title: Electrophysiological features and catheter ablation of symptomatic frequent premature atrial contractions.
abstract: OBJECTIVE
  Frequent premature atrial contractions (PACs) are associated with increased risk of atrial fibrillation (AF), stroke, and death. This study aimed to explore the electrophysiological features of PACs with and without inducing AF and to evaluate the effectiveness of catheter ablation for PACs.
  
  
  RESULTS
  Thirty-five consecutive patients with symptomatic, frequent, and drug-refractory PACs in the absence of AF (group A) and 35 patients with PACs-induced AF (group B) were enrolled. Coupling intervals (CoIs) of PACs were compared. Premature atrial contractions were mapped by the point-by-point and/or circular mapping technique. Focal ablation or pulmonary vein/superior vena cava isolation was applied as appropriate. A total of 35 ectopic foci were identified in group A. The majority of them were at pulmonary vein (PV) (n = 7), crista terminalis (n = 6), and para-Hisian area (n = 6). In group B, ectopic foci were in left-sided PVs in 21 patients, in right-sided PVs in 13 patients, and in SVC in 1 patient. There was significant difference in CoIs of PACs triggering AF and those from PVs and non-PV areas but without causing AF (362.8 ± 23.0 ms vs. 470.6 ± 60.1 ms vs. 515.6 ± 77.2 ms, P< 0.001). Premature atrial contractions were abolished in 32 of 35 patients from group A and in all patients from group B. At the end of follow-up, 29 patients in group A and 28 patients in group B were free of recurrence (off antiarrhythmic drugs) after the initial ablation (P =0.97).
  
  
  CONCLUSIONS
  Frequent PACs in the absence of AF were characterized as having their predilection sites and longer CoIs than those inducing AF. Catheter ablation was effective to eliminate symptomatic, frequent, and drug-refractory PACs.
authors.affiliation: Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, No. 1630 Dongfang Road, Shanghai 200127, China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, No. 1630 Dongfang Road, Shanghai 200127, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, No. 1630 Dongfang Road, Shanghai 200127, China.
authors.forename: Jialiang
authors.initials: J
authors.lastname: Mao
authors.affiliation: Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, No. 1630 Dongfang Road, Shanghai 200127, China.
authors.forename: Ben
authors.initials: B
authors.lastname: He
mesh_terms: D000200:Action Potentials; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D018880:Atrial Premature Complexes / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016022:Case-Control Studies; D017115:Catheter Ablation / Q000009:adverse effects; D018572:Disease-Free Survival; D015716:Electrocardiography, Ambulatory; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D012008:Recurrence; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents
keywords: Atrial fibrillation; Coupling interval; Focal ablation; Premature atrial contraction; Pulmonary vein isolation