Selective atrionodal input ablation for induction of proximal complete heart block with stable junctional escape rhythm in patients with uncontrolled atrial fibrillation.
BACKGROUND
The study tests the hypothesis that ablating all inputs to the atrioventricular (AV) node can result in complete heart block with stable junctional escape rhythm.


RESULTS
We attempted atrionodal input ablation in 76 consecutive patients with uncontrolled atrial fibrillation. Fast and slow pathways were first ablated. If there was no AV block, additional energy applications were done between fast and slow pathway locations. The patients were followed for 42 +/- 11 months. Group I (n = 57) comprised patients with complete heart block and junctional escape rhythm (53 +/- 4 beats/min) at the end of the procedure. The escape rhythm remained stable throughout follow-up. Group II (n = 15) were patients who failed the stepwise atrionodal input ablation and required AV junctional ablation guided by His bundle potential to achieve complete heart block. Four patients showed a slow escape rhythm after ablation (33 +/- 4 beats/min). Others had no escape rhythm. All 15 pts remained pacemaker dependent. The total death rate of groups I and II was 18/57 (31.6%) vs 10/15 (66.7%), respectively (p < 0.02). These differences could not be explained by a difference of left ventricular ejection fraction (0.42 +/- 0.07 vs 0.41 +/- 0.04, respectively, p = NS).


CONCLUSIONS
(1) In most patients, ablation of both fast and slow pathways did not result in complete heart block, indicating the presence of multiple atrionodal inputs. (2) Ablation of all atrionodal inputs may result in complete heart block with stable junctional escape rhythm. (3) As compared with AV junctional ablation, atrionodal input ablation was associated with a lower mortality rate on long-term follow up.
Strohmer
Bernhard
B
Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, CA, USA. B.Strohmer@lks.at
Hwang
Chun
C
Peter
C Thomas
CT
Chen
Peng-Sheng
PS
D000368:Aged; D001281:Atrial Fibrillation / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D001283:Atrioventricular Node / Q000473:pathology* / Q000601:surgery*; D017115:Catheter Ablation; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology; D004452:Echocardiography; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005500:Follow-Up Studies; D006327:Heart Block / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D006329:Heart Conduction System / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D010138:Pacemaker, Artificial; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology; D016019:Survival Analysis; D013995:Time; D016896:Treatment Outcome; D014481:United States; D016277:Ventricular Function, Left / Q000502:physiology