Adverse Effect of MRI on an Implanted Pacemaker, Adverse Effect of MRI on an Implanted Pacemaker Lead
Conditions
Keywords
bradycardia, MRI scans
Brief summary
The MRI Study is a prospective, multi-center, clinical study designed to evaluate the safety and efficacy of the Accent MRI™ System in a patient population indicated for implant of a pacemaker within and outside of the MRI environment.
Detailed description
The MRI Study is a prospective, multi-center, clinical study designed to evaluate the safety and efficacy of the Accent MRI System in a patient population indicated for implant of a pacemaker within and outside of the MRI environment. The study consisted of two phases, a Lead Safety Phase which evaluated the safety of the Tendril MRI lead, and an MRI Phase which evaluated the safety and efficacy of the Accent MRI pacemaker system in an MRI environment. The safety and efficacy of the Accent MRI pacemaker and Tendril MRI lead will be evaluated as described below: Lead Safety Safety of the Tendril MRI™ lead will be evaluated in terms of freedom from right atrial (RA) and right ventricle (RV) lead-related complications at implant to 2 months (acute timeframe), and at the 2 through the 12 month visit (chronic timeframe). MRI Safety The safety of the Accent MRI™ system will be evaluated in terms of freedom from MRI scan related complications in the month following the MRI scan. Lead Efficacy Efficacy of the Tendril MRI™ lead will be evaluated in terms of the change in atrial and ventricular capture and sensing thresholds before and after the MRI scan. MRI Efficacy Efficacy of the Tendril MR lead will be evaluated in terms of the change in bipolar atrial and ventricular capture and sensing thresholds before and after the MRI scan. Secondary Endpoints Safety Safety of the Accent MRI™ system will be evaluated in terms of freedom from system-related complications through the 12 month visit. Efficacy Efficacy of the Tendril MRI™ lead will be evaluated in terms of the atrial and ventricular capture thresholds at the MRI Visit.
Interventions
DEVICEAccent MRI system (lead safety)
Patients implanted with an Accent MRI system
DEVICEAccent MRI system (with MRI scan)
Patients implanted with an Accent MRI system will receive an MRI scan
Sponsors
Abbott Medical Devices
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
Eligible patients will meet all of the following: 1. Have an approved indication per American College of Cardiology (ACC)/American Heart Association (AHA)/Heart Rhythm Society (HRS) guidelines for implantation of a pacemaker 2. Will receive a new pacemaker and lead 3. Be willing to undergo an elective MRI scan without sedation 4. Be able to provide informed consent for study participation (legal guardian is NOT acceptable) 5. Be willing and able to comply with the prescribed follow-up tests and schedule of evaluations 6. Is not contraindicated for an MRI scan (per the pre-MRI safety screening form)
Exclusion criteria
Patients will be excluded if they meet any of the following: 1. Are medically indicated for an MRI scan at the time of enrollment 2. Have an existing pacemaker or implantable cardioverter defibrillator (ICD). A new pacemaker and lead is required for enrollment 3. Have an existing active/inactive implanted medical device, e.g., neurostimulator, infusion pump, etc. 4. Have a non-MRI compatible device or material implanted (e.g., intracranial aneurysm clip, non-MRI compatible devices or material, metals or alloys, etc.) 5. Have a lead extender or adaptor 6. Be unable to fit in MRI bore; will come into contact with the magnet façade inside the MRI bore. 7. Have a prosthetic tricuspid heart valve 8. Are currently participating in a clinical investigation that includes an active treatment arm 9. Are allergic to dexamethasone sodium phosphate (DSP) 10. Are pregnant or planning to become pregnant during the duration of the study 11. Have a life expectancy of less than 12 months due to any condition 12. Patients with
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Ventricular Sense Amplitude | MRI Scan visit to 1 month after the MRI Scan visit | Percentage of patients with an reduction in RV sense amplitude \<=50% and sense amplitude \>=5 mV. |
| Freedom From MRI Scan-related Complications | MRI Scan visit through 1 month after MRI scan visit | Percentage of patients who do not have MRI-related complications from the MRI scan visit to the 1 month post MRI scan visit |
| Change in Ventricular Capture Threshold Pre to Post MRI Scan | MRI Scan visit to 1 month after MRI scan visit | Percentage of patients with an increase in RV capture thresholds of \<=0.5V, at a pulse width of 0.5 ms. |
| Change in Atrial Sense Amplitude | MRI Scan visit to 1 month after MRI scan visit | Percentage of patients with a reduction in RA sense amplitude \<=50 % and sense amplitude \>=1.5 mV. |
| Change in Atrial Capture Threshold From Pre to Post MRI Scan | MRI Scan visit to 1 month after MRI scan visit | Percentage of patients with an increase in RA capture thresholds of \<= 0.5 V, at a pulse width of 0.5 ms . |
| Freedom From Right Atrial (RA) Lead-related Complications in the Acute Period | Implant through 2 months | Percentage of patients who do not have RA lead-related complications from implant through the 2 month study visit |
| Freedom From Right Ventricular (RV) Lead-related Complications in the Acute Time Period | Implant through 2 months | Percentage of patients who do not have RV lead-related complications from implant through the 2 month study visit |
| Freedom From RA Related Complications in the Chronic Period | 2 months through 12 months | Percentage of patients who do not have RA lead-related complications from the 2 month through the 12 month study visit |
| Freedom From Right Ventricular Lead Related Complications in the Chronic Period | 2 months through 12 months | Percentage of patients who do not have RV lead-related complications from the 2 month through the 12 month study visit |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Atrial Capture Threshold at the MRI Visit | MRI Scan visit (approx 3 months post implant) | Percentage of patients with RA capture threshold ≤2.0 volts (V) at the MRI visit |
| Ventricular Capture Threshold at the MRI Visit | MRI Scan visit (approx 3 months post implant) | Percentage of patients with RV capture threshold ≤2.0 V at the MRI visit |
| Freedom From System-related Complications | Implant through 12 months | Percentage of patients who do not have system-related complications from implant through the 12 month study visit |
Countries
Australia, Belgium, Finland, Netherlands, United States
Participant flow
Recruitment details
Lead safety phase: enrollment began on 03-30-2012 and ended on 06-18-2013; enrollment occured at 68 sites and 920 patients were enrolled. MRI Phase: study was approved by FDA on 03-26-2014. 255 patients were enrolled into the MRI Phase. 181 scans were completed by the 10-30-2014 cut-off date: 151 in the US, and 30 supplemental scans in Australia. The patients enrolled in the US came from the lead safety phase, the supplemental scans in Australia did not participate in lead safety phase.
Pre-assignment details
The MRI phase was originally designed as a randomized study, with MRI and control groups, but due to challenges encountered with patient recruitment, it was later changed to a non-randomized study.
Participants by arm
| Arm | Count |
|---|---|
| Lead Safety Phase Evaluate the safety and efficacy of the St. Jude Medical Accent MRI system, which includes the Tendril MRI™ lead and Accent MRI™ pacemaker. | 920 |
| MRI Phase A subset of patients enrolled in the Lead safety phase (225 subjects from lead safety phase) underwent an elective MRI scan to evaluate the safety and efficacy of Accent MRI system within the MRI environment. | 255 |
| Total | 1,175 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Lead Safety | Death | 132 | 0 |
| Lead Safety | Device replaced with CRT-D | 1 | 0 |
| Lead Safety | Lost to Follow-up | 13 | 0 |
| Lead Safety | Patient no longer followed by study PI | 1 | 0 |
| Lead Safety | Patient noncompliance | 1 | 0 |
| Lead Safety | Patient on Palliative Care | 1 | 0 |
| Lead Safety | Physician Decision | 14 | 0 |
| Lead Safety | Sponsor request | 1 | 0 |
| Lead Safety | System deactivated | 1 | 0 |
| Lead Safety | System Explanted without Replacement | 24 | 0 |
| Lead Safety | Too far from study site | 1 | 0 |
| Lead Safety | Unsuccessful implant | 2 | 0 |
| Lead Safety | Withdrawal by Subject | 81 | 0 |
| MRI Safety | Has not yet completed MRI scan | 0 | 56 |
| MRI Safety | MRI scan not performed at MRI visit | 0 | 3 |
| MRI Safety | Non-MRI Compatible Device or Material | 0 | 5 |
| MRI Safety | Withdrawal by Subject | 0 | 10 |
Baseline characteristics
| Characteristic | Lead Safety Phase | Total | MRI Phase |
|---|---|---|---|
| Age, Continuous Age - Lead Safety Phase | 73.5 years STANDARD_DEVIATION 10.8 | 73.5 years STANDARD_DEVIATION 10.8 | — |
| Age, Continuous Age - MRI Safety Phase | — | 70.2 years STANDARD_DEVIATION 11.6 | 70.2 years STANDARD_DEVIATION 11.6 |
| Cardiovascular History Lead Safety Phase Coronary Artery Disease | 338 Participants | 338 Participants | — |
| Cardiovascular History Lead Safety Phase Myocardial Infarction | 119 Participants | 119 Participants | — |
| Cardiovascular History Lead Safety Phase None | 390 Participants | 390 Participants | — |
| Cardiovascular History Lead Safety Phase Unstable Angina | 73 Participants | 73 Participants | — |
| Cardiovascular History MRI Safety Phase Coronary Artery Disease | — | 35 Participants | 35 Participants |
| Cardiovascular History MRI Safety Phase Myocardial Infarction | — | 5 Participants | 5 Participants |
| Cardiovascular History MRI Safety Phase None | — | 209 Participants | 209 Participants |
| Cardiovascular History MRI Safety Phase Unstable Angina | — | 6 Participants | 6 Participants |
| Ethnicity (NIH/OMB) Lead Safety Phase Hispanic or Latino | 14 Participants | 14 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Lead Safety Phase Not Hispanic or Latino | 904 Participants | 904 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Lead Safety Phase Unknown or Not Reported | 2 Participants | 2 Participants | 0 Participants |
| Ethnicity (NIH/OMB) MRI Safety Phase Hispanic or Latino | 0 Participants | 4 Participants | 4 Participants |
| Ethnicity (NIH/OMB) MRI Safety Phase Not Hispanic or Latino | 0 Participants | 251 Participants | 251 Participants |
| Ethnicity (NIH/OMB) MRI Safety Phase Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Non-Ventricular Arrhythmia History Atrial Flutter - lead safety | 123 participants | 123 participants | 0 participants |
| Non-Ventricular Arrhythmia History Atrial Flutter - MRI safety | 0 participants | 39 participants | 39 participants |
| Non-Ventricular Arrhythmia History Atrial Tachycardia - lead safety | 41 participants | 41 participants | 0 participants |
| Non-Ventricular Arrhythmia History Atrial Tachycardia - MRI safety | 0 participants | 16 participants | 16 participants |
| Non-Ventricular Arrhythmia History None - lead safety | 370 participants | 370 participants | 0 participants |
| Non-Ventricular Arrhythmia History None - MRI safety | 0 participants | 111 participants | 111 participants |
| Non-Ventricular Arrhythmia History Paroxysmal AF - lead safety | 316 participants | 316 participants | 0 participants |
| Non-Ventricular Arrhythmia History Paroxysmal AF - MRI safety | 0 participants | 79 participants | 79 participants |
| Non-Ventricular Arrhythmia History Permanent AF - lead safety | 63 participants | 63 participants | 0 participants |
| Non-Ventricular Arrhythmia History Permanent AF - MRI safety | 0 participants | 16 participants | 16 participants |
| Non-Ventricular Arrhythmia History Persistent AF - lead safety | 100 participants | 100 participants | 0 participants |
| Non-Ventricular Arrhythmia History Persistent AF - MRI safety | 0 participants | 23 participants | 23 participants |
| Non-Ventricular Arrhythmia History Supra Ventricular - lead safety | 55 participants | 55 participants | 0 participants |
| Non-Ventricular Arrhythmia History Supra Ventricular - MRI safety | 0 participants | 10 participants | 10 participants |
| Primary Indication for Pacemaker Implant Lead Safety Phase AV block | 246 Participants | 246 Participants | — |
| Primary Indication for Pacemaker Implant Lead Safety Phase Other | 19 Participants | 19 Participants | — |
| Primary Indication for Pacemaker Implant Lead Safety Phase Pacemaker Generator Change | 2 Participants | 2 Participants | — |
| Primary Indication for Pacemaker Implant Lead Safety Phase Prevention/Termination Of Tachyarrhythmias By Paci | 13 Participants | 13 Participants | — |
| Primary Indication for Pacemaker Implant Lead Safety Phase Sinus Node Dysfunction | 581 Participants | 581 Participants | — |
| Primary Indication for Pacemaker Implant Lead Safety Phase Syncope | 59 Participants | 59 Participants | — |
| Primary Indication for Pacemaker Implant MRI Safety Phase AV block | — | 65 Participants | 65 Participants |
| Primary Indication for Pacemaker Implant MRI Safety Phase Other | — | 7 Participants | 7 Participants |
| Primary Indication for Pacemaker Implant MRI Safety Phase Pacemaker Generator Change | — | 1 Participants | 1 Participants |
| Primary Indication for Pacemaker Implant MRI Safety Phase Prevention/Termination Of Tachyarrhythmias By Paci | — | 5 Participants | 5 Participants |
| Primary Indication for Pacemaker Implant MRI Safety Phase Sinus Node Dysfunction | — | 159 Participants | 159 Participants |
| Primary Indication for Pacemaker Implant MRI Safety Phase Syncope | — | 18 Participants | 18 Participants |
| Prior Cardiac Interventions Lead Safety Phase Ablation | 100 Participants | 100 Participants | — |
| Prior Cardiac Interventions Lead Safety Phase Coronary Artery Bypass Graft | 130 Participants | 130 Participants | — |
| Prior Cardiac Interventions Lead Safety Phase None | 538 Participants | 538 Participants | — |
| Prior Cardiac Interventions Lead Safety Phase PTCA/Stents/Atherectomy | 152 Participants | 152 Participants | — |
| Prior Cardiac Interventions MRI Safety Phase Ablation | — | 38 Participants | 38 Participants |
| Prior Cardiac Interventions MRI Safety Phase Coronary Artery Bypass Graft | — | 2 Participants | 2 Participants |
| Prior Cardiac Interventions MRI Safety Phase None | — | 207 Participants | 207 Participants |
| Prior Cardiac Interventions MRI Safety Phase PTCA/Stents/Atherectomy | — | 8 Participants | 8 Participants |
| Race (NIH/OMB) Lead Safety Phase American Indian or Alaska Native | 3 Participants | 3 Participants | 0 Participants |
| Race (NIH/OMB) Lead Safety Phase Asian | 12 Participants | 12 Participants | 0 Participants |
| Race (NIH/OMB) Lead Safety Phase Black or African American | 51 Participants | 51 Participants | 0 Participants |
| Race (NIH/OMB) Lead Safety Phase More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Lead Safety Phase Native Hawaiian or Other Pacific Islander | 2 Participants | 2 Participants | 0 Participants |
| Race (NIH/OMB) Lead Safety Phase Unknown or Not Reported | 10 Participants | 10 Participants | 0 Participants |
| Race (NIH/OMB) Lead Safety Phase White | 842 Participants | 842 Participants | 0 Participants |
| Race (NIH/OMB) MRI Safety Phase American Indian or Alaska Native | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) MRI Safety Phase Asian | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) MRI Safety Phase Black or African American | 0 Participants | 20 Participants | 20 Participants |
| Race (NIH/OMB) MRI Safety Phase More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) MRI Safety Phase Native Hawaiian or Other Pacific Islander | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) MRI Safety Phase Unknown or Not Reported | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) MRI Safety Phase White | 0 Participants | 229 Participants | 229 Participants |
| Region of Enrollment Australia | — | 30 participants | 30 participants |
| Region of Enrollment United States | 920 participants | 920 participants | 225 participants |
| Sex: Female, Male Sex - Lead Safety Phase Female | 421 Participants | 421 Participants | — |
| Sex: Female, Male Sex - Lead Safety Phase Male | 499 Participants | 499 Participants | — |
| Sex: Female, Male Sex - MRI Safety Phase Female | — | 114 Participants | 114 Participants |
| Sex: Female, Male Sex - MRI Safety Phase Male | — | 141 Participants | 141 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 132 / 920 | 0 / 255 |
| other Total, other adverse events | 60 / 920 | 1 / 255 |
| serious Total, serious adverse events | 70 / 920 | 0 / 255 |
Outcome results
Primary
Change in Atrial Capture Threshold From Pre to Post MRI Scan
Percentage of patients with an increase in RA capture thresholds of \<= 0.5 V, at a pulse width of 0.5 ms .
Time frame: MRI Scan visit to 1 month after MRI scan visit
Population: 37 of the 181 subjects that underwent a MRI scan did not have RA capture threshold data at 1-month post scan; no RA lead: 10; RA lead off: 3; atrial fibrillation (AF/AFl) during measurement: 10; 1-month visit not completed: 14.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Change in Atrial Capture Threshold From Pre to Post MRI Scan | 100 percentage of subjects |
Primary
Change in Atrial Sense Amplitude
Percentage of patients with a reduction in RA sense amplitude \<=50 % and sense amplitude \>=1.5 mV.
Time frame: MRI Scan visit to 1 month after MRI scan visit
Population: 60 of the 181 subjects that underwent an MRI scan did not have RA sense amplitude data: no RA lead: 10; RA lead off: 3; AF/AFl/ heart rate\< 30 bpm/ no P-wave during measurement: 11; P-wave \< 1.5 mV: 23; 1-month visit not yet completed: 12; AF/AFl during 1-month measurement: 1
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Change in Atrial Sense Amplitude | 92.56 percentage of subjects |
Primary
Change in Ventricular Capture Threshold Pre to Post MRI Scan
Percentage of patients with an increase in RV capture thresholds of \<=0.5V, at a pulse width of 0.5 ms.
Time frame: MRI Scan visit to 1 month after MRI scan visit
Population: 167 of the 181 subjects with an MRI scan had completed the 1-month post MRI visit. Data from 167 subjects was available for this analysis; 13 subjects had not completed 1 month follow-up, 1 subject had RV capture threshold missing or not done.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Change in Ventricular Capture Threshold Pre to Post MRI Scan | 100 percentage of subjects |
Primary
Change in Ventricular Sense Amplitude
Percentage of patients with an reduction in RV sense amplitude \<=50% and sense amplitude \>=5 mV.
Time frame: MRI Scan visit to 1 month after the MRI Scan visit
Population: 47 of 181 subjects that underwent an MRI scan did not have RV sense amplitude: no R-wave/HR \< 30 beats per minute (BPM): 18; R-wave amplitude \< 5 mV: 18; one-month visit not completed: 11. 134 subjects were available for evaluation of endpoint.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Change in Ventricular Sense Amplitude | 97.76 percentage of subjects |
Primary
Freedom From MRI Scan-related Complications
Percentage of patients who do not have MRI-related complications from the MRI scan visit to the 1 month post MRI scan visit
Time frame: MRI Scan visit through 1 month after MRI scan visit
Population: 151 of the 255 patients enrolled received an MRI scan. An additional 30 scans were performed using an identical scan protocol implemented in this study, for a total of 181 patients who underwent an MRI scan.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Freedom From MRI Scan-related Complications | 100 percentage of subjects |
Primary
Freedom From RA Related Complications in the Chronic Period
Percentage of patients who do not have RA lead-related complications from the 2 month through the 12 month study visit
Time frame: 2 months through 12 months
Population: Data from 114 subjects were unavailable for this endpoint analysis due to the following reasons: no RA lead: 99; death: 8; unsuccessful implant: 2; withdrawal:5.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Freedom From RA Related Complications in the Chronic Period | 98.82 percentage of subjects |
Primary
Freedom From Right Atrial (RA) Lead-related Complications in the Acute Period
Percentage of patients who do not have RA lead-related complications from implant through the 2 month study visit
Time frame: Implant through 2 months
Population: 99 of the 920 enrolled subjects had no RA lead and hence did not contribute any data towards this endpoint.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Freedom From Right Atrial (RA) Lead-related Complications in the Acute Period | 97.2 percentage of subjects |
Primary
Freedom From Right Ventricular Lead Related Complications in the Chronic Period
Percentage of patients who do not have RV lead-related complications from the 2 month through the 12 month study visit
Time frame: 2 months through 12 months
Population: Data from 18 subjects were unavailable for this endpoint analysis due to the following reasons: no RV lead: 1; death: 9; unsuccessful implant: 2; withdrawal: 6.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Freedom From Right Ventricular Lead Related Complications in the Chronic Period | 100 percentage of subjects |
Primary
Freedom From Right Ventricular (RV) Lead-related Complications in the Acute Time Period
Percentage of patients who do not have RV lead-related complications from implant through the 2 month study visit
Time frame: Implant through 2 months
Population: one of 920 enrolled subjects did not have an RV lead implanted.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Freedom From Right Ventricular (RV) Lead-related Complications in the Acute Time Period | 98.45 percentage of subjects |
Secondary
Atrial Capture Threshold at the MRI Visit
Percentage of patients with RA capture threshold ≤2.0 volts (V) at the MRI visit
Time frame: MRI Scan visit (approx 3 months post implant)
Population: 23 of the 181 subjects that underwent an MRI scan did not have RA capture threshold for the MRI scan visit: no RA lead: 10; RA lead off: 3; AF/AFl during measurement: 10.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Atrial Capture Threshold at the MRI Visit | 100.00 percentage of subjects |
Secondary
Freedom From System-related Complications
Percentage of patients who do not have system-related complications from implant through the 12 month study visit
Time frame: Implant through 12 months
Population: All subjects enrolled in the lead-safety arm.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Freedom From System-related Complications | 94.64 percentage of subjects |
Secondary
Ventricular Capture Threshold at the MRI Visit
Percentage of patients with RV capture threshold ≤2.0 V at the MRI visit
Time frame: MRI Scan visit (approx 3 months post implant)
Population: All subjects that underwent a MRI scan had ventricular capture threshold data available.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Lead Safety Phase | Ventricular Capture Threshold at the MRI Visit | 100.00 percentage of subjects |