FUSTER
ET AL., ACC/AHA/ESC GUIDELINES FOR THE MANAGEMENT OF
PATIENTS WITH ATRIAL FIBRILLATION
J Am Coll Cardiol 2001;38:1266i-1xx
ACC/AHA/ESC
Guidelines for the Management of Patients with Atrial
Fibrillation
III.
Classification
AF
has a heterogeneous clinical presentation, occurring
in the presence or absence of detectable heart disease
or related symptoms. Various classification systems
have been proposed for AF. One scheme is based on the
ECG presentation (1-3).
Another is based on epicardial (5)
or endocavitary recordings or noncontact mapping of
atrial electrical activity. Several clinical classification
schemes have also been proposed, but none fully accounts
for all aspects of AF (6-9).
To be clinically useful, a classification system must
be based on a sufficient number of features and carry
specific therapeutic implications.
An
episode of AF may be self-limited or require medical
intervention for termination. Over time, the pattern
of AF may be defined in terms of the number of episodes,
duration, frequency, mode of onset and possible triggers,
and response to therapy, but these features may be impossible
to discern when AF is first encountered in an individual
patient. Although the pattern of the arrhythmia can
change over time, it may be of clinical value to characterize
the arrhythmia at a given moment.
Assorted
labels have been used to describe the pattern of AF,
including acute, chronic, paroxysmal, intermittent,
constant, persistent, and permanent, but the vagaries
of definitions make it difficult to compare studies
of AF in terms of the effectiveness of therapeutic strategies
based on these designations. The classification scheme
recommended in this document represents a consensus
driven by a desire for simplicity and clinical relevance.
The
clinician should distinguish a first-detected episode
of AF, whether or not it is symptomatic or self-limited,
recognizing that there may be uncertainty about the
duration of the episode and about previous undetected
episodes (Figure 3). When
a patient has had 2 or more episodes, AF is considered
recurrent. If the arrhythmia terminates spontaneously,
recurrent AF is designated paroxysmal; when sustained,
AF is designated persistent. In the latter case, termination
with pharmacological therapy or electrical cardioversion
does not change the designation. Persistent AF may be
either the first presentation of the arrhythmia or the
culmination of recurrent episodes of paroxysmal AF.
The category of persistent AF also includes cases of
long-standing AF (e.g., greater than 1 year) in which
cardioversion has not been indicated or attempted, usually
leading to permanent AF (Figure
3).
The
terminology defined in the preceding paragraph applies
to episodes of AF that lasts more than 30 seconds and
that are unrelated to a reversible cause. Secondary
AF that occurs in the setting of acute myocardial infarction
(MI), cardiac surgery, pericarditis, myocarditis, hyperthyroidism,
pulmonary embolism, pneumonia, or acute pulmonary disease
is considered separately, because AF is less likely
to recur once the precipitating condition is resolved.
In these settings, AF is not the primary problem, and
treatment of the underlying disorder concurrently with
management of the episode of AF usually results in termination
of the arrhythmia without recurrence.
The
term "lone AF" has been variously defined
but generally applies to young individuals (under 60
years of age) without clinical or echocardiographic
evidence of cardiopulmonary disease (10).
These patients have a favorable prognosis with respect
to thromboembolism and mortality. As time goes by, however,
patients move out of the lone AF category by virtue
of aging or the development of cardiac abnormalities
such as enlargement of the left atrium (LA), and the
risks of thromboembolism and mortality rise accordingly.
Lone AF is distinguished from other forms of idiopathic
AF because of the criteria of patient age and the absence
of identified cardiovascular pathology. By convention,
the term nonvalvular AF is restricted to cases in which
the rhythm disturbance occurs in the absence of rheumatic
mitral valve disease or a prosthetic heart valve.
Copyright
© 2001 by the American College of Cardiology, American
Heart Association, Inc., and the European Society of
Cardiology
Published by Elsevier Science Inc.
|
