Dr. Anil Meetei presented on endovascular surgery and its various procedures and techniques. Endovascular surgery involves minimally invasive procedures using catheters and instruments inserted into blood vessels. Some key procedures discussed included balloon angioplasty, stenting, atherectomy to remove plaque, thrombolysis to treat clots, and filters to prevent pulmonary embolism. Factors such as device sizing, access points, imaging, and complications were also reviewed.

1. Presenter: Dr Anil Meetei
Moderator: Dr Th Chito
Asst prof, CTVS

2. Endovascular surgery
Endovascular surgery is a form of minimally invasive
surgery/procedures for imaging the circulation or for
treating vascular disorders from within the circulation,
through catheters/miniature instruments inserted
percutaneously into the blood vessels

3. Scope of endovascular therapy
 Baloon angioplasty
 Endovascular cryotherapy
 Stenting
 Angioscopy /intravascular ultrasound
 Atherectomy
 Thromb0embolectomy /intraarterial thrombolysis
 Embolization
 Endovascular aneurysm repair (EVAR)
 Endovenous laser ablation (EVLA)
 Endovascular RFA
 Transcatheter aortic valve implantation (TAVI)
 Percutaneous mitral valve repair

4.  Basic instruments
 Needles
 Guidewires
 Catheters
 Sheaths

5. Endovascular device sizing
 DEVICE MEASUREMENT UNIT
1. Entry needle outer diameter gauge
2. Guide wire outer diameter inch
3. Sheath inner diameter french
4. Guiding outer diameter french
catheter
5. diagnostic outer diameter french
catheter

6.  Common interventions
 Balloons
 Stents
 Stent grafts
 Filters
 Thrombolytics
 Closure devices
 IVUS

8.  Contrast media
 Ionic
 Non ionic

9. Contrast agents
Iso osmolar-iodixanol, iotrolan(non ionic)
Low osmolar
Ionic dimer-meglumine ioxaglate
Non ionic monomer- iopamidol, iohexol(omnipaque),
ioversol, iopromide
High osmolar
Ionic monomer- meglumine diatrzoate(hypaque,
gastrograffin, urograffin)

10.  ACCESS
 Common femoral artery, popliteal, tibial, axillary,
brachial, radial, carotid, subclavian
 Bone/bony prominence beneath the artery
 Avoid diseased areas
 Away from side brances, bifurcations, or crossing veins
 External skin markings, ultrasound guided, fluoroscopy

11.  Puncture site: common femoral artery on the medial
3rd of femoral head 1-2 cm below the inguinal ligament
 A puncture site below the ligament cannot be
compressed and could result in a large pelvic
hemorrhage
 Puncture of the SFA must be avoided to prevent
pseudo-aneurysm and hematoma correlate to the
inefficacy of the compression

12.  ACCESS
 1. Retrograde-relatively large diameter, ease of
compression, options for image guided puncture
 2. Antegrade- commonly used for infrageniculate
interventions, aortic bifurcations that are prohibitive
to a contralateral retrograde CFA access and for
chronic total occlusions
 straight line approach- easy maneuvering

13.  ACCESS
 1. Single wall Puncture
 2. Double wall Puncture

14. Guidewires
 • Composite construction
 • Materials
 – Stainless Steel
 – Nitinol
 – Jacketed Composite
 Hydrophilic/hydrophobic

15.  • Core
 • Stainless Steel
– Used for support
– Stiffness varies based on taper / diameter of core
 • Nitinol
– Used for it’s flexibility, memory and kink resistance
 • Tip
 • Platinum / Gold
– Provides radiopacity
– Atraumatic
– Ribbon formed for shaping tip

16. Grind & tip performance
 • Stiff
 • Intermediate
 • Floppy

18. Sheaths
 Sheaths are hemostatic conduits inserted into the
vessel. They allow passage of guidewires, catheters and
interventional devices.
 Hemostatic valve at the tip and a side port for
aspiration/administration of drugs
 Helps minimize local trauma to the vessel from
repeated exchanges as well as decrease blood loss and
hematoma formation

20. Sheaths
 Peripheral and coronary sheaths have a universal color code
 Universal color coding
4 Fr = red
5 Fr = gray
6 Fr = green
7 Fr = orange
8 Fr = blue
9 Fr = black
10 Fr = violet
11 Fr = yellow
 Sheaths are measured inner diameter in french size (1fr =
.33mm)

21. catheters
• Guide catheter
• Diagnostic catheter
• Non selective
• Selective
• Crossing

22. Endovascular surgery
 Typically performed under LA
 Less invasive
 Quicker return to function
 Durability compared to open surgical options
 Highly skilled operator
 Endovascular suite with fluoroscopy
 Costly

23. Complications of endovascular
procedures
 Systemic, access site, or wire/catheter related complications
 Contrast induced nephropathy
 Increase age(>75 yrs), CRF(creatinine>1.5mg/dl), heart failure, DM,
preprocedural hypotension, anaemia , ionic contrast medium
 Proper hydration, Minimum contrast dose
 Access site-MC
 Hematoma(3%), thrombosis(2%), bleeding, AVF, pseudoaneurysm
 Hematoma-reversal of anticoagulation, vol resuscitation,
hematoma evacuation
 Catheter related-
 dissection, distal embolization, perforation

24. Seldinger technique
 Sven Ivar Seldinger- Swedish radiologist (1953)
 The Seldinger technique is a medical procedure to obtain safe access
to blood vessels
 The desired vessel is punctured with a sharp hollow needle called a
trocar, with ultrasound guidance .
 Guidewire is then advanced through the lumen of the trocar, and the
trocar is withdrawn. A "sheath" or blunt cannula is passed over the
guidewire into the cavity or vessel. After passing a sheath or tube, the
guidewire is withdrawn.
 A sheath can be used to introduce catheters or other devices to perform
endoluminal procedures.
 Fluoroscopy is used to confirm the position of the catheter and to
manoeuvre it to the desired location. Injection of radiocontrast may be
used to visualize organs.
 Upon completion of the desired procedure, the sheath is withdrawn. a
sealing device may be used to close the hole made by the procedure.

26. Balloon angioplasty
 Fogarthy (1963)- used endovascular catheter for extraction of arterial
emboli and thrombi
 Dotter and Judkins (1964)-transluminal treatment of arterial stenosis
 Types
 Percutaneous transluminal angioplasty (PTA)
 Subintimal angioplasty
 PTA with stenting

27. Technique
 Shortest distance from the access vessel to the target vessel
 Retrograde right common femoral artery access
 Tibial occlusive disease-I/L anterior common femoral access
 Heparinization-5000 IU as standard bolus dose after arterial
access. 1000 IU/L heparinized saline for flushing
 Arteriography to identify the lesion and severity
 Lesion crossed and contrast injected
 Balloon diameter and length carefully chosen
 IVUS/CTA- for sizing the lesion
 Balloon inflated for 1 min, withrawn after deflating
 Contrast injection to assess the PTA result

28.  Iliac and femoro popliteal segments. Less successful
for below knee narrowing
 Coronary arteries
 Complications- failure, hematoma formation,
bleeding, thrombosis, distal embolisation

30. Subintimal angioplasty
 Bolia et al (1989)-for chronic total occlusions
 Creating an intentional subintimal plane across the occlusion
with a guidewire and wire redirected back into the true lumen
 Iliac and femoropopliteal occlusions- successful in highly
calcified lesions, long occlusions(>15 cm)
 Higher patency rates were observed in limbs treated for
claudication than limbs treated for chronic total occlusions
and criticallimb ischaemia
 12 month patency <70%
 Mean increase in ABI is 0.3
 Technical failure rate ~26%- mostly due to inability to reenter
the true lumen distal to the occlusion(70%)

32.  Types of balloon
 Complaint balloon
 Non complaint balloon
Complaint balloon
–expand in the direction of least resistance
- more potential for arterial injury
-potentially treat vessels of varying diameter
Non complaint balloon
-polyolefin copolymer/polyethylene/nylon reinforcement
-provide higher uniform dilating force –highly calcific
lesions

33.  Cutting balloon angioplasty-
 Ballon loaded with metal atherotome or microsurgical blades
 Designed to create controlled incisions into the thrombus
and dilate the vessel with less force than conventional balloon
angioplasty
 CBA- reasonable option for infrainguinal vein graft stenosis
-superior results to PTA
-more chance of perforation

34.  Endovascular cryotherapy
 Balloon catheter inflated with nitrous oxide delivering cold
thermal energy(-10 C) to the arterial wall.
 Alters healing response after angioplasty, principally inducing
smooth muscle cell apoptosis rather than necrosis, thus
reducing myointimal hyperplasia
 CLIMB study
-initial success rate 95%
-stents required in 17%
-primary patency at 12 months @56% and comparible with
those achieved with conventional PTA
-recommended for lesions >55mm

35.  Drug coated balloons(DCBs)
 Substantial amounts of antiproliferative agents were delivered
to the arterial wall during short periods of balloon inflation.
 For prevention of re stenosis and myointimal hyperplasia
 Paclitaxel coated balloons deliver drug during balloon
inflation( superficial femoral artery)
 Drug eluting stents (DES)
-coronary circulation/infrainguinal arterial occlusive disease
-Sirolimus/paclitaxel-inhibits smooth muscle cell proliferation

36. Stenting
 Stent-comes from 19th century London dentist-
Charles Stent
 Charles Dotter (1983)-nitinol stents were first used
 Palmaz et al (1985)-balloon expandable stent
 Two types
 Bare metal stent
 Stent graft
 Two types based on deployment method
 Balloon expandable
 Self expanding

38. Balloon expandable Self expandable
 High radial/longitudinal
force
 Precise placement
 Further expansion with larger
balloons
 Radiopaque
 Short length
 Prone to crushing
 Flexibility
 Long stent lengths
 Continued radial force if
oversized
 Crush resistant
 Ability to clamp the stent
 Low radial force
 Inaccurate/less precise
placement
 Limited radiopacity

39. Angioscopy
 Used for visualizing the interior of blood vessels
 Arterial embolism, adjunctive procedure during
vascular bypass to visualize valves within venous
conduit
 Visualize stents in catheterization lab

40. Intravascular ultrasound
 Uses miniature ultrasound probe attached to distal
end of an intravascular catheter(uses 20-40MHz)
 Useful with unreliable angiographic images-lumen of
ostial lesions, or in regions with multiple overlapping
arterial segments
 Advantages over angiography-measures atheroma
hidden within the vessel wall, identifies vulnerable
plaque. Measures the effect of different treatment
strategies for changing the evolution of the
atherosclerosis disease process

42. Atherectomy
 Endovascular atherectomy allows the physical removal of
atherosclerotic plaque material from the blood vessel, with a
theoretical benefit of removing the obstructing plaque rather
than mere displacing it, as with angioplasty and stenting
 Open atherectomy remains the gold standard. Endovascular
atherectomy is useful in vessels with difficult access
 Excisional atherectomy catheters remove and collect the
atheroma, whereas ablative device fragment the atheroma into
small particles
 3 types of atherectomy devices
 Directional
 Rotational
 Laser

43.  Directional atherectomy
 Best suited for discrete calcified atherosclerotic lesions
of infrainguinal arteries. Not used for chronic total
occlusion
 Silverhawk plaque excision system-the device is
advanced under fluoroscopic guidance to the proximal
portion of the target lesion, where a carbide cutter excise
the atheroma and traps it within the nose come of the
device; once filled with plaque the device is removed,
the nose cone is emptied, and the device is reintroduced
over a guidewire

45.  Rotational atherectomy utilizes a rotating burr or
blade to excise plaque, whose microparticles are either
aspirated or allowed to embolize distally
 Jetstream – device success rate 99%.TLR -15% and 26%
at 6 and 12 months respectively; restonosis 38% at 1yr
 May cause vasospasm-calcium channel blockers/
nitroglycerine

46.  Laser atherectomy
 Utilized in CTOs, both de novo or in in stent thrombosis
 Cold tip laser that delivers burst of ultraviolet xenon
energy in short pulse duration.
 Key features is the ability to debulk tissue without
damaging surrounding tissue, minimizing restenosis
COMPLICATIONS
-embolism 1.3%

47. Thromboembolectomy
 Management of acute thrombotic or embolic arterial
occlusions
 Fogarty catheter
 Purely percutaneous thrombolectomy
 Aspiration
 Rheolytic devices
 Mechanical fragmentation with or without
pharmacologic lysis

49.  Simple aspiration either via a large sheath or guide
catheter work well in small vessels< 6mm
 Rheolytic devices utilize jets of saline, directed from
the tip of the catheter back toward its more proximal
portion, to create a venturi effect, resulting in clot lysis
and aspiration.
 Arterial access is ideally made antegrade to the area of
thrombotic occlusion. Lower extremity lesions are
approached through contralateral femoral artery

51. Inferior vena cava filter
 Prevent life threatening pulmonary emboli
 Retrievable/ permanent
 Indications
 DVT/PE with contraindications to anticoagulation
 Recurrent VTE despite adequate anticoagulation
 Poor patient compliance(INR unstable), thrombolysis
Complications-device migration, filter embolization, filter
fracture, perforation of IVC, recurrent DVT, vena cava
thrombosis

53. Intraarterial thrombolysis
 In IA thrombolysis, the cervicocephalic arterial tree is
traversed with an endovascular microcatheter delivery
system, the catheter port is positioned immediately within
and adjacent to the offending thrombus, and fibrinolytic
agents are infused directly into the clot. This delivery
technique permits high concentrations of lytic agent to be
applied to the clot while minimizing systemic exposure.
 In acute ischaemic stroke within 6 hours of symptom onset
 It is usually infused over 1 to 2 hours while serial
angiographic studies are obtained
 reduced hemorrhagic complications (due to the use of
lower doses of pharmacologic thrombolytics

54.  Myocardial infarction, ischaemic stroke, massive PE,
acute limb ischaemia
 Recanalization rates for IAT have been shown to be
superior to those for IVT for major cerebrovascular
occlusions, averaging 70% versus 34%
 Agents used
 Streptokinase
 Urokinase
 Recombinant tpa
 Alteplase
 Reteplase

55. Contraindications to thrombolysis
 Intolerable ischaemia(for arterial thrombosis)
 Active bleeding(not including menses)
 Recent stroke or neurosurgical procedure < 2 months
 Intracranial neoplasms
 Recent major surgery(<2 weeks), major trauma,parturition,
organ biopsy
 Active peptic ulcer or recent GI bleed(<2 weeks)
 Uncontrolled HTN
 Bacterial endocarditis, left heart thrombus, hemorrhagic
diabetic retinopathy
 Coagulopathy or current use of warfarin
 pregnancy

56. Endovascular aneurysm
repair(EVAR)
 Indications-
 Symptomatic aneurysm of any size
 Aneurysm >5.5cm in size(5 cm in females)
 Increase in diameter > 0.5 cm/yr
 Saccular aneurysms
 Poorly controlled HTN(DBP>100mmHg)
 Significant COPD(FEV1 <50% of predicted value)
 Contraindications-recent MI, intractable CHF,
unreconstructible CAD, life expectancy <2 yrs,
incapacitating neurologic disease after a stroke

57.  EVAR-suitable in 50% of infrarenal aneurysms
 Reduced mortality and morbidity, shorter hospital stay
 Similar rates of survival to open surgery
 Close follow up with CT necessary
 Unsuitable- short, flared or angulated neck, presence
of intraluminal thrombus and significant calcification,
renal artery/large accessory renal artery arising from
proximal neck, horseshoe kidney, iliac artery
tortuosity, calcification and luminal narrowing

59.  Complications
 Early-branch occlusion, distal embolization, graft
thrombosis and arterial injury
 Arterial dissection
 Bowel ischaemia, renal dysfunction
 Graft migration(1-6%)
 Endoleak- is defined as failure to exclude the
aneurysmal sac fully from arterial blood flow, potentially
predisposing to rupture of the aneurysm sac

61. Endovenous ablation of various
veins
 Endovenous laser ablation(EVLA)- 2001
 Radiofrequency ablation(RFA)
 Indicated in primary and recurrent varicose
veins(recurrent surgery-40% complication rate)
 Procedure includes the insertion of a probe into the greater
saphenous vein under usg guidance. Emits either laser or
radiofrequency energy, which coagulates the vein walls,
causing lumen obliteration.
 RFA-85-120 celsius
 Effectively treats junctional and truncal incompetence.
Varicosities are better treated with concomitant
phlebectomy

62.  Complications- pain. RFA>EVLA
 Skin burns
 DVT and pulmonary embolism(1%)
 Vein perforation and hematoma
 Paresthesia
 phlebitis(<5%)
 recurrence

63.  Tumescent anaesthesia-dilute
lidocaine+adrenaline+bicarbonate
 Max dose (xylocaine+ adrenaline)in tumescent
anaesthesia-45-50mg/kg body weight
 Provides analgesia, increasing contact with vein wall
and laser/RF, protect adjacent structures- skin, nerves

64. Embolisation
 Therapeutic embolization is a nonsurgical, minimally invasive
procedure performed by interventional radiologists and
interventional neuroradiologists . It involves the selective
occlusion of blood vessels by purposely introducing emboli.
 Recurrent hemoptysis
 Arteriovenous malformations(AVMs)
 Cerebral aneurysm
 Gastrointestinal bleeding
 Epistaxis
 Varicocele
 Primary post-partum hemorrhage
 Surgical hemorrhage
 Uterine fibroids

65.  Kidney lesions
 Liver lesions, typically hepatocellular carcinoma
(HCC). Treated either by particle infarction or
transcatheter arterial chemoembolization (TACE).
 Uterine fibroids
 Access to the organ by guidewire and catheter
 Location of the pathology by DSA

66. Embolic agents
 Liquid embolic agents
-used in AVMs. Flows through complex vascular
structures, so need not target each vessel
 N-butyl-2 cyanoacrylate
 Ethiodole
 onyx
 Sclerosing agents
-slow setting, cannot be used for large/high flow vessels
 Ethanol
 Ethanolamine oleate
 sotradecol

67.  Particulate embolic agents
 Gelfoam
-temporary occludes vessels
-used for hemostasis
 Poly vinyl alcohol(PVA)-
-microspheres of 50-1000 micron
-cause inflammatory reaction causing vessel occlusion
 Acrylic gelatin microspheres

68.  Mechanical occlusive device
 Coils
-used for AVM, aneurysm and trauma
-good for fast flowing vessels- immediately clot the
vessel. Platinum or steel
-induce clot due to dacron wool tails around the
wire
 Detachable baloon
- balloon implanted into a vessel, fill with saline

71. Advantages
 Minimally invasive
 No scarring
 Minimal risk of infection
 No or rare use of general anesthetic
 Faster recovery time
 High success rate compared to other procedures
 Preserves fertility and anatomical integrity

72. Disadvantages
 User dependent success rate
 Risk of emboli reaching healthy tissue potentially
causing gastric, stomach or duodenal ulcers. There are
methods, techniques and devices that decrease the
occurrence of this type of adverse side effect.
 Not suitable for everyone
 Recurrence more likely

73. Transcatheter arterial
chemoemolization
 Transcatheter arterial chemoembolization (also called
transarterial chemoembolization or TACE) is a minimally
invasive procedure performed in interventional radiology to
restrict a tumor's blood supply. Small embolic particles coated
with chemotherapeutic agents are injected selectively into an
artery directly supplying a tumor.
 two primary mechanisms.
- arterial embolization preferentially interrupts the tumor's blood
supply and stalls growth until neovascularization.
- focused administration of chemotherapy allows for delivery of a
higher dose to the tissue while simultaneously reducing systemic
exposure, which is typically the dose limiting factor. Effectively,
this results in a higher concentration of drug to be in contact
with the tumor for a longer period of time.

74.  Embolization induces ischemic necrosis of tumor
causing a failure of the transmembrane pump,
resulting in a greater absorption of agents by the
tumor cells. Tissue concentration of agents within the
tumor is greater than 40 times that of the surrounding
normal liver.
 Clinical applications- hepatocellular carcinoma,
neuroendocrine tumours, ocular melanoma,
cholangiocarcinoma, sarcoma, metastatic colon cancer

76.  Lipiodol- mixed with chemotherapeutic agents
 Drug eluting particles
-PVA microspheres-loaded with doxorubicin
COMPLICATIONS
-necrosis of tumours release cytokines causing pain,
fever and malaise
-intrahepatic abscess, irreversible hepatic necrosis
- Restrict TACE to single lobe or major branch of hepatic
artery

77. Thank you