MR imaging-guided electrophysiological ablation studies in humans with passive catheter tracking: initial results.
OBJECTIVE
To assess if real-time magnetic resonance (MR) imaging-guided radiofrequency (RF) ablation for atrial flutter is feasible in patients.


METHODS
The study complied with the Declaration of Helsinki and was approved by the local ethics committee. All patients were informed about the investigational nature of the procedures and provided written informed consent. Ten patients (six men; mean age ± standard deviation, 68 years ± 10) with symptomatic atrial flutter underwent isthmus ablation. In all patients, two MR imaging conditional steerable diagnostic and ablation catheters were inserted into the coronary sinus via femoral sheaths and into the right atrium with fluoroscopic guidance. The patients were then transferred to a 1.5-T whole-body MR imager for an ablation procedure, in which the catheters were manipulated by an electrophysiologist by using a commercially available interactive real-time steady-state free precession MR imaging sequence.


RESULTS
All catheters were placed in standard positions successfully. Furthermore, simple programmed stimulation maneuvers were performed. In one of 10 patients, a complete conduction block was performed with MR imaging guidance. In nine of 10 patients, creating only a small number of additional touch-up lesions was necessary to complete the isthmus block with conventional fluoroscopy (median, three lesions; interquartile range, two to four lesions).


CONCLUSIONS
Real-time MR imaging-guided placement of multiple catheters is feasible in patients, with subsequent performance of stimulation maneuvers and occasional complete isthmus ablation.
From the Departments of Radiology (M. Grothoff, L.L., C.L., J.H., L.H., M. Gutberlet), Electrophysiology (C.P., C.E., T.G., G.H., P.S.), and Obstetrics (J.H.), University of Leipzig Heart Center, Struempellstr 34, 04289 Leipzig, Germany; Imricor Medical Systems, Burnsville, Minn (S.W., T.L., D.S.); and Philips Healthcare, Hamburg, Germany (B.S.).
Matthias
M
Grothoff
Christopher
C
Piorkowski
Charlotte
C
Eitel
Thomas
T
Gaspar
Lukas
L
Lehmkuhl
Christian
C
Lücke
Janine
J
Hoffmann
Lysann
L
Hildebrand
Steve
S
Wedan
Thomas
T
Lloyd
Daniel
D
Sunnarborg
Bernhard
B
Schnackenburg
Gerhard
G
Hindricks
Philipp
P
Sommer
Matthias
M
Gutberlet
D000368:Aged; D001282:Atrial Flutter / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media; D004562:Electrocardiography; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D053783:Magnetic Resonance Imaging, Interventional; D008297:Male; D009942:Organometallic Compounds
D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol