Progress of MRI-guided EP Interventions is Hampered by a Lack of

ECG-based Patient Monitoring – An Engineering Perspective

Johannes Krug Passand

1,2

and Georg Rose

1,2

Department of Medical Engineering, Otto-von-Guericke University Magdeburg, Germany

Forschungscampus Stimulate, Otto-von-Guericke University Magdeburg, Germany

Keywords:

Cardiology, CMR, ECG, EP, Minimally Invasive Intervention, MRI.

Abstract:

This position paper discusses the current developments and advances of electrophysiological (EP) interven-

tions guided by magnetic resonance imaging (MRI) and the associated technological challenges and difﬁcul-

ties which need to be overcome in the future. MRI provides several advantages compared to other medical

imaging modalities. However, performing any kind of intervention or surgery in an MRI scanner is technical

challenging. EP procedures are a special case since they involve many sensitive electronic stimulation and

measurement devices and also require a high quality patient monitoring. Monitoring the patient’s electrocar-

diogram (ECG) inside an MRI is a challenging task due to the MRI’s hazardous environment. Hence, ECG

signals are highly distorted and are of limited diagnostic value. This limitation in ECG-based patient moni-

toring and the lack of a fully functional, MRI-conditional 12-lead ECG hampers or delays the progress of EP

procedures during MRI. We review and discuss the main reasons for this limitation and give an outlook and

recommendation for further research approaches.

1 INTRODUCTION

Magnetic resonance imaging (MRI) is a medical

imaging modality which is used for a wide range of

diagnostics purposes such as the identiﬁcation of can-

cer tumors, for cardiovascular diseases or the function

of the brain. Cardiac MRI (CMR) is one very impor-

tant application of MRI used to study the anatomical

and functional properties of the heart muscle and the

related blood vessels. In addition to its diagnostic us-

age, MRI has a high potential for guiding minimally

interventions, where it is referred to as interventional

MRI (iMRI) (Barkhausen et al., 2017). One type of

these interventions are electrophysiological (EP) pro-

cedures which are used to diagnose and treat malfunc-

tions of the cardiac’s electrical generation and con-

duction system. EP procedures are minimally inva-

sive interventions, which are until now guided by X-

ray or ﬂouroscopy. Specialized electrode catheters are

used to measure the electrical potentials at the inner

surface of the heart. Depending on the type of diagno-

sis, treatment can be performed subsequently, e. g. by

ablation catheters. EP procedures could beneﬁt from

the advantages provided by MRI (Lederman, 2005).

For performing an EP procedure under MRI-

guidance, patient monitoring is a crucial aspect.

One of the most important physiological signals

in an EP procedure is the patient’s electrocardio-

gram (ECG) (Haines et al., 2014). However, acquir-

ing, processing and analysing an ECG during MRI is

a challenging task whereas the diagnostic value of the

processed ECG is nowadays very limited (Oster and

Clifford, 2017).

We represent the position that the lack of reliable,

ECG-based patient monitoring is one of the reasons

why the progress of MRI-guided EP interventions is

hampered and slowed down. In order to discuss our

position and perspective, this paper gives an overview

of trends in MRI-guided EP interventions, reviews the

currently existing challenges and gives a broad out-

look on future developments in terms of hardware and

software.

2 BACKGROUND

2.1 Patient Monitoring in MRI

Patient monitoring during MRI exams or interven-

tions is a crucial task which is hampered by the

hazardous MRI environment. Several vital signs

Passand, J. and Rose, G.

Progress of MRI-guided EP Interventions is Hampered by a Lack of ECG-based Patient Monitoring – An Engineering Perspective.

DOI: 10.5220/0007485702010208

In Proceedings of the 12th International Joint Conference on Biomedical Engineering Systems and Technologies (BIOSTEC 2019), pages 201-208

ISBN: 978-989-758-353-7

201

of a patient can be monitored such as invasive and

non-invasive blood pressure, respiration, gas analysis,

oximetry, body temperature, or the ECG. There a sev-

eral conditions under which the vital signs of a pa-

tient should be monitored, among them: sedated pa-

tients, critical care patients, patients which are unable

to communicate, or patients undergoing an interven-

tional MRI.

During the last two decades, the demand for high-

quality patient monitoring systems raised due to the

potential and new applications of MRI and MRI-

guided interventions. This includes interventions

such as catherizations or biopsies (Razavi et al., 2003;

Ratnayaka and Lederman, 2010; Fischbach et al.,

2013) and MRI-guided EP interventions (Dukkipati

et al., 2008; Schmidt et al., 2009; Koopmann and

Marrouche, 2013; Piorkowski et al., 2013; Chubb

et al., 2017; Elbes et al., 2017; Mukherjee et al., 2018;

Sommer and Mont, 2018).

The following sections brieﬂy review MRI-guided

EP procedures, give an overview of available or nec-

essary equipment to perform interventions in this en-

vironment and elucidate the need for a reliable, diag-

nostic ECG during MRI.

2.2 MRI-guided EP Procedures

Opposed to X-ray imaging or ﬂuoroscopy, MRI pro-

vides a superior soft tissue contrast, allows a 2D,

3D or 4D visualisation of the heart and other organs

and is used as a standard diagnostic tool for a wide

range of medical applications. Considering interven-

tional EP procedures, MRI provides additional diag-

nostic information. It enables the detection of scar

tissue which can be found in patients with ventricular

tachycardia (Stevenson, 2009), or of febrosis seen in

patients with atrial ﬁbrillation (Mewton et al., 2011;

Dzeshka et al., 2015). MRI also has the potential

to visualise lesions induced by radiofrequency abla-

tion (Vergara et al., 2011; Hunter et al., 2013).

The beneﬁts of an MRI-guided EP can be summa-

rized as follows: 1) improved substrate identiﬁcation

resulting in a more precise ablation targeting, 2) im-

proved guidance during the intervention and 3) an im-

proved assessment of the lesion formation after an ab-

lation (Chubb et al., 2017).

CMR enables the identiﬁcation and differentia-

tion of atrial and ventricular arrhythmogenic sub-

strates (Ashikaga et al., 2007). This information is

increasingly used for guiding cardiac interventions. It

would be even more helpful and expedient when it is

directly available during the EP procedure.

Procedure guidance can be improved by CMR

compared to the conventional, established ap-

proaches. Currently, the more complex EP procedures

are performed by combining X-ray ﬂouroscopy (for

anatomical guidance) and electroanatomic mapping

techniques. The structural information provided by

this approach is inferior to the anatomical and func-

tional information achievable by CMR. CMR pro-

vides more detailed information about the chamber of

interest but also about surrounding structures such as

coronary arteries.

Evaluation of ablation lesions is another potential

advantage of CMR over the other imaging modalities.

CMR could directly be used to assess acute ablation

lesions instead of a post-procedure analysis.

2.3 Selected iMRI Equipment

Performing an MRI-guided intervention in general

and a cardiac intervention in particular requires ded-

icated hard- and software. Starting with the basic re-

quirement, i. e. the MRI scanner, a wide-bore MRI

scanner with 1.5 T or 3 T is the most common choice

nowadays. Open bore MRI scanners systems would

be ideal for any kind of intervention but their produc-

tion was unfortunately discontinued (such as Philips’

Panorama HFO 1 T or GE’s SIGNA SP 0.5 T Open

Conﬁguration). For displaying MR images inside the

scanner cabin, in-room displays are either provided

by the scanner manufacturers or by third party compa-

nies. The scanner vendors also provide software sup-

porting the interventions, such as the Interactive Front

End (Siemens, Germany) or the iSuite (Philips Re-

search Hamburg, Germany). Basic hardware for pa-

tient monitoring is often included in the MRI scanner

system, such as a simple ECG mainly used for trigger-

ing image sequences, a PPG or a respiratory belt sys-

tem. Third party patient monitors include further pa-

rameters such as noninvasive and invasive blood pres-

sure measurements, CO

, temperature and anaesthe-

sia gases. Exemplary MRI speciﬁc patient monitoring

devices are the Tesla M3 (MIPM GmbH, Germany),

the Maglife Serenity (Schiller AG, Switzerland) or the

Expression MR400 (Philips, The Netherlands). Be-

sides patient monitoring, MRI compatible anesthesia

carts are available, e. g. the Aestiva/5 MRI (Datex-

Ohmeda, GE Healtcare, USA). For performing MRI-

guided EP procedures, one MRI-speciﬁc ablation and

monitoring system is currently available including

an ablation catheter and a recording/stimulation sys-

tem (Imricor Medical Systems, USA). In general, the

wide range of tools available for X-ray guided in-

terventions such as different catheters, guidewires,

tracking systems, ablation generators and others are

not available for the MRI environment yet.

For enabling a complete cardiac monitoring, sev-

BIOSIGNALS 2019 - 12th International Conference on Bio-inspired Systems and Signal Processing

202

eral companies and research institutions are working

on 12-lead ECG systems and hemodynamic monitor-

ing platforms since many years or even more than a

decade. But none of these systems is commercially

available or has an FDA clearance or approval. Ex-

amples are the PELEX-MAX (PinMed, USA), the

MiRTLE system (MiRTLE Medical, USA) or ACDx

system (All Clear Diagnostics, USA). There are also

open source research systems such as the Physiolog-

ical Recording in MRI Environment (PRiME) sys-

tem (Kakareka et al., 2018). None of these systems

can currently provide a diagnostic ECG. The reasons

for this circumstance will be explained in the follow-

ing sections.

3 ECG IN MRI - CHALLENGES

The different types of magnetic ﬁelds in an MRI

scanner severely distort the acquired ECG signals.

The signals picked up by the ECG electrodes in an

MRI can be summarized as follows (Felblinger et al.,

1999):

S(t) = S

ECG

+ S

MHD

+ S

IND

(1)

where S

ECG

is the ECG signal, S

MHD

is the signal

caused by the magnetohydrodynamic (MHD) effect,

are gradient distortions and S

IND

are other induced

distortions or noise. Inductions (S

IND

) can occur

when the ECG recorder or the cables are moved due

to respiratory motion. Other sources of induced dis-

tortions are the time-varying, switched gradient mag-

netic ﬁelds and the MRI scanner’s RF ﬁelds. The

RF ﬁelds of clinical scanners have a frequency of

f = 42.58MHz/T · B

where B

is the static mag-

netic ﬁeld strength. This frequency is far beyond

the ECG’s frequency range (approximately 0.05 Hz-

150 Hz). Distortions due to the RF ﬁelds can be

caused by demixing effects in analogue electronic cir-

cuits. The inﬂuence of the RF ﬁelds can be reduced

by a proper shielding of the ECG hardware (Oster

et al., 2010b). This article only considers distortions

induced by the switched gradient magnetic ﬁelds and

the MHD effect.

3.1 Switched Gradient Magnetic Fields

The distortions induced by the switched gradient

magnetic ﬁelds are given as

IND

≈ S



∂G

(t)

∂t

∂G

(t)

∂t

∂G

(t)

∂t



(2)

where G

(t),G

(t) are the gradients used for

image acquisition. The time-varying magnetic ﬁelds

0 2 4 6 8 10

−2

−1.5

−1

−0.5

Time in [s]

Voltage in [mV]

(a) ECG trace with gradient artefacts.

6.105 6.11 6.115 6.12 6.125

−1.5

−1

−0.5

Time in [s]

Voltage in [mV]

(b) Zoomed view of (a) showing a closer view of the artefact

properties.

Figure 1: Gradient artefacts during an MRI sequence (gra-

dient echo).

induce voltages directly within the human torso

but also in the surface spanned by the ECG ca-

bles (Laudon et al., 1998; Felblinger et al., 1999).

Figure 1 shows an exemplary ECG with a gradient

induced distortion during an MRI sequence.

Applying an QRS detection algorithm to such

an ECG signal without further preprocessing would

result in a high number of false positive and false neg-

ative detections due to the high amount of distortions

and the QRS complexes hidden within them. Hence,

suppressing or removing the signal distortions origi-

nating from the time varying switched gradient mag-

netic ﬁelds is usually the ﬁrst signal processing step.

3.2 The Magnetohydrodynamic Effect

The MHD effect results from the interaction between

the pulsatile blood ﬂow, which is caused by the rhyth-

mic action of the heart and the static magnetic ﬁeld

of the MRI scanner, B

. Blood plasma, which makes

up about 60 % of the total blood volume, contains ap-

proximately 10 % solutes including electrolytes such

as Na

, Cl

−

or HCO

−

ions and non-electrolytes (glu-

cose, urea). The ions (electrolytes) are moving inside

the vessels where they experience a force due to the

presence of the MRI scanner’s static magnetic ﬁeld.

This force is known as Lorentz force,

F, where the

force per charge is given as

= (~v ×

B). (3)

Progress of MRI-guided EP Interventions is Hampered by a Lack of ECG-based Patient Monitoring – An Engineering Perspective

203

v(r)

Blood vessel

(a) Outside the MRI

v(r)

Blood vessel

(b) Inside the MRI

Figure 2: A simpliﬁed schematic of the MHD effect inside

a blood vessel. Positive and negative ions are moving with

the velocity v(r) along the blood vessel where r is the ves-

sel’s radius. Outside the MRI scanner, ions are randomly

distributed inside the vessel (a). Inside the MRI scanner

(under the inﬂuence of the static magnetic ﬁeld), the ions

experience the Lorentz force (b).

It depends on the magnitude and orientation of the

blood ﬂow velocity ~v of the charged particles q with

respect to the

ﬁeld. This force causes the ions

to move perpendicularly to the direction of the blood

ﬂow and perpendicularly to the MRI scanner’s static

magnetic ﬁeld. The ions accumulate near the vessel’s

wall leading to a potential difference across the vessel

that can be expressed as

V ∝

~v ×

l (4)

where l is the diameter of the vessel. The voltage es-

timated using Eq. 4 is called Hall voltage. Figure 2

schematically shows how the static magnetic ﬁeld B

affects the moving ions inside the cross section of

a blood vessel. The resulting body surface potentials

of the MHD effect superimpose the ECG signal. Fig-

ure 3 summarizes several physiological and technical

parameters which inﬂuence the MHD effect.

When the ECG is measured inside an MRI scan-

ner, the MHD effect mainly affects the segment be-

tween two QRS complexes, i. e. the ST-segment, the

T-wave and the P-wave. Exemplary ECG signals

from two different subjects acquired outside and in-

side a 3 T MRI scanner are shown in Fig. 4. Since

the MHD effect is directly related to the blood ﬂow,

it mostly affects the ECG during the ventricular sys-

tole where the blood is ejected from the ventricle into

the aorta and pulmonary artery. Hence, the diagnostic

information contained in the ECG’s ST-segment and

T-wave is hidden by the MHD effect which reduces

the diagnostic value of the ECG during an MRI exam

or intervention. For MRI scanners with magnetic ﬁeld

strengths ≥ 7 T, QRS detection can be hampered due

to the large magnitude and slope of the MHD ef-

fect (Krug et al., 2013).

Blood pressure

Blood vessel

diameter

Blood flow

velocity

Stroke volume

Magnetic field

strength

Heart rate

Torso anatomy

MHD effect

Arrhythmia

Intraventricular

flow

Vessel anatomy

......

Figure 3: Selected physiological and technical parameters

affecting the MHD effect.

0 0.1 0.2 0.3

−1.5

−1

−0.5

0.5

1.5

Time in [s]

Voltage in [mV]

(a) Subject A

0 0.1 0.2 0.3

−0.5

0.5

1.5

Time in [s]

Voltage in [mV]

(b) Subject B

Figure 4: Comparison of the ECG signal waveform in

lead II in two different subjects acquired outside (black) and

inside (grey) a 3 T MRI scanner. The QRS complexes are

aligned at t = 0s. The MHD effect mainly affect the ECG’s

ST-segmentand T-wave.

4 CURRENT SITUATION

MRI speciﬁc ECG systems are available from differ-

ent MRI scanner manufactuers and third party ven-

dors. These systems enable the acquisition of ECG

signals under different conditions, i. e. under the pres-

ence of different magnetic ﬁeld strengths and various

imaging sequences. It can be considered that safety

issues, especially due to RF-induced cable heating,

play a negligible role nowadays. The different ven-

dors optimized the ECG electrode positions (close

proximity to the heart), cable resistances (50kΩ to

100kΩ), shielding of the electronics and data trans-

mission in order to obtain a robust signal acquisition

system. A very extensive overview and summary of

these aspects is given in (Oster and Clifford, 2017).

The acquired ECG signals are contaminated by the

effect described in Section 3. Figure 5 brieﬂy sum-

marizes different signal processing steps depending

on the usage of the ECG in MRI.

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ECG

(Clean)

Gradients

MHD Effect

ECG

(Distorted)

Gradient Filter

Diagnostic ECG

QRS Detection

Gating/Triggering

Trigger

Signal

Gradient Filter QRS Detection

Morphological

Information

MHD Filter

Heart rate and

heart rhythm

Figure 5: Signal acquisition and processing chain. For diagnostic purposes, the MHD effect has to be ﬁltered after gradient

ﬁltering in order to enable a morphological analysis of the ECG.

Gradient ﬁltering is usually the ﬁrst processing

step. Several dedicated ﬁltering methods exist to

achieve this goal, e. g. based on independent compo-

nent analysis (Oster, 2009; Oster et al., 2009b), adap-

tive ﬁltering (Kreger and Giordano, 1992; Laudon

et al., 1998; Felblinger et al., 1999; Ab

acherli et al.,

2005; Odille et al., 2007; Wu et al., 2011), Bayesian

ﬁlters (Oster et al., 2010a; Oster et al., 2010b) or me-

dian ﬁltering (Schmidt et al., 2018). The quality of

the different ﬁltering approaches is difﬁcult to com-

pare since it depends on the signal acquisition hard-

ware, the electrode placement and the wire conﬁgura-

tion, sampling rate, analogue ﬁltering stages and oth-

ers. Hence, patient monitoring device manufacturers

employ different methods optimized for their speciﬁc

systems and hardware.

QRS detection: Once the gradients are ﬁltered

from the ECG, the ECG is still superimposed by the

MHD effect. Without further ﬁltering of the MHD

effect, QRS detection is possible in most cases. Ded-

icated QRS-detection algorithms were developed in

the past to cope with the MHD effect enabling a reli-

able QRS detection with a minimized number of false

positives. An early method was based on the vec-

torcardiogram (VCG) (Fischer et al., 1999), which

allowed a spatial separation of the ECG and MHD

signal components. Because of certain limitiations

of the VCG based method at higher magnetic ﬁelds

strengths (≥7 T), a modﬁﬁed VCG based approach

was proposed (Krug, 2015). Wavelets were employed

for QRS detection by means of frequency decompo-

sition (Abi-Abdallah et al., 2006; Sabbah et al., 2007)

or singularity detection (Oster, 2009; Oster et al.,

2009a). Higher order statistics were used to detect

the high slopes of the QRS complex and suppress the

MHD effect (Schmidt et al., 2014).

MHD ﬁltering: To reach the ultimate goal of hav-

ing a fully diagnostic ECG during MRI, MHD ﬁlter-

ing is the most crucial and most challenging aspect in

the whole signal acquisition and processing chain. As

described in Section 3.2, the MHD effect is mainly

caused by the blood ﬂow in the aorta and is highly

correlated with the ECG signal and the cardiac cycle.

The ECG signal – which has its origin in the depo-

larization and repolarization of the cardiac cells – and

the MHD effect can be considered as spatially sepa-

rated sources. The spatial segregation of both sources

makes the problem ideal for source separations tech-

niques such as independent component analysis. Al-

though this method was successfully applied to simu-

lated data (Bhatt and Reddy, 2009), it failed with real

12-lead ECG signals (Krug et al., 2012). The reason

for that is that the different sources highly depend on

each other. The problem of MHD ﬁltering was also

tackled by adaptive ﬁlters (Tse et al., 2014). How-

ever, this method requires a-priori knowledge about

different patient speciﬁc heart beat morphologies used

to train the adaptive ﬁlter. Such data is usually not

available during a real measurement. The most re-

cent research on MHD ﬁltering employs a Baysian

ﬁltering approach in which the ECG and MHD sig-

nal contributions and their (pseudo)-periodic nature

are modelled (Oster et al., 2013; Oster et al., 2015).

The method was applied to simulated and real ECG

datasets contaminated by the MHD effect where it

was shown that it is able to detect simulated patho-

logical alterations of the ECG such as the elongation

of the QT-interval.

5 DISCUSSION AND OUTLOOK

Considering all the potential advantages and bene-

ﬁts of an MRI-guided EP procedure compared to a

ﬂuoroscopy-driven intervention, one may ask why

MRI nowadays is rarely used for these interventions.

Several reasons can be given for the comparatively

slow progress in this ﬁeld: 1) lack of MRI compat-

ible EP hardware, e. g. electrode catheters, ablation

catheters, ablation generators, external deﬁbrillators,

2) patient monitoring hardware and signal processing

algorithms and 3) trained staff to perform interven-

tions in the MRI environment.

The aim of this paper was to emphasize that a di-

agnostic ECG is indispensable for the serious estab-

Progress of MRI-guided EP Interventions is Hampered by a Lack of ECG-based Patient Monitoring – An Engineering Perspective

205

lishment of MRI-guided EP procedures. Tremendous

advances were made in the last two decades includ-

ing the development of acquisition hardware as well

as the software for gradient artefact removal and QRS

detection. Triggering image sequences and monitor-

ing the patient’s heart rate are still the most common

applications of an ECG during MRI. Hence, only few

research was invested in providing a comprehensive

diagnostic (12-lead) ECG within the MRI scanner.

Currently, several prestigious heart centres around

the globe have the ambition to establish or trans-

fer certain EP procedures from X-ray ﬂuoroscopy to

MRI. For this transition, a diagnostic ECG is one of

the key elements. To achieve this goal, the authors

identiﬁed two important issues or aspects which need

to be pursued or addressed by the international re-

search community as well as by the monitoring ven-

dors: 1) the development of an MRI-compatible stan-

dardized 12-lead ECG and 2) the suppression of the

MHD effect.

Several cardiac interventions require a 12-lead

ECG for an optimal disease diagnose or treatment.

Providing a 12-lead ECG in the MRI bore will be

challenging from the hardware development and sig-

nal processing point-of-view due to additional ECG

leads, cables and electrodes, larger electrode dis-

tances (Einthoven triangle) and additional electron-

ics. Current ECG systems used in the MRI scanner

are designed to reduce the inﬂuence of the switched

gradient magnetic ﬁelds and the MHD effect, basi-

cally by a minimization of the electrode distances.

Figure 6 compares the electrode placements of differ-

ent lead systems. Changing from an MRI-optimized

lead system to a conventional 12-lead ECG system

will imply several new problems due to increasing

signal distortions. Hence, new signal processing al-

gorithms or techniques will be required to cope with

these new problems. Having a 12-lead ECG would

facilitate the establishment of MRI-guided EP inter-

ventions. In a ﬁrst step, when the MHD effect is still

present, a 12-lead ECG would enable to perform EP-

procedures mainly requiring information about the

QRS-complex, e. g. the diagnosis and treatment of

ventricular tachycardia. Other interventions requiring

a more detailed morphological analysis of the ECG

such as the P-wave or T-wave could not be performed

at this stage.

The major challenge for the research works within

the next years will be a reliable suppression of the

MHD effect. Much research is necessary for inves-

tigating and developing new signal processing tech-

niques to tackle this problem. Proper experiments and

studies have to be designed in order to collect appro-

priate ECG data from various subjects under different

Lead 2

Lead 1

(a) Reduced lead set

RA LA

LLN

Lead I

Lead III

(b) 12-lead ECG

Figure 6: (a) Typical ECG lead system used during MRI

exams and (b) the conventional 12-lead ECG system com-

prised of the Einthoven triangle and the precordial leads.

conditions. Most experiments conducted in the past

are based on data from healthy subjects, i. e. in the

absence of cardiac arrhythmias or pathologies. This is

the most important limitation of the works performed

in the recent years. One of the most crucial aspects

with the design of the experiments is the fact that the

measurement of an ECG with or without the MHD ef-

fect is not possible under the same condition, i. e. the

ECG during a sudden, unexpected arrhythmic event

will be either measured inside or outside the scan-

ner. However, especially the unforeseen, unknown

arrhythmic episodes where the ECG and MHD sig-

nal components change at the same time are the most

interesting aspect to be studied in the future.

From the authors point of view, the ECG is one

of many elements which play a key-role for the es-

tablishment of MRI-guided EP procedures. It is es-

sential for successful accomplishment of these pro-

cedures and for a positive patient outcome. The de-

velopment and establishment of an MRI-compatible

12-lead ECG will come along with several technolog-

ical challenges but it will enable the establishment of

certain EP procedures using MRI. Once certain pro-

cedures are established and their potential is more

visible to scanner manufacturers and medical device

providers, it can be assumed that this will lead to in-

creasing development efforts in this ﬁeld.

In addition to a reliable diagnostic ECG, other

components such as catheter tracking, ablation and

electrode catheters, ablation generators or external de-

ﬁbrillators need to be developed or adapted in order to

be operated under the very special conditions of the

MRI environment. MRI scanner manufacturers need

to provide appropriate real-time sequences, the inte-

gration of tracking solutions and an adapted workﬂow

to enable a smooth and efﬁcient conduction of the

EP procedures. Only with a combination of different

hardware and software developments and close col-

laboration between scanner manufacturers and third-

party companies, the amazing and promising ﬁeld of

MRI-guided EP procedures can be made accessible.

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206

ACKNOWLEDGEMENTS

The work of this paper was funded by the Euro-

pean Regional Development Fund under the operation

number ‘ZS /2016/04/78123’ as part of the initiative

“Sachsen-Anhalt WISSENSCHAFT Schwerpunkte”.

The authors have no conﬂict of interest.

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