ProMRI Study of the Entovis Pacemaker System (Phase B)

Study Overview
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Brief Summary
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The objective of the ProMRI Study (Phase B) is to demonstrate the clinical safety of the ProMRI Pacemaker System when used under specific MRI conditions without scan exclusion zone.

Conditions
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Magnetic Resonance Imaging (MRI); Cardiac Pacing

Intervention / Treatment
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* Device: Patients with a ProMRI Pacemaker System
* Other: Magnetic Resonance Imaging (MRI) scan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The following initial inclusion criteria must be met for a subject to be enrolled and considered for the MRI-procedure: Age greater than 18 years Able and willing to complete MRI testing Able to provide written informed consent Available for follow-up visit at the study site Implanted with a pacemaker system consisting only of an Entovis pacemaker (DR-T, SR-T) and one or two Setrox S 53 or Setrox S 60 pacemaker lead(s). (No leads other than Setrox S (53 or 60 cm) leads may be implanted. This includes lead extensions or abandoned leads in the subject.) Pacemaker implanted pectorally All pacemaker system components implanted, repositioned, or exchanged at least 5 weeks prior to enrollment Underling rhythm identifiable during sensing test All pacing thresholds are measureable and are less than or equal to 2.0 V @0.4 ms Absence of phrenic nerve stimulation at 4.8V @ 1.0 ms Pacing impedance is between 200 and 1500 ohm Able and willing to use the Cardio Messenger At the pre-MRI procedure, the following procedure-related criteria must be met for the subject to undergo the MRI scan: Absence of phrenic nerve stimulation at 4.8V @ 1.0 ms •|pacing threshold at Pre-MRI follow-up - pacing threshold at baseline| ≤ 0.5 V All pacing thresholds are measureable and are ≤ 2.0 V @ 0.4 ms The pacemaker system has been implanted for at least 6 weeks. Subject did not have a pacemaker or lead explant, exchange or reposition in the previous 6 weeks. All lead impedances are between 200 and 1500 ohm. Battery status is at least 30% of capacity Exclusion Criteria: Enrolled in any other clinical study For pacemaker systems that include an atrial lead, subjects with either Persistent atrial arrhythmia (lasting longer than 7 days or requiring cardioversion) Permanent atrial arrhythmia Life expectancy of less than three months Pregnancy Cardiac surgery expected in the next three months Implanted with other medical devices that may interact with MRI, such as: abandoned pacemaker/ICD leads lead extensions mechanical valves other active medical devices non-MRI compatible devices other metallic artifacts/components in body that may interact with MRI

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 |
| --- | --- |
| Pacemaker Therapy<br>Patients with a ProMRI Pacemaker System | Device: Patients with a ProMRI Pacemaker System<br>* Bradycardia Slow Heart Beat<br>Other: Magnetic Resonance Imaging (MRI) scan<br>* MRI scan of heart/chest or thoracic spine.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| MRI and Pacing System Related Serious Adverse Device Effect (SADE) Free Rate |  | 1 Month Post-MRI | 
| Percentage of Participants Free of Atrial Pacing Threshold Rise | Evaluate the percentage of atrial pacing leads with a pacing threshold increaess between the Pre-MRI and one-month post-MRI follow-up. | Between Pre-MRI and 1 Month Post-MRI | 
| Percentage of Participants Free of Ventricular Pacing Threshold Rise | Evaluate the percentage of ventricular pacing leads with a pacing threshold increase between the Pre-MRI and one-month post-MRI follow-up. | Between Pre-MRI and 1 Month Post-MRI | 
| Percentage of Participants Free of P-wave Sensing Attenuation | Evaluate the percentage of subjects who experience P-wave attenuation between the pre-MRI and one-month post-MRI follow-up. | Between Pre-MRI and 1 Month Post-MRI | 
| Percentage of Participants Free of R-wave Sensing Attenuation | Evaluate the percentage of subjects who experience R-wave attenuation between the pre-MRI and one-month post-MRI follow-up. | Between Pre-MRI and 1 Month Post-MRI |