title: Reentrant and nonreentrant focal left atrial tachycardias occur after pulmonary vein isolation.
abstract: BACKGROUND
  Both focal and macroreentrant atrial tachycardia (ATs) can occur after pulmonary vein (PV) isolation for treatment of atrial fibrillation (AF). We report the response to pacing and pharmacologic maneuvers performed in patients with stable focal ATs after segmental PV isolation.
  
  
  OBJECTIVE
  The purpose of this study was to determine the mechanism of focal ATs occurring after PV isolation.
  
  
  METHODS
  Patients with persistent left AT after cessation of antiarrhythmic drug therapy presented for mapping and ablation. Electroanatomic mapping during AT was performed. Entrainment was performed from multiple right and left atrial sites. Single-beat resetting was performed. Adenosine was infused intravenously to determine the effect on the tachycardia.
  
  
  RESULTS
  Five patients (3 men and 2 women; age 65 +/- 10 years) had focal left AT that persisted in response to pacing maneuvers. Four patients had ATs (cycle length 265 +/- 18 ms) that demonstrated focal areas of early activation at the septal aspect of the right lower (3 patients) or right upper (1 patient) PV ostium. Resetting demonstrated a flat-plus increasing curve in two patients. Adenosine was infused with transient AV block and no change to the tachycardia cycle length in three patients. Tachycardias were entrained from multiple left atrial sites. Recordings from the ablation catheter at the critical isthmus typically demonstrated mid-diastolic or long fractionated potentials. One tachycardia with a longer and more variable cycle length (480-598 ms) did not demonstrate fusion during pacing from distant sites.
  
  
  CONCLUSIONS
  Persistent focal left ATs may occur after segmental PV isolation. Many of these tachycardias are caused by a focal reentrant circuit located at the PV ostium; however, focal nonreentrant rhythms also may occur.
authors.affiliation: Cardiovascular Division, University of Pennsylvania, 9 Founders Pavilion, 3400 Spruce Street, Philadelphia, PA 19104, USA. edward.gerstenfeld@uphs.upenn.edu
authors.forename: Edward P
authors.initials: EP
authors.lastname: Gerstenfeld
authors.forename: David J
authors.initials: DJ
authors.lastname: Callans
authors.forename: William
authors.initials: W
authors.lastname: Sauer
authors.forename: Jason
authors.initials: J
authors.lastname: Jacobson
authors.forename: Francis E
authors.initials: FE
authors.lastname: Marchlinski
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011667:Pulmonary Veins / Q000601:surgery*; D012307:Risk Factors; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000209:etiology* / Q000503:physiopathology; D014656:Vascular Surgical Procedures / Q000009:adverse effects*