Sensor Optimization of Cardiac Resynchronization Therapy Response

Study Overview
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Brief Summary
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The Sensor Optimization of Cardiac Resynchronization Therapy (CRT) Response (SOCR) Study is a multicenter, prospective, non-randomized acute feasibility study that is being conducted to determine if subcutaneous heart sounds and/or intracardiac impedance can acutely identify the optimal atrioventricular (AV) pacing intervals and optimal left ventricular (LV) electrodes in patients indicated for cardiac resynchronization therapy.

Official Title
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Sensor Optimization of CRT Response

Conditions
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Heart Failure

Intervention / Treatment
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* Device: Cardiac Resynchronization Therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject must be undergoing implant of a new or replacement/upgrade Medtronic CRT-P or CRT-D device for approved indications. Subject is implanted or will be implanted with an right ventricular (RV) lead that supports bipolar pacing and sensing (e.g. a bipolar pace/sense lead or a true bipolar defibrillation leads) Subject (or subject's legally authorized representative) must be willing to give informed consent Subjects must be at least 18 years of age Exclusion Criteria: Subject has congenital heart disease Subject has a tachyarrhythmia (atrial and/or ventricular) at the time of enrollment and a cardioversion will not be attempted prior to the research procedure Subject has unstable coronary artery disease Subject cannot undergo transvenous catheterization Subject has a mechanical tricuspid or aortic valve prosthesis or history of significant structural tricuspid or aortic valvular disease Subject requires dual chamber cardiac pacing or single chamber (ventricular) pacing at rest for rate control Subject has a recent echocardiogram (within prior 6 months) which revealed the presence of an LV thrombus Subject is pregnant Subject is enrolled in a concurrent study that may confound the results of this study without documented pre-approval from Medtronic study manager

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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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cardiac Resynchronization Therapy<br>Patients implanted with a cardiac resynchronization therapy device | Device: Cardiac Resynchronization Therapy<br>* All study patients were evaluated for the optimal atrial-ventricular (AV) programmed interval using various methods.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AV Interval Determination Using Impedance | Current practices use the measurement LV dP/dt max to determine how the AV interval should be programmed in a CRT device. Intracardiac impedance is another method that could be used to determine the optimal AV interval. This outcome measure is the number of patients where the optimal AV interval setting as determined by intracardiac impedance agrees within one AV interval setting (30 milliseconds) of the optimal setting determined by LV dP/dt max. | During implant | 
| AV Interval Determination Using Heart Sounds | Current practices use the measurement LV dP/dt max to determine how the AV interval should be programmed in a CRT device. A heart sounds measure, called S1 Amplitude Transition, is another method that could be used to determine the optimal AV interval. This outcome measure is the number of patients where the optimal AV interval setting as determined by heart sounds agrees within one AV interval setting (30 milliseconds) of the optimal setting determined by LV dP/dt max | During implant | 
| Optimal Electrode Configuration Determination Using Impedance | Current practices use the measurement LV dP/dt max to determine how the optimal electrode configuration for a CRT device. Intracardiac impedance is another method that could be used to determine the optimal electrode configuration. This outcome measure is the number of patients where the optimal electrode configuration setting as determined by intracardiac impedance agrees with the optimal setting determined by LV dP/dt max | During implant | 
| Optimal Electrode Configuration Determination Using Heart Sounds | Current practices use the measurement LV dP/dt max to determine how the optimal electrode configuration for a CRT device. Heart sounds, as measured by S1 Amplitude, is another method that could be used to determine the optimal electrode configuration. This outcome measure is the number of patients where the optimal electrode configuration setting as determined by heart sounds agrees with the optimal setting determined by LV dP/dt max | During implant |