Micra Atrial Tracking Using a Ventricular Accelerometer Study

Study Overview
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Brief Summary
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The purpose of this study is to characterize performance of the MARVEL algorithm downloaded into the MicraTM TPS to provide atrial synchronous ventricular pacing in subjects with AV block. A sub-study will be conducted within the Marvel study, the purpose of this study is to characterize the MARVEL algorithm in patients who were enrolled in the MARVEL study, and to collect and compare the accelerometer signals and AV synchrony at a second point in time.

Official Title
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Micra Atrial Tracking Using a Ventricular Accelerometer Study

Conditions
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Atrioventricular Conduction Block

Intervention / Treatment
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* Device: MARVEL algorithm


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject has been implanted with, or is expected to be implanted with a MicraTM TPS (Model MC1VR01), with remaining device longevity of 6 years or more. Subject is ≥ 18 years old and as per required local law. Subject has atrioventricular (AV) block. Subject (and/or witness, as applicable per local regulations) provides signed and dated authorization and/or consent per institution and local requirements. Subject is willing and able to comply with the protocol. Exclusion Criteria: Subject is in atrial arrhythmia at the time of enrollment. Subject is currently enrolled or planning to participate in a potentially confounding drug or device trial during the study. Co-enrollment in concurrent trials is only allowed when documented pre-approval is obtained from the Medtronic study manager. Subject is pregnant (if required by local law, women of child-bearing potential must undergo a pregnancy test within seven days prior to MARVEL study procedures). Subject meets any exclusion criteria required by local law (age or other). Additional criteria for the MARVEL Evolve Sub-study: Inclusion criteria: • Subjects in the MARVEL Sub-Study have previously been enrolled in the MARVEL main study

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: Device Feasibility
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Enrolled<br>Subjects enrolled in the MARVEL study. Enrolled subjects will have the MARVEL algorithm downloaded into their implanted market released Micra device. | Device: MARVEL algorithm<br>* Software download into implanted Micra device<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Atrioventricular synchrony | On an individual heartbeat basis, this is defined as a right ventricular paced or sensed R-wave associated with an ECG confirmed P-wave. | Initial 24 hour period after patient enrollment | 
| MARVEL Evolve Substudy | Characterize the rate of atrioventricular synchrony provided by the MARVEL algorithm and compare the accelerometer signal amplitudes and the AV synchrony provided by the MARVEL algorithm with the data collected during the initial MARVEL procedure. | Initial 24 hour period after patient enrollment |