Micra Transcatheter Pacing Study
|ClinicalTrials.gov Identifier: NCT02004873|
Recruitment Status : Completed
First Posted : December 9, 2013
Results First Posted : January 5, 2017
Last Update Posted : January 17, 2018
|Condition or disease||Intervention/treatment||Phase|
|Class I or II Indication for Implantation of a Single Chamber Ventricular Pacemaker According to ACC/AHA/HRS 2001 Guidelines and Any National Guidelines||Device: Micra Pacemaker Implant||Not Applicable|
The study is being conducted in 56 sites located around the world, including 30 sites in the United States (U.S.).
Up to 780 subjects were planned to be enrolled (i.e. consented) to allow up to 720 subjects to be implanted enabling at least 600 subjects to be followed for at least 12-months post-implant.
There are two primary objectives in this study (one safety and one efficacy). The primary safety objective of the study is to evaluate major complications related to the Micra system or procedure. The primary safety endpoint was pre-specified to be evaluated at 6-months (183 days) post-implant. The primary efficacy objective, Micra pacing capture thresholds, was also pre-specified to be evaluated six months post-implant. This study also has a separate long term safety objective that will provide additional long-term safety data following potential regulatory submissions.
All subjects will be followed until official study closure (official study closure is defined as when Medtronic and/or FDA requirements have been satisfied per the Clinical Investigational Plan and/or by a decision by Medtronic or regulatory authority).
Additionally, the Micra Accelerometer Sensor Sub-Study (MASS) is being conducted at 4 centers already active in the Micra study in Austria, Spain, Hungary and France. Forty (40) subjects were enrolled in the Sub-Study, and enrollment in the Sub-Study was complete as of March 31, 2016. The purpose of the Sub-Study is to test feasibility for future enhancements in the Micra device functionalities.
An algorithm was designed to sense the atrial contraction using the Micra accelerometer.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||744 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Micra Transcatheter Pacing Study|
|Actual Study Start Date :||November 2013|
|Actual Primary Completion Date :||May 2015|
|Actual Study Completion Date :||May 2017|
|Experimental: Micra Pacemaker Implant||
Device: Micra Pacemaker Implant
- Major Complications [ Time Frame: Implant to 6 Months Post Implant ]Micra system and/or procedure related major complication free rate at 6-months post-implant.
- Pacing Capture Threshold [ Time Frame: 6 Months Post Implant ]Subjects that have an adequate pacing capture threshold (PCT) at the 6-month post-implant visit, which is defined as PCT <=2 volts at 0.24 ms pulse width and the increase in PCT from implant to 6 months <=1.5 volts. The pacing capture threshold is the minimal electrical stimulus required to produce consistent cardiac depolarization. It is the minimum amount of energy that is required for a pacemaker to pace the heart.
- Ventricular Capture Management Threshold [ Time Frame: 6 Months Post Implant ]Subjects that have a ventricular capture management threshold (VCMT) that is within 0.5 Volts of the manual (auto decrement) PCT (at 0.24 ms pulse width) at the 6-month post-implant visit. The VCMT is an automatically measured pacing capture threshold that is measured by the Micra device's pacing algorithm. In contrast, the manual (auto decrement) pacing capture threshold is measured by the clinician during a study visit.
- Rate Response Operation of Micra [ Time Frame: 3 Months and 6 Months Post Implant (combined analysis) ]Assessment of whether the Micra sensor-indicated rate derived from the input of the accelerometer during the Minnesota Pacemaker Response Exercise Protocol (M-PREP) treadmill test conducted at the 3-month and 6-month follow-up visits was proportional to the workload. The sensor-indicated rate (in min^-1) and workload (in METS) were normalized for each subject relative to their minimum and maximum possible values so the normalized values have a minimum possible value of zero and a maximum possible value of 1. These normalized values were used in a random effect linear regression model to assess the relationship between the sensor-indicated rate and workload via estimation of the Kay-Wilkoff slope parameter. The tests at 3-month and 6-month visits were combined in one analysis.
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 ClinicalTrials.gov identifier (NCT number): NCT02004873
|Study Chair:||Dwight Reynolds||University of Oklahoma|
|Study Chair:||Philippe Ritter||Hôpital Haut-Lévêque|