1. Real-Time MRI Guided Intervention Henry R. Halperin, M.D., M.A., F.A.H.A. Johns Hopkins University School of Medicine Departments of Medicine, Radiology, Biomedical Engineering Baltimore, MD USA

2. Presenter Disclosure Information Henry R Halperin, MD, MA Disclosure Information... The following relationships exist related to this presentation: Equity Interest: Lexmed, Significant Equity Interest: Surgivision, Modest Grant Support: RO1 HL64795, K24 HL04194, Significant Consulting Fees: Boston Scientific, Modest Off label use: Catheters in MRI, Gadolinium for cardiac studies

3. 3D Image Integration Current State of the Art

4. Pulmonary Vein Isolation: Atrial Fibrillation Ablation

5. Can Achieve ~100% PV Isolation 20-50% recurrence rate But:

6. Underestimation of Gaps: Lesions cannot be visualized directly Dong, Halperin, et al: Circulation. 2006;113:186-194. Gaps can have reversible conduction block !

7. Underestimation of Lesion Presence Conventional PVI using X-rays and Navx Pt moved to MRI scanner via transport system Viability imaging with MRI 40% of Navx marked ablation sites did not have lesions Rhode K, Knowles B, Razavi R: SCMR 2009

8. Real-Time MR Guided Intervention The Future and/or Now?

9. Rationale for Using MRI Accurate anatomy Visualize different kinds of soft tissue (ablated) Real-time 3-D imaging No ionizing radiation Similar cost as bi-plane x-ray system

10. Real-Time MR Guided Studies The technology

11. MRI Compatible Clinical Catheters ~ ~ 500 < Irvine Biomedical Inc IDE and IRB Approved Limited imaging power (SAR) Nazarian et al: Circulation. 2008 Jul 15;118(3):223-9

12. Improved MRI Compatible Catheters Susil et al: Mag Res Med, 47(3):584-600, 2002 ~ ~ 500 < SAR Amplification Factor Improved torque transmission (non-magnetic wire braid) Improved heating suppression

13. IEGM Recording During MR Imaging GE 1.5T CV/I Fiesta (SSFP) TR/TE 3.2/1.1 FA 45 o FOV 48x12cm ST 2cm 128x32 BW 128 kHz 10 frames/sec MRI compatible catheter in RV apex. IEGM

14. Intracardiac Electrograms (with multiple catheters) Outside Scanner Inside Scanner During Imaging HRA HBE RVA Nazarian et al: Circulation. 2008 Jul 15;118(3):223-9

15. Catheter Manipulation Using Real Time Imaging

16. Catheter Manipulation

17. Dynamic Heart with Real-Time Plane

18. MR Guided Studies What does it give us?

19. Lesion Visualization

20. Imaging Ablated Ventricular Tissue Pre Ablation Post Ablation Lardo et al, Circ 2000; 102(6):698-705

21. Gadolinium Lesion Enhancement Dickfeld et al, JACC, 2006;47:370-8

22. Accuracy of Lesion Size Estimates Contrast-VoidDelayed Enhancement Dickfeld et al, JACC, 2006;47:370-8

23. MRI Thermography (Proton precession rate (phase) is temperature sensitive) DEMRI Path Temperature Evolution

24. One Lesion Placed under MRI Guidance

25. LA Imaging Compared with Histology MR Image Histology MRIHistopathology R = 0.89, p < 0.001, n=20 Lardo et al, Circ 2000;102(6):698-705

26. Imaging LA Ablation Chronically Wylie J, Peters D, Josephson M, Manning W, et al: Heart Rhythm 2008;5:656–662

27. Imaging LA Ablation Chronically (after second procedure - completion of isolation) McGann C, Marrouche N, et al: J Am Coll Cardiol 2008;52:1263–71

28. Closing the Gaps in Linear Lesions Prediction of Conduction Block

29. Filling In Gaps and Conduction Block Pace Sense 20 ms Pace Sense Gap Open Gap Closed Pace Sense Conduction Block Sense Pace 40 ms

30. Real-Time MRI Guided Study in Patients IDE and IRB Approved

31. MR Guided EP Study Setup Conscious Sedation Monitoring O 2 Sat NIBP ECG Nazarian et al: Circulation. 2008 Jul 15;118(3):223-9

32. Real-Time MRI Guided EP Study Nazarian et al: Circulation. 2008 Jul 15;118(3):223-9

33. Summary MR can be used to guide catheter navigation in real time MR images can be obtained in real time during electrogram acquisition and during ablation Ablated tissue and true anatomy can be visualized Imaging characteristics may be able to predict the presence of conduction block This approach may improve safety and efficacy of many ablations Ablations in patients to start end of summer

34. Investigators Hiroshi Ashikaga Ergin Atalar Ronald Berger David Bluemke Paul Bottomley Hugh Calkins Timm Dickfeld Jun Dong Yoav Dori Rob Evers Owen Faris Ahmet Genc Michael Guttman Rozann Hansford Ritsushi Kato Lars Lickfett Aravindin Kolandeavelu Jennifer LaCorte Albert Lardo Joao Lima Elliot McVeigh Glenn Meininger Frank Miller Saman Nazarian Erez Nevo Nael Osman Ravi Ranjan Ariel Roguin Meiyappan Solaiyappan Robert Susil Menekhem Zviman