T-wave Alternans and Intrathoracic Impedance Measurements

Congestive Heart Failure Clinical Trial

Official title:

T-wave Alternans and Intrathoracic Impedance Measurements

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00669682
• Other study ID #: AAAC5529
• Status: Completed
• Phase: N/A
• First received: April 28, 2008
• Last updated: April 11, 2013
• Start date: August 2008
• Est. completion date: April 2012

Study information

• Verified date: April 2013
• Source: Columbia University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

T-wave alternans is a test that is currently being used to risk stratify patients with structural heart disease for sudden cardiac death. The mechanism of T-wave alternans is unclear, but may share a common abnormality with conditions of cardiac fluid overload such as heart failure, which is altered intracellular calcium handling. Current Medtronic implantable defibrillators have the capability of monitoring cardiac fluid status via transthoracic impedance measurements.

The purpose of this study is to determine if a correlation exists between T-wave alternans status and cardiac volume status, as determined by transthoracic impedance measurements. Secondarily, the study seeks to examine the relationship between arrhythmia frequency and T-wave alternans or cardiac volume status.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 9
• Est. completion date: April 2012
• Est. primary completion date: April 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Class III or IV heart failure patients with a chronically implanted Medtronic biventricular defibrillator system capable of monitoring intrathoracic fluid volume.

Exclusion Criteria:

• no active ischemia or pulmonary edema, atrial fibrillation, complete heart block

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Arrhythmias
• Congestive Heart Failure
• Heart Failure

Intervention

Other:
• Congestive heart failure
Spontaneous occurrence of fluid overload.

Locations

Country	Name	City	State
United States	Columbia University Medical Center	New York	New York

Sponsors (2)

Lead Sponsor	Collaborator
Columbia University	Medtronic

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of Positive Twave Studies and Concurrent Positive Optivol Measurement	We wanted to examine whether positive Optivol status corresponded to a higher likelihood of a positive T wave study. The T wave alternans result is determined by a proprietary device that measures T wave and reports the result as negative, positive, or indeterminate. The Optivol measurement is obtained through transthoracic impedance values in the implanted device. We investigated the correlation between Optivol status and T wave alternans status.	upto 3 years	No