title: Transient ST-segment-elevation during pulmonary vein ablation using circumferential coiled microelectrodes in a prospective multi-centre study.
abstract: OBJECTIVE
  Paroxysmal atrial fibrillation (PAF) is predominantly triggered by focal ectopies located within the pulmonary veins (PV). The BITMAP Study (Breakthrough and Isolation Trial: Mapping and Ablation of Pulmonary Veins) investigated prospectively the safety and efficacy of a catheter design with circumferential mapping and ablation electrodes. We report the phenomenon of ST-segment-elevation during catheter placement in the left atrium (LA) and superior PVs in this multi-centre study.
  
  
  RESULTS
  Forty-three patients (57+/-10 years) with PAF were included in this study. Radiofrequency catheter (RFC) ablation supported by the 4F REVELATION Helix microcatheter (Cardima Inc., Freemont, CA, USA) with eight distal-coiled microelectrodes for bipolar mapping and ablation. RFC was applied at the ostial region of PV (30 W, 45-50 degrees C) with a maximum of four RFC applications per electrode. In four of the 43 patients from three centres, we recorded the occurrence of ST-segment-elevation greater than 0.2 mV and accompanying left thoracic discomfort. The ECG changes and the symptoms started abruptly and lasted for 4.2+/-2.2 min. Pericardial effusion could instantaneously be excluded by echocardiography in all cases. Coronary angiograms were performed in three patients with the longest episodes; no thrombotic material or air emboli were present. The symptoms and the ECG changes resolved completely in all patients.
  
  
  CONCLUSIONS
  The phenomenon of ST-segment-elevation during LA- and PV-mapping in patients with PAF may be a common occurrence. In this prospective multi-centre trial, we demonstrated the reversibility of this phenomenon; no cardiovascular or cerebral damage was reported during both the procedure and the follow-up. Although the mechanism is still unclear, vasospasm may contribute to this phenomenon because of autonomic dysregulation.
authors.affiliation: Department of Cardiology, University Hospital Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany. risius@uke.uni-hamburg.de
authors.forename: Tim
authors.initials: T
authors.lastname: Risius
authors.forename: Thorsten
authors.initials: T
authors.lastname: Lewalter
authors.forename: Berndt
authors.initials: B
authors.lastname: Lüderitz
authors.forename: Jörg O
authors.initials: JO
authors.lastname: Schwab
authors.forename: Stefan
authors.initials: S
authors.lastname: Spitzer
authors.forename: Claus
authors.initials: C
authors.lastname: Schmitt
authors.forename: Ernst
authors.initials: E
authors.lastname: Vester
authors.forename: Thomas
authors.initials: T
authors.lastname: Rostock
authors.forename: Thomas
authors.initials: T
authors.lastname: Meinertz
authors.forename: Stephan
authors.initials: S
authors.lastname: Willems
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000601:surgery*; D006328:Cardiac Catheterization; D017115:Catheter Ablation / Q000009:adverse effects* / Q000295:instrumentation; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000601:surgery*; D006801:Humans; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D011667:Pulmonary Veins