Download A survey of German centres performing invasive electrophysiology

CLINICAL RESEARCH
Europace (2013) 15, 1741–1746
doi:10.1093/europace/eut149
Pacing and resynchronization therapy
A survey of German centres performing invasive
electrophysiology: structure, procedures, and
training positions
Hans-Ruprecht Neuberger1*, Roland Richard Tilz 2, Hendrik Bonnemeier 3,
Thomas Deneke 4, Heidi L. Estner 5, Charalampos Kriatselis 6, Malte Kuniss 7,
Armin Luik 8, Philipp Sommer 9, Daniel Steven 10, Christian von Bary11, Frederik Voss 12,
and Lars Eckardt 13
1
Klinik für Innere Medizin III, Kardiologie, Angiologie, Internistische. Intensivmedizin, Universitätsklinikum des Saarlandes, D-66421 Homburg/Saar, Germany; 2II. Medizinische Abteilung,
Fachabteilung Kardiologie, Asklepios Klinik St Georg, D-20099 Hamburg, Germany; 3Schwerpunkt Kardiologie und Angiologie, Klinik für Innere Medizin III, Universitätsklinikum SchleswigHolstein, Campus Kiel, D-24105 Kiel, Germany; 4Klinik für Kardiologie, Herz- und Gefäß-Klinik GmbH, D-97616 Bad Neustadt a. d. Saale, Germany; 5Medizinische Klinik u. Poliklinik,
Interventionelle Elektrophysiologie, Klinikum der Universität München, Campus, Großhadern, D-81377 München, Germany; 6Klinik für Innere Medizin - Kardiologie, Deutsches
Herzzentrum Berlin, D-13353 Berlin, Germany; 7Abteilung Kardiologie, Kerckhoff Klinik GmbH, D-61231 Bad Nauheim, Germany; 8Medizinische Klinik IV, Kardiologie, Angiologie und
Internistische Intensivmedizin, Städt. Klinikum Karlsruhe gGmbH, D-76133 Karlsruhe, Germany; 9Abteilung für Rhythmologie, Herzzentrum der Universität Leipzig, D-04289 Leipzig,
Germany; 10Klinik für Kardiologie mit Schwerpunkt Elektrophysiologie, Universitäres Herzzentrum Hamburg gGmbH, D-20246 Hamburg, Germany; 11Medizinische Klinik I,
Rotkreuzklinikum München, Lehrkrankenhaus der Technischen Universität München, D-80634 München, Germany; 12Innere Medizin III, Krankenhaus der Barmherzigen Brüder Trier,
D-54292 Trier, Germany; and 13Abteilung für Rhythmologie, Department für Kardiologie und Angiologie, Universitätsklinikum Münster, D-48149 Münster, Germany
Received 26 February 2013; accepted after revision 2 May 2013; online publish-ahead-of-print 4 June 2013
Aims
To provide a nationwide survey (and reference for the future) on cardiac electrophysiologists, types and numbers of invasive electrophysiological procedures, and training opportunities in 2010.
.....................................................................................................................................................................................
Methods
German cardiology centres performing invasive electrophysiology were identified from quality reports and contacted to
and results
fill a questionnaire. A majority of 122 centres (65%) responded. Electrophysiology (ablation procedures and device
therapy) was mainly part of a cardiology department (82%), and only in 9% independent (own budget). In only 58% of
the centres, (at least) two physicians were present during catheter ablations. Although in 2010, women represented
59.4% of physicians ,35 years old, only 26% of physicians in electrophysiology training were female. In total, 33 420 catheter ablations were performed with a median number of 180 per centre. Atrial fibrillation (AF) was the most common
arrhythmia invasively treated (35%). At least 50 AF ablations were performed in 53% of the centres. Of the centres performing AF ablations, consecutive left atrial arrhythmias were treated by catheter ablation only in 75%, and only 44% had
in-house surgical backup. Only one-fourth of the 122 centres fulfilled all requirements for training centre accreditation
according to the European Heart Rhythm Association and the German Cardiac Society.
.....................................................................................................................................................................................
Conclusion
The results indicate a high number of electrophysiology centres and procedures in Germany. Atrial fibrillation was the
most common arrhythmia invasively treated. An increasing demand for catheter ablation is likely, but training opportunities are limited. Women are clearly underrepresented. A co-operation of higher and lower volume electrophysiology
centres may be necessary for training purposes.
----------------------------------------------------------------------------------------------------------------------------------------------------------Keywords
Invasive electrophysiology † Catheter ablation † Survey † Training requirements
Introduction
Clinical electrophysiology including device therapy and catheter ablation of arrhythmias is rapidly developing as a subspeciality in cardiology. Today, catheter ablation is the first-line therapy for the
majority of regular supraventricular tachycardias (SVTs) and at
least second-line therapy for most patients with atrial fibrillation
(AF). It has been estimated that about 50 000 catheter ablation procedures are performed every year in Germany.1 Emerging indications, an increasing number of procedures, and the expected
* Corresponding author. Tel: +49 6841 162 3387; fax: +49 6841 162 3381, Email: [email protected]
Published on behalf of the European Society of Cardiology. All rights reserved. & The Author 2013. For permissions please email: [email protected].
1742
What’s new?
† Electrophysiology (ablation procedures and device therapy) is
mainly part of a cardiology department.
† Female invasive electrophysiologists are clearly underrepresented.
† A median number of 180 catheter ablations was performed
per centre.
† Atrial fibrillation was the most common arrhythmia invasively
treated.
† Only one-fourth of the electrophysiology centres fulfilled all
requirements for training centre accreditation according to
the European Heart Rhythm Association and the German
Cardiac Society.
quality require national and international standards, comprehensive
knowledge, as well as trained specialists in the field of cardiac electrophysiology. Therefore, it seems important to train young cardiologists in this field. To illustrate the importance of a structured
training programme for a ‘heart rhythm specialist’, the Accreditation
Committee of the European Heart Rhythm Association as well as national organizations such as the German Cardiac Society have recently published curricula for clinical electrophysiologists.2,3 These
curricula define requirements for training centres and trainees. In
view of this background, we thought that it would be of major interest
to find out the current status quo as the basis for future national and
international programmes. This knowledge could indicate how realistic training requirements are.
The purpose of this study was therefore to provide a nationwide
survey on cardiac electrophysiologists as well as types and
numbers of electrophysiological studies and ablations performed in
2010 in Germany. Furthermore, the study serves as the reference
for a planned second survey in 2015.
Methods
German cardiology centres performing invasive electrophysiology
were identified from (legally mandatory) quality reports of German
hospitals (http://www.dimdi.de/static/de/klassi/ops/anwendung/zweck/
qualitaetsberichte/index.htm). Hospitals with the following OPS (operation and procedure code) were identified: 8 –835.2 [radiofrequency
(RF) ablation], 8 – 835.3 (irrigated RF ablation), 8 – 835.4 (ablation with
other energy sources), 8 – 835.9 (MESH ablation), 8 – 835.a (cryoablation), and 8 –835.8 [ablation with three-dimensional (3D) mapping].
The number of OPS is not necessarily identical with the number of ablation procedures performed, because more than one OPS (e.g. irrigated
RF ablation plus ablation using 3D mapping) can be coded for a single ablation procedure. Regarding our survey and further analysis, centres
coding less than 30 ablation procedures were excluded. This cut-off
had been predefined because such a low number of coded ablation procedures increased the likelihood that the procedure itself was performed
in a different hospital or by an external electrophysiologist (employed,
e.g. at another hospital). The head of the cardiology department or of invasive electrophysiology was contacted by phone and/or e-mail to fill a
questionnaire. The following parameters were queried: type of hospital;
staff numbers and functions in cardiology and electrophysiology; gender
H.-R. Neuberger et al.
aspects; number of EP laboratories; number and types of EP procedures;
techniques used; imaging modalities; and presence of or distance to
cardiac surgery (for a detailed description see Table 1). Data were
made anonymous and send to a statistical centre. Descriptive statistics
were performed with SPSS version 15.0 (SPSS Inc.).
Results
According to OPS data, 277 centres coded ablation procedures in
2010. Among them were 88 centres that coded ,30 catheter ablation procedures. Of the remaining 189 centres coding ≥30 procedures, 122 (65%) responded. Their questionnaires were used for
analysis. Data came from 30 (25%) university hospitals, 71 (58%)
teaching hospitals (non-university hospitals involved in training of
medical students), 20 (16%) non-teaching hospitals, and one
private medical practice performing catheter ablations in a neighbouring hospital (1%, Figure 1).
The structure of invasive
electrophysiology
Electrophysiology (ablation procedures and device therapy) was
mainly part of a cardiology department (n ¼ 100 of 122, 82%), and
11 centres were independent (own budget, 9%). Invasive EP was
the main area of expertise of the head of the cardiology department
in another 11 centres (9%). At least one catheter laboratory was
almost exclusively (.90%) used for EP in 78 centres (64%),
whereas in the remaining centres (n ¼ 44, 36%) the EP lab was
used for non-EP procedures, too. In 12 centres (10%) at least two
dedicated EP laboratories were available. A three-dimensional
mapping system was present in 95 centres (77%).
In total, at the EP centres 26 864 pacemakers and 17 791
implantable cardiovert-defibrillators (ICD) were implanted in
2010. Device implantation was at least partly performed in a catheter laboratory in 87 of the centres (71%): always in 36 (30%),
most often (≥50%) in 17 (14%), and sometimes (,50%) in 34
(28%) of the centres. In the remaining 35 centres (29%) this was
done in the operating room. Devices were implanted by cardiologists in 67 (55%), by surgeons in 20 (16%), and by both in 35 (29%)
of the EP facilities.
Physicians involved in electrophysiology
Twelve (10%) of the 122 cardiology departments where ≥30 catheter ablations were performed had more than one head of department (e.g. head of invasive cardiology, head of electrophysiology,
etc.). In total, 149 heads of department (female: 3; 2%), 764 consultants (‘Oberarzt’, female: 109; 14%), and 2365 physicians in training
(female: 1044; 44%) were employed. In a majority of these centres
one (n ¼ 49, 40%) or two (n ¼ 40, 33%) EP consultants (‘Oberarzt’)
were employed. In 94 centres, EP consultants also performed coronary interventions (77%). No electrophysiology fellows in training
were present in 42 (34%) of the centres, one in 29 (24%), two in
19 (16%), and three or more in 32 (26%, Figure 2). In total, 193 EP consultants (19 females; 10%) were accompanied by 235 training positions (61 females; 26%), and the centres employed 315 physicians
(28 females; 9%) able to perform catheter ablations as primary operators (only 1 per centre in 30 centres; 25%). Of these, 122 (39%) were
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A survey of German centres performing invasive electrophysiology in 2010
Table 1 Questionnaire
Parameter
Options
Type of hospital
University, teaching, other, and private practice
Staffing of cardiology
Structure of Rhythmology
Staffing of Rhythmology
No. of heads, consultants (Oberärzte), physicians in training Male/female
Independent of cardiology, mostly independent (no budget), part of cardiology dpt.,
head of cardiology is heart rhythm specialist
No. of heads, consultants (Oberärzte), physicians in training Male/female
HR specialists performing PCI
Yes, partly, and no
HR specialists are cardiology
consultants
Yes, partly, and no
...............................................................................................................................................................................
Phys. performing ablations
No., gender, age, and part-time
EP recording systems
3D mapping system
No.
Yes, no
Cath. labs .90% used for EP
No.
Device implantation in EP lab
Phys. present during ablation
Always, ≥50%, ,50%, and no (operation room)
No.
Device implantation by
HR specialist, surgeon, and both
Pacemaker implantations
ICD implantations
No.
No.
Diagnostic EP procedures
No.
Catheter ablations
SVT
No.
No.
Main access left AP
Atrial flutter
Atrial fibrillation
Transseptal, aorta, and not done
No.
No.
Energy source
RF, Cryo, PVAC, and other
Imaging (mainly)
Sedation
CT, rotational angiography, MRI, and none
Intubation, analgo-sedation with / without propofol
Card. surgery backup
In-house, if not: distance in km
Treatment of secondary arrhythmias
VT
Main access LV
Yes, no
No.
Transseptal, aorta, and not done
Epicardial ablations
Pt. consent obtained ambulant
Yes, no
100%, ≥50%, ,50%, and ,10%
Surgical ablations
AF, VT, and none
No., number.
less than 40 years old, 152 (48%) were between 40 and 50 years old,
and 35 (11%) were older than 50 years (no data: 2%); 7 (2%) worked
part-time.
In only 71 (58%) of the centres, (at least) two physicians were
present during the majority of catheter ablations. The median
number of ablations per centre was 180 (Figure 3, upper panel). In
32 (26%) of the centres, ,100 ablations were performed, at least
200 catheter ablations were performed in 59 (48%). At least 50 AF
ablations were performed in 65 of the centres (53%, Figure 3, lower
panel).
Procedural data
In total, 40 735 EP procedures including 33 420 catheter ablations
were reported for 2010. Target arrhythmias (more than one type
of arrhythmia could be ablated in a single case) were regular SVT
(n ¼ 10 726; 32%), atrial flutter (n ¼ 8396; 25%), ventricular tachycardia (VT, n ¼ 2837; 8%), and AF (n ¼ 11 685; 35%, Figure 4). Ablation of left-sided accessory pathways was reported by 99 (81%) of
centres [no accessory pathway ablation in 10 (8%), no data available
for 13 centres (11%)] using either a trans-septal (n ¼ 55, 56%) or a
retrograde approach (n ¼ 44, 44%) as primary access. Left-sided
VT ablation was reported by 81 (66%) of EP centres [no VT ablation
in 27 (22%), no data from 14 centres, 11%]. The access to the left ventricle was primarily retrogradely via the aorta in 55 (68%) and via a
transseptal approach in 26 (32%) of the centres. In addition, epicardial
ablation was performed in 15 (19%) of these centres.
In total, 99 centres performed AF ablation procedures. As the
method for AF ablation, the majority of centres (n ¼ 89, 90%) used
point-by-point RF current, 50 (51%) used a cryoballoon (Arctic
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H.-R. Neuberger et al.
Centers performing invasive electrophysiology
University hospitals (25%)
Number of ablations performed in 2010 per center
2000
1800
1600
Private practice (1%)
1400
Non-teaching
hospitals (16%)
1200
1000
Teaching
hospitals
(58%)
800
600
400
200
Figure 1 Type of centres performing invasive electrophysiology
in Germany in 2010 and responding to the survey (n ¼ 122).
0
1
21
41
61
81
101
121
Number of AF ablations performed in 2010 per center
1400
1200
1000
Training positions for electrophysiologists / center
800
600
>3
(26%)
None
(34%)
400
200
50
0
2
(16%)
1
1
(24%)
Figure 2 Number of training positions per centre performing invasive electrophysiology.
Front, Medtronic Inc.), 21 (21%) a circular non-irrigated ablation
catheter (PVACw, Medtronic Inc.), and 7 (7%) other energy
sources. Imaging before AF ablation was routinely performed in 59
(60%) of centres [magnetic resonance imaging in 14 (14%), computed
tomography in 43 (43%), rotational angiography in 2 (2%) centres].
During AF ablation, patients were under general anaesthesia (tracheal intubation, n ¼ 6, 6%), or sedated with (n ¼ 54, 55%) or
without propofol (n ¼ 35, 35%). Consecutive left atrial arrhythmias
following AF ablations were treated by catheter ablation only in 74
(75%) of 99 centres performing AF ablation procedures. Only 44
(44%) of EP centres performing AF ablation had in-house surgical
backup. For the other centres, the distance to the next hospital performing cardiac surgery ranged from 2 to 100 km (median and mean:
20 and 31 km, respectively). Surgical ablations were performed in 41
(34%) of EP centres (surgical AF ablation: n ¼ 41, 34%; VT ablation:
n ¼ 10, 7%).
Patient consent for invasive EP procedures is obtained before hospital admission always in 22 (18%) of centres, most often (.50%) in
42 (34%), often (,50%) in 17 (14%), and rarely (,10%) in 41 (34%)
(In case of consent before admission, the EP study was performed on
the day of admission.).
21
41
61
81
101
121
Figure 3 Number of catheter ablations of any arrhythmia (upper
panel) and of AF (lower panel) are given per centre. The bold lines
(n ¼ 200 and 50, respectively) represent the minimal number of
procedures required for a heart rhythm specialist training centre
(Table 2).
Targets for catheter ablation
Supraventricular
tachycardias
(32%)
Ventricular
tachycardia
(8%)
Atrial fibrillation
(35%)
Atrial flutter
(25%)
Figure 4 Targets for catheter ablations (n ¼ 33 420). Atrial fibrillation was the most often treated arrhythmia.
Training centre requirements
Table 2 lists the requirements for training centre accreditation
according to the European Heart Rhythm Association and the
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A survey of German centres performing invasive electrophysiology in 2010
Table 2 Curriculum heart rhythm specialists: Training centre requirements and reality (Germany, 2010)
Parameter
EHRA
requirements
Centres fulfilling EHRA
requirements (n, %)
DGK
requirements
Centres fulfilling DGK
requirements (n, %)
...............................................................................................................................................................................
Physicians present during ablation
–
–
2
71 (58)
No. EP procedures/year
250
61 (50)
250
61 (50)
No. ablations/year
No. AF ablations/year
200
–
59 (48)
–
200
50
59 (48)
65 (53)
3D mapping system
Yes
95 (78)
Yes
95 (78)
Cardio surgical unit
All requirements
Yes
44 (36)
30 (25)
No
–
34 (28)
Requirements are defined according to guidelines and curricula as published.2 – 4
German Cardiac Society (DGK).2 – 4 About half of the centres
reported a number of procedures that fulfilled these criteria.
However, all requirements together were fulfilled by only one-fourth
of the centres.
Discussion
For the first time, this survey reports detailed data from the majority
of German centres that performed invasive electrophysiology in
2010. In total, two-thirds of the identified EP centres responded.
They carried out 33 420 catheter ablations that represent the majority (80%) of catheter ablations performed in Germany (41 913
diagnosis-related groups (DRGs) including a catheter ablation
(F50A, F50B, F50C, and F50D) were brought to account with
health insurance companies in 2010).5 The responding EP centres
carried out a minority of all pacemaker implantations (88.461 according to DRG data) and about every second ICD implantation in
Germany (35.329 according to DRG). Invasive electrophysiology is
performed in a relatively large number of hospitals; almost 200
centres were identified. For comparison, 556 institutions performed
845 172 coronary angiographies in 2008.6
The need for electrophysiological training will be high in the future.
For training in the subspecialty ‘Electrophysiology’, European and
German curricula have been published defining requirements for
physicians in training and for training centres (not legally binding). It
seems relevant to interpret our data with regard to this aspect.2,3
Based on the EHRA recommendation, an EP training centre should,
for example, employ at least two fully trained heart rhythm specialists
and needs to be integrated within a cardio-surgical unit (Table 2).
According to our data, only 36% of included centres would have fulfilled this criterion. Besides, 52% of the centres performed ,200
ablations a year, which is recommended by EHRA and DGK as a
minimum number for an EP training centre. In fact, only about onefourth of the EP centres fulfilled all training centre requirements.
These data illustrate the need for collaboration of EP centres to guarantee training standards and qualification. A highly specialized and
high-volume EP centre could offer a time period of intensive EP training. On the other hand, smaller centres could offer in exchange
broader training in cardiology and internal medicine for trainees
from highly specialized EP centres. This could improve clinical and scientific training for both cooperation partners and could make both
departments more attractive for trainees. Being aware that the
recommendations of the DGK advise the presence of two physicians
during catheter ablation it is remarkable that in 50 centres (41%) catheter ablations were performed only by one physician. Furthermore,
35% of the centres did not employ electrophysiology fellows. Thus,
a realistic chance of training in invasive electrophysiology does not
exist in a relevant proportion of the participating centres, even independent of curricular requirements.
In 2010, in the majority of centres clinical electrophysiology was
part of a cardiology department. Despite a high degree of subspecialization in cardiology and the increasing complexity of ablation
procedures (e.g. AF, ventricular tachycardia, and device therapy) only
about 10% of EP centres were independent. In this context, it is also
remarkable that the majority of EP consultants also performed coronary interventions. It will be of interest to observe the development
during the following years.
Although in 2010, women represented 62.6% of first-year medical
students,7 59.4% of physicians younger than 35 years, 50.6% of physicians 35 to less than 40 years old, and 44.1% of all physicians in
Germany,8 only 26% of physicians in EP training were female. Even
more accentuated was the low proportion of women among physicians able to perform catheter ablations as primary operator (9%).
This proportion was even lower than the proportion of female cardiology consultants (9 vs. 14%). We can only speculate about the
reasons. The extremely low proportion of female heads of departments, the duration of training, or radiation exposure during childbearing age may contribute. Furthermore, the option to work parttime in this field seemed almost not to exist. Research into this
field could offer a basis for attracting more women to this subspeciality.
Although in the early years of RF ablation regular SVTs and typical
atrial flutter were treated predominantly, the most common procedure in our survey in 2010 was AF ablation (36%). As one consequence, transseptal puncture has become a routine procedure in
most EP centres. This is probably the reason for a relatively frequent
transseptal access to left-sided accessory pathways (45%).This experience probably increases the safety of other trans-septal procedures (e.g. mitral valve interventions). On the other hand, VT
ablations were mainly performed retrogradely via the aorta.
Point-by-point RF current was the method most commonly used
for AF ablation. However, the high prevalence of other and less
1746
established technologies indicates the search (and need) for a more
rapid and effective method to treat AF. Given the high frequency of
the arrhythmia and its consequences, prospective AF ablation trials
with mortality as an endpoint are needed (e.g. the CABANA trial;
ClinicalTrials.gov identifier: NCT00911508). A positive result
would further increase the already growing demand for the procedure. It is surprising that a relevant proportion of centres performing
AF ablations do not treat consecutive left atrial arrhythmias (atypical
left atrial flutter).9 This probably indicates some mismatch between
the need for invasive AF treatment and the availability of experienced
EP specialists.
In-house cardiac surgery was available for only one-third of EP
centres. Remarkably, even EP centres performing AF ablation had
in-house surgical backup only in 44%. According to large surveys
cardiac tamponade is observed in about 1.3% of AF ablation procedures while surgical treatment is necessary in only a minority of
cases.10,11 However, every time delay to surgical intervention may
endanger the patient. The vast majority of cardiac surgery departments associated with EP centres performed surgical ablations
(mainly AF). Data on this topic are sparse, and the relative large
number of centres would offer the opportunity to investigate surgical
arrhythmia treatment on a large scale.
Limitations
Obviously, not all EP centres responded and possibly not all EP
centres were identified. However, our data cover the majority of
EP centres and procedures performed in 2010 in Germany. We do
neither have data on acute success of treatment nor follow-up
data. Our numbers rely on self-reporting. Thus, the results may not
exactly represent the number of procedures. In addition, two
thirds of the identified EP centres that responded reported 80% of
all DRG-coded catheter ablations. In consequence, smaller EP
centres are probably underrepresented. Furthermore, we excluded
centres coding ,30 ablation procedures in 2010 to prevent an overestimation of sites where catheter ablation is performed. As a result,
this survey may even over-estimate the number and percentage of
possible EP training centres fulfilling curricular requirements of
EHRA or DGK.
H.-R. Neuberger et al.
Summary
The results of this survey indicate an increasing specialization in cardiology and a high number of EP centres and procedures. Atrial fibrillation was the most common arrhythmia invasively treated in 2010 in
Germany. An increasing demand for catheter ablation is likely, but
training opportunities are limited. Women are clearly underrepresented in the field of invasive EP. Only a minority of EP centres fulfilled
recently suggested criteria for training centres. Training co-operation
of higher and lower volume EP centres may improve the number and
quality of training opportunities in both EP and cardiology.
Acknowledgements
We thank the nucleus of the working group ‘AG1 Rhythmologie’ of
the German Cardiac Society (speakers: C. W. Israel and D. Bänsch)
for collaboration. The authors received an unrestricted travel grant
from Biosense Webster, Norderstedt, Germany.
Conflict of interest: none declared.
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