<!--#set var="TITLE" value="Predicting Onset of Atrial Fibrillation"-->
<!--#include virtual="/head.shtml"-->
<center>Seth McClennen, MD<br>
Ary L. Goldberger, MD<br>
Beth Israel Deaconess Medical Center<br>
Boston, MA USA<br>
<br>
George B. Moody<br>
Harvard-MIT Division of Health Sciences and Technology<br>
Cambridge, MA USA<br>
</center>
<p>
The general objective of the <a href="/challenge/2001/">Computers in Cardiology
Challenge 2001</a> is to characterize changes in the surface electrocardiogram
immediately prior to the onset of paroxysmal atrial fibrillation (PAF), in an
effort to develop a reliable prediction algorithm for the arrhythmia.
<p>
Currently, no reliable validated methods exist to predict the onset of
PAF. Twelve-lead electrocardiograms <a href="#ref01">[1]</a>,
signal-averaged P-wave morphology <a href="#ref02">[2,3]</a>, R-R
interval dynamics <a href="#ref04">[4,5]</a>, and atrial ectopy <a
href="#ref05">[5-7]</a> have all been studied as possible predictors of
the onset of PAF. Sensitive and specific non-invasive markers
predicting the onset of PAF have not been determined or independently
validated, however. Given recent advances in clinical
electrophysiology, a prediction tool that would allow for detection of
imminent atrial fibrillation may have future therapeutic
ramifications.
<p>
Atrial fibrillation (AF) is the most common major cardiac arrhythmia.
In the United States alone, it affects an estimated 2.2 million
people, with an increasing prevalence in the elderly <a
href="#ref08">[8]</a>. As the population ages, the prevalence is
expected to rise; currently approximately 6% of the US population over
the age of 65 are diagnosed with this arrhythmia. Management consists
of heart rate control and/or prevention of recurrent fibrillation, as
well as prevention of secondary complications (most often
thromboembolism). Paroxysms of atrial fibrillation often precede the
onset of more sustained atrial fibrillation. A Japanese study of 234
patients with atrial fibrillation found that 94 (40%) had PAF, and
that sustained atrial fibrillation developed within one year in
approximately one fourth of patients with PAF <a
href="#ref09">[9]</a>.
<p>
The development of accurate predictors of the acute onset of PAF is
clinically important because of the increasing possibility of
electrically stabilizing and preventing the onset of atrial
arrhythmias with different atrial pacing techniques. Dual chamber
atrial pacing may reduce the heterogeneity of atrial refractoriness
manifested by P-wave duration changes on the surface electrocardiogram
recording. Preliminary studies by Prakash and colleagues <a
href="#ref10">[10]</a> have indicated that acute suppression of PAF is
possible in selected patients with dual-site right atrial pacing from
the coronary sinus ostium and high right atrium. The advances in
anti-tachycardia pacing, drug management, and defibrillation may be
applied to prevent the acute onset of PAF prior to the loss of sinus
rhythm. The maintenance of sinus rhythm can lead to decreased
symptoms, improved hemodynamics, and possibly a decrease in the atrial
remodeling that causes increased susceptibility to future episodes of
PAF <a href="#ref11">[11]</a>. In addition, there may be a reduction
in the risk of thromboembolic events.
<h3>References</h3>
<ol>
<a name="ref01"><li></a> Dilaveris PE, Gialafos, EJ, Sideris SK,
Theopistou AM, Andrikopoulos GK, Kyriakidis M, Gialafos JE, Toutouzas
PK. <a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9588401&dopt=Abstract"
target="other">Simple electrocardiographic markers for the prediction
of paroxysmal idiopathic atrial fibrillation</a>. Am Heart J
1998;135:733-738.
<a name="ref02"><li></a> Ishimoto N, Ito M, Kinoshita M. <a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10740152&dopt=Abstract"
target="other">Signal-averaged P-wave abnormalities and atrial size in
patients with and without idiopathic paroxysmal atrial
fibrillation</a>. Am Heart J 2000;139:684-689.
<a name="ref03"><li></a> Amar D, Roistacher N, Zhang H, Baum MS,
Ginsburg I, Steinberg JS. <a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10422924&dopt=Abstract"
target="other">Signal-averaged P-wave duration does not predict atrial
fibrillation after thoracic surgery</a>. Anesthesiology
1999;91:16-23.
<a name="ref04"><li></a> Vikman S, Makikallio TH, Yli-Mayry S,
Pikkujamsa S, Koivisto AM, Reinikainen P, Airaksinen KEJ, Huikuri HV.
<a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10562264&dopt=Abstract"
target="other">Altered complexity and correlation properties of R-R
interval dynamics before the spontaneous onset of paroxysmal atrial
fibrillation</a>. Circulation 1999;100:2079-2084.
<a name="ref05"><li></a> Hnatkova K, Waktare JEP, Murgatroyd FD, Guo
X, Baiyan X, Camm AJ, Malik M. <a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9630105&dopt=Abstract"
target="other">Analysis of the cardiac rhythm preceding episodes of
paroxysmal atrial fibrillation</a>. Am Heart J 1998;135:1010-1019.
<a name="ref06"><li></a> Kolb C, Nurnberger S, Ndrepepa G, Schreieck
J, Zrenner B, Karch M, Schmitt C. Modes of initiation of paroxysmal
atrial fibrillation: an analysis of 157 spontaneously occurring
episodes using 12-lead Holter monitoring. PACE 2000;23(4):607.
<a name="ref07"><li></a> Kolb C, Nurnberger S, Ndrepepa G, Zrenner B, Schomig
A, Schmitt C.
<a href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11676946&dopt=Abstract"
target="other">Modes of initiation of paroxysmal atrial fibrillation from
analysis of spontaneously occurring episodes using a 12-lead Holter monitoring
system</a>. Am J Cardiol 2001 Oct 15;88(8):853-7.
<a name="ref08"><li></a> Feinberg WM, Blackshear JL, Laupacis A,
Kronmal R, Hart RG. <a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7864703&dopt=Abstract"
target="other">Prevalence, age distribution, and gender of patients
with atrial fibrillation</a>. Arch Intern Med 1995;155:469-473.
<a name="ref09"><li></a> Takahashi N, Seki A, Imataka K, Fujii, J.
<a href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7230514&dopt=Abstract" target="other">
Clinical features of paroxysmal atrial fibrillation: an observation of
94 patients</a>. Jpn Heart J 1981;22:143-149.
<a name="ref10"><li></a> Prakash A, Saksena S, Hill M, Krol RB, Munsif
AN, Giorgberidze I, Mathew P, Mehra R. <a href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9120152&dopt=Abstract" target="other">Acute effects of dual-site
right atrial pacing in patients with spontaneous and inducible atrial
flutter and fibrillation</a>. J Am Coll Cardiol 1997;29:1007-1014.
<a name="ref11"><li></a> Prystowsky EN. <a
href="http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10822035&dopt=Abstract"
target="other">Management of atrial fibrillation: therapeutic options
and clinical decisions</a>. Am J Cardiol 2000;85:3D-11D.
</ol>
<!--#include virtual="/footer.shtml"-->
</body>
</html>