This document provides a critique of the ACCF/AHA Scientific Statement on Syncope. It was submitted by a consortium of over 60 physicians with expertise in transient loss of consciousness. The consortium has concerns that the Scientific Statement fails to adequately address long-standing clinical errors in syncope evaluation, provides imprecise definitions, omits important recent literature, and does not present the evaluation of syncope in full clinical context. If not revised, the Scientific Statement risks promoting inadequate patient care and potentially harmful legal standards for physicians.

1. The ACCF/AHA Scientific Statement on Syncope:
a document in need of thoughtful revision
David G. Benditt on behalf of the Ad Hoc Syncope Consortium{
Cardiovascular Division, Cardiac Arrhythmia Center, University of Minnesota Medical School, Mail Code 508,
420 Delaware St SE, Minneapolis, MN 55455, USA
Received 26 July 2006; accepted after revision 22 August 2006
The American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) have
recently published, in both the Journal of the American College of Cardiology (JACC) and Circulation, a
Scientific Statement on the Evaluation of Syncope (‘Statement’). This Scientific Statement was commis-
sioned to provide guidance for clinicians regarding the evaluation of patients who present with
‘syncope’. The Statement was not intended to be a formal set of practice guidelines. However, in
the absence of generally accepted practice guidelines in North America, the Statement’s potential
impact on clinical care may be more far-reaching than expected; it may erroneously be considered
to be the authoritative ‘de-facto’ guideline document. This commentary, submitted by a multidisciplin-
ary consortium of more than 60 physicians with expertise in the management of transient loss of
consciousness (TLOC), points out that in many respects the ACCF/AHA Syncope Statement fails to
address long-standing clinical errors associated with the evaluation of episodes of apparent TLOC,
including syncope. If not appropriately revised, the current Statement may lead to both inadequate
patient care as well as a potentially damaging legal environment for physicians undertaking evaluation
of patients who present with transient loss of consciousness.
KEYWORDS
Syncope;
Practice guidelines;
Diagnosis;
Evaluation;
Management
Introduction
Recently, the American College of Cardiology Foundation
(ACCF) and the American Heart Association (AHA) published,
in both Journal of the American College of Cardiology
(JACC) and Circulation, a scientific statement on the evalu-
ation of syncope (‘statement’).1
This scientific statement
was commissioned to provide guidance for clinicians regard-
ing the evaluation of patients who present with ‘syncope’.
The ACCF/AHA statement was not intended to be a formal
set of practice guidelines. Nonetheless, in the absence of
formal practice guidelines endorsed by professional
societies in North America, the statement’s impact on clini-
cal care may be far-reaching. In fact, given its carrying the
imprimatur of the ACCF, the AHA, and the Heart Rhythm
Society, the statement may be erroneously considered to
be the authoritative de facto guideline document.
The Ad Hoc Syncope Consortium is a multidisciplinary
group of more than 60 physicians with expertise in the
management of patients presenting with transient loss of
consciousness (TLOC), including syncope. The consortium
formed primarily as a result of its individual members
having identified important concerns with the ACCF/AHA
syncope statement. Apart from alerting readers to the
syncope statement’s shortcomings, the consortium’s goals
are to support thoughtful revision of the syncope statement
and to promote development of guidelines for management
of patients with TLOC that takes into account the multifa-
ceted nature of the problem. To this end, the Ad Hoc
Consortium has published a commentary regarding the
syncope statement on Heart.org and a brief letter addres-
sing some of our concerns with the statement in JACC.
Circulation has declined publishing any critique of the
statement.
In the consortium’s opinion, the ACCF/AHA syncope state-
ment does not adequately address many long-standing clini-
cal errors associated with the evaluation of episodes of
apparent self-limited TLOC, including syncope. In addition,
the statement’s messages and conclusions are often impre-
cise and seem to lack balance. Although, in some instances,
our disagreements with the statement’s positions may simply
reflect honest differences of opinion, there are clear-cut
oversights in the statement that deserve attention. Several
important shortcomings are highlighted subsequently.
& The European Society of Cardiology 2006. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org
Corresponding author. Tel: þ1 612 625 4401; fax: þ1 612 624 4937.
E-mail address: bendi001@umn.edu
{
The list of co-authors belonging to the AD Hoc Syncope Consortium is
given in the appendix.
Europace (2006) 8, 1017–1021
doi:10.1093/europace/eul134

2. Proper definitions
Clinicians need clear, practical, and accurate definitions of
syncope and related terminology before they can begin
their diagnostic evaluation. The ACCF/AHA statement does
not provide accurate definitions. For instance, it is critical
in our opinion that a document focusing on the syncope evalu-
ation addresses the fundamental issue, ‘what is syncope?’.
The statement’s approach is inadequate; it does not establish
the distinction between syncope and the broader problem of
TLOC.2–4
For the statement to be useful, it must address what
syncope is and how it differs from other forms of TLOC (e.g.
concussion due to trauma, epileptic seizures due to a
primary electrical problem, and apparent TLOC such as in con-
version disorders). To be fair, failure to distinguish syncope
from other forms of TLOC is an error,5
which is also found in
other prominent medical writings.6,7
The absence of clarity regarding the central topic of
the statement’s interest only serves to aggravate other
long-standing misunderstandings. By way of example, the
statement itself continues to foster the misconception that
‘vasovagal’ and ‘neurocardiogenic’syncopes are synonymous.
The former is, in fact, a subset of the neurocardiogenic
faints (the preferred term being neurally mediated reflex
faints 8
). This may appear to be a minor point, and certainly
elimination of all errors is not a reasonable expectation, but
it is indicative of the need for careful and critical review of
statements from professional societies prior to publication.
The consequence of imprecise definitions is propagation
of unclear thinking among clinicians. The outcome is uncer-
tainty leading to excessive and generally futile overuse of
inappropriate medical tests.9–12
The statement missed an
opportunity to rectify this major problem; one that leads
to unnecessary costs and possible patient harm.
Absence of citations to many published
contemporary statements and documents
The ACCF/AHA statement offers as a goal ‘to summarize the
data that direct the evaluation of the patient with syncope’.
However, the statement fails to cite important recent
contributions to the syncope evaluation. Most importantly,
the European Society of Cardiology (ESC) Syncope
Guideline statements8,13
published in 2001 and revised in
2004 are missing. In this regard, a number of Consortium’s
members (Ã
) admit a potential conflict of interest, having
participated in the ESC guideline development.
Contrary to the preferred current practice in which the
best available medical evidence is used to support clinical
recommendations, the statement ignores the majority of
recently published controlled trials in the field. For
instance, although the statement’s authors cite three ICD
trials14–16
and one drug trial,17
none of which focused
primarily on a syncope population per se, they only
reference a single non-ICD trial that did enroll true
syncope patients.18
Further, the authors failed to cite
either of the two major North American pacing trials
targeting syncope patients (VPS-1 and VPS-219,20
), or the
single large beta-blocker trial (POST21,22
), or the only trial
examining the utility of an organized syncope management
unit in a North American hospital (SEEDS23
). Moreover, the
current statement omits citing any of the several European
randomized and/or controlled clinical trials that assessed
various aspects of the syncope evaluation, and several of
which were published in the North American journals. With
the exception of the citation of SAFE-PACE,24
published
clinical trials such as EGSYS,25
OESIL,26
OESIL2,27
ISSUE-1,28–30
ISSUE-2,31
VASIS,32,33
SYDIT,34
and SYNPACE35
were not referenced.
It is true that the statement was commissioned to focus on
‘evaluation’ (not on treatment) and apparently had space
limitations that may have precluded citing all pertinent
literatures. Further, many, but not all, of the missing cita-
tions examined aspects of syncope treatment rather than
diagnostic evaluation. In contrast, it is impractical to try to
divorce evaluation and treatment completely. All of the pub-
lished studies provide important insights into the optimal
evaluation process. Indeed, many of the studies that were
cited in the statement were no less treatment-oriented
than were the multitude of studies that were omitted.
The rationale for the evaluation of syncope
is not solely to provide a mortality risk
assessment
According to the statement, the primary ‘purpose of the
(syncope) evaluation’ is ‘to determine whether the patient
is at increased risk for death’. We agree that mortality risk
assessment is a valid concern. However, the vast majority
of these patients has disturbing or disabling condition,
which is not life threatening, but may diminish quality of
life and lead to physical injury.2,6,36–40
Consequently, the
rationale for the syncope evaluation should be a more fun-
damental one, namely, to establish the cause of the
patient’s symptoms with sufficient confidence to assess
prognosis and recommend an effective treatment
strategy.8,13,36,37
Appropriate clinical perspective
The statement focuses on the relatively small, albeit
important, subset of high-risk patients (at most 20% of
those with syncope) who may require treatment with cardio-
vascular interventions such as implantable cardioverter-
defibrillators (ICDs) or pacemakers. However, thoughtful
consideration of far more prevalent causes of syncope,
namely, those of neurally mediated reflex or orthostatic
origin, are hardly addressed.36,37,39–42
These latter con-
ditions account overall for more than half of all syncope
cases, although rarely life-threatening can result in substan-
tial morbidity. Furthermore, certain types of faints (e.g.
vasovagal syncope and situational faints) are particularly
important in children and young adults. The relevance of
patient age to the syncope evaluation process (i.e. the like-
lihood of one or other form of syncope being more or less
probable) is inadequately addressed in the statement. The
fact that neurally mediated and orthostatic fainting con-
ditions have been the subject of many recent published
studies and reviews36,37,40–52
does not exempt the state-
ment from providing practitioners with an appropriate
perspective on the problem.
Even regarding ICD and pacemaker therapies, the state-
ment lacks a comprehensive and carefully defined approach.
Specifically, the statement does not provide practitioners
with sufficient depth of insight into the appropriate
1018 Editorial Comment

3. circumstances and limitations of ICD or pacemaker utiliz-
ation in syncope patients. For instance, although ICDs may
prevent arrhythmic death, they may not alleviate syncope.
This vital aspect of the treatment of the high-risk fainter
is a common dilemma in patients with structural heart
disease, as well as in individuals with less common con-
ditions such as long QT syndrome and Brugada syndrome. It
remains unexplored in the statement.
In the case of syncope patients with normal hearts, the
statement underemphasizes the importance of a thorough
evaluation. The statement implies that aggressive diagnostic
effort is only needed in the most severe (‘malignant’) forms
of syncope, where ‘malignant’ is ‘defined as an episode of
syncope that occurs with little or no warning and results in
significant injury or property damage’. This teaching unfor-
tunately tends to diminish the importance of symptoms in
the vast majority of fainters, individuals who we know
have substantially reduced quality of life,53
and who may
be at future risk of injury, accident, or economic loss
because of occupational issues.
The statement should encourage effective diagnostic
assessment in all types of syncope patients. Beyond ICDs
and pacemakers, clinicians should be made aware of evol-
ving treatment options for vasovagal fainters, or patients
with orthostatic hypotension, including those suffering
from various dysautonomias.43–51
A revised statement should incorporate a more thoughtful
assessment of the important role that medical specialists
outside the cardiovascular disease arena play in the evalu-
ation of TLOC/syncope. Neuroscience, internal medicine,
paediatrics, and geriatric specialties, among others, con-
tribute daily to the care of patients who present with appar-
ent loss of consciousness spells. Without input from leaders
in these fields, recommendations for the syncope evalu-
ation, such as those provided in the ACCF/AHA statement,
cannot be considered complete and credible.
In conclusion, we would like to emphasize our concern
that the current ACCF/AHA statement may be mistakenly
construed as an authoritative text. In the absence of a well-
considered set of practice guidelines, the statement could
unfortunately become an inappropriate ‘standard’ for all
syncope evaluations in the USA and Canada. As such, its
current contents may lead to both less than optimal
patient care and a potentially damaging legal environment
for physicians undertaking the evaluation of patients who
present with TLOC. It is clear that development of interna-
tionally applicable multidisciplinary formal practice guide-
lines must receive high priority.
Appendix
Wouter Wieling
Academic Medical Centre, University of Amsterdam, Amsterdam,
The Netherlands
Haruhiko Abe
The Second Department of Internal Medicine,University of
Occupational and Environmental Health, Yahatanishi, Kitakyushu
807-8555, Japan
Paolo Alboni
Divisione di Cardiologia, Ospedale Civile, Cento, Italy
Dietrich Andresen
Direktor der Klinik fu¨r Innere Medizin-Kardiologie/Angiologie/
konserv, Intensivmedizin, Vivantes-Klinikum Am Urban/Im
Friedrichshain 10 967, Berlin
Felicia B. Axelrod
New York University School of Medicine, Carl Seaman Family
Professor of Dysautonomia Treatment and Research, Pediatrics,
NYU Medical Center, New York, NY, USA
Eduardo Bennaroch
Department of Neurology, Mayo Medical School, Mayo Clinic,
Rochester, MN, USA
Lennart Bergfeldt
Department of Cardiology, Sahlgrenska Academy, University of
Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden
Jean Jacques Blanc
Departement de Cardiologie, Universite de Brest, Hopital de la
Cavale Blanche, CHU de Brest, France
Michele Brignole
Department of Cardiology and Arrhythmologic Centre, Ospedali
del Tigullio, 16033 Lavagna, Italy
A. John Camm
St George’s Medical School of London, Cranmer Terrace, London, UK
Thomas Chelimsky
Case Western Reserve University, American Academy of
Neurology, University Hospitals of Cleveland, Cleveland, OH, USA
Pietro Cortelli
Alma Mater Studiorum-Universita’di Bologna, Dipartimento di
Scienze Neurologiche, 40123 Bologna, Italy
J. Gert van Dijk
Department of Neurology and Clinical Neurophysiology, Leiden
University Medical Centre, Leiden, The Netherlands
Nynke van Dijk
Academic Medical Centre, University of Amsterdam, Amsterdam,
The Netherlands
Murray Esler
Monash University, Melbourne, Australia
Baker Heart Research Institute, Melbourne, Victoria 8008,
Australia
Adam Fitzpatrick
Manchester Heart Centre, Royal Infirmary, Manchester, UK
Fetnat Fouad-Tarazi
Department of Cardiology, Cleveland Clinic Foundation,
Cleveland, OH, USA
Roy Freeman
Harvard Medical School, Center for Autonomic and Peripheral
Nerve Disorders, Beth Israel Deaconess Medical Center, Boston,
MA, USA
MaryAnn Goldstein
Pediatric Emergency Medicine, Minneapolis, MN, USA
Blair Grubb
Medical College of Ohio, Toledo, OH, USA
Bengt Herweg
University of South Florida, Tampa, FL, 33606, USA
Max J. Hilz
Department of Neurology, University Erlangen-Nuremberg,
Erlangen, Germany
American Academy of Neurology, New York University School of
Medicine, New York, NY, USA
Giris Jacob
Rambam Medical Center and Technion IIT, Hiafa, Israel
David Jardine
Christchurch School of Medicine, University of Otago,
Christchurch, New Zealand
Jens Jordan
Franz-Volhard Centrum fu¨r Klinische Forschung, 13125 Berlin,
Germany
Michael J. Joyner
Mayo Clinic, Rochester, MN, USA
Wishwa Kapoor
Department of Internal Medicine, University of Pittsburgh,
Pittsburgh, PA, USA
Horacio Kaufmann
Mount Sinai School of Medicine, New York, NY, USA
Editorial Comment 1019

4. Rose-Anne Kenny
Institute of Neuroscience, Trinity College, Dublin 2, Ireland
Institute for the Health of the Elderly, University of Newcastle
Upon Tyne, Royal,Victoria Infirmary, Newcastle upon Tyne, UK
Andrew Krahn
Arrhythmia Monitoring Unit, London Health Sciences Centre,
University of Western Ontario, London, Ontario, Canada
Chu-Pak Lau
Department of Medicine, Hong Kong University and Queen Mary
Hospital, Hong Kong, China
Benjamin D. Levine
Division of Cardiology, Department of Internal Medicine,
University of Texas Southwestern Medical Center at Dallas, TX
75231, USA
Johannes J. van Lieshout
Department of Internal Medicine, Academic Medical Centre,
University of Amsterdam, Amsterdam, The Netherlands
Lewis Lipsitz
Hebrew Senior Life Institute for Aging Research, Boston, MA,
USA
Philip Low
Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, USA
Keith G. Lurie
University of Minnesota Medical School and Central Minnesota
Heart Center,
Hennepin County Hospital, Minneapolis, MN, USA
St Cloud Hospital, St Cloud Minnesota, USA
Christopher J. Mathias
Neurovascular Medicine Unit, Faculty of Medicine, Imperial
College London at St Mary’s Hospital, The Queen Elizabeth, The
Queen Mother Wing, London W2 1NY, UK
Autonomic Unit, National Hospital for Neurology and
Neurosurgery, Queen Square and Institute of Neurology, University
College London, London WC1 N 3BG, UK
Angel Moya
Department of Cardiology, Hospital General Vall d’Hebron, 08035
Barcelona, Spain
Brian Olshansky
University of Iowa Medical School, Iowa City, IA, USA
Satish R. Raj
Vanderbilt University, Nashville, TN, USA
Antonio Raviele
Divisione di Cardiologia, Ospedale Umberto I, Mestre-Venice, Italy
Sanjeev Saksena
Robert Wood Johnson Medical School, Millburn, NJ, USA
Francois P. Sarasin
Hopital Cantonal, University of Geneva Medical School, 1211
Geneva 14, Switzerland
Philip J. Saul
Medical University of South Carolina, Charleston, SC, USA
Ronald Schondorf
Department of Neurology McGill University, SMBD Jewish General
Hospital, Montreal, Quebec, Canada
Jean-Michel Senard
School of Medicine, University of Toulouse III, Faculte´ de
Me´decine, 31000 Toulouse, France
Robert Sheldon
Libin Cardiovascular Institute of Alberta, University of Calgary,
Calgary, Alberta, Canada
Win-Kuang Shen
Mayo Medical School, Mayo Clinic, Rochester, MN, USA
Jasbir Sra
University of Wisconsin- Milwaukee, Milwaukee, WI, USA
John Stephenson
Fraser of Allander Neurosciences Unit, Royal Hospital for Sick
Children, Glasgow G3 8SJ, Scotland
Division of Developmental Medicine, University of Glasgow,
Scotland
Julian M. Stewart
Center for Hypotension, New York Medical College, Hawthorne,
NY 10532, USA
Richard Sutton
Royal Brompton Hospital, London, UK
Hidetaka Tanaka
Department of Developmental Pediatrics, Osaka Medical College
Hospital, Osaka 569-8686, Japan
George Theodorakis
28 Department of Cardiology, Onassis Cardiac Surgery Center,
Athens, Greece
Andrea Ungar
Department of Critical Care Medicine and Surgery—Unit of
Geriatrics and Gerontology, University of Florence, 50141
Florence, Italy
A.A.M. Wilde
Department of Cardiology, Academic Medical Center Amsterdam,
1105 AZ Amsterdam, The Netherlands
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Editorial Comment 1021