Register for email alerts and news feeds:
This journal | BMJ Group
rss
Heart 1998;80:251-256; doi:10.1136/hrt.80.3.251
Copyright © 1998 BMJ Publishing Group Ltd & British Cardiovascular Society

Heart 1998;80:251-256 ( September )

Prognostic significance of electrical alternans versus signal averaged electrocardiography in predicting the outcome of electrophysiological testing and arrhythmia-free survival

A A Armoundas,a D S Rosenbaum,bc J N Ruskin,c H Garan,c R J Cohena

a Harvard University -Massachusetts Institute of Technology Division of Health Sciences and Technology, Cambridge, Massachusetts, USA, b Departments of Medicine and Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA, c The Cardiac Unit, Massachusetts General Hospital, Boston, Massachusetts, USA

Correspondence to: Dr R J Cohen, Massachusetts Institute of Technology, E25-335, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. email: rjcohen{at}mit.edu

Accepted for publication 30 March 1998

Objective---To investigate the accuracy of signal averaged electrocardiography (SAECG) and measurement of microvolt level T wave alternans as predictors of susceptibility to ventricular arrhythmias.
Design---Analysis of new data from a previously published prospective investigation.
Setting---Electrophysiology laboratory of a major referral hospital.
Patients and interventions---43 patients, not on class I or class III antiarrhythmic drug treatment, undergoing invasive electrophysiological testing had SAECG and T wave alternans measurements. The SAECG was considered positive in the presence of one (SAECG-I) or two (SAECG-II) of three standard criteria. T wave alternans was considered positive if the alternans ratio exceeded 3.0.
Main outcome measures---Inducibility of sustained ventricular tachycardia or fibrillation during electrophysiological testing, and 20 month arrhythmia-free survival.
Results---The accuracy of T wave alternans in predicting the outcome of electrophysiological testing was 84% (p < 0.0001). Neither SAECG-I (accuracy 60%; p < 0.29) nor SAECG-II (accuracy 71%; p < 0.10) was a statistically significant predictor of electrophysiological testing. SAECG, T wave alternans, electrophysiological testing, and follow up data were available in 36 patients while not on class I or III antiarrhythmic agents. The accuracy of T wave alternans in predicting the outcome of arrhythmia-free survival was 86% (p < 0.030). Neither SAECG-I (accuracy 65%; p < 0.21) nor SAECG-II (accuracy 71%; p < 0.48) was a statistically significant predictor of arrhythmia-free survival.
Conclusions---T wave alternans was a highly significant predictor of the outcome of electrophysiological testing and arrhythmia-free survival, while SAECG was not a statistically significant predictor. Although these results need to be confirmed in prospective clinical studies, they suggest that T wave alternans may serve as a non-invasive probe for screening high risk populations for malignant ventricular arrhythmias.

Keywords: electrophysiological testing;  electrical alternans;  signal averaged electrocardiography;  arrhythmias


© 1998 by Heart

Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?

This article has been cited by other articles:

  • Narayan, S. M. (2006). T-Wave Alternans and the Susceptibility to Ventricular Arrhythmias. J Am Coll Cardiol 47: 269-281 [Abstract] [Full Text]  
  • Gehi, A. K., Stein, R. H., Metz, L. D., Gomes, J. A. (2005). Microvolt T-Wave Alternans for the Risk Stratification of Ventricular Tachyarrhythmic Events: A Meta-Analysis. J Am Coll Cardiol 46: 75-82 [Abstract] [Full Text]  
  • Walker, M. L, Rosenbaum, D. S (2003). Repolarization alternans: implications for the mechanism and prevention of sudden cardiac death. Cardiovasc Res 57: 599-614 [Abstract] [Full Text]  
  • Armoundas, A. A., Tomaselli, G. F., Esperer, H. D. (2002). Pathophysiological basis and clinical application of T-wave alternans. J Am Coll Cardiol 40: 207-217 [Abstract] [Full Text]  
  • Kitamura, H., Ohnishi, Y., Okajima, K., Ishida, A., Galeano, E., Adachi, K., Yokoyama, M. (2002). Onset heart rate of microvolt-level T-wave alternans provides clinical and prognostic value in nonischemic dilated cardiomyopathy. J Am Coll Cardiol 39: 295-300 [Abstract] [Full Text]  
  • ECTOR, H (1999). Prognostic significance of electrical alternans v signal averaged ECG in predicting the outcome of electrophysiological testing and arrhythmia-free survival. Heart 82: 534d-534 [Full Text]  

This Article

Services
Citing Articles
Google Scholar
PubMed
Topic Collections
Bookmark with

Register for free content

The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.

Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.