JACC: CLINICAL ELECTROPHYSIOLOGY
VOL. 5, NO. 11, 2019
ª 2019 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
PUBLISHED BY ELSEVIER
High-Resolution Imaging of
LA Anatomy Using a Novel Wide-Band
Dielectric Mapping System
First Clinical Experience
Tilman Maurer, MD,a Shibu Mathew, MD,a Michael Schlüter, PHD,b Christine Lemes, MD,a Johannes Riedl, MD,a
Osamu Inaba, MD,a Naotaka Hashiguchi, MD,a Bruno Reißmann, MD,a Thomas Fink, MD,a Laura Rottner, MD,a
Andreas Rillig, MD,a Andreas Metzner, MD,a Feifan Ouyang, MD,a Karl-Heinz Kuck, MDa
ABSTRACT
OBJECTIVES This study presents the first report of high-resolution imaging of cardiac anatomy using a novel system.
BACKGROUND Recently, the wide-band dielectric mapping system Kodex was introduced.
METHODS This study included 20 consecutive patients with symptomatic atrial fibrillation or left atrial tachycardia who
were scheduled for an ablation procedure and who underwent simultaneous left atrial mapping using the Kodex and
CARTO 3 systems. Pulmonary vein angiograms served as a reference to compare the craniocaudal dimensions of the
pulmonary vein ostia as depicted by either of the 2 mapping systems.
RESULTS Complete left atrial imaging was achieved within a median [first quartile; third quartile] of 9.7 [7.5; 12.8] min.
Median procedure time was 97.5 [90; 112.5] min, and median total fluoroscopy time was 8.2 [5.7; 10.6] min, of which a
median of 1.4 [1.1; 2.3] min were used during the creation of the left atrial map. High-resolution representations of left
atrial anatomy were successfully created in all patients. Both the Kodex and CARTO measurements correlated well with
fluoroscopy measurements, as reflected by Pearson’s correlation coefficients (r) of 0.91 and 0.95, respectively.
Bland-Altman plots revealed that, on average, Kodex measurements underestimated fluoroscopy measurements by
0.04 mm (95% limits of agreement of –5.72 and 5.64 mm), and CARTO measurements underestimated fluoroscopy
measurements by 0.02 mm (95% limits of agreement of –3.61 and 3.57 mm).
CONCLUSIONS Anatomic mapping of the left atrium using Kodex shows the potential to create computed
tomography–like images without the need for additional periprocedural imaging. (J Am Coll Cardiol EP 2019;5:1344–54)
© 2019 by the American College of Cardiology Foundation.
C
atheter ablation of symptomatic atrial fibril-
technically
lation (AF) and left atrial tachycardia (AT)
learning curve (3,4). In this context, precise naviga-
challenging
procedure
with
a
long
has evolved from an experimental proced-
tion of the diagnostic and ablation catheters toward
ure into an established therapeutic option (1,2). How-
the location of interest within the complex anatomy
ever, despite technological advances in ablation
of the human heart is crucial for performing safe
devices, left atrial catheter ablation remains a
and
effective
interventional
electrophysiological
From the aDepartment of Cardiology, Asklepios Klinik St. Georg, Hamburg, Germany; and bAsklepios Proresearch, Hamburg,
Germany. Dr. Maurer has received speaker honoraria and travel grants from EPD Solutions/Philips. Dr. Kuck has received research
grants and is a consultant to EPD Solutions/Philips; and has served as a consultant for Medtronic, Edwards Lifesciences, Boston
Scientific, Biosense Webster, and St. Jude Medical. All other authors have reported that they have no relationships relevant to the
contents of this paper to disclose.
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’
institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information,
visit the JACC: Clinical Electrophysiology author instructions page.
Manuscript received February 22, 2019; revised manuscript received June 24, 2019, accepted June 25, 2019.
ISSN 2405-500X/$36.00
https://doi.org/10.1016/j.jacep.2019.06.020
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procedures. Particularly with the development of
body. The system receives and analyzes the
ABBREVIATIONS
more advanced ablation strategies, such as wide
subtle
AND ACRONYMS
area circumferential pulmonary vein isolation (PVI)
reflection from all catheter electrodes as they
for AF or linear ablation for the treatment of AT, the
are manipulated in the cardiac chambers.
exact localization of anatomic structures and their
Structures such as the endocardial atrial sur-
AF = atrial fibrillation
variations is a prerequisite to understanding the
face, cardiac veins, and heart valves cause
AT = atrial tachycardia
structural substrate that is associated with each spe-
marked gradients in the electrical field. This
CT = computed tomography
cific arrhythmia and to guide its treatment.
“bending of the electrical field” is sensed by
PV = pulmonary vein
the system and used to calculate the geo-
PVI = pulmonary vein isolation
This study presents the first experience with high-
electrical
field
transmission
and
3D = 3-dimensional
resolution imaging of left atrial anatomy using
metric characteristics of the three-dimensional (3D)
the novel wide-band dielectric mapping system
image. With this technique, Kodex can collect
Kodex (EPD Solutions, Philips, Amsterdam, the
anatomic information without immediate physical
Netherlands).
surface contact a few millimeters ahead of the catheter electrodes, resulting in a certain degree of “farfield imaging” (discussed later). The catheter serves
METHODS
as an internal distance ruler for scaling of the geomSTUDY POPULATION. The study population comprised
etry by comparing the known interelectrode spacing
20 consecutive patients with symptomatic, drug-
versus the voltage difference between the 2 elec-
refractory AF or AT who were scheduled for a left
trodes. The system records a specific set of electrical
atrial ablation procedure. Exclusion criteria were a
field descriptors for each specific position of the
left atrial diameter >60 mm, severe valvular heart
catheter within the cardiac anatomy and can thereby
disease, or contraindications to post-interventional
determine relative positions and distances between
oral anticoagulation. All patients provided written
locations within the chamber. At each location, the
informed consent. The study was approved by the
electrical field descriptors that Kodex acquired are
local ethical board and was performed in accordance
used to reconstruct the chamber geometry.
with the Declaration of Helsinki.
Kodex offers 2 distinct options for the operator to
PROCEDURAL MANAGEMENT. Transesophageal echo-
cardiography was performed in all patients to rule out
left atrial thrombus formation before ablation. Direct
oral anticoagulants were paused 1 day before the
procedure and continued 6 h post-ablation. In patients taking vitamin K antagonists, ablation was
performed under therapeutic international normalized ratio values of 2 to 3. All procedures were performed under sedation using intravenous sufentanil,
midazolam, and propofol. A 6-F decapolar steerable
diagnostic catheter (Inquiry, St. Jude Medical, St.
Paul, Minnesota) was positioned in the coronary sinus
from the right femoral vein. Two SL1 sheaths (St. Jude
Medical) were advanced into the left atrium via a
double transseptal puncture guided by fluoroscopy
and using a modified Brockenbrough technique.
Intravenous heparin was administered to maintain an
activated clotting time >300 s during the procedure.
Pericardial effusion after ablation was ruled out in all
patients by using transthoracic echocardiography.
images
of
cardiac
anatomy
image provides a more conventional presentation of
the heart chamber and may be rotated freely. Second,
in an innovative approach, the heart may be opened
virtually across the 3D surface (Figure 1, Online
Video 1). This panoramic view (“PANOV”) offers a
depiction of the endocardial surface within a single
image (Figure 2). The operator may choose the
cutting plane freely to guarantee a clear view of the
region of interest.
High-resolution imaging of the cardiac anatomy
using Kodex is initiated with the introduction of any
catheter into the left atrium (in this study, the mapping catheter). Within seconds, a first instant far-field
image is acquired that depicts the extent of the cardiac chamber and features dimples that indicate the
orifice of structures such as the pulmonary veins
(PVs) or the mitral valve (Figure 3). These landmarks
in the initial image may guide further mapping. More
details are then obtained by navigating the mapping
catheter within the heart chamber and when contact
LEFT ATRIAL IMAGING. The Kodex system creates
high-resolution
visualize the cardiac anatomy. First, a 3D surface
with the target structures is established.
by
For this initial study, the procedure was performed
exploiting the distinct dielectric properties of bio-
according to the institutional standard approach,
logical tissue. For that purpose, multiple anisotropic
performing point-by-point electroanatomic mapping
fields may be induced by 7 external reference patches
using the CARTO 3 system (Biosense Webster, Dia-
on the body surface as well as any electrodes on
mond Bar, California), and data collection for Kodex
diagnostic and/or an ablation catheter in the patient’s
was executed simultaneously. For CARTO 3, at least
É
theorybehind
imaging
dielectric
needknown
electrodedist
paleelectrodes
alayspline
electrodes
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F I G U R E 1 Two Distinct Kodex Options for Visualizing the Cardiac Anatomy
(Left) A conventional 3-dimensional image of the heart chamber shows a detailed depiction of the atrial surface (anterior–posterior and slightly
superior view of left atrium). (Right) Novel panoramic view (“PANOV”) view supplying the operator with a unique endocardial perspective of
the left atrium, revealing anatomic features previously obscure to the clinical electrophysiologist. See Online Video 1. LAA ¼ left atrial
appendage; LIPV ¼ left inferior pulmonary vein: LSPV ¼ left superior pulmonary vein; RIPV ¼ right inferior pulmonary vein; RSPV ¼ right
superior pulmonary vein.
50 uniformly distributed points per map were ac-
imaging was performed. The maximum diameters of
quired. Point collection was gated to an intracardiac
the ipsilateral right-sided and left-sided PV ostia were
atrial electrogram derived from the coronary sinus
measured in the craniocaudal dimension using all 3
diagnostic catheter. Point acquisition was only per-
imaging modalities. Measurements were taken from
formed during expiration. Data collection for Kodex is
the superior edge of the respective upper PV to the
executed continuously through all respiratory pha-
inferior border of the ipsilateral lower PV. Fluoros-
ses, during both inspiration and expiration, and
copy was considered the reference technique, and
during the entire cardiac cycle. The body patch
both
transmission is used to form a signal that correlates
compared against the reference. Linear regression
with the respiratory cycle. These signal data are par-
and Bland-Altman analyses were used to assess the
titioned into different phases of the respiratory cycle.
relation and agreement, respectively, of either imag-
A spatiotemporally smooth transformation is per-
ing/mapping technology (Kodex and CARTO) with
formed from the multiphase point sets to a single-
fluoroscopy.
phase point set that is associated with the end of
inspiration. The cardiac cycle phase is extracted from
electrogram data and is analyzed and partitioned
into phases. Again, a transformation is then built to
project the multirhythm/multiphase point sets into
-
a single-phase point set. The compound-projecting
transformation is used for navigation, aiming at
reducing the effect of both the respiratory and the
cardiac cycles on the position of the catheter while
CARTO
and
Kodex
measurements
were
ENDPOINTS. The primary endpoint of the study was
the completion of left atrial imaging. Secondary
endpoints included: 1) procedural parameters; 2) dimensions of the PV ostia in all 3 imaging modalities;
and 3) procedure-related complications, defined as
transient ischemic attack, stroke, pericardial tamponade or pericardial effusion, bleeding requiring blood
transfusion, and hematoma at the access site.
preserving as much data as possible from the entire
STATISTICAL ANALYSIS. Continuous data are described
mapping process.
as mean ! SD, if normally distributed, or as median
Selective PV angiography was used to visualize the
individual PV ostium (Figure 4). No further cardiac
(first; third quartile). Categorical data are described
with absolute and relative frequencies.
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F I G U R E 2 Gradual Opening of the 3D Model
Gradual virtual opening of a high-resolution anatomical 3D reconstruction of the left atrium generated by wide-band dielectric imaging using
Kodex: (A) 20% opening; (B) 50% opening; (C) 80% opening; and (D) fully opened. All panels show an anterior-posterior view.
shown in Figure 5. Both Kodex and CARTO measure-
RESULTS
ments correlated well with fluoroscopy measurePATIENT
CHARACTERISTICS
AND
PROCEDURAL
ments,
as
reflected
by
Pearson’s
correlation
PARAMETERS. Baseline characteristics of the 20 pa-
coefficients (r) of 0.91 and 0.95, respectively. Bland-
tients are provided in Table 1. Sixteen patients (85%)
Altman plots revealed that, on average, Kodex
presented with symptomatic AF (9 [56%] had parox-
measurements
ysmal AF), and 4 patients (15%) were treated for left
surements by 0.04 mm (indicative of hardly any
AT. Complete left atrial imaging using Kodex was
measurement bias), with 95% limits of agreement of
achieved within a median [first quartile; third quar-
–5.72 and 5.64 mm. Similarly, CARTO measurements
tile] of 9.7 [7.5; 12.8] min. Median procedure time was
underestimated
underestimated
fluoroscopy
fluoroscopy
measurements
mea-
by
97.5 [90; 112.5] min, and median total fluoroscopy
0.02 mm; however, the 95% limits of agreement (–3.61
time was 8.2 [5.7; 10.6] min, of which a median of 1.4
and 3.57 mm) with CARTO were lower by an absolute
[1.1; 2.3] min were used during the creation of the left
value of w2 mm compared with Kodex.
atrial map (Table 2). After left atrial imaging, PVI was
performed in 18 cases. In 3 patients with left AT, a
mitral isthmus line for perimitral re-entrant AT was
performed in 2 patients, and 1 patient was treated for
a focal left AT. Additional creation of a cavotricuspid
isthmus line to ablate typical atrial flutter was done in
3 patients.
VARIATIONS IN PV ANATOMY. The “standard” PV
anatomy consisting of 2 right-sided and 2 left-sided
PVs with separate ostia was depicted in 15 (75%) of
20 patients. In 4 (20%) patients, a common ostium of
the left PVs, defined as the presence of bifurcated PVs
entering the contour of the left atrium together and a
distance between the virtual border of the left atrium
MULTIMODAL PV OSTIAL DIMENSION MEASUREMENTS. The
and the bifurcation of both PVs $5 mm (5,6), was
statistical analyses of PV ostia measurements are
recorded. In 1 patient (5%), imaging revealed an
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F I G U R E 3 Instant Imaging of Cardiac Anatomy
The acquisition process is based on contact and noncontact mapping maneuvers using the ablation catheter. In this PANOV view, the atrium is
opened up completely as it is in Figure 2D. (A to G) After insertion of the catheter, an instant image of the heart chamber is created. Small dents
in the surface point toward the orifice of the septal and lateral pulmonary veins (A). More detail is acquired as the catheter is navigated through
the atrium. Within minutes, a high-resolution image of the atrial geometry is created, including all relevant details such as the pulmonary veins
and their branches, the left atrial appendage, the ridge, and the mitral annulus (H). Abbreviations as in Figure 1.
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F I G U R E 4 Comparison of Left Atrial Anatomy Using Different Imaging Modalities
(A) Point-by-point anatomic map using the CARTO 3 system in a posterior–anterior view (left) and a left lateral view (right). White points in the CARTO map indicate the
ipsilateral pulmonary vein ostium as identified by selective pulmonary vein angiography (B). Angiography in B was performed in a left anterior oblique 40# projection
with white lines highlighting a left common pulmonary vein ostium. (C) Example of the left atrial geometry in the Kodex PANOV view; and (D) the corresponding Kodex
three-dimensional view. CS ¼ coronary sinus catheter; LCPV ¼ left common pulmonary vein; other abbreviations as in Figure 1.
accessory roof PV and a right middle PV with a
ablation has proven to be an effective treatment op-
separate PV ostium. Examples of all variations in PV
tion. The identification of ectopic activity arising
anatomy as imaged by using the Kodex system are
from the PVs as an important trigger in the initiation
given in Figures 4 and 6 and the Central Illustration.
of AF has made electrical isolation of all PVs the pri-
COMPLICATIONS. No complications were observed
in the course of this study.
DISCUSSION
The present study evaluated the feasibility of left
atrial imaging by using a novel wide-band dielectric
mapping system. The findings are as follows: 1) rapid
high-resolution imaging of all details relevant to left
atrial catheter ablation was achieved in all patients
within a median of 9.7 min of mapping time; 2)
measurement of the PV ostia using Kodex imaging
and CARTO 3 mapping revealed a high level of
concordance with angiographic visualization; and 3)
no procedural complications occurred.
mary target of catheter ablation (7,8). The creation of
durable lesions encircling the PVs is paramount for
the long-term success rate of PVI (4), as is the
deployment of permanent lesions for any ablation
strategy (9). However, this goal is not achieved easily,
as the interventional electrophysiologist encounters a
great variation in left atrial anatomy (6,10,11). Among
others, an atypical takeoff of PVs, accessory PVs,
common PV ostia, and particularly the ridge between
the left atrial appendage and the left-sided PVs pose
potential obstacles to the optimal positioning of the
ablation catheter and the successful completion of
PVI or linear lesions.
The population of our study represents a typical
cohort of patients experiencing AF or AT. As expected, a wide disparity in anatomy of the PV ostia
HIGH-RESOLUTION IMAGING OF LEFT ATRIAL ANATOMY.
was noted. Although most patients had 2 ostia on the
AF is the most common arrhythmia, and catheter
right side for upper and lower lobe veins, a common
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Illustration, Kodex imaging displays the transseptal
T A B L E 1 Baseline Patient Characteristics (N ¼ 20)
Age, yrs
Male
Body mass index, kg/m2
LV ejection fraction, %
Hypertension
62.0 ! 11.3
12 (60)
28.4 ! 3.5
57.5 ! 9.1
puncture tract in the anterior wall of the left atrium.
This may guide re-intubation of a previous puncture
site and thereby ease the procedural workflow.
Exact regional anatomic knowledge of the afore-
12 (60)
mentioned structures is essential for an effective and
2 (10)
fast ablation procedure and, importantly, to avoid
Coronary artery disease
1 (5)
complications from damage due to uninformed cath-
Vascular disease
3 (15)
eter manipulation. These important anatomic details
History of stroke/TIA
1 (5)
are underappreciated and often missed by conven-
Diabetes
Congestive heart failure
2 (10)
Left atrial diameter, mm
45.1 ! 5.6
CHA2DS2-VASc score
0
1.95 ! 1.39
3 (15)
tional 3D mapping systems because they only provide
a rough reconstruction of the cardiac anatomy, which
is considerably influenced by the shape of the cath-
1
5 (25)
eter used for mapping. Extrapolation between adja-
2
6 (30)
cent structures such as the left atrial appendage and
3
3 (15)
left PVs in earlier mapping systems results in a
4
2 (10)
considerable loss of crucial detail. Thus far, this
5
1 (5)
shortcoming can only be compensated for by adding
Antiarrhythmic medication at baseline
Beta-blockers
15 (75)
Class I
1 (5)
Class III
4 (20)
additional time-consuming and/or expensive imaging
modalities such as (intracardiac) ultrasound or preprocedural magnetic resonance or computed tomography
Values are mean ! SD or n (%).
CHA2DS2-VASc ¼ congestive heart failure, hypertension, age $75 years,
diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65 to
74 years, sex category; LV ¼ left ventricular; TIA ¼ transient ischemic attack.
(CT)
imaging.
However,
these
imaging
techniques are all influenced by inherent shortcomings such as the lack of real-time imaging or 3D imaging. In this study, imaging with the Kodex system
offered high-resolution images of left atrial geometry
left PV ostium was documented in 20% of patients. In
1 patient, an accessory roof PV with an aberrant
insertion perpendicular to the upper LA posterior wall
was recorded (Figure 6). This rare variation of PV
anatomy was missed by the initial selective angiographic visualization and may have easily been
occluded by ablation if not taken into account when
performing PVI.
Furthermore, a clear understanding of the relative
location of the transseptal sheath to the target sites
within the left atrium is indispensable to a successful
ablation procedure. However, particularly in complex
cases, the ablation catheter may need to be retracted
to the right atrium or be lost inadvertently during the
course of the procedure. As shown in the Central
in CT-like quality without any additional imaging
efforts. Furthermore, most 3D mapping systems
require a person supporting the operator at the table
in adjusting the map. The PANOV view is an important step in making the operator independent from
such assistance as it lays out the complete anatomy in
a single image.
The mapping time (median 9.7 min) and fluoroscopy time (median 1.4 min) required to create images
of left atrial anatomy in this study were at the lower
end of data reported from other trials using other 3D
mapping systems (12,13) or using additional imaging
tools to support mapping with CARTO such as intracardiac
ultrasound or
pre-acquired CT imaging
(14–16). This finding may be attributed to the fact that
the study was performed at a high-volume center and
by experienced operators. Nonetheless, it also shows
the potential of Kodex to create high-resolution im-
T A B L E 2 Procedural Parameters
Total procedure duration, min
97.5 [90; 112.5]
Total fluoroscopy time, min
8.2 [5.7; 10.6]
Dose area product, cGy/cm
517 [360; 758]
Left atrial mapping time, min
9.7 [7.5; 12.8]
ages of left atrial geometry just by using contact and
noncontact mapping maneuvers within a short period
of time.
Earlier studies reported a good spatial correlation
1.4 [1.1; 2.3]
between left atrial volume assessed by biplane angi-
Major
0 (0)
Minor
0 (0)
the findings from the present study showing a high
Fluoroscopy time for left atrial mapping, min
ography and CARTO (17). This scenario is in line with
Complications
Values are median [first quartile; third quartile] or n (%).
concordance with pulmonary angiography and the
ostial diameters of the CARTO maps (Pearson’s correlation coefficient [r] of 0.95). The dimensions of the
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F I G U R E 5 Statistical Evaluation of PV Ostial Diameter Measurements
(A) Correlation of Kodex and fluoroscopy measurements. Solid line represents regression equation; broken lines represent 95% confidence band. Pearson’s correlation
coefficient (r) is 0.91. (B) Bland-Altman plot of Kodex and fluoroscopy measurements. Solid line represents mean difference (Kodex – fluoroscopy) of –0.04 mm between
measurements; broken lines denote upper and lower 95% limits of agreement (!1.96 SDs). (C) Correlation of CARTO and fluoroscopy measurements. Solid line
represents regression equation; broken lines represent 95% confidence band. Pearson’s correlation coefficient (r) is 0.95. (D) Bland-Altman plot of CARTO and
fluoroscopy measurements. Solid line represents mean difference (CARTO – fluoroscopy) of –0.02 mm between measurements; broken lines denote upper and lower
95% limits of agreement. PV ¼ pulmonary vein.
ostial PV diameters measured in the Kodex images
may potentially enable the clinical electrophysiolo-
also correlated well with fluoroscopy measurements,
gist to identify regions with tissue edema that require
as reflected by a Pearson’s correlation coefficient (r)
additional ablation. The implementation of these
of 0.91.
tools is expected to allow for an independent ablation
approach using Kodex without any additional imag-
FUTURE
PERSPECTIVES. This
study presents an
early experience of high-resolution imaging using
ing or simultaneous mapping with a conventional
mapping system.
Kodex. For the near future, the implementation of
Cardiac imaging using Kodex can theoretically be
voltage mapping as well as the annotation of elec-
performed with any catheter that is equipped with
trical cardiac activation is expected. Furthermore, the
electrodes such as a quadripolar ablation catheter
analysis of changing dielectric properties of cardiac
(as used in this study) or any other diagnostic
tissue during/after ablation may be able to distin-
catheter, including, for example, the circular Ach-
guish durable ablation lesions from interposed gaps
ieve Mapping Catheter (Medtronic, Minneapolis,
with only transiently impaired conduction, which
Minnesota) used to guide cryoballoon ablation.
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F I G U R E 6 Typical Examples of High-Resolution Imaging of the Left Atrium With Kodex
(A and B) PANOV views. (C) The corresponding 3-dimensional view. All structures relevant for interventional cardiology in this heart chamber
are depicted in computed tomography–like quality but without the need for additional periprocedural imaging modalities. Of particular interest
for pulmonary vein isolation is the detail of the ridge between the left atrial appendage and left pulmonary veins as well as the high-resolution
visualization of the pulmonary vein branches, the carina between different branches, and the pulmonary vein orifices. C shows a rare variation of
right pulmonary vein anatomy with a separate right middle pulmonary vein (RMPV) as well as an accessory pulmonary roof vein. Abbreviations
as in Figures 1 and 4.
Even though this study did not include patients
Ultimately, tools are under development that will
undergoing
allow cryoballoon visualization capabilities within
cryoballoon-based
PVI,
and
further
research in this area is required, high-resolution
the Kodex system.
Achieve
Theoretically, even a guidewire or a sheath could
Mapping Catheter and may be useful to guide
be visualized by Kodex as soon as they are equipped
cryoballoon procedures as well; it has the potential
with a set of electrodes. This approach may in the
to reduce fluoroscopy exposure for patient and
future allow for fluoro-less guidance of transseptal
operator.
access as well as the ablation procedure. However,
imaging
should
be
possible
with
the
To date, balloon-based approaches for PVI leave
further research in this area is required.
the clinical electrophysiologist largely uninformed
STUDY LIMITATIONS. Because this study presents
about the substrate of the left atrium. Additional 3D
the first experience with using the Kodex system for
(substrate) mapping may be time-consuming and
cardiac imaging, no data on a stand-alone approach
costly. Hypothetically, with the inclusion of voltage
for left atrial mapping are available. The study sam-
and activation data into Kodex, this information may
ple size was small and may be underpowered to
become available just by navigating the Achieve
detect quantitative differences in the navigational
Mapping Catheter during the balloon procedure.
accuracy between the different imaging modalities.
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C EN TR AL I LL USTR AT I O N Endocardial PANOV View of the Left Atrium
Maurer, T. et al. J Am Coll Cardiol EP. 2019;5(11):1344–54.
Endocardial PANOV view of the left atrium showing all anatomical details relevant for catheter ablation including the pulmonary vein ostia, the
left atrial appendage, and the ridge between the appendage and the left superior pulmonary vein. This view is obtained by virtual opening of
the 3D image across the anterior wall. Two distinct puncture sites from double transseptal access (arrow) for pulmonary vein isolation can be
discriminated, with the ablation catheter (blue) exiting the more superior of the 2 access sites. LAA ¼ left atrial appendage; LIPV ¼ left inferior
pulmonary vein; LSPV ¼ left superior pulmonary vein; PANOV ¼ panoramic view; RIPV ¼ right inferior pulmonary vein; RSPV ¼ right superior
pulmonary vein.
Measurements of the ostial PV dimensions in the
PERSPECTIVES
angiograms, CARTO, and Kodex were performed
manually.
COMPETENCY IN MEDICAL KNOWLEDGE: The present
study showed the feasibility of left atrial imaging using the novel
CONCLUSIONS
wide-band dielectric mapping system Kodex with depiction of all
The novel wide-band dielectric Kodex mapping
system shows the potential to create 3D real-time
and high-resolution images of left atrial anatomy
in CT-like quality without the need for additional
imaging.
ADDRESS
Georg,
quality without the need for additional imaging.
TRANSLATIONAL OUTLOOK: Advances in real-time and
high-resolution cardiac imaging are needed to improve the
efficacy and safety of interventional treatment for arrhythmias.
FOR
CORRESPONDENCE:
Dr.
Tilman
Maurer, Department of Cardiology, Asklepios Klinik
St.
details relevant to left atrial catheter ablation in high-resolution
Lohmühlenstr.
5,
20099
Hamburg,
Germany. E-mail: tilmanmaurer@hotmail.com.
According to the first clinical experience reported here,
wide-band dielectric imaging shows the potential to optimize
guiding of catheter ablation procedures in the future.
1353
1354
Maurer et al.
JACC: CLINICAL ELECTROPHYSIOLOGY VOL. 5, NO. 11, 2019
High-Resolution Cardiac Imaging System
NOVEMBER 2019:1344–54
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KEY WORDS arrhythmia, atrial fibrillation,
cardiac imaging, catheter ablation
AP PE NDIX For a supplemental video,
please see the online version of this paper.