title: Real-time magnetic resonance imaging guidance improves the diagnostic yield of endomyocardial biopsy.
abstract: BACKGROUND
  Diagnostic yield of endomyocardial biopsy is low, particularly in disease that affects the myocardium in a non-uniform distribution. We hypothesized that real-time MRI guidance could improve the yield through targeted biopsy of focal myocardial pathology.
  
  
  METHODS
  An animal model of focal myocardial pathology was created by infusing 3mL of fluorescent microspheres (NuFlow Hydrocoat, 15μm diameter, 5 million spheres/mL) followed by 2mL of 100% ethanol to a branch coronary artery. Animals were survived for minimum 14days, before undergoing MRI guided endomyocardial biopsy using a custom 6.5Fr active visualization MRI-conditional bioptome and X-ray guided biopsy using a commercial bioptome. Specimens were analyzed using a dissecting microscope under ultraviolet light to determine the proportion of 'on-target' specimens containing fluorescent microspheres.
  
  
  RESULTS
  A total of 77 specimens were obtained using real-time MRI guidance and 87 using X-ray guidance, in five animals. Specimens obtained with the MRI-conditional bioptome were smaller compared with the commercial X-ray bioptome. Real-time MRI guidance significantly increased the diagnostic yield of endomyocardial biopsy (82% vs. 56% on-target biopsy specimens with real-time MRI vs. X-ray guidance, p<0.01).
  
  
  CONCLUSIONS
  Endomyocardial biopsy performed using real-time MRI guidance is feasible and significantly improves the diagnostic yield compared with X-ray fluoroscopy guidance.
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Toby
authors.initials: T
authors.lastname: Rogers
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Kanishka
authors.initials: K
authors.lastname: Ratnayaka
authors.affiliation: MRI Interventions, Irvine, CA and subsequently Russell H. Morgan Department of Radiology and Radiological Sciences, Division of MRI Research, John's Hopkins University, 600 North Wolfe Street, Park Building, Room #311, Baltimore, MD.
authors.forename: Parag
authors.initials: P
authors.lastname: Karmarkar
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Adrienne E
authors.initials: AE
authors.lastname: Campbell-Washburn
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: William H
authors.initials: WH
authors.lastname: Schenke
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Mazal
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA; Institute of Biomedical Engineering, Bogazici University, Istanbul, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Kocaturk
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Anthony Z
authors.initials: AZ
authors.lastname: Faranesh
authors.affiliation: Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lederman