Measuring Electrical Resistance of Different Tissues on the Outer Surface of the Heart

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00291174
Recruitment Status : Terminated (Unforeseen difficulty identifying and enrolling eligible subjects)
First Posted : February 13, 2006
Last Update Posted : August 16, 2016
Biosense Webster, Inc.
Information provided by (Responsible Party):
University of Pennsylvania

Brief Summary:
This is a research study to evaluate the electrical properties of heart tissue. The purpose of this study is to determine the impedance (electrical resistance) of different tissues on the outer surface of the heart. This may be important for distinguishing scarred heart muscle from fat that can be seen on the surface of the heart. This information may eventually be utilized in patients that undergo a procedure (called catheter ablation) for the treatment of life-threatening heart rhythms. Investigators expect a detectable difference between the impedance of normal and infarcted myocardium (approximately 50 ohms).

Condition or disease
Cardiomyopathies Ventricular Dysfunction Myocardial Infarction Arrhythmia

Detailed Description:

The treatment of cardiac arrhythmias with endocardial catheter ablation has evolved rapidly over the past few decades. At the time of this writing, the ablation of almost all atrial and ventricular arrhythmias has been described in the literature. Multiple energy modalities (e.g. radiofrequency, cryotherapy) and approaches (e.g. retrograde aortic, transseptal puncture) have been described, yet ablation of some rhythms is not as successful as others.

The realization that ventricular tachycardia (VT) in the setting of Chagas Disease can originate in the epicardium has lead to the development of a percutaneous, transthoracic epicardial approach to mapping and ablation of this arrhythmia. This approach has now been applied to patients with VT in the setting of ischemic and nonischemic heart disease at many centers throughout the world. Traditional mapping technologies are utilized on the epicardium to define scarred heart tissue and locate the VT circuit.

It is well known that human hearts display a variable amount of fat overlying the epicardium. Not only is the coronary vasculature embedded in a layer of adipose tissue, but the rest of the heart may have areas of epicardial fat. As fat is an insulator and does not generate or easily conduct electrical activity, current mapping techniques may classify epicardial fat incorrectly as myocardial scar. This may have important effects on the ability to diagnose and treat arrhythmias with epicardial ablation.

Study Type : Observational
Actual Enrollment : 8 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Impedance Measurement of Epicardial Substrate for Ventricular Arrhythmias: Case Control Series of Patients With and Without Myocardial Scarring
Study Start Date : April 2006
Actual Primary Completion Date : July 2006
Actual Study Completion Date : January 2008

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Ages Eligible for Study:   18 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Adult patients undergoing elective cardiac surgery for coronary artery disease

Inclusion Criteria:

  • All adult patients undergoing elective cardiac surgery for coronary artery disease (with or without normal heart function) or valvular disease (with normal heart function) at the Hospital of the University of Pennsylvania under the direction of Y. Joseph Woo MD will be eligible.

Exclusion Criteria:

  • Patients undergoing emergent surgery and patients with idiopathic cardiomyopathy, infiltrative cardiomyopathies and hypertrophic cardiomyopathies will be excluded.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00291174

United States, Pennsylvania
Hospital of the University of Pennsylvania
Philadelphia, Pennsylvania, United States, 19104
Sponsors and Collaborators
University of Pennsylvania
Biosense Webster, Inc.
Principal Investigator: David J. Callans, MD University of Pennsylvania, Dept of Medicine, Cardiology Division


Responsible Party: University of Pennsylvania Identifier: NCT00291174     History of Changes
Other Study ID Numbers: 803272
First Posted: February 13, 2006    Key Record Dates
Last Update Posted: August 16, 2016
Last Verified: August 2016

Keywords provided by University of Pennsylvania:
Ventricular Arrhythmia
Myocardial Infarction
Ventricular Dysfunction
Coronary Artery Disease
Structural Heart Disease

Additional relevant MeSH terms:
Myocardial Infarction
Ventricular Dysfunction
Pathologic Processes
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Vascular Diseases