Pacemakers/défibrillateurs et IRM
Recommandations de l’interface SFR-SFC pour la bonne pratique
Estelle Gandjbakhch, Paris
Parc IRM - France
PM/ICD implantations in numbers
4 millions worldwide 1.2 millions patients in USA
∾ 400 000 patients in France
60 000-70 000 PM implantations /year 15 000 ICD implantations /year
2% increase /year
50% of PM/ICD carriers would need a MRI during follow-up *
Within one year follow-up, 17% of patients with PM/ICD would need a MRI**
*Roguin A. Europace 2008; 10: 336–346
**Sakakibara et al., Japanese Heart J 1999
IRM/PM evolution IRM/PM evolution
70 000 examens IRM / million habts 800 PM/million habts
- 1000 PM/million habtsen France
Bhuva AN et al. Eur Radiol 2020; 30:1378-84
Patients with PM/ICD have a difficult access to MRI Patients with PM/ICD have a difficult access to MRI
Exemple with ICDs – Source ACR
Turakhia M, Reynolds M, Wolff S, et al. Medtronic Data on File 2013. Data from 2011 MarketScan® Commercial and Medicare database, Truven Analysis, Inc. were used for this research.
Since development of conditional PM/IRM,
– Wrongly referred in France as
"compatible"
– Some trends to trivialize the use of PM/ICD in MRI
– Despite a non-zero risk
– especially with the development of high magnetic fields
And yet,
– Implanted patients are refuted in MRI at most MRI centers in
Europe
– An implanted patient is 50 times less likely to get an MRI VR
than a non-implanted one – Increased machine time – No financial recognition
Nazarian S et al. J Magn Res Imaging 2016; 43: 115-27
Two opposite tendencies
Les risques existent toujours
• Les risques sont moindres avec les systèmes MR conditionnels
– Dans les conditions d’utilisation recommandées
• L’expression pacemaker « IRM- compatible » est impropre
• Chaque séquence d’IRM est une nouvelle
« expérience » induisant un risque propre
– Patient
– Matériel implanté – Séquence
Main field (B0) Gradients RF field (B1)
Potentialrisk(s)
Force / Torque Vibration
Arrhythmias Surdetection Heating
Pacing inhibition PM/DAI malfunction (reset mode, battery depletion)
Multiparametric interactions Multiparametric interactions
ICD Tachycardia detection inhibition
Risks of MRI on PM/ICDs (conditional and non-conditional) Risks of MRI on PM/ICDs (conditional and non-conditional)
For the patient,
• Oversensing
– Pacing inhibition
– Bradycardia in pacing-dependent patient
– Inappropriate shock
• Ventricular arrhythmia
– Risk of asynchronous mode VOO, DOO (the main cause of death describe)
– Non-detection of ventricular arrhythmia (inhibition of ICD therapy)
• Burns (RF)
– abandoned leads
For the device,
• Migrating or moving components (Purely theoretical risk)
• Battery depletion
• Deprogramming
• Switching to Reversion Mode (VVI)
• Permanent failure
• Thresholds changes
There is no "MR safe" device
Magnasafe Regsitry
• 1500 patients
• 2/3 PM- 1/3 DAI
• IRM 1.5 T extra thoracic
• 0.3% in« back up » mode
• 1 mute ICD change
• Sensing/pacing thresholds modifications : non significant
John Hopkins Registry
• 1509 patients
• 58% PM- 48% DAI
• IRM 1.5 T thoracic /extra thoracic
• 0.5% in« back up » mode
• 1 mute PM (end of life battery)
• Sensing/pacing thresholds
modifications : 4% but non significant
Prospective registries of non MRI-conditional devices Prospective registries of non MRI-conditional devices
Nazarian et al. NEJM 2017 Russo et al. NEJM 2017
The latest reported deaths are related to old models The latest reported deaths are related to old models
• 6 deaths following MRI in patients with PM
• patients not monitored during the examination
• Risk contexts (SCA, advanced heart disease, hydro-electrolyte disorders)
• examined outside hospital, no cardiological supervision
• all not pacing-dependent
• Essential cause: VT, VF
• All standard field ≤ 1.5T
• The MRI department was not informed of the PM; communication +++
• No deaths reported in selected and monitored patients
Irnich W. Europace 2005; 7: 353-365
PM/DAI conditionnels
• Les risques sont minorés mais non nuls
– Surdétection
• Inhibition du pacing ou choc inapproprié
– Arythmie
• Mode asynchrone (VOO, DOO)
– Bradycardie
• Mode ODO, OOO
– Inactivation du DAI: non traitement d’une TV/FV
Gandjbakhch E et al. Arch Cardiovasc Dis.2020 Dacher JN et al. Diagn Interv Imaging 2020
•
Innovations technologiques– Sondes amagnétiques – Nouveaux interrupteurs
– Diminution de la composante ferro magnétique du générateur
• Determine if the system is IRM conditional
• Benefit/risk?
• Can MRI be substituable?
• No contra-indications
• Indication of PM/DAI
• Pacing-dependency?
• History of VA (ICD)
Prescription
• What mode?
• Where?
• Surveillance?
• Who? How?
Pre-MRI programming
MRI Post-MRI
programming
• Monitoring: Who? How?
• Reduce the number of sequences to the minimum
• Never exit the standard mode (SAR control)
• Restoration of standard settings and device control
• Where?
• Who? How?
Dedicated Protocols +++
Dedicated Protocols +++
Discussion with cardiologist
Gandjbakhch E et al. Arch Cardiovasc Dis.2020 Dacher JN et al. Diagn Interv Imaging 2020
Essential data Essential data
• Lead and can model: MR conditional?
• Pacing-dependent +++
• ICD
or PM• History of appropriate therapies for ICD
• No contra-indications:
– Abandoned leads/ epicardial leads/connectors : interrogate the patient, scars, chest Xray if necessary
– Device malfunction: elevated pacing thresholds, battery close to end of life
• Device implantation > 4-6 weeks (except emergencies)
• Clinical state of the patient: no fever or acute medical problem
Gandjbakhch E et al. Arch Cardiovasc Dis.2020 Dacher JN et al. Diagn Interv Imaging 2020
Determine if the system is MR conditional
www.irm-compatibilite.com
PM/ICD MR-conditional
Gandjbakhch E et al. Arch Cardiovasc Dis.2020 Dacher JN et al. Diagn Interv Imaging 2020
PM/ICD non MR-conditional
Gandjbakhch E et al. Arch Cardiovasc Dis.2020 Dacher JN et al. Diagn Interv Imaging 2020
Check list ++
Gandjbakhch E et al. Arch Cardiovasc Dis.2020 Dacher JN et al. Diagn Interv Imaging 2020
Organizational problem ++++
Time-consuming ++
Availability of device specialists Organization of MR departments No financial valuation
Patient Safety/
Risks associated to lack of access to MRI
No patient with implantable electrical cardiac devices should be formally contra-indicated from an MRI because of their device if the MR is vital
Patients Practitioners
Remaining issues
Devices Mode auto-detect
Que peut faire le radiologue pour réduire le risque?
• Respecter les indications – Guide de bon usage
• http://gbu.radiologie.fr
• Substituer l’IRM quand cela est possible (par la TDM en général)
• Quand l’IRM doit être faite
– Déterminer l’IRM compatibilité
• www.irm-compatibilite.com – Respecter les recommandations
constructeurs et se limiter à 1.5T/3T selon les modèles
– Monitorer le patient / médicaliser l’examen – Réduire le nombre de séquences au strict
minimum
– Ne jamais sortir du mode standard (contrôle du SAR)
• Communiquer au mieux avec la cardiologie +++ ( – Détecter les (rares) cas de CI
– Evaluer le bénéfice/risque de l’examen
Cas particulier de l’IRM cardiaque
• Les artéfacts liés aux DAI rendent illusoire la réalisation d’examens IRM cardiaques de qualité
• Une indication de DAI posée peut être une raison de réaliser une IRM en urgence
Perspectives
• Généralisation du mode d’auto-activation en mode IRM après détection du champ magnétique
limite le risque d’évènement pendant la reprogrammation en mode IRM
Facilite le circuit avant/après
• Délégation de taches /protocoles de coopération
• Simplification du parcours patient a l’échelon de chaque établissement : coordination entre
radiologues et cardiologues
Autres données essentielles
