title: Contrast-enhanced CMR in patients after percutaneous closure of the left atrial appendage: a pilot study.
abstract: BACKGROUND
  To evaluate the feasibility and value of first-pass contrast-enhanced dynamic and post-contrast 3D CMR in patients after transcatheter occlusion of left atrial appendage (LAA) to identify incorrect placement and persistent leaks.
  
  
  METHODS
  7 patients with different occluder systems (n = 4 PLAATO; n = 2 Watchman; n = 1 ACP) underwent 2 contrast-enhanced (Gd-DOTA) CMR sequences (2D TrueFISP first-pass perfusion and 3D-TurboFLASH) to assess localization, artifact size and potential leaks of the devices. Perfusion CMR was analyzed visually and semi-quantitatively to identify potential leaks.
  
  
  RESULTS
  All occluders were positioned within the LAA. The ACP occluder presented the most extensive artifact size. Visual assessment revealed a residual perfusion of the LAA apex in 4 cases using first-pass perfusion and 3D-TurboFLASH indicating a suboptimal LAA occlusion.By assessing signal-to-time-curves the cases with a visually detected leak showed a 9-fold higher signal-peak in the LAA apex (567 ± 120% increase from baseline signal) than those without a leak (61 ± 22%; p < 0.03). In contrast, the signal increase in LAA proximal to the occluder showed no difference (leak 481 ± 201% vs. no leak 478 ± 125%; p = 0.48).
  
  
  CONCLUSIONS
  This CMR pilot study provides valuable non-invasive information in patients after transcatheter occlusion of the LAA to identify correct placement and potential leaks. We recommend incorporating CMR in future clinical studies to evaluate new device types.
authors: Department of Cardiovascular Imaging at Alice-Hospital, Darmstadt Radiology, Dieburger Strasse 29-31, Darmstadt, Germany. mohrs@radiologie-darmstadt.de
authors: Oliver K
authors: OK
authors: Mohrs
authors: Nina
authors: N
authors: Wunderlich
authors: Steffen E
authors: SE
authors: Petersen
authors: Anselm
authors: A
authors: Pottmeyer
authors: Hans-Ulrich
authors: HU
authors: Kauczor
mesh_terms: D000368:Aged; D016477:Artifacts; D020517:Atrial Appendage / Q000473:pathology*; D001281:Atrial Fibrillation / Q000473:pathology / Q000628:therapy*; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000295:instrumentation*; D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D006571:Heterocyclic Compounds; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009942:Organometallic Compounds; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D011475:Prosthesis Failure; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate