• No conflict of interest

DECLARATION OF CONFLICT OF INTEREST

Whole body MR-

angiography

Deniz Bilecen, MD, PhD

Kantonsspital Bruderholz, Schweiz ESC 2011

- Motivation: Why Whole body MR angiography ?

- Technical setup: MR scanner and contrast agent

- WB MR-angiography: Some examples

- Take Home Message

- Technical drawbacks

Overview:

Why is a comprehensive assessment of the underlying vascular

pathology required to manage atherosclerotic disease adequately ?

Patients with CAD and PAOD have greater morbidity and mortality

among patients. Patients with CAD and PAOD had a greater risk of cerebral

vascular accidents after myocardial revasculariiation and a 25% increase in

mortality. Higgins TL, et al.JAMA 1992;267:2344-2348.

Peripheral arterial occlusive disease (PAD) in patients with coronary

artery Disease (cAD) compromises the recovery and postoperative (post-

interventional ?) quality of life of patients who undergo myocardial

revascularization). Nikolsky E, et al. Am. J. Cardiol 2004; 93:1536-1539.

Early identification of PAOD by vascular surgens in patients with CAD

is fundamental to reduce morbidity and mortality Eagle KA, et al. J. Am Coll Cardiol 1994

4.7%

44,6 %

16.6%

4.7%

1.2% 1.6%

REACH servey „Reduction of Atherothrombosis for Continued Health“

Coronary

artery

Disease (CAD)

PAD

Carotid

artery

Disease

PAD, CAD and carotid artery disease:

8.4%

4.7%

44,6 %

16.6%

4.7%

1.2% 1.6%

Coronary

artery

Disease (CAD)

PAD

Carotid

artery

Disease

8.4%

The links between PAD and

cerebral artery diseases

seems to be weaker

What does it tell us ?

~10 % of patients with CAD

have PAD

60% (!) of patients with PAD

have CAD or carotid artery

disease

REACH servey „Reduction of Atherothrombosis for Continued Health“

Imaging modalities für delineation of atherosclerosis for screening

purpose:

-Digital subraction angiography

GOLD standard, catheter technique invasive, high radation exposure.

-Duplex-doppler Sonography

lack of radiation, BUT not all vessel terretories are visible, time consuming,

operator-dependent.

-Whole Body CT angiography

Radiation exposure, BUT not all vessel terretories are visible, nephrotoxic CA.

-Whole Body MR angiography

lack of radiation, overall view - BUT not all vessel terretories are visible, +/-

nephrotoxic CA (NSF)

Whole body MR has been proposed ten years ago by Ruehm et al.

entiteled:

Rapid magnetic resonance angiograpy for detection of athererosclerosis

Lancet 2001 Apr 7;357(9262):1086-91

Whole body MRA enables the delination of the arterial vessel

system from Head to Toe using a multi-step imaging technique

+ iv.contrast agent…

Technical setup: The MR scanner

For Whole Body MR angiography standard scanner are suitable and

available at 1.5 T or 3 T

To gain good image qualitiy MR-angiography should be performed using

dedicated surface coils.

Technical setup: The MR scanner

Examples of linear (gadodiamide) and macro-cyclic

(gadobutrol) gd-CA.

Technical setup: The contrast agent:

Contrast agent: CAVE nephrogenic systemic sclerosis (NSF):

NSF is a serious disabling disorder with preciable mortality. rare and serious

syndrome that involves fibrosis of skin, joints, eyes, and internal organs. Its

cause is not fully understood.

However, there is much evidence to suggest that it is associated with

exposure to gadolinium

By far the largest number of cases to date have been associates with severe,

often terminal renal function impairment requiring dialysis.

High risk group in patients with renal insufficiency: patients with eGFR values

< 30 mL/min/173m2

The moving (or rolling) table approach:

Scan 1

STEP I

Scan of supraaortal vessels

10-20 s / step

First iv CM injection

The moving table approach:

Scan 2

STEP II

10-20 s / step

Scan of crural vessels

The moving table approach:

Scan 3

STEP III

10-20 s / step

Scan of thoracic/abdominal aorta

Second iv CM injection

The moving table approach:

Scan 4

STEP IV

10-20 s / step

Scan of abdominal aortal/iliac artery

The moving table approach:

Scan 5

STEP V

10-20 s / step

Scan of femoral/popliteal artery

Whole body MRA ist something like riding a „rollercoaster“

1° injection

2° injection

Thre result of Contrast-enhanced WB MRA of a healthy volunteer

what you get:

Common

carotid artery Abdominal

aorta

Renal artery

Deep femoral

artery

popliteal

artery

Vertebral

artery

Subclavian

artery

Thoracic

aorta

CIA

EIA

Femoral

artery

ATA PA

PTA

IIA

WB-MRA: What about Senistivity and Specificity ?

Herborn et al.: AJR; 182:1427-1434

Goyen et al.: Radiology; 224:270-277

Carotid artery

Thoracic and Abdominal Aorta

Renal arteries

Iliac arteries

Femoral arteries (deep and

superficial)

Crural arteries.

Not (yet)

Coronary arteries

Intracranial arteries

Good imaging quality in WB MR-Angiography is

available for the major vessel territorries of:

Whole Body MRA should provides information about the

A ) Overall burden of atherosclerosis (scoring scheme ? risk management)

B) Delineates arterial stenosis and occlusion of arteries

(+ aneurysms, + variants, roadmap for interventional planning ?)

C) Might provide additional information („overview) of the human body including

organs (kidney, liver), skelettal system etc)

distal narrowing

of abdominal aorta

significant stenosis

of innominate artery

Example I

Example II

significant stenosis

of the common iliac

artery

significant stenosis

of the femoral artery

Occlusion of the femoral artery

occlusion of the

femoral artery

occlusion of

the posterior

tibial artery

occlusion common

iliac artery

Problem: Venous contamination

Mismatch in CM bolus timing,

Combination of veins and arteries

Drawbacks: Stent artifacts

Signal loss due to shielding arti- fact of the stent

Drawbacks: Metal artifacts

a) Technical equipment (including dedicated suface coils !)

b) Eperienced technicians for precised bolus timing and MR scanning

c) Artifacts due to metal implants

d) Contraindications for MR scanning (e.g. Pacemaker/ICD)

e) Renal insufficiency (cave: nephrogenic systemic sclerosis (NSF))

Why is Whole Body MRA not yet a part of for

clinical routine ?

Whole body MRA enables the evaluation of arterial

stenosis, occlusions, and aneurysms with high

sensitivity/specificity

(= atherosclerotic load scoring of atherosclerosis).

Whole body MRA delineates the arterial system from head to toe

(excluding the intracranial and coronary arteries) in one single

examination.

Whole body MRA provides a „roadmap“ for precise planning of

an interventional procedure.

Take home message:

Thank you for your attention !