Dynamic Thoracic Impedance as a Marker for Heart Failure Decompensation

Study Overview
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Brief Summary
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This pilot study proposes to perform measurements of approved thoracic impedance technology that will help answer questions in patients with decompensated heart failure.

Detailed Description
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Improved metrics derived from the transthoracic impedance (Z) available from implanted Medtronic devices may provide more sensitive indicators of the state of compensation for heart failure patients. Quantification of specific data may provide new information that can improve quality of life for patients and offer vital information to clinicians regarding the adequacy of inpatient and outpatient assessment and management of acute decompensated heart failure.

Official Title
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Dynamic Thoracic Impedance as a Marker for Heart Failure Decompensation: A Pilot Trial of the Dynamic Thoracic Impedance Bed Rest Test

Conditions
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Heart Failure; With Decompensation

Intervention / Treatment
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* Device: Medtronic ICDs, CRT-Ds, and CRT-Ps


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with systolic dysfunction Able to provide informed consent Have a Medtronic manufactured device with Thoracic Impendence Monitoring capabilities Exclusion Criteria: Patients with severe congestive heart failure who are intubated Patients who are oxygen dependent on continuous positive or bilevel positive ventilation Inability to tolerate postural variations due to congestive heart failure or other medical or surgical condition.Unable to complete proposed testing Subjects who cannot giveWill not give written, informed consent on their own behalf

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Heart Failure<br>Subjects have implanted Medtronic device and a primary diagnosis of left ventricular systolic dysfunction | Device: Medtronic ICDs, CRT-Ds, and CRT-Ps<br>* Any Medtronic implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy (CRT) device. Device must have capacity to measure thoracic impedance as described in protocol. This includes the majority of FDA-approved Medtronic devices currently in use.<br>* Other names: Consulta(R) CRT-P (Model C4TR01);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from sitting to supine to standing in thoracic impedance | thoracic impedance will be measured at each position at baseline visit then again at the follow-up visits through 30 days | Baseline, 30 Days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of change in thoracic impedance |  | Baseline, 30 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Thoracic Impedance, Diagnostic Marker, Bed Rest Test, Transthoracic Impedance, Heart Failure, HF