MRI safe pacemaker: waarom niet?

MRI safe pacemaker/ICD contra!Dr. A.F.M. KuijperSpaarneziekenhuis, HoofddorpAmersfoort 28 september 2012

2010 ACCF/ACR/AHA/NASCI/SCMR Expert Consensus Permanent Cardiac Pacemakers and ICD (1)

damage or movement of the deviceinhibition of pacing outputactivation of tachyarrhythmia therapy of the devicecardiac stimulationheating of the electrode tips

-> changes in pacing/defibrillation thresholds, pacemaker ICD dysfunction or damage (including battery depletion), arrhythmia, or death. 2010 ACCF/ACR/AHA/NASCI/SCMR Expert Consensus Permanent Cardiac Pacemakers and ICD(2)

Few small clinical trials under which MR examination with these devices could be conducted safely.

Pacemaker-dependent patients were excluded from these studies, no episodes of pacing above the upper rate limit or arrhythmias were noted, though 1 patient had a change in device programming.

ICDs and pacemakers manufactured after the year 2000 are more resistant to the electrical and magnetic fields associated with MR examination at 1.5-T.

no deaths have been reported under conditions in which patients were deliberately scanned and monitored during MRI , although changes in pacing threshold, programming changes, need for device reprogramming, and possibly battery depletion have been reported. 2010 ACCF/ACR/AHA/NASCI/SCMR Expert Consensus Permanent Cardiac Pacemakers and ICD(3)

2010 pacemakers in the USA MR unsafe MRI examination of patients with pacemaker - is discouraged- only at highly experienced centers- strong clin. indication, benefits outweigh risk - ICD pts in highly experienced ICD/MRI center

2010 ACCF/ACR/AHA/NASCI/SCMR Expert Consensus Permanent Cardiac Pacemakers and ICD(4) Retained Transvenous Pacemaker and Defibrillator Leads

No studies in MRI with retained pacemaker or ICD leads (either functioning or fractured). Significant heating of the lead tips may occur. Discouraged.

MRI in EP center when no alternatives to MRI under compelling clinical circumstances. J Am Coll Cardiol 2009;54:54955

J Am Coll Cardiol 2009;54:549558

J Am Coll Cardiol 2009;54:549559MRI at 1.5-T in pts With ICD Naehle et al. J Am Coll Cardiol 2009;54: 5495518 Nonpacemaker-dependent ICD patientsSpecific Absorption Rate (SAR) was limited to 2 W/kg. ICDs reprogrammed to avoid competitive pacing and potential pro-arrhythmia: 1) the lower rate limit as low as reasonably achievable; and 2) arrhythmia detection on, therapy delivery off, (detection off programming consumes less battery current). ECG+ pulse oximetry. All ICDs were interrogated before and after the MRI examination and after 3 months, including measurement of pacing capture threshold, lead impedance, battery voltage, and serum troponin I.J Am Coll Cardiol 2009;54:5495510

J Am Coll Cardiol 2009;54:5495511MRI at 1.5-T in pts With ICD Naehle et al. J Am Coll Cardiol 2009;54: 54955All 18 examinations were completed safely. All ICDs interrogated and reprogrammed post-MRI. No changes of pacing capture threshold, lead impedance, and serum troponin I were observed.Battery voltage decreased significantly from pre- to post-MRI. (4 complete, 9 partial recovery, 3 no recov, 2 missing).Mean battery voltage decreased from pre-MRI 3.86 1.48 V, to post-MRI 3.83 1.48 V but was 3.90 1.52 V at FU.In 2 MRI examinations, oversensing of radiofrequency noise as ventricular fibrillation occurred. However, no attempt at therapy delivery was made.J Am Coll Cardiol 2009;54:5495512Editorial Roguin JACC 2009FDA : for some patients, risks of MRI under specific, characterized scanning and monitoring conditions may be acceptable given the diagnostic benefit. Risks of MR scanning should be discussed with the patient, with written informed consent. In ICD patients the MR study should be performed at centers with expertise in MRI and electrophysiology. The MR scan should be optimally planned in order to minimize time and energy. A physician who is knowledgeable in device therapy and programming should be present during the MR scan. Pre-MR reprogramming, careful patient monitoring during MR scanning, and thorough follow-up after MR scanning must be performed. Full resuscitation facilities should be available should any adverse event occur during MR scanning.

J Am Coll Cardiol 2009;54:5495513Am Heart J 2011;161:1096-105

Am Heart J 2011;161:1096-10514Safety, feasibility, and diagnostic value of cardiac MRI in patients with cardiac pacemakers and implantable cardioverters defibrillators at 1.5 T Am Heart J 2011;161:1096- Naehle et al

Am Heart J 2011;161:1096-10515Patients and MethodsPM/ICD systems > 3 months after implantstable physical parameters EOL> 6 monthspacing lead impedances 200-2000 shock lead impedance, 10-80 stable functional parameters (pacing capture threshold .5 mV). No abandoned leads or presence of other MR imagingincompatible devices.Am Heart J 2011;161:1096-10516Device en onderzoeksindicatie

Am Heart J 2011;161:1096-10517Resultaten procedure safety (1)No unexpected changes in heart rate or rhythm, indicating inhibition of ICD output, shock delivery, or sustained atrial or ventricular arrhythmias.No torque or heating sensation during MR imaging.No changes programmed parameters. No change of pacing thresholdNo change of pacing lead impedance to >2,000 or 80 or 3 MRIAnn Intern Med. 2011;155:415-424.30Acute resultatenPower on reset bij 3/438 (0.7%), 1 MRI stop, 2 uneventfull MRINo device revision, programming, or interventions at MRI examination were otherwise required. In pacemakers without magnet-mode programming capability, reed switch activation by MRI led to transient, asymptomatic asynchronous pacing at the pacemaker-specific magnet rate. No unexpected or rapid activation of pacing was observed during MRI.Ann Intern Med. 2011;155:415-424.31

Ann Intern Med. 2011;155:415-424.32Lead Sensing, Impedance, and Capture Thresholds at Immediate and Long-Term Follow-upNo immediate or long-term change in variables in any patient was large enough to require lead or system revision or device reprogramming.Overall, MRI was performed safely in all patients.When the device was located in the MRI field of view, image distortion, signal voids or bright areas, and poor fat suppression were noted.Selecting imaging planes perpendicular to the plane of the device generator, shortening the echo time, and using spin echo and fast spin echo sequences reduced the qualitative extent of artifact.Artifacts, were limited to thoracic examinations, and the great majority of examinations yielded clinically useful information.Ann Intern Med. 2011;155:415-424.34Thoracic MRI may pose more risk owing to greater power deposition over the region containing the device. The association between thoracic imaging and long-term right ventricular sensing in our study supports this hypothesis.Ann Intern Med. 2011;155:415-424.35MRI bij pacemaker afhankelijke pt (1)53 pacemaker-dependent patients without ICD underwent MRI without safety issues. It is vital, however, to emphasize the need for appropriate programming of the device to an asynchronous mode, monitoring by qualified personnel, and availability of external pacing backup for such patientsAnn Intern Med. 2011;155:415-424.36MRI bij pacemaker afhankelijke pt (2)If a power-on-reset event occurs, the device reverts to an inhibited pacing mode. Therefore, in pacemaker-dependent patients, the device may transiently cease pacing owing to EMI, and electrocardiographic monitoring and pulse oximetry are necessary so that the scan can be stopped if inhibition of pacing is noted.Ann Intern Med. 2011;155:415-424.37Conclusie 1Using a protocol based on device selection and programming, MRI can be performed safely in patients with certain pacemaker and ICD systems.

Given the potential for changes in device variables and programming, monitoring by device experts is necessary. Ann Intern Med. 2011;155:415-424.38Conclusie 2The decision to perform MRI in each patient with an implantable device should be made by balancing the potential benefit of MRI against the attendant risks.

Because thoracic MRI sequences have a greater effect on device variables and are more likely to result in artifacts, these sequences should be reserved for patients with an absolute clinical need.Ann Intern Med. 2011;155:415-424.39Magnasafe Registry (Russo ACC 2012)multicenter, prospective study designed to determine the frequency of major adverse clinical events and device parameter changes for 1500 patients with standard implantable cardiac electronic devices who undergo clinically-indicated, non-thoracic MRI at 1.5T.

Magnasafe 201240Magnasafe pts en methodsDevice interrogation pre- and post-MRI. Pacemaker-dependent subjects were programmed to an asynchronous pacing mode, and non-dependent subjects had pacing functions deactivated. For ICD patients, all therapies were programmed to off for those not pacing-dependent; ICD pacing-dependent ICD subjects were excluded. Primary study endpoints were device failure, generator/lead replacement, induced arrhythmia, loss of capture, or electrical reset. Secondary endpoints were clinically-relevant device parameter changes. No limits were placed on the number of repeat scans performedMagnasafe Results (1)April 2009-November 2011, 431 MRI studies (324 pacemakers, 107 ICDs) 88% 1 MRI, 12 meer dan 1 MRI

No deaths, device failures, generator/lead replacements, losses of capture, or ventricular arrhythmias occurred in either the Initial scan or Repeat scan groups.Magnasafe Results (2)Decrease in battery voltage 0.04V in 4 % of the Initial scan group and 0% of the Repeat scan group. Pacing lead impedance change 50 in 7 % of the Initial scan group, and 2% of the Repeat scan group. No decrease of 50% in R-wave or P-wave amplitude occurred.A pacing threshold increase 0.5V at 0.4 ms occurred in 2% in each group.Magnasafe ConclusionNo association between number of MRI scans and rate of clinical events or device parameter changes.

No deaths, device failures, generator/lead replacements, or losses of capture were noted after clinically-indicated non-thoracic MRI at 1.5TIs de huidige MRI-unsafe pacemaker/ICD MRI-safe?> 1000 patienten MRIICD zowel als pacemakersPacemaker afhankelijkThoracic MRI/extra thoracic MRI

Protocol volgens Nazarian is veiligWaarom geen MRI safe device (1)?Hoeveel mag een nieuwe feature kosten?Boston Scientific: fineline draden sinds 2000 geimplanteerd hebben MRI approvalBoston Scientific rekent niets extras voor MRI safe pacemaker/ICDMedtronic: onhandige MRI safe draden (mijn mening)SSIR bestaat bij mijn weten niet, MRI safe is 2 kamersysteem met 2 draden, ook bij AAI/VVI pacing indicatie

Waarom geen MRI safe device (2)?Biotronik pacing draden: dik en onhandig (mijn mening).Onderlinge uitwisselbaarheid: geen firma is bereid te garanderen dat andere draden op eigen device ook MRI safe combinatie is (persoonlijke ervaring met Biotronik draden en Medtronic Surescan PG)Nieuwe technologie/nieuwe lead: weer een Riata?

Waarom geen MRI safe device (3)?Oude leads: alleen BSc Fineline retrograde CE markeringBiotronik, listprijs A en V lead + 100-150 euro, nog alleen MR-conditional devices?Medtronic?St Jude SR +5%, DR + 3.5%, lead + 53%, geen CRTD/ICDBoston SR +6,6% DR +5,8% lead Fineline retrogr CE

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