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Prognostic Significance of T Wave Alternans

This study has been completed.
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Columbia University Identifier:
First received: November 16, 2000
Last updated: December 21, 2015
Last verified: December 2015

To evaluate whether T Wave Alternans can predict ventricular arrhythmias and sudden cardiac death (SCD) in a prospective epidemiologic natural history study.

The prospective epidemiologic pilot study included 550 patients that had left ventricular dysfunction and no history of sustained ventricular arrhythmias. The primary hypothesis tested was whether there was an increased risk of having an arrhythmic event when T Wave Alternans was present in the patient. The secondary aims included comparing risk due to T Wave Alternans between the ischemic patients and non-ischemic patients and assessing whether T Wave Alternans remained an independent predictor of risk upon adjustment for other known risk factors for arrhythmic events such as ejection fraction, ventricular ectopy, NSVT, average NN interval, and RR interval variability.

The study approach was a standard epidemiologic surveillance technique. The subject population consisted of individuals with Class I to III heart failure who will underwent a TWA and Holter monitor test and then were followed for up to two years or until arrhythmic events occured.

Condition Intervention
Heart Diseases
Ventricular Arrhythmia
Ventricular Fibrillation
Death, Sudden, Cardiac
Heart Arrest
Procedure: ECG

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: The Prevalence and Prognostic Significance of T Wave Alternans in Patients With Severe Congestive Heart Failture

Resource links provided by NLM:

Further study details as provided by Columbia University:

Primary Outcome Measures:
  • Pevalence of SCD with earlier testing that indicated TWA [ Time Frame: Up to 24 months ]

Enrollment: 549
Study Start Date: January 2003
Study Completion Date: February 2012
Primary Completion Date: December 2009 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
ECG recording
After the tests are completed, people who enroll in this study are followed by telephone, 1, 4, 8, 12 16, 20 and 24 months. During these follow-up telephone calls a research coordinator asks about the participant's health condition and about cardiovascular medications that are being taken.
Procedure: ECG
A diagnostic tool that is routinely used to assess the electrical and muscular functions of the heart (non-experimental).
Other Name: Electrocardiogram

Detailed Description:

Sudden cardiac death accounts for approximately 400,000 deaths each year in the United States and remains a health problem of epidemic proportions. Most sudden cardiac deaths are caused by fatal ventricular arrhythmias. An effort aimed at the primary prevention of sudden cardiac death requires efficient identification of patients who are at high enough risk for having these arrhythmias to warrant aggressive prophylactic therapy. A number of recently completed, randomized clinical trials have demonstrated that an implantable cardiac defibrillator (ICD) can prevent sudden cardiac death in a highly selected group of high-risk patients. When these trials are viewed together, the only patients in whom the prophylactic implantation of an ICD has proven benefit are those patients identified by documented, spontaneous or inducible, sustained ventricular arrhythmias.

Two randomized treatment trials (MADIT II, SCD-HEFT) tested the hypothesis that implantation of an ICD would reduce mortality in patients with congestive heart failure (CHF) and left ventricular dysfunction without any further risk tratification. However, the implications of these two trials-implantation of an ICD in every patient with CHF-were unlikely to be accepted either by the medical community or by health care payers. More efficient methods of risk stratification were necessary to identify those patients with CHF who were most likely to benefit from prophylactic treatment with an ICD.

T Wave Alternans is a subtle every-other-beat variation in electrocardiographic T waves that is prognostic of patients at high risk for life-threatening cardiac arrhythmias and sudden cardiac death. It has recently been shown that T Wave Alternans (TWA) measured during exercise is strongly associated with inducible monomorphic CVT and with subsequent spontaneous arrhythmic events. This preliminary data suggest that TWA may be an efficient and non-invasive surrogate for electrophysiologic testing to screen patients who may be at high-risk for sudden cardiac death.


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patients with left ventricular dusfunction or non-ischemic cardiomyopathy, and are at high risk for sudden cardiac death.

Inclusion Criteria

  1. Patients with left ventricular dusfunction
  2. Patients with non-ischemic cardiomyopathy

Exclusion Criteria

1. Patients not at high risk for sudden cardiac death (SCD)

  Contacts and Locations
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Please refer to this study by its identifier: NCT00006501

United States, New York
Columbia University
New York, New York, United States, 10023
Sponsors and Collaborators
Columbia University
National Heart, Lung, and Blood Institute (NHLBI)
Principal Investigator: John Bigger Professor Emeritus of Medicine and Pharmacology, Columbia University
Principal Investigator: John Bigger Columbia University
  More Information

Responsible Party: Columbia University Identifier: NCT00006501     History of Changes
Other Study ID Numbers: AAAB1399
R01HL064862 ( US NIH Grant/Contract Award Number )
Study First Received: November 16, 2000
Last Updated: December 21, 2015

Additional relevant MeSH terms:
Heart Diseases
Death, Sudden
Death, Sudden, Cardiac
Heart Arrest
Ventricular Fibrillation
Cardiovascular Diseases
Pathologic Processes
Arrhythmias, Cardiac processed this record on April 25, 2017