Interventional Radiology

Part I:

balloon angioplasty & stenting

Seldinger technique

percutaneous, endovascular access

for diagnostic & therapeutic

minimally invasive proceduresSven-Ivar Seldinger 1921-1998

puncture needle guide wire needle remove catheter

This technique is used to acess every fluid collection !!!

biliary ducts, kidney collecting system, cysts, absceses, etc.

A little bit of history of endovascular medicine

Werner Forssmann1904-1979

Charles Dotter1920-1985

Andreas Gruentzig1939-1985

1929 – the first documented catheterization of human heart

1964 – the first percutaneoustransluminal angioplasty (PTA)

1974 – the first percutaneousperipheral balloon angioplasty

Artery puncture site percutaneous endovascular access

Peripheral balloon angioplasty & stentingwhat is the idea ?

Peripheral vascular interventions

balloon angioplasty (PTA) & stenting

Peripheral balloon angioplasty

Percutaneous Transluminal Angioplasty (PTA)

PTA alone – success rate depends on anatomic location

subclavian arteries → up to 70%; Iliacs → 40-50%; SFAs → 20-30%

Peripheral stenting

where & when ? → not successful or complicated PTA

PTA is not successful

- elastic recoil (residual stenosis)

- early restenosis

Dissection of dilatated artery

- relatively seldom in peripheral arteries

Atherosclerotic plaques dissection

- very frequent in peripheral arteries

Metallic vascular stents

two basic types of stents

balloon expandable self-expandable

Nowadays – lots of different stents on the market includingdrug-eluting stents to retard the development of neointimal hyperplasia

Vascular stents ballon- & self-epandable

Endovascular stentingcomplications after balloon angioplasty

PTA→

Endovascular stentingalmost always used when arterial occlusions are treated

Thrombo-aspirationlarge lumen caheteror introducer sheath

Transcatheter direct thrombolysis

local administration of thrombolytic agent

urokinase500000–1000000 IU

rtPA 20-40 mg

or

Trombolysis & stenting popliteal occlusion

occlusion → thrombolysis → PTA → stenting

Mechanical aterectomy / thrombectomy similar idea - many different devices

But before we start !!! the patient must be prepared for endovascular treatment ?

4 to 6 hours after last meal (because of contrast medium)

the patient must be hydrated (because of contrast medium)

100 mg of ASA – 4 days before procedure

with controlled blood tests & coagulation factors

all patient’s medicines must be taken

3000 – 5000 IU of heparin - administered during procedure

100 mg of ASA + 2 x 75 mg of clopidogrel - after procedure

Procedure plan is importantmost of patients are already pre-diagnosed

proper choice of vascular access

good quality of diagnostic angiography

proper choice of endovascular equipment:

introducer sheath, giude wires, ballon catheters, stents

direct retrograde femoral approach

cross-over antegradefemoral approach

antegrade axillary approach

Peripheral ballon angioplasty & stentingdifferent procedure in different anatomic locations !!!

Lower limb arteries:

- aorto-iliac intervention

- SFA & popliteal procedures

- below-the-knee arteries (diabetic foot patients)

Aortic arch branches:

- subclavian, innominate & common carotid arteries

- extracranial internal carotids

- vertebral arteries

Abdominal aortic branches:

- renal arteries

- celiac trunk & mesenteric arteries

Upper limb arteries:

- subclavian, axillary & brachial arteries

PTA of aortic stenosis

isolated stenosis of abdominal aorta is a very seldom casebut very spectacular endovascular outcome

High-grade excentric stenosis of AA

implantation of balloon expandable stent

Stenosis in aortic bifurcation

„kissing balloon / kissing stent” technique

Iliac PTA & stenting

the most frequent &

the most successful endovascular procedure

Iliac stenosis

the best long-term results

Iliac stenoses / oclusionsvery spectacular → to avoid abdominal surgery

Iliac oclusions

success rate fifty / fifty

PTA alone of SFA stenosis ?

sufficient results in only about 30% of cases

To revascularize arterial stenosis is easybut when artery is occluded ?

SFA occlusions stenting is usual !!!

Subintimal angioplastyanother solution for long SFA occlusions

SFA stenosis in young patient any alternative procedures ?

what else if not stents ? balloon cryoplasty

Popliteal artery recanalisation

recanalisation

balloon dilatation

stenting

Below-the knee PTA & stenting

surgery and pharmacology - not much to offer in CLI patients

relatively seldom in atherosclerotic patients!!!

after 1 year

Popliteal & BTK interventionsfrequent in diabetic patients

diabetic macroangiopathy affects small BTK arteries !!!

Patient with diabetic foot PTA with special, low-profile balloons

posterior tibial artery recanalization

Patient with diabetic foot

to heal the ulceration !!!

Aortic arch arteries PTA / stentingsubclavian steal syndrome

Left subclavian artery 80%

Brachio-cephalic trunk 10%

Right subclavian artery 5%

Left common carotid artery 3%

Axillary / brachial artery 2%

Supra-aortic PTAendovascular treatment is a method of choice

Aortic arch arteries occlusions

stenting is mandatory

success rate is about 50-60%

Right subclavian artery stenosis

right subclavian steal syndrome – no difference with the left side

Brachio-cephalic trunk obstructions make different clinical situation

Left CCA stenosis

very seldom but important !!!

subclavian / axillary / brachial

seldom but relevant → poor collateral circulation

Carotid stenting (CAS) differs from other PTA / stenting procedures

it needs embolic protection to prevent stroke !!!

The idea of CAS is

to prevent stroke by improving cerebral circulation

normalisation of ”circle of Willis”

Vertebral artery PTA / stentingoccasional & dangerous

only when contralateral VA is not properly patent

(hypoplastic, thrombosed – occluded or highly stenosed)

Renal artery PTA & stenting

patients with renal insufficiency (in progress)

• bilateral renal artery stenosis• artery stenosis to solitary kidney

Renal artery PTA & stenting

to treat reno-vascular hypertension

• still discussed indication• better BP control - 30-40% of patients

Indications for PTRA

The indications of renal angioplasty are still

evolving. The common indications are as follows:

•Sudden onset of HTN

•HTN in a patient without a positive family

history

•HTN in a patient without a medical history of

factors known to cause HTN

•Malignant HTN

•HTN refractory to pharmacotherapy

•Patient noncompliance with medications

•HTN in a patient with abdominal bruit suggestive

of renal artery narrowing

•HTN in a patient who develops renal failure

while taking captopril

•Sudden-onset HTN in a young woman not taking

oral contraceptives (for patients in this group, the

likelihood of fibromuscular dysplasia [FMD] is

increased)

Renal artery stenosis

Indications for PTRA or renal stenting

Indications for PTRA or renal stenting include the following:

•Progressive decline in renal function

•Accelerated or difficult-to-control HTN - Presence of greater than 75% RAS (if

bilateral – stenting!!!) and one of the following: (1) HTN requiring three or more

medications for control, (2) HTN on treatment with mean BP greater than 110

mm Hg, (3) chronic renal insufficiency with creatinine less than 3 mg/dL, or (4)

acute renal failure with preserved renal size and echogenicity on

ultrasonography

Other expanding indications include the following:

Congestive heart failure (CHF)

Unstable angina

Recent development of ESRD that is partly the result of RAS (the patient may be

able to avoid dialysis)

Angiographic lesion in the absence of HTN or renal insufficiency [21]

Patients with unstable angina or CHF and refractory HTN and up to 70%

stenosis of one or both renal arteries (in one study, renal stenting resulted in

dramatic improvement independent of coronary angioplasty [22] )

High-grade RAS in patients undergoing infrarenal abdominal aortic aneurysm

repair [23]

young patients, mostly women - good indication for PTA

Renal artery stenosis fibro-muscular dysplasia / vasculitis

8 years later

Coeliac trunk stenosis / occlusion in most patients asymptomatic !!!

SMA PTA / stenting to treat abdominal angina ?

abdominal angina → bowel ischemia

• AMS stenosis or short occlusion IS usually asymptomatic

• AMS thrombosis or main trunk occlussion may cause symptoms

SMA recanalisation in symptomatic patient

Multi-level, complex procedures

subclavian and iliacstenosis

at the same time?

Restenosis & long-term outcomerestenosis can be treated by endovascular means !!!

restenosis after PTA → stent implantation → in-stent restenosis

elastic recoilor new stenosis

neo-intimalhyperplasia

• drug-eluting stents• carbon coated stents• covered stents

In-stent restenosis genetic predisposition? (6-12 months)

normal re-PTA or cutting balloon

Smaller artery – restenosis more possible

the most frequent in-stent restenosis in SFA

Stent fracture possible in flexion area → SFA

Iliac stent restenosis

especially when close to aortic bifurcation

Renal stent restenosis

in a patient with FMD

Subclavian stent restenosis

repeated restenosis

covered stent (stentgraft) implantation

Vascular surgery complications

restenosis in by-pass graft anastomoses

Vascular surgery complications

iliac dissection after surgical stripping

Dialysis shunt interventionsstenosis occurs in a-v anastomosis & efferent vein puncture sites

PTA is effective and helps avoid another surgery

Dialysis shunt interventions

high-pressure balloons (up to 25 atm) & cutting ballons are used

stenting is occasional

Venous interventions

Central venous obstructions

• neoplasmatic infiltration (bronchial ca, RCC etc.)

• external compression (tumours, lymphadenopathy)

• foreign bodies (central venous access, pacemaker electrodes)

• spontaneous thrombosis ?

• trauma, iatrogenic injuries (seldom)

Peripheral DVT is treated conservatively

but there are some endovascular experiments !!!

Central venous PTA and stenting

pacemaker electrodes

SVC syndrome

Central venous PTA & stenting

VCS syndrome (bronchial ca)

PTA & stentingof „peripheral” veins

post traumatic axillary vein occlusion / thrombosis

venous PTA & stentingchronic occlusion of left brachio-cephalic vein

stent

PTA

IVC occlusion + lower limb DVTendovascular progress to treat peripheral thrombosis ?

• local thrombolysis• PTA / stents

We are still afraid of pulmonary embolism !!!