Brief overview of the general principles of interventional radiology, DSA, vascular interventions, catheters, guidewires, patient management, complications

1. GENERAL PRINCIPLES OF ARTERIOGRAPHY
AND VASCULAR INTERVENTIONS
DR ROSHAN VALENTINE
RADIOLOGY RESIDENT
ST JOHN S MEDICAL COLLEGE , BANGALORE

2. OVERVIEW
• HISTORY
• PREPROCEDURE
• CONSENT
• PATIENT EVALUATION
AND MANAGEMENT
• SAFETY CONSIDERATION
• MEDICATIONS
• TOOLS
• CONTRAST AGENTS
• INTRAPROCEDURE
• SEDATION
• ANTIBIOTIC
PROPHYLAXIS
• BLOOD PRESSURE
CONTROL
• ANTICOAGULATION
• VASCULAR ACCESS
• IMAGING
• POST PROCEDURE
• PATIENT MONITORING
• ORDERS
• DISCHARGE CRITERIA
• VASCULAR INTERVENTIONS
• IMPROVING LUMEN
• OCCLUDING LUMEN

4. HISTORY

5. HISTORY

6. PRE PROCEDURE

7. PRE PROCEDURE CARE
CONSENT
• Taken by the doctor WHO DOES THE PROCEDURE /appropriately
trained professional
Patient Needs to Know
• Details of diagnosis and prognosis if left untreated
• options for treatment or management of the condition, including the
option not to treat.
• Benefits and probabilities of success
• Frequently occurring/serious risks involved
• Reminder that patients are entitled to change their minds about a
decision at any time or take a second opinion

8. PRE PROCEDURE CARE -CONSENT
EMERGENCIES
• Provide medical Rx in order to save life or avoid significant
deterioration in pts health
• When pt recovers , inform him what and why the procedure done
Better to have leaflets available for patients prior to the procedure
General Medical Council. Seeking patients’ consent: The ethical considerations. London GMC Publications, 178
Great Portland street, London W1N 6JE.

9. PRE PROCEDURAL CARE
PREPROCEDURAL PATIENT EVALUATION AND MANAGEMENT
 History
 Prior surgery(vascular)
 Mi or stroke
 Diabetes
 Medications
 Prior imaging
 Physical Examination
 Pulse – distal to the site of access
 Check both sides
 Hydrate the patient before the procedure (upto 2 hrs prior)
 LAB
 Platelet count (>50k)
 PT / INR
 Cr Value
 Operator safety – Universal precautions

10. SAFETY CONSIDERATION
• Radiation Exposure
• Fluoroscopy only when needed
• Use pulsed Fluoro modes(Use < 10 pulses per second )
• Wear lead aprons , thyroid shields, leaded glasses, and radiation badges.
• Ergonomic Considerations
• Degenerative disease of neck and spine are common
• Proper positioning of the patient table
• Careful positioning of the controls and monitors

11. PRE-PROCEDURE CARE-MEDICATIONS
Manage risk factors before intervention
• Cessation of smoking
• Medical attention towards DM, HTN , dyslipidemia,
Claudication(Pentoxyfilline/Naftidrofuryl), ulcers

12. PRE-PROCEDURE CARE-MEDICATIONS
Management of pre existing medications before intervention
Warfarin Stop 3 days prior
Check INR previous day (INR <1.5)
Give FFP in emergency
Heparin 3 hours before procedure
Aspirin No need to stop
Clopidogrel No need to stop
Consider using closure devices
Diabetic drugs Metformin: 48 hrs prior , Check RFT before
restarting
Others: On the day of procedure, restart on
taking food
Insulin: Reduce by 50% with 5D infusion
with regular GRBS usage

13. TOOLS
ACCESS NEEDLE
• ONE PIECE NEEDLE
• Sharp beveled tip
• Guidewire introduced directly through it
• Both arterial and venous access
• TWO PIECE NEEDLE
• Blunt tip with sharp stylus
• Less vascular injury with the blunt tip
• Guide wire inserted after removing the stylet
• Usually for arterial puncture
MC needle Size – 19/18 G in diameter and 21/4 - 5 inches in
length

14. TOOLS
• MICROACCESS SYSTEMS
• Small access needle – made bigger with
plastic introducer
• 21 G needle for access
• 0.018 inch guide wire
• 4F or 5F dilator followed by 3F
• Arterial and Venous

15. TOOLS
• GUIDEWIRE(Safety Guidewire)
• Thickness same or smaller than the size of the tip
of catheter or device that slides over it
• Too small size can create gap that can prevent
smooth movt over the guidewire
• MC design
• Central stiff core
• Wounded by small wire – Dec area of contact
b/w tissue and guidewire
• Small safety wire within welded to outer wrap in
both ends – prevents unwinding if it breaks
• Average Length : 145-160cm
• Exchange length guide wire - 260-300cm

16. TOOLS
• Stiff guidewire – introducing catheter and devices
• Flexible : negotiating tortuous /diseased vessels
• Movable core guidewire – adjust flexibility
• Mandril Guidewire : Only wrapped at the tip- micro guidewire
and extra rigid large diameter guidewire
• Tip Deflecting guidewire : manipulate the radius of tip
• Hydrophilic coated guide wire
• Coated central core
• Reduces friction
• Needs to be moist always

18. TOOLS
• DILATOR
• Plastic catheter
• Purpose: Spread the soft tissues and
vessel wall to facilitate catheter entry
• Sequential (1F-2F)dilatation to prevent
trauma
• Usually 18G access needle uses 5F
initially
• >50% diameter of the vessel diameter
– obviates manual compression
Kaufman JA, Lee MJ, editors. Vascular and
interventional radiology: the requisites. St. Louis:
Mosby; 2004.

19. VASCULAR
CATHETER
GUIDE
(6-8F)
DIAGNOSTIC
(4F-6F)
SELECTIVE
FLUSH(non
selective)

20. CATHETER
HEAD
SIMPLE COMPLEX
REVERSE
CURVE
DOUBLE
CURVE

22. TOOLS
• CATHETER
• Made of polyurethane,
polyethylene, Teflon, or nylon
• Catheters vary based on their
intended use
• Non selective aortography – Thick
walled with pig tail tip , multiple
side holes
• Selective catheter : Thin walled
with tapered tip , single end hole
and metal /plastic strand BRAID tip
• Measurements
• Outer size – in F
• Diameter of end hole - in G
• Name
• based on shape : pigtail , cobra,
hockey stick
• Designer : Simmons, Berensterin ,
Rosch

24. CATHETER SELECTION
Select catheter that points in the general direction we
wish to travel
A. Tip length: Increased length offers more stability
with compromised maneuverability
B. Primary curve: based on angle of the target vessel
from the parent artery
C. Secondary curve: Based on the width of the
parent vessel
D. Tertiary curve: Based on normal curvature of the
parent vessel
E. Length
• Shorter: 50cm- C/l iliac artery injection
• Mid: 65cm – renal , celiac, mesenteric
• Longer:100-125cm – abdominal aorta
ANGIOGRAPHIC CATHETERS: A COMPREHENSIVE REVIEW FOR THE
INTERVENTIONALIST IN-TRAINING , R Freed; A Urdaneta; R Darflinger; G Vatakencherry

25. TOOLS
FLUSH CATHETER SELEECTIVE CATHETER
Allow high flow injections into the aorta and IVC
Unifom dispersal of contrast media via multiple side
holes
Tip designed to help center the shaft In the vessel and
prevent engagement and injecton into a branch vessel
Have rotational stiffness to seek a vessel orifice but
with enough flexibility to pass the catheter far into the
vessel
Shaped in a particular way to seek intended vessel
ostium

26. TOOLS
COMPLEX CATHETER
• The shape of these catheters must be reformed inside the body after
insertion over a guidewire
• Any catheter will resume its original shape, provided there is
sufficient space within the vessel lumen and memory in the catheter
material.
• Some catheter shapes cannot re-form spontaneously in a blood
vessel, particularly the larger recurved designs like the Simmons.

27. AORTIC SPIN TECHNIQUE

28. BRANCH TECHNIQUE(Simmons )

29. TOOLS
SELECTVE CATHETERISATION
Choosing a selective catheter shape:
Angled catheter(a) when angle of axis
of branch vessel from aortic axis is
low.
Curved catheter(b) (e.g., cobra-2,
celiac) when angle of axis of branch
vessel is between 60 and 120
degrees.
Recurved catheter(c) (e.g., SOS,
Simmons) when angle of axis of
branch vessel from aorta is great.

30. TOOLS
HOW TO USE A COBRA CATHETER
1. Catheter advanced to position proximal
to branch over guidewire, then pulled
down(arrow).
2. Catheter tip engages orifice of branch.
Gentle injection of contrast agent to
confirmed location.
3. Soft-tipped selective guidewire has
been advanced into branch.
4. Guidewire is held firmly, and catheter is
advanced to selective position.

31. TOOLS
HOW TO USE A SIMMONS CATHETER:
1. Catheter is positioned above
branch vessel with at least 1 cm of
floppy straight guidewire beyond
catheter tip.
2. Catheter is gently pulled
down (arrow)until guidewire and tip
engage orifice of branch.
3. Continued gentle traction results in
deeper placement of catheter tip.
4. To deselect branch, push catheter
back into aorta (reverse steps 1-3).

32. TOOLS
MICROCATHETER
• Designed to fit coaxially within the
lumen of a standard angiographic
catheter
• Typically 2F to 3F in diameter, with
0.010- to 0.027-inch inner lumens.
• Designed to reach far beyond standard
catheters in small or tortuous vessels
like in Bronchial arteries, GI bleeds,
Uterine Fibroid embolization etc

33. TOOLS

34. TOOLS
• When using a microcatheter, a standard angiographic catheter that
accepts a 0.038- or 0.035-inch guidewire is first placed securely in a
proximal position in the blood vessel.
• The microcatheter is then inserted through the outer catheter and
advanced in conjunction with a specially designed 0.010- to 0.025-
inch guidewire through the standard catheter lumen.
• Once a superselective position has been attained with the
microcatheter, a variety of procedures can be performed
• Contrast and flush solutions are most easily injected through these
catheters with 3-mL or smaller Luer-Lok syringes.

35. MICROCATHETER

36. TOOLS
GUIDING CATHETER
• Help position and stabilize standard
catheters.
• Larger lumen and prefixed shape to
accept standard sized catheters and
devices
• Ex : Renal artery arising from tortuous
and aneurysmal abdominal aorta.
This can guide the standard catheter
through the large lumen of guiding
catheter

41. TOOLS
SHEATHS
• Atraumatic vascular access
• Simplify catheter exchange through a single access
• Maintain guidewire position
• Prevent bleeding in the puncture site

42. SHEATH
• Open at one end with capped hemostatic valve in the other

44. TOOLS
CONTRAST AGENTS
• Should have excellent radioopacity , mixes well with blood, easy to
use, inexpensive and does not harm the patient

45. TOOLS
ADVERSE REACTIONS OF THE CONTRAST
• Anaphlyaxis

46. TOOLS
 CONTRAST INDUCED RENAL FAILURE
 MC in pts with DM , preexisting renal failure (Cr > 1.5mg/dl)
 AKIN definition of AKI (w/in 48 hrs)
 >0.3mg/dl inc in Cr
 50% inc from baseline Cr
 Urine output reduced to ≤0.5 mL/kg/hour for at least 6 hours

47. TOOLS
ALTERNATIVE CONTRASTS
• CO2
• Gd chelates
• Can cause Nephrogenic fibrosing sclerosis (CrCl - < 60mg/dl)

48. DIGITAL SUBTRACTION ANGIOGRAPHY
The acquisition of digital fluoroscopic
images combined with injection of contrast
material and real-time subtraction of pre-
and postcontrast images to perform
examinations is referred to as digital
subtraction angiography

49. DIGITAL SUBTRACTION ANGIOGRAPHY
• The Portuguese neurologist Egas Moniz,( Nobel Prize winner 1949), in
1927developed the technique of contrast x-ray cerebral angiography
to diagnose diseases, such as tumors and arteriovenous
malformations
• The idea of subtraction images was first proposed by the Dutch
radiologist Ziedses des Plantes in the 1935, when he was able to
produce subtracted images using plain films

50. DIGITAL SUBTRACTION ANGIOGRAPHY
PRINCIPLE
• The scout film shows the
structural details of and the
adjacent soft tissue.
• Angiogram film shows exactly the
same anatomic details, if the
patient does not move, plus the
opacified blood vessels.
• If all the information in the scout
film could be subtracted from the
angiogram film, only the
opacified vessel pattern would
remain visible.

51. DIGITAL SUBTRACTION ANGIOGRAPHY
ROAD MAPPING
• It is useful for placement of
catheters and wires in complex
and small vasculature
• DSA sequence performed
• Frame with maximum vessel
opacification is identified (Road
map Mask)
• This is subtracted from
subsequent live fluoroscopic
images
• Thus real time subtracted
fluoroscopic images are overlaid
on a static image of the
vasculature

52. INTRA PROCEDURE

53. INTRAPROCEDURE PATIENT CARE
PATIENT MONITORING
• Baseline vital signs to be recorded
• Continuous cardiac monitoring , pulse oximetry , BP measurement
every 5- 10 mins based on the condition
• Oxygen via face mask or nasal cannula

54. INTRAPROCEDURE CARE
FLUID MANAGEMENT
• Based on pre existing conditons
• General rule : 1ml/kg/hr fluids
• Foleys – For long hour procedures

55. INTRAPROCEDURE CARE
SEDATION AND ANALGESIA
• Goals: Relief of pain , anxiety, partial amnesia
• Moderate sedation : Calm and drowsy but responds to verbal
commands , protects his airway and reflexes
• Deep Sedation/GA : Protective reflexes are lost, needs anaesthetist
• Drugs : Midaz+ Fental
• Midax: 0.5-2.0mg IV , 2-4mins onset , 45-60 mins action
• Fentanyl : time of onset same as Midaz, 25-50 mic
• Additonal dose every 3 – 10 mins to maintain analgesia and sedn

56. INTRAPROCEDURE CARE

57. INTRAPROCEDURAL CARE
INFECTIOUS DISEASE PREVENTION
• Risk of transmission of blood borne pathogens from pt to doctor is
small ,but vice-versa is real
• Universal precautions to be followed
• Surgical gowns , mask , protective eyewear and two pairs of gloves
• Secure place for sharp objects on the interventional table
• Needle prick if any to be reported ASAP and start prophylaxis within 1 HOUR
of exposure

58. INTRAPROCEDURAL CARE
ANTIBIOTIC PROPHYLAXIS
• Sterile procedures
• Shave off the hair at the site prior to procedure
• Antibiotic prophylaxis is not necessary for the majority of patients
undergoing diagnostic angiography.
• Exceptions: Asplenic and neutropenic pts

59. INTRAPROCEDURAL CARE - ANTICOAGULATION
• Rarely required in diagnostic peripheral angiography
• Unless catheter impedes flow in diseased or small vessel
• Some give in Carotid angiography for occlusive disease
• Heparin 3000-5000U bolus IV f/b 1000U each hour
• Effect monitored by activated clotting time(>250s)
• Heparin antidote : Protamine - 10mg /1000HU IV slow bolus

60. INTRAPROCEDURAL CARE
BLOOD PRESSURE CONTROL
• SBP< 170mmhg – to prevent cardiac ischemia and hemostasis
• Most pts returns to normal post sedation/analgesia

61. INTRAPROCEDURAL CARE
PEDIATRIC PATIENTS
• GA
• <15kg pts: Routine heparinization(75-100U/kg)
• Inc risk of catheter induced spam
• CFA is preferred access
• Temp control during long procedures for infants
• Non ionic contrast (not more than >5ml/kg for short procedures)
• Hand injection if wt<10kg

62. INTRAPROCEDURE
ARTERIAL ACCESS
• Position the patient that provides the easiest and direct access to the
puncture site
Guidelines in selecting an access site
• Area of interest must be approachable from the access artery
• Access artery should be large enough to accommodate devices
• No critical organs between the skin and the artery
• Puncture over the bone – facilitate compression post procedure
• Pulse should be readily palpable
• Overlying skin should be free of infections/scar

63. VASCULAR ACCESS

64. COMPLICATIONS
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457.
https://doi.org/10.1007/s00270-010-9820-3

65. COMPLICATIONS
HEMATOMA
• Signs – hypotension , tachycardia , loss of I/L distal pulse , faintness ,
confusion , agitation and abd pain
• Abdominal CT – to look for hematoma
• Mark the hematoma with pen for change in size assessment
• Endovascular procedure : stent-graft placement (>1mm diameter of
vessel for adequate anchorage )
• Completion angiogram to confirm the success
• Surgical evacuation If massive
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-010-9820-3

66. COMPLICATION
ARTERIAL CLOSURE DEVICES
• Reduce time to hemostasis and ambulation
• Useful in
• Anticoagulated pts
• Larger sheath sizes
• Poorly compliant pts
• Three main types
• Collagen based
• Suture based
• External clip/staple

67. COMPLICATION – ARTERIAL CLOSURE DEVICE

68. Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-010-
9820-3

69. MANAGEMENT OF COMPLICATIONS
PSEUDOANEURYSMS
• One of the most common complication requiring intervention
• Surgical repair has high complication rates like inadequate wound
healing , femoral neuralgia and lymphatic leak
• USG guided procedure is often used
• USG guided compression(size < 1cm)
• USG guided thrombin injection

70. COMPLICATIONS
USG GUIDED COMPRESSION

71. COMPLICATIONS
USG guided Thrombin Injection
• Standard of care
• Patient preparation
• Local analgesia
• Preperation of the thrombin solution – Bovine or human thrombin in 100-
1000IU/ml mixed in NS
• ALT : Thrombin kit – 2ml Cacl2 + 1000IU thrombin + 8 ml saline in 10 ml syringe
• 21 or 22G needle for insertion into the pseudoaneurysm
• Injection rate : increments of 0.1-0.2ml
• Recheck after 10 mins of injection for complete thrombosis
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-
010-9820-3

72. COMPLICATIONS
• Post procedure management
• Check foot pulse
• 2 hrs bed rest
• F/u scan in 24 hrs
• Inc failure rate if size > 6cm
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-010-9820-3

73. COMPLICATION
AV FISTULA
• Surgical repair usually necessary
• Coil embolization if the tract is of sufficient length
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-010-
9820-3

74. COMPLICATIONS
ARTERIAL DISSECTION
• Focal and non flow limiting – conservative
• Flow limiting – prolonged endovascular balloon inflation across the
dissection to approximate the dissected intima with media
• If extending into the iliac vessel - use self expanding stents
ARTERIAL THROMBOSIS
• Nonocclusive – systemic anticoagulation
• Occlusive – Surgical thrombectomy
• Non surgical candidate – second access site from c/l site and
pharmacomechanical (rt-PA and urokinase)thrombolysis
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-010-
9820-3

75. COMPLICATIONS
Tsetis, D. Cardiovasc Intervent Radiol (2010) 33: 457. https://doi.org/10.1007/s00270-010-
9820-3

76. INTRAPROCEDURE PATIENT CARE
TREATMENT OF ADVERSE EVENTS AND REACTION
• Hypoxia and respiratory depression – Supplemental Oxygen ,
withhold sedative, naloxone/Flumazenil as antidote
• Nausea vomiting – Antiemetics
• Vasovagal Reaction – Atropine 0.5-2.5mg
• HTN – IV labetalol 5-10 mg ;upto 20mg
• Contrast reaction- Oxygen , IV fluids , 0.1mg epi in 1: 10000 every 3
mins

77. INTRAPROCEDURE PATIENT CARE
TREATMENT OF ADVERSE EVENTS AND REACTION
Hypoglycemia – 5 OR 10D infusion
Seizure – Diazepam 5-10mg

78. POST PROCEDURE

79. POSTPROCEDURE PATIENT CARE
CATHETER REMOVAL
• Usually withdrawn immediately after the procedure
• Before removing
• Check the access site
• Check distal pulses
• Control HTN
• Apply pressure for 10-20 mins if minor bleeding persist

80. POSTPROCEDURE PATIENT CARE
PATIENT MONITORING
• Check the access site and distal pulses
• Every 15 mins for 1 hour
• Every 30 mins for next hour
• Then hourly
• Post femoral or brachial arteriography – 4 to 6 hrs observation
• Post brachial or femoral venography – 2 to 4 hrs period

81. POSTPROCEDURE PATIENT CARE
ORDERS
• ACTIVITY: bed rest till monitoring period is complete
• PAIN CONTROL: Oral and parentral opioids(morphine,fentanyl)
• DIET: Liquids or soft solid meal
• HYDRATION: If IV contrast given , continue IV hydration in post op
period , maintain it till pt recovers from moderate sedation
• RED FLAG SIGNS : ask the patient to watch for cold extremities,
painful puncture site , obvious hematoma or bleeding , absence of
urination in the subsequent 24 hrs of discharge

82. POSTPROCEDURE PATIENT CARE
DISCHARGE CRITERIA
• Stable vitals with no respiratory depression
• Alert and oriented
• Able to drink , void and ambulate
• Minimal residual pain
• Minimal nausea
• No bleeding at nausea site
Follow up appointment to be scheduled to evaluate the results of
therapy , identify complications and need for further intervention

83. VASCULAR INTERVENTIONS

84. VASCULAR INTERVENTION TECHNIQUES
VASCULAR
INTERVENTION
IMPROVING
LUMEN
•1.Balloon angioplasty
•2.Embolic protection
devices
•3.Stents and stent-grafts
•4.Debuking atheromas
•5.Pharmacologic
thrombolysis
•6.Mechanical
thrombectomy
OCCLUDING
LUMEN
1.Embolisation
2.Endovascular ablation
3.Vasoconstriction

85. VASCULAR INTERVENTION TECHNIQUES
BALLOON ANGIOPLASTY(PTA)
• First line for stenosis Rx
Mechanism Of Action
• Inflation causes desquamation of endothelial cells ,splitting of plaque
and stretching of intima
• Platelets and fibrin cover the denuded area
• Rendothelialisation of the vessels occur in few weeks
Patient Selection
• Hemodynamically significant stenosis
• Clinical improvement expected

86. VASCULAR INTERVENTION TECHNIQUES - BALLOON ANGIOPLASTY(PTA)
Unsafe Conditions /Less Sensitive
• Stenosis adjoining an aneurysm (owing to higher risk for rupture)
• Bulky, polypoid atherosclerotic plaque (owing to higherrisk for distal
embolization)
• Diffuse disease
• Long-segment stenosis or occlusion
• No pain sensation

87. VASCULAR INTERVENTION TECHNIQUES - BALLOON ANGIOPLASTY(PTA)
Technique
• Shortest balloon yet covering the lesion
• Slight overdilation required
• Atherosclerotic plaques: 5-10atm ;Venous and graft stenosis: 18-
24atm
• Pharmacologic adjuncts
• Aspirin: Prevent postangioplasty thrombosis
• Preprocedural and post procedural
• Heparin: Given before crossing the obstruction, continued throughout the
procedure
• Vasodilators : Prevent or relieve angioplasty induced vasospasm

88. VASCULAR INTERVENTION TECHNIQUES - BALLOON ANGIOPLASTY(PTA)

89. VASCULAR INTERVENTION TECHNIQUES - BALLOON ANGIOPLASTY(PTA)
Treatment is successful if
• Less than 30% stenosis
• Minimal pressure gradient (arterial <5-10mmhg)
Complication
• Vessel occlusion – IV bolus heparin or intraarterial vasodilator
• Distal embolization- anticoagulation,percutaneous aspiration or
surgical embolectomy

90. VASCULAR INTERVENTION TECHNIQUES - BALLOON ANGIOPLASTY(PTA)
CUTTING BALLOONS
• Microthin longitudinal blades
along the surface
• Treat stenosis resistant to
high pressure balloons

91. VASCULAR INTERVENTION TECHNIQUES
EMBOLIC PROTECTION DEVICES
• Embolisation of plaque elements – Cholesterol embolization
• Macroembolisation or microembolization based on size
3 basic types
• Distal filter(80-200mic particles filtered)
• Distal occlusion balloons
• Proximal occlusion balloons

92. VASCULAR INTERVENTION TECHNIQUES

93. VASCULAR INTERVENTION TECHNIQUES
Stents
Covered/
Stent Graft
Uncovered
Self
Expandable
Balloon
Expandable
Open celled Closed celled

94. VASCULAR INTERVENTION TECHNIQUES
UNCOVERED METALLIC STENTS
• Maintain lumen patency by
compressing the atherosclerotic
disease
• Prevent remodeling and elastic recoil
COVERED STENTS
• Metallic devices with ‘synthetic graft
material ‘layered luminal surface
• Covering is by polyethylene
terephthalate , polytetrafluoroethylene
or dacron
• IT prevents neointimal proliferation in
the stented segment
• Used in TIPS creation , vascular rupture
, AV fistulas , malignant GI obstructions

95. VASCULAR INTERVENTION TECHNIQUES
General Principles
• Larger and longer than the diseased segment to prevent stent
migration
• In arteries – always use sheath and guiding catheter to protect the
stent and vessel during the transit
• Cover entire obstruction. Residual disease at mouth can cause
thrombosis or stenosis

96. VASCULAR INTERVENTION TECHNIQUES
Patient Selection
• Primary treatment of coronary, iliac, and renal artery obstructions
• Immediate or long-term failures of balloon angioplasty (arterial and
venous)
• Complications of angioplasty or catheterization procedures (e.g.,
dissection)
Properties
• Made of stainless steel, nitinol and Elgiloy

97. VASCULAR INTERVENTION TECHNIQUES- METALLIC STENTS
CONTRAINDICATIONS
• Stenosis resistant to balloon angioplasty (absolute)
• Arterial rupture after angioplasty (absolute)
• Adjacent to an aneurysm (relative)
• Impaired pain sensation (relative)

98. VASCULAR INTERVENTION TECHNIQUES
Balloon expanding: Deployed by inflating an
balloon
• Resist vessel wall recoil
• Will not reexpand spontaneously if resistance is
temporarily overcome
Self Expanding: Deployed by releasing a
constraining mechanism
• Thermal memory which expands in body
temperature and not room temp
• Attempt to reach a predetermined size , reexpand
spontaneously if compressed
• Used in superficial location like SFA and cervical
carotid

100. VASCULAR INTERVENTION TECHNIQUES
Open celled and close
celled: open celled are more
flexible while closed are
more rigid

101. VASCULAR INTERVENTION TECHNIQUES
DRUG ELUTING STENT
• Prevent restenosis after recanalization
• Smooth muscle cell proliferation inhibitors are incorporated to the
stent

102. VASCULAR INTERVENTION TECHNIQUES

103. VASCULAR INTERVENTION TECHNIQUES

104. VASCULAR INTERVENTION TECHNIQUES
DEBULKING ATHEROMA
• Changes the volume of the preexisting disease(not done by stents)
DEBULKER
Cutting blade
Remove sufficient
volume
Additional Inx not
required
Drill and Laser
Channel same as the
device dimater
Additional Inx required

105. ROTAREX®S by Straub Medical AG

106. VASCULAR INTERVENTION TECHNIQUES- Debulking
USES
• Fibrotic lesion
• HPE of the tissue
Disadvantage
• Heavily calcified plaque
• Severely tortuous vessels

107. VASCULAR INTERVENTION TECHNIQUES
ENZYMATIC THROMBOLYSIS
• Used in Rx of acute occlusion
• Agents used : Streptokinase, urokinase,
alteplase t-PA, reteplase
• Chronic thrombus less likely to lysed.
• Inability to cross the thrombus with guide
wire is a rough predictor of failed lysis
• MC disadv: Bleeding

108. VASCULAR INTERVENTION TECHNIQUES

109. VASCULAR INTERVENTION TECHNIQUES

110. VASCULAR INTERVENTION TECHNIQUES
TECHNIQUE
Drip infusion
• Continuous infusion of low dose thrombolytic(rTPA 0.5mg/hr)
• Repeat angiography every 3-6 hours
• Catheter manipulated to the thrombus and look for improvement in
angiographic appearance(max 36-48hrs)
• Discontinued if no improvement in 12 hrs

111. VASCULAR INTERVENTION TECHNIQUES

112. VASCULAR INTERVENTION TECHNIQUES
• Pulse spray technique(Angiojet®)

113. VASCULAR INTERVENTION TECHNIQUES
COMPLICATION MANAGEMENT
Hemorrhage Terminate infusion
Stroke Terminate infusion and appropriate imaging
Puncture site hematoma External compression , if unsuccessful , terminate
Distal embolization Aspiration thrombectomy , redirecting aspiaration
Reperfusion syndrome
Pericatheter thromboisV

114. VASCULAR INTERVENTION TECHNIQUES
PHARMACOMECHANICAL THROMBOLYSIS
• Thrombolytic agent with a device disrupting thrombus
• Principle : Fragment the thrombus , increased surface area for the
drug to act
• 30-40% pts require additional clearing of thrombus by catheter
directed thrombolysis
• Ex : Angiojet , EKOS (ultrasound + lytic drug)

115. VASCULAR INTERVENTION TECHNIQUES –EKOS ®

116. VASCULAR INTERVENTION TECHNIQUES
VASODILATORS

117. VASCULAR INTERVENTION TECHNIQUES
DECREASING BLOOD FLOW THROUGH THE VESSEL

118. VASCULAR INTERVENTION TECHNIQUES
A Case-Based Approach to Common Embolization Agents Used in Vascular Interventional Radiology
Avinash Medsinge, Albert Zajko, Philip Orons, Nikhil Amesur, and Ernesto Santos
American Journal of Roentgenology 2014 203:4, 699-708

119. Lubarsky, M., Ray, C. E., & Funaki,
B. (2009). Embolization Agents—
Which One Should Be Used
When? Part 1: Large-Vessel
Embolization. Seminars in
Interventional Radiology, 26(4),
352–357. http://doi.org/10.1055/s-
0029-1242206

120. VASCULAR INTERVENTION TECHNIQUES

121. VASCULAR INTERVENTION TECHNIQUES
ENDOLUMINAL THERMAL ABLATION
• Rx of GSV and LSV
• Laser and RF probe used
• Laser : heat the blood , coagulate it .some destroy the endothelium
too
• RF probe: heat the vessel wall and the blood , denatures the vessel
wall , edema of the vessel and luminal narrowing

122. VASCULAR INTERVENTION TECHNIQUES
VASOCONSTRICTOR DRUGS
• When temporary decrease of blood required
• Ex: GI bleeding from diverticulosis
• Agents : Vasopressin – 0.4U/min(past) ,Epinephrine – 2mic/ml