Basics of PCI

1. Basic principles of the procedure
Frijo Jose A

4. Comparison-
Diagnostic v/s Guiding catheters
• Stiffer shaft
• Larger internal diameter (ID)
• Shorter & more angulated tip (110º vs. 90º)
• Re-enforced construction (3vs.2 layers)

5. Guide catheter construction

6. Curves in guide catheter

7. Guiding catheter
• For each given size of, its ID is either a
standard, large or giant lumen
• Larger sizes –
– better opacification of the contrast
– better guide support
– allow pressure monitoring
increased risk of ostial trauma, vascular
complications and the possibility of kinking of
catheter shaft

10. Judkins and Amplatz
Judkins
• Extremely useful as a diagnostic cath - 1⁰ curve is
fixed
– Intubates small segment of ostium - ↓risk of trauma
• Limitation while performing PCI - 1⁰ curve is fixed
– May not be co-axial as cath makes an angle of ~90º
with cor - may be difficult to pass balloons-esp LCX
JL- point of contact on asc Ao -very high &
narrow- ↑ chance of prolapse & dislodgement
JR- no point of contact on asc Ao - extremely poor
support

11. Backup force
• 3 factors
– Catheter size
– Area of contact made by cath on Ao
– Angle (theta) of cath on the reverse side of Ao
• The angle (theta) determines the force that
can dislodge the guiding catheter.

13. If this angle is ≈90⁰, it results in a
greater backup force. Therefore a
lower position is preferable as the
point of contact on the reverse side
of the aorta because the angle
approaches 90º

15. Other Guiding Catheters
Long tip cath like Xtra backup (XB) & Extra back up (EBU)
• modifications for JL- stiffer & free 1⁰ curve
• more co-axial & ↑support
– XB distal tip - lies more horizontal within cor, sometimes
pointing ↑, & intubating more LMCA
– Longer segment of XB cath comes in contact with contra-
lat wall of Ao- ↑ back-up support
• XB cath- ~67% additional support v/s JR- at the cost of
↑ likelihood of trauma LMCA, esp - pre-existing plaque
• ↑stiffer - ↑chance of injury
XBLAD - ↑support for LAD interventions specifically

16. Xtra backup (XB) tip

17. Guide Catheter for RCA Interventions
• JR or Hockey Stick (HS) is usually preferred
• Extra-support-(CTO/tortuous)- AL1
• MP cath- esp abn take-off, esp inf
• Three dimensional right curve (3 DRC) cath-
tortuous, bent anatomy & postr/supr take off
of RCA
• XBR & XBRCA -new caths specifically for inf &
sup take off of RCA respectively

19. Guide Catheter for LCX Interventions
• JL 4 may be gently rotated clockwise to achieve a
stable co-axial alignment
• Ao root dialated / if JL 4 points anteriorly- JL 5
• If additional support –AL cath recommended
– Unlike JL, a simple withdrawal can cause the tip to
advance even furthe- best way to disengage an AL is
to advance it slightly→prolapse tip out of cor & then
rotate it out of the ostium
• Voda cath- esp when a double PTCA of LAD & LCX
in same sitting

20. The Voda catheter

21. Side Holes v/s No Side Holes
• Side holes
– where P gets freq damped (RCA)
– where prolonged intubation of cor mandated (CTO)
– to know P through out PCI (sole surviving art / LMCA)
• P will not be damped
• allow additnl blood flow out the tip- perfuse cor
• may also avoid catastrophic dissections in the ostium
of the artery if the guide catheter is not co-axial
 it can be a false sense of security → Ao P, not cor P is
being monitored
 suboptimal opacification
 ↓back up support- weak cath shaft & kinking at side
holes

22. Guide Techniques for PCI of Tortuous Arteries
Deep Seating of Guide
• cath deeply intubated into cor- ↑support
• RCA/LCX - clockwise rotation & gentle
advancing of guide over the guide wire
• LAD - counterclockwise rotation
↑ risk of dissection & embolization, esp
degenerated SVG

23. Guide Techniques for PCI of Tortuous Arteries
Child in Mother Technique
• 110cm long 5Fr guide (Child) in 100cm long
6Fr/7Fr guide catheter (Mother)
• May provide up-to 70% more support
• Trauma to vessel →dissection
• Air embolism usually occurring during
intubation of child catheter/during CAG
performed via mother guide

24. Shepard's Crook RCA
• Dramatic upturn with a ≈180º switchback turn
• AL1/0.75 & 3DRC are best suited for this
anatomy

25. Guide wire - construction
• Most - calibre of 0.014 inch
• Multi-layer constructions:
1. Core element (usually stainless steel/or nitinol): tapers
at variable points towards wire tip to impart differential
stiffness along wire's length
2. Terminal coil segment (often 30mm length; usually
radio-opaque material e.g. platinum/iridium alloys):
gives flexibility and allows wire tip to be shaped per
operator requirements
3. Coating: most wires – silicone/Teflon outer coating to
aid easy advancement. Some coated with a hydrophilic
polymer coating that becomes a gel when wet to reduce
surface friction and increase wire ‘slipperiness’

26. Guide wire - construction
• Most - calibre of 0.014 inch
• 3 main components of guidewire design:
– central core
– outer covering
– flexible distal tip
• The wire tip may be further subdivided into
spring coil & short distal tip weld
• Also, all guidewires have a specific surface
coating applied

27. Central core
• Longest & stiffest portion of guidewire
• Tapers distally to a variable extent
– 2-piece core- distal part of core does not reach
distal tip of wire→ shaping ribbon, extends to
distal tip
– 1-piece core- tapered core reaches distal tip weld
• 2-piece →easy shaping & durable shape
memory
• 1-piece →better force transmission to tip &
greater “tactile response” for operator

29. Central core
• Stainless steel
– superior torque characteristics, can deliver more
push, provides good shapeability of tip in core-to-tip
design wires
– more susceptible to kinking
• Durasteel- better tip shape retention and
durability
• Nitinol
– pliable but supportive, less torquability than SS
– generally considered kink resistant & have a tendency
to return to their original shape, making them
potentially less susceptible to deformation during
prolonged use

30. Distal tip
• Flexible, radio-opaque part
• Consists of spring coil extending from distal
untapered part of central core to distal tip weld
• Integrates tapered core barrel (as well as shaping
ribbon in 2-piece wire)
• Spring coil-variable length (1-25cm)-radio-opaque
section located at its terminal end
• Distal tip weld- short (≤2mm)compact cap
forming the true distal end of the wire - to ↓
trauma while the wire is traversing vessels

32. Wire Coating-hydrophilic/hydrophobic
Hydrophobic
• Repels water - requires no actuation/wetting
• ↓friction (to ½ V/S no coating), ↑trackability
• Preserves tactile feel, allows easier
anchorability / parking - esp CTO
• Silicone, Teflon

33. Hydrophilic
• Attracts water - needs lubrication
• Thin, slippery, non-solid when dry→ becomes a gel when
wet
– ↓friction(⅙ no coating) →glide through tortuous
– ↑trackability
– ↓Thrombogenic
↓tactile feel- ↑risk of perforation
Tendency to stick to angioplasty cath
• Useful in negotiating tortuous lesions and in “finding
microchannels” in total occlusions
• Lubricity is highest with hydrophilic wires, less with
Silicone coating and least with PTFE or Teflon coating

34. Properties Of An Ideal Guidewire
• Push transmission/steerability
• Torque transmission/torquability
• Body support/ trackability
• Tip support/mobility
• Flexibility
• Tip durability/elasticity
• Tip visibility and markers
• Tactile feedback
• Prolapse tendency

35. • Push transmission/steerability: ability of a guide wire tip to be delivered to
the desired position in a vessel
• Torque transmission: ability to transmit rotational forces from the
operators hand to the tip
• Body support/ trackability: ability to advance balloon catheters/other
devices on guidewire
• Tip support/mobility: Allows moving the distal tip to search for the true
lumen
• Tip durability/elasticity: Permits shape memory retention of the distal tip
throughout
• Tactile feedback: “feel” of the wire tip’s behavior, as perceived by the
operator
– better appreciated with non-coated / hydrophobic coated, coil tipped wires and
it ↓with hydrophilic coating

37. Shapeability and shaping memory
• Shapeability - allows to modify its distal tip
conformation
• Shaping memory - ability of tip to return back to
its basal conformation after having been exposed
to deformation & stress
– Both do not necessarily go in parallel
– SS core wires -easier to shape (↑memory- nitinol
core)
– 2-piece core + shaping ribbon - easier to shape &
↑memory
• General rule- when negotiating a vessel with J
loop, distal bend ~ D of vessel—more bend -
↑wire tip prolapsing, less bend -↓ steerability

38. Types Of Guidewires
• Depending on tip load- Balanced, Extra
support, Floppy
• Tip load- force needed to bend a wire when
exerted on a straight guide wire tip, at 1 cm
from the tip
– Balanced – 0.5-0.9g
– Extra support - >0.9g
– Floppy - <0.5g

39. • Workhorse wire: default choice - balance btw
stiffness/support & flexible tip – majority
lesions
• Stiff wires: offer extra support for
tortuous/calcified cor
• Floppy wires: when vessel trauma is a concern
(e.g. re-crossing a dissected lesion)

40. Workhorse (frontline) Guidewires
• ATW/ATW Marker
• Stabilizer
• BMW / BMW Universal
• Zinger
• Cougar XT
• Asahi Light / Medium
• Asahi Standard
• Asahi Prowater Flex
• Choice Floppy
• Luge
• IQ
• Forte Floppy
• Runthrough NS
• Galeo

41. Balance Middleweight Universal wire
(Abbott Vascular/Guidant, Santa Clara, CA)
• Quite steerable - tip is suitable for bending in a “J”
configuration for distal advancement into the distal vessel
bed with minimal trauma while still maintaining some
torque
• shape retention relatively poor -any J configuration tends to
become magnified over time → consequent loss in
steerability
• moderately torquable- progression - minimal friction (light
hydrophilic coating) - Dye injection may also be helpful to
propagate distal advancement
• suitable for rapid, uncomplicated interventions
• low risk to cause dissections/distal perforations
• support - low to moderate

42. Balance Middleweight wires
• from the generation previous to the Universal
• lack light hydrophilic coating at the tip→ more
steerability but requires greater effort for
distal advancement
• more direct tactile feedback (v/s more
automatic progression –Universal)
• Support-moderate
-power steering-

43. Runthrough NS® wire
• unique dual core design
– main shaft core of SS & a distal core of nitinol
alloy, which extends into a nitinol shaping ribbon
• distal tip is hydrophilic coated

44. Runthrough NS® wire

45. Guidewire Strategies for Approaching CTO
• A) Guidewires for
Approaching Micro-channels
– Crosswire NT
– Whisper / Pilot
– Rinato
– Shinobe / Shinobe Plus
– ChoICE PT / ChoICE PT ES
– PT Graphix
– PT2
• B) Guidewires for Drilling
Strategy
– Persuader
– Miracle Bros
– Cross-It
• C) Guidewires for Penetrating
Strategy
– Cross IT
– Conquest Pro
– Liber 8
• D) Guidewires for Retrograde
Technique
– Fielder/FielderFC
– X -treme
– Whisper
– ChoICE PT2
– Runthrough / Runthrough
Hypercoat

46. CTO
• Start with the intermediate wire
• This provides 3g of distal force and moderate
support
• Conventional stainless steel core wire with
30mm of tip radio-opacity and 0.014 in.
diameter
• If this wire fails to cross, → Miracle series

47. Intermediate Wire (Asahi Intecc)
• ●Tip load ............................... 3.0 g
• ●Tip radiopacity .................... 3 cm
• ●PTFE coating over the shaft

48. Miracle series (Asahi Intecc)
• 0.014 in wires - specifically designed for CTO
• 110mm of distal tip radio-opacity for optimal
visualization
• Come in 4 versions of ↑ distal force:
3g, 4.5g, 6g, 12g

49. ●Tip load ............................... 3.0 g
●Tip radiopacity .................. 11 cm
●PTFE coating over the shaft

50. ●Tip load ............................... 4.5 g
●Tip radiopacity .................. 11 cm
●PTFE coating over the shaft

51. ●Tip load ............................... 6.0 g
●Tip radiopacity .................. 11 cm
●PTFE coating over the shaft

52. ●Tip load ............................. 12.0 g
●Tip radiopacity .................. 11 cm
●PTFE coating over the shaft

53. Conquest series (Asahi Intecc)
• The next evolution- tapered tip Conquest wire (Confianza)
– Has a distal tip diameter of only 0.009 in
– The distal tip is radio-opaque for 200mm
– Provides 9g of distal force
• Conquest Pro (Confianza Pro)
– Also tapered to 0.009 in
– Provides 9g of force
– Hydrophilic-coated for the distal 20 cm
Tip tapering is proposed to help the wire find and navigate
microchannels in the occluded segment, while the hydrophilic
coating of the Conquest Pro reduces the tip friction by about one-
third

54. ●Tip load ............................... 9.0 g
●Tip radiopacity .................. 20 cm
●Tip outer diameter ...... 0.009 inch (0.23 mm)
●PTFE coating over the shaft

55. ●Tip load ............................... 9.0 g
●Tip radiopacity .................. 20 cm
●Tip outer diameter ...... 0.009 inch (0.23 mm)
●SLIP COAT coating over the spring coil
●PTFE coating over the shaft
The distal tip is not coated to allow it to catch on
the entry point of the lesions

56. ●Tip load ............................. 12.0 g
●Tip radiopacity .................. 20 cm
●Tip outer diameter ...... 0.009 inch
●SLIP COAT® coating over the spring coil
●PTFE coating over the shaft
For penetration of calcification and proximal
or distal thick, fibrous caps

57. ●Tip load ............................. 22.0 g
●Tip radiopacity .................. 17 cm
●Tip outer diameter ...... 0.008 inch (0.20 mm)
●SLIP COAT® coating over the spring coil
●PTFE coating over the shaft
Designed for crossing complex lesions with heavy
calcifications and tough fibrous tissues
Finest and stiffest guidewire in the current Asahi
series.

58. Fielder™ / Fielder FC™ (Asahi Intec Co.)
• Special guidewire - distal coil coated with
polymer sleeve & further coated with a
hydrophilic coating
• Provides advanced slip performance &
trackability for highly stenosed lesion & tortuous
vessels
• Very good torque performance
• Combines both slide and torque performance
• Primary wire used in the retrograde technique of
recanalization of CTO

59. Tip load ............................... 1.0 g
Tip radiopacity .................... 3 cm
Polymer sleeve length ..... 22 cm
SLIP COAT coating over the spring coil
PTFE coating over the shaft

60. ●Tip load ............................... 0.8 g
●Tip radiopacity .................... 3 cm
●Polymer sleeve length ..... 20 cm
●SLIP COAT coating over the spring coil
●PTFE coating over the shaft

61. ●Tip load ............................... 0.8 g
●Tip radiopacity .................. 16 cm
●Polymer sleeve length ..... 16 cm
●Tip outer diameter ...... 0.009 inch（0.23 mm）
●SLIP COAT® coating over the spring coil
●PTFE coating over the shaft

64. Galeo guide wire

65. Optimum guide wire positioning
• Should be placed as distally as possible in the
target vessel
• Allows extra support when crossing with
balloon/stent catheters
• ↓ chance of the wire becoming displaced
backwards across the lesion and necessitating
re-crossing
Avoid vessel perforation when positioning
wires with hydrophilic coatings very distally

66. Plain ‘old’ balloon angioplasty
• 1977- Andreas Gruentzig
• 1st gen balloon cath - fixed to guidewire - difficult
to cross tight/tortuous lesions
• Initially, over-the-wire systems → new monorail
systems
– Short guidewires
– Facilitates performance of PTCA by a single operator
• Progression in balloon technology
– different type, better materials, better coatings,
lower-profile systems, improved delivery, ↑burst
pressure, ↓compliance

67. Balloon technology

68. Construction of the balloon catheter
(monorail type)
Only the distal 15–25 cm of the balloon catheter tracks over the guidewire
1. less procedural time
2. a single operator
3. reduced fluoroscopy time
4. no additional devices for the exchange

69. The catheter has a lumen through its entire length that tracks over a guidewire
Guidewire and balloon catheter move independently of each other
1. two operators
2. can exchange balloon catheters only with a 300 cm exchange length wire or specific
products (Trapper or Magnet) in order to maintain the wire position across the lesion
3. increased exposure to radiation because the fluoroscopy needs to be on during the
placement of the balloon

70. The guidewire and balloon are on the system
1. The guidewire cannot be advanced independently over the Balloon
2. Fixed system- does not allow for guidewire exchange
3. Has the lowest profile
4. Inability to exchange for another balloon catheter without having to recross the lesion
5. Need to remove the whole system if the wire tip becomes damaged

71. Either an over-the-wire or a monorail design
Perfusion side holes proximal and distal to the actual balloon
As the balloon is inflated, the perfusion side holes allow blood to enter the catheter through the
proximal holes, flow within the inflated balloon, and exit the catheter’s distal side holes
•Balloon can be inflated for longer periods of time
•Specific situations- cor perforation & abrupt closure, that cannot be recovered by a stent
•Decreased trackability due to its larger diameter

72. Balloons
Distal tip -usually tapered- allows to cross lesion
less traumatically
• Profile of the distal tip will determine how
much push is needed to get across the lesion
• Coating – also determinant for ability to cross
– A hydrophilic coating- superior in crossabilty
– A slippery characteristic- not suitable for in-stent
restenosis- balloon will easily slip out of the lesion
when inflated

73. Performance Parameters
• Low entry & crossing profile- for optimum
tracking & crossing
• Short inflation & deflation time- to avoid
ischemic complications
• Optimum refolding characteristics- to avoid
traumatization or stent damage
• Predictable balloon compliance- to allow precise
diameter sizing
• High balloon-burst strength- for high-pressure
dilatations
• Low bending stiffness- for easy tracking of curved
vessels

74. Profile
• Largest diameter in the balloon region
– To position balloon safely across tight lesions,
↓possible profiles required
– To cross extremely tight & long lesions, both entry
& crossing profiles must be ↓
– ↓profiles -to avoid luminal obstructions

75. Maximum Profile of PTCA Balloon Catheters
Distal profile
(mm)
Proximal profile
(mm)
Medtronic
Sprinter 3.0/20
mm
0.85 1.00
Biotronik Elect
3.0/20 mm 0.85 1.00
Guidant Voyager
3.0/20 mm 0.80 0.95
Boston Scientific
Maverick23.0/20
mm
0.85 0.95
Cordis AquaT3
3.0/20 mm 0.80 0.95

76. Inflation & Deflation Time
• Inflation of a balloon within a narrowed, but
not completely occluded, blood vessel results
in ischemia of the dependent tissue
• To ↓ ischemic time - ↓ obstruction time
• Obstruction time =time required to transmit
pressure in the hand pump to the balloon +
time for balloon inflation + deflation time

77. • Resistance,R- determined by viscosity, inner
radius r & length l of the hypotube
• Poiseuille's law
– So r of the tubing- major determinant of resistance
– Low-caliber - long inflation/deflation time→limit on ↓
catheter shaft profiles
– Inflation & deflation times depend on volume of
balloon- not useful in balloon comparisons
• For balloon inflation, a clinically relevant mixture
of saline & contrast agent (1:1) should be used

78. • Deflated balloon remains within lumen &
obstructs blood flow
• To minimize residual obstruction & to avoid
vessel damage by “flaring”•
of unfolded balloon
parts on retraction, the geometric refolding
characteristics of balloon after deployment-
important
• ↓cross-sectional area & smooth profile of
refolded balloon - least blood-flow obstruction,
avoids vessel traumatization, stent damage on
withdrawal

79. Average deflation time of PTCA balloon catheters

80. Balloon Compliance
• Change in balloon D for a given change in
balloon P
• Can be either indicated as a %↑in D/bar, or
listed as a table of P & corresponding balloon
D- 1st useful for classification of balloons as
noncompliant/semicompliant, latter is usually
given by the manufacturer for each device as
the compliance chart

81. High to moderate compliance balloons
• Polyolefin copolymer (POC)
• Polyethylene (PE) [< than POC]
Balloon sizing important – oversizing can easily
occur
Tend not only to stretch in D but also to
overexpand into the areas of least resistance, i.e.
prox & distal to lesion –(‘dog-boning’)- dissection
observed more commonly
Crossability may be superior

82. Nylon
• Thick material- compliant at ↑pressures
• ↑ mean burst pressures

83. Non complaint balloons
• Polyethylene terephthalate (PET)
thicker-walled balloon
Allow work at higher pressures
hard calcified lesion or post-stent dilatation

84. (a) A compliant balloon tends to be oversized at the edges, with less
dilatation at the obstructive segment of the lesion (‘dog-boning’)
(b) A noncompliant balloon gives a predictable amount of pressure at the
lesion without uncontrolled radial and longitudinal growth

85. D Compliance of High-pressure PTCA Balloons
Diameter compliance
(%/bar)
Medtronic Sprinter
3.0/20 mm
9.92
Biotronik Elect 3.0/20
mm
5.50
Guidant Voyager 3.0/20
mm
8.99
Boston Scientific
Maverick23.0/20 mm
9.88
Cordis AquaT3 3.0/20
mm
5.88

86. Balloon Burst Strength
• The radial & axial stresses (σrad, σax) depend on
balloon pressure p, balloon diameter d, &
thickness s of balloon wall
– Balloon will burst if stresses exceed rupture stress of
the material
– Stress- linear correlation with P & D, and inverse
relationship to balloon thickness
– Given the same material, a larger balloon diameter &
thin balloon material →↓burst P
– Also within the balloon axial stress is ½ as big as radial
stress

87. • RBP→ the maximum recommended P for safe
use - 99.9% of the tested balloons will not fail
at RBP with 95% confidence
• Nominal P→ the P at which balloon will have
expanded to the manufacturer-specified size
– e.g. a 2.5mm D balloon expanded to nominal P
should have an external diameter of 2.5mm

88. The dilating force
• Pressure (hydrostatic force) put in the balloon
• Tension determined by
– balloon diameter,
– balloon material/compliancy, and
– vector force (the amount of constriction)
• Therefore, balloon size and balloon
compliance are the major determinants for
successful mechanical dilatation

89. In IVUS , dissection is observed in up to 60–70% of dilated segments
Dissection may be necessary for optimal results after POBA

90. • Long lesions(>20mm)- may be treated with
long balloon to avoid dissection at edges
• Soft lesions(recent)-↑lipid conc-↓inflation P
• Calcified lesions(cholesterol, conn tissue,&
muscle cells)-↑dissection/perforation chance
-NC balloon-allows ↑inflation P to crack lesion
• Calcified lesions & post stent dilatation-
↑rated burst P & shorter balloons better
• Size of balloon- based on ref vessel D -
balloon/artery ratio of ~ 1.1 currently recom

91. • Trackability
– ability of a system to be advanced to a target lesion
– affected by several technical parameters such as
friction, bending stiffness etc
• Crossability
– ability to pass stenoses
• Pushability
– load transfer from interventionist‘s end to the distal
tip of catheter High load transfer allows finer & more
direct tactile control of the instrumentation
• Even small obstructions that cause only a minor ↑ in
reaction forces at the catheter tip can be felt by the
operator, allowing him to tune and finely adjust the pushing
force to overcome the obstacle while utilizing the least
injurious maneuver

92. Crossing Difficult Lesions
Following techniques
• use of stronger back-up catheters
• deep insertion of guide
• adding vibration
• Pushing balloon while pulling guidewire
• use of a stiff guidewire
• Buddy wire technique

93. Elect: Fast-exchange Balloon Catheter
• Low shaft profile- compatible with smaller
guide (5F compatibility for all balloon sizes)
• Hydrophilic coating improves gliding
• Soft Tapered Tip(Laser-rounded)-↑safety &
crossability
• Embedded Platinum-Iridium Markers-
optimized visibility, ↓crossing profile

94. Lesion entry profile 0.017"
Shaft diameter Proximal: 2.0F; Distal: 2.4F
(Ø1.25-1.5mm) , 2.6F (Ø 2.0-3.5mm),
2.7F
(Ø 3.75–4.0 mm)
Recommended guide catheter 5F (min. I.D. 0.056")
Nominal Pressure 7 bar
Rated burst pressure (RBP) 18 bar (Ø 1.25mm), 16 bar (Ø 1.5-
2.25 mm),
14 bar (Ø 2.5-4.0mm)
Elect: Fast-exchange Balloon Catheter

95. Pleon
• Superb pushability & crossability- esp suitable
for reaching difficult target lesions
• laser-rounded soft tip
• hydrophilic coating

96. Jocath Mercury PTCA Catheter

97. Jocath Mercury PTCA Catheter
Balloon Compliance: Semi-compliant
Shaft Diameter: 2.0F proximal
2.7F distal
Shaft length: 140-145 cm
Lesion Entry Profile: 0.017"
Nominal Pressure: 8 bar
Rated Burst Pressure: 16 bar
Average Burst Pressure: 22 bar
Coating: HYDREX Coating System
Min. Guiding Catheter: 5F (0.058")

98. NC Mercury PTCA Catheter
• Maximized wall apposition due to NC balloon
behavior
• Minimal balloon overhang- to limit vessel
injury during high P dilatation
• Minimal tip flaring
• Fast deflation time
• Efficient access- low entry profile

99. Coronary stents

100. • Ulrich Sigwart & Joel Puel in 1987 implanted
the first stent in a human coronary artery in
Toulouse, France

101. TYPES OF STENTS
• Metal composition
• Open v/s closed cell designs
• Thickness of struts
• Eluting drugs
• Stent design may be specific -small (<2.5 mm
diameter) vessels / bifurcation lesions

102. Metal composition
• Cobalt-chromium - more deliverable for
challenging lesions
• Stainless steel designs - greater radial strength
for bulky lesions or those involving more
muscular aorto-ostial locations
• Co-Cr - stronger & more radiopaque than SS
→ thinner struts, lower profiles (<0.40”),
better flexibility & similar radial strength

103. Stent structure
• Slotted tube stents
• Modular stents
• Multicellular stents
• Modular-multicellular stent (hybrid stents)

104. Slotted tube stents
• Slotted tube stents are made just by cutting
longitudinal slashes in tubes

105. Modular stents
• Consist of several crown-shaped modules,
which may be manufactured from metal wires
that are punctually connected to form a tube
– ie, based on repeating identically designed units,
again laser-cut, linked together by welded struts
• An ‘open-cell’ design
• Highly flexible
• Offer better side-branch access
– Boston Scientific Express stent

106. • Open-cell/modular stent design
• Multiple repeating modules are linked at
certain points of the design, giving flexibility
but less metal : artery coverage
• Medtronic DriverTM stent

107. • The Palmaz-Schatz stent
• Based on repeating modules

108. Multicellular stents
• Completely closed cell design
• Less flexible
• Uniform vessel wall coverage preventing
tissue prolapse
– Guidant Multi-Link

109. • Closed-cell stent design
• Modern closed-cell stents have relatively large
cells
• Boston LiberteTM stent

110. Modular-multicellular stent
• Also called hybrid stents
• Try to combine the advantages of multicellular
and modular stents
– Lekton Motion, Pro Kinetic

111. Cell design
Closed cell (in which each ring is interconnected)
• more support
less flexible
Open cell
• improves flexibility
• improves sidebranch access
reduce radial support

112. • Strut- single element that forms larger structural
entities such as cells, rings, or crowns
• Cell - small but regularly repetitive structure of a
stent
– Open cells have a more complicated structure than
closed cells
– Cells represent the elementary geometrical figure of
the stent- will deform during stent expansion
• Rings and crowns- comprise a cluster of cells
forming a higher-order geometrical pattern of the
stent, which may form complete stent segments
usually coupled by longitudinal bridges or links

113. Strut thickness
• Thinner struts - ↓ vessel injury
• Strut thickness <100 microns - thin strut stents

114. Stent coating
• The eluted drug is linked by a
degradable/permanent polymer coating only
a few micrometers in thickness
– not expected to change mechanical strength
– may affect surface friction

115. • Provides local delivery of a drug
• Methods for the storage and controlled release
– Nondegradable or biodegradable polymer
– Cavities on the stent struts- drug depots
– Small amounts of drugs applied directly to stent surface
• Nondegradable polymers- polyurethane, silicone,
polyorganophosphazene, polymethacrylate,
poly(ethylene terephthalate), & phosphorylcholine
• Biodegradable polymer- poly(l-lactide), poly(3-
hydroxybutyrate), polycaprolactone, polyorthoester,
fibrin

116. DES- mechanism of benefit
• Late lumen loss and restenosis after nonstent interv -
combination of acute recoil, negative remodeling
(arterial contraction), and local neointimal hyperplasia
• Late lumen loss after stenting - solely to in-stent
neointimal hyperplasia
• The restenosis benefit of DES compared to BMS results
from inhibition of in-stent neointimal hyperplasia ,
which is reflected as a lesser degree of late in-stent
lumen loss at 6-9/12 (0.2 to 0.4 versus 0.9 to 1.0 mm
with BMS) -Neointimal suppression is still sustained at
2years

117. • In the Ontario registry the benefit was limited
to those patients with two or three risk factors
for restenosis (diabetes, vessels <3 mm in
diameter, and lesions ≥ 20 mm in length)
• In the Swedish Coronary Angiography and
Angioplasty Registry (SCAAR), the benefit with
DES compared with BMS was most apparent
when any one of these high risk features was
present

118. Sirolimus
• aka Rapamycin- immunosuppressant drug - macrolide
• First discovered from Streptomyces hygroscopicus in
Easter island soil sample— island aka "Rapa Nui",
hence named
• Originally developed as an anti-fungal agent
• Sirolimus is lipophilic - crosses cell membranes – binds
FK binding protein-12 (FKBP-12)→an active complex
• Sirolimus:FKBP-12 complex→binds & inhibits
mammalian Target Of Rapamycin (TOR)
• Inhibition of this enzyme→↓cytokine-dependent
cellular proliferation at G1 to S phase of cell cycle
• The mechanism of inhibition is cytostatic rather than
cytotoxic as the affected cells remain viable

119. Paclitaxel
• Mitotic inhibitor isolated it from bark of
the Pacific yew tree, Taxus brevifolia, hence
named taxol
• Stabilizes microtubules→ interferes with the N
breakdown of microtubules during cell
division→prevents DNA synth
• Paclitaxel-inhibited cells remain at the G0/G1 and
G2/M interfaces of the cell cycle
• Cells exposed to paclitaxel undergo apoptosis/cell
death- cytotoxic

120. •

121. Everolimus
• A rapamycin analogue
• Novel macrolide with potent
immunosuppressive & antiproliferative effect
• Arrests cell cycle at the G1 to S phase

122. Biodegradable stents
• Intended to support a vessel for just as long as is
necessary to complete the healing process and
to then disappear after a specified time period
• Complications resulting from long-term
intravascular presence of a FB- thrombogenicity,
permanent mechanical irritation, prevention of
positive remodeling, are eliminated
• Poly(L-lactic acid) (PLLA), poly(D-lactic acid)
(PDLA), poly(e-caprolactone) (PCL), poly(glycolic
acid) (PGA)

123. Scanning electron micrograph of a
PLLA stent prototype

124. NexgenTM Cobalt Chromium Coronary Stent System
• Hybrid cell design
• Ultra-low strut thickness of 65µm
• The balloon overhang is 0.3mm ensuring that
balloon related injury is marginalized

125. Stent Material
: Cobalt Chromium
L605
Strut Thickness
: 65 µm (0.065mm or
0.0026")
Stent Diameters (mm)
: 2.50, 2.75, 3.00,
3.50, 4.00, 4.50
Stent Lenghts (mm)
: 8, 13, 16, 19, 24,
29, 32, 37, 40
Mean Foreshortening : 0.29%

126. genX™CrCo coronary stent
Stent material L605 Co-Cr alloy
Design 10 Crown , variable – geometry
Strut thickness 65 micro meters
Strut Width
Large 70 micro meters Small 60
micro meters
Guiding catheter 5 Fr compatible
Crossing profile < 1 mm

127. genX™ coronary stent
Stent material
SS316L Stainless
Steel
Design
10 Crown , variable –
geometry
Strut thickness 105 micro meters
Strut Width
Large 85 micro
meters Small 75
micro meters
Guiding catheter 5 Fr compatible
Crossing profile < 1 mm

128. Lekton Motion
• Combines cell pattern & Z-shaped connections
• Strut thickness of 90µm
• Ultra low profile (<1.00mm) permits excellent
tracking & crossing
• Also available in 2 versions: Petite (vessels
<2.5mm) & Mega (vessels >4mm)

129. • Petite
– 80 µm struts
– Small vessel design with lowest crossing profile
– Shaft with Enhanced Force Transmission
technology permits exellent positionning in distal
anatomy
• Mega
– Compatible with 5F guide catheters in all sizes
– Special design for optimal flexibility and support
of large vessels (>4mm)
– Maximum expansion: 5.5 mm

130. PRO-Kinetic
• Cobalt Chromium Stents
• Struts- 60 µm (0.0024“)
• 3 Different Design
– Specific designs for small, medium and large arteries
• Low Profile
– Low profile (0.95 mm) permits easy track & cross
• Double Enhanced Force Transmission Shaft (EFT)
– ↑shaft flexibility & kink resistance
• Hydroglide coating
• ↓Shaft Profile- all sizes compatible with 5F space
stents

131. Angstrom
• Material- 316LVM Stainless Steel
• Non-Ferromagnetic
• Strut Width 0.09 mm
• Closed-cell design
• Profile before Delivery < 1mm

132. genXsync
• Uniform sinus design
• Alternate ‘S’ link offers excellent flexibility
• Biodegradable polymer in single layer→initial
burst of sirolimus followed by sustained elution up
to 40 days
• Polymer degrades by hydrolysis & enzymatic
→excreted in form of CO2 & H20
• PTFE hypotubing shaft- improved pushability
• Super thin alloy (65µm) with ultra thin coating
(3µm)
• Low crossing profile drug eluting stent (< 0.85 mm)

133. Stent material L 605 Chromium Cobalt
Design
Uniform sinusoidal cell
design
Coating
Bioresorbable and
biodegradable polymers
Drug Sirolimus
Strut thickness 65 µm
Strut width 85 µm
Nominal foreshortening Nearly zero
Recoil < 4.0%
Guiding Catheter 5 Fr Compatible
Crossing Profile < 0.85 mm

134. CYPHER® Stent
Stent Geometry Closed-cell FLEXSEGMENT™
Technology
Material 316L Stainless Steel
Strut Thickness .0055"
Crimped Profile .044"
Available Sizes
Diameters: 2.25, 2.50, 2.75,
3.00, 3.50 mm
Lengths: 8, 13, 18,23, 28, 33 mm
Drug Delivered Sirolimus
Mechanism of Action
Inhibits m TOR to block growth
factor induce proliferation
Cytostatic
Drug Delivery Vehicle Controlled-release,
nonresorbable,
elastomeric polymer coating
Drug Release Kinetics
80% of sirolimus released in 30
days
Approval Status Approved by FDA

135. Biomime

136. Angstrom lll
• Closed-cell design
• Stainless steel
• Paclitaxel eluting

137. XIENCE V
• 0.0032” strut thickness
• Clinically proven MULTI-LINK VISION CoCr
stent

138. Endeavor Sprint Zotarolimus-Eluting
Coronary Stent System

139. • Attempts to ↓ the amount of balloon
protrusion outside the stent →↓vessel
trauma in adjacent cor segs
• A perfect match not yet achieved
• Diffuse disease- Minimal balloon overhand
• Significant vessel tapering- Minimal balloon
overhand

140. A = plaque compression
B = superficial tear/fissure
(intimal)
C = deeper sub-intimal
tear
D = subintimal tear with
localized dissection
E = deep subintimal tear
with extensive dissection
reaching media
F = circular sub-intimal
dissection
In eccentric lesions,
stretching of vessel wall
(without plaque)
and sub-medial dissection
can occur

141. Vessel size
• In the beginning - elective stent deployment
limited to large cor (≥ 3 mm)
• STRESS trial →elective stenting provided
superior angiographic & clinical outcomes in
vessels <3 mm (stented using 3 mm stents)

143. Optimal stenting
• Deployment with only minimal residual
luminal stenosis -↓risk of both ST & ISR
• Suboptimal luminal dilation
– inadequate balloon expansion (related in part to
plaque characteristics) &
– elastic recoil ( asso with stent design & resistance)

144. • STARS→ 265 (13.5%) of 1,965 pts enrolled met
prespecified criteria for suboptimal stenting
• (defined as residual stenosis >10 percent,
evidence of stent thrombosis, dissection or
abrupt closure, absence of TIMI III flow, or
need for three or more stents)
Acute and nine-month clinical outcomes after "suboptimal" coronary stenting: results from the
STent Anti-thrombotic Regimen Study (STARS) registry J Am Coll Cardiol 1999 Sep;34(3):698-706.

145. Suboptimal stenting
• ↑periprocedural NSTEMI (8.7 v/s 4.2 %)
• ↑overall 30 day mortality (1.1 v/s 0.06 %)
• ↑clinical restenosis (27 v/s 16 %)
• ↑ 9/12 MACE(death,MI,TVR), esp due to
↑NSTEMI(9 v/s 4.6 %) & TVR(15.5 v/s 10.2 %)
Acute and nine-month clinical outcomes after "suboptimal" coronary stenting: results from the
STent Anti-thrombotic Regimen Study (STARS) registry J Am Coll Cardiol 1999 Sep;34(3):698-706.

146. Role of predilation
classic approach
• Predilation→ stent deployment→ high-P
postdilation
– ↑procedure time
– ↑radiation exposure
– ↑contrast use
– ↑cost

147. • Tight/heavily calcified lesions, esp in tortuous
vessels→ ↑risk of stent dislodgement from
delivery balloon & potential embolization of
the stent
• Predilatation – also preferred when precise
positioning of distal end of the stent is
mandatory- potentially poor visualization of
the vessel distal to the stent may occur,
particularly in critical stenoses

148. Direct stenting
• Theoretically less traumatic to vessel wall
May be esp beneficial in the presence of
thrombus/when treating degenerated SVG
• Direct stenting →↓ procedure time, ↓contrast
• Prox anat landmark- side branch/Ca spot, to guide
stent positioning - helpful during direct stenting
• Use of extra support guidewires & optimal cath
support recommended

149. • Settings in which direct stenting might be
considered
– Vessel ≥ 2.5 mm
– Absence of severe cor Ca
– Absence of signi angulation (>45º)
– Absence of occlusions & bifurcations

150. Direct stenting
Potential Advantages Potential Drawbacks
Avoidance of multiple
exchanges
Failure to track
Less trauma Failure of precise
positioning, incomplete
deployment
Lower rate of “no-
reflow”•
Stent damage or loss
Shorter procedural time Incomplete apposition
Lower procedural costs Traumatization of the
target vessel

151. (BET, SWIBAP, PREDICT, CONVERTIBLE, and TRENDS)
• Major outcomes – similar
(proc success, adv events, MACE)
• Direct stenting for CSA- asso with
↓periprocedural microcirculatory injury v/s
pre-dilation -50 pts - J Am Coll Cardiol. 2008
Mar 18;51(11):1060-5

152. STEMI undergoing PPCI → ↓embolization of plaque
constituents, ↓no-reflow →↑myo perfusion &
salvage
• A randomized comparison DS v/s Conv-( J Am Coll
Cardiol 2002 Jan 2;39(1):15-21) - 206 pts- 102/104-
– Composite end point of slow & no-
reflow/embolization- (DS-11.7% vs. 26.9%, p = 0.01)
– No ST resolution in 20.2% (DS) vs. 38.1%, p = 0.01
• STEMI-Angio & clinical outcomes asso with direct
v/s conv in pts treated with lytic therapy –( Am J
Cardiol 2005 Feb 1;95(3):383-6) - Direct stenting -↓death,
MI, or CCF during hosp & at 30 days -
independently asso with ↑ in-hospital outcomes

153. Spot stenting
• Using the shortest possible stent only in the particular
segments of a lesion - proposed by Colombo &
colleagues
– Attractive strategy, given the poor outcomes of long
lesions treated with very long (>32 mm) stents
• Clinical events & TLR ↓in spot stenting gp than in
conven (22% v/s 38% & 19% v/s 34%, resp)- Colombo A, De
Gregorio J, Moussa I, et al: J Am Coll Cardiol 2001; 38:1427–33.
• Use of long stents to treat vessels >3.5 mm in diameter
provides acceptable restenosis rates, whereas
minimizing stent length is important in small vessels

154. Role of high pressure balloon dilation
High (16 to 20 atm) & low (8 to 10 atm)
• Stents usually deployed with a high P
technique utilizing ≥ 12 to 16 atm
• Lower P deployment (8 to 14 atm) -signi vessel
tapering/when prox edge injury is a concern,
as is the case with use of drug-eluting stents
• Most cases- high-pressure postdilation with an
appropriately sized NC balloon at 12 to 16 atm
to achieve full stent expansion

155. Hospital discharge
• Patients undergoing elective stenting are
generally discharged within 24 hours after
stent implantation following overnight
observation and monitoring

156. EPOS trial
• 800 pts elective PCI
• Same-day discharge (after 4hrs of bed rest & 4hrs of ambulation) V/S
overnight stay
• Femoral approach with 5F or 6F guiding catheters, pretreatment with
100mg of asa, single 5000 IU hep, 300mg clopi post procedure in pts who
were stented
• 80%- eligible for same-day discharge in both gps
• Suitability criteria for early discharge -freedom from sympts & absence of
ECG changes & puncture site abn
• Same-day discharge after elective PCI is feasible and safe in the majority
(80%) of patients selected for day-case PCI. Same-day discharge does not
lead to additional complications compared with overnight stay
• Limitations- postprocedural rather than preprocedural clopi; no use of
bivalirudin or glycoprotein IIb/IIIa inhibitors; small catheter sizes and
elective admission for PCI rather than PCI directly following angiography
Heyde GS; Koch KT et al. Circulation. 2007 May 1;115(17):2299-306

157. SAFETY OF MRI
• Based upon available evidence, it appears to
be safe to perform an MRI at any time after
placement of coronary artery stents of any
type