title: Comparison of noncontact and electroanatomic mapping to identify scar and arrhythmia late after the Fontan procedure.
abstract: BACKGROUND
  The right atrium late after the Fontan procedure is characterized by multiple complex arrhythmia circuits. We performed simultaneous electroanatomic and noncontact mapping to assess the accuracy of both systems to identify scar and arrhythmia.
  
  
  RESULTS
  Mapping was performed in 26 patients aged 26.8+/-8.9 years, 18.7+/-4.4 years after Fontan surgery. The area and site of abnormal endocardium defined by electroanatomic mapping (bipolar contact electrogram <0.5 mV) were compared with those defined by noncontact mapping during sinus rhythm and by dynamic substrate mapping. Contact and reconstructed unipolar electrograms at a known distance from the multielectrode array, recorded by the noncontact system simultaneously at 452 endocardial sites, were compared for morphological cross correlation, timing difference, and amplitude. Mapping of arrhythmias was performed with both systems when possible. The median patient abnormal endocardium as defined by electroanatomic mapping covered 38.0% (range 16.7% to 97.8%) of the right atrial surface area, as opposed to 60.9% (range 21.3% to 98.5%) defined by noncontact mapping during sinus rhythm and 11.9% (range 0.4% to 67.3%) by dynamic substrate mapping. A significant decrease in electrogram cross correlation (P=0.003), timing (P=0.012), and amplitude (P=0.003) of reconstructed electrograms, but not of contact electrograms (P=0.742), was seen at endocardial sites >40 mm from the multielectrode array. Successful arrhythmia mapping by electroanatomic versus noncontact mapping was superior in 15 patients (58%), the same in 6 (23%), and inferior in 5 (19%; P=0.044).
  
  
  CONCLUSIONS
  Electroanatomic mapping is the superior modality for arrhythmia mapping late after the Fontan procedure. Noncontact mapping is limited by a significant reduction in reconstructed electrogram correlation, timing, and amplitude >40 mm from the multielectrode array and cannot accurately define areas of scar and low-voltage endocardium.
authors: Department of Cardiac Electrophysiology, St Bartholomew's Hospital, London, EC1A 7BE, United Kingdom.
authors: Dominic J
authors: DJ
authors: Abrams
authors: Mark J
authors: MJ
authors: Earley
authors: Simon C
authors: SC
authors: Sporton
authors: Peter M
authors: PM
authors: Kistler
authors: Michael A
authors: MA
authors: Gatzoulis
authors: Michael J
authors: MJ
authors: Mullen
authors: Janice A
authors: JA
authors: Till
authors: Seamus
authors: S
authors: Cullen
authors: Fiona
authors: F
authors: Walker
authors: Martin D
authors: MD
authors: Lowe
authors: John E
authors: JE
authors: Deanfield
authors: Richard J
authors: RJ
authors: Schilling
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D000638:Amiodarone / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy; D016280:Atrial Function, Right; D006328:Cardiac Catheterization / Q000295:instrumentation / Q000379:methods*; D017115:Catheter Ablation; D002921:Cicatrix / Q000473:pathology / Q000503:physiopathology*; D003131:Combined Modality Therapy; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D004351:Drug Resistance; D004562:Electrocardiography; D004566:Electrodes; D004699:Endocardium / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D018729:Fontan Procedure / Q000009:adverse effects* / Q000379:methods; D006325:Heart Atria / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008955:Models, Cardiovascular; D009929:Organ Size; D011184:Postoperative Period; D011312:Pressure; D011652:Pulmonary Circulation; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery; D013610:Tachycardia / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D014683:Vena Cava, Superior / Q000503:physiopathology / Q000601:surgery
chemical_list: D000638:Amiodarone