -decrease neoproliferative response -less
in-stent restenosis. 

34. Cutting balloon (Boston Scientific Inc.) has three or four
atherotomes (microsurgical blades), which are 3-5 times sharper
than conventional surgical blades.
The blades fixed longitudinally on the outer surface of a non-
complaint balloon, expand radially and deliver longitudinal
incisions in the plaque
Balloon sizes of 2.00-3.25 mm are provided with 3 atherotomes

35. AngioSculpt
The AngioSculpt Scoring Balloon Catheter (Abbott Vascular) -
modification of cutting balloon technique.
 It has a flexible nitinol scoring element with three rectangular
spiral struts which work in tandem with a semi-compliant
balloon to score the target lesion.
Low crossing profile.

36. AngioSculpt

37. BALLOON RUPTURE
Circumferential Rupture:  occurs due to over-dilatation of the
balloon(beyond the recommended burst pressure.)
Horizontal Rupture: occurs when there is structural defect in the
balloon catheter due to defective manufacturing process. The
balloon can rupture before RBP.
Pinhole Rupture: Localized rupture which can occur in the
balloon due to injury by a calcified spicule or an exposed stent strut.
(can rupture even before RBP.)

38. Management of balloon rupture depends upon trauma
inflicted on the vessel wall by the ruptured balloon.
 Most of the complications due to balloon rupture can
be managed conservatively.
Balloon rupture may sometimes require placement of
covered stents or surgery.

39. BMV BALLOONS

47. SUMMARY
Materials used for balloon manufacture now are
polyethylene terephthalate (PET) or nylon
Low-pressure, elastomeric balloon are made of latex or
silicone that is used primarily in fixation and occlusion.
High pressure balloons are thin-walled and exhibit high
tensile strength
OTW balloon catheters useful when enhanced
trackability is required

48. Rated Burst Pressure (RBP) is the pressure below which
99.9% of the balloons will not burst upon single
inflation
Semi complaint balloons are used for pre-dilatation of
lesion before stent implantation
Cutting balloons reduces vessel stretch and vessel injury
by scoring the vessel longitudinally

49. Thank you