title: Differential effect of ganglionic plexi ablation in a patient with neurally mediated syncope and intermittent atrioventricular block.
abstract: OBJECTIVE
  In patients with severe neurally mediated syncope (NMS), radiofrequency catheter ablation (RFA) of ganglionic plexi (GP) has been proposed as a new therapeutic approach. Cardio-inhibitory response during NMS is usually related to the sinoatrial (SA) and less frequently to atrioventricular (AV) node. Differential effect of GP ablation on SA and AV node is poorly understood.
  
  
  RESULTS
  We report a case of a 35-year-old female with frequent symptomatic episodes of advanced AV block treated by anatomically guided RFA at empirical sites of GPs. After RFA at the septal portion of the right atrium-superior vena cava junction, heart rate accelerated from 62 to 91 beats/min and PR interval prolonged from 213 to 344 ms. Sustained first-degree AV block allowed to observe directly the effects of subsequent RFA on the AV nodal properties. Subsequent RFA at right- and left-sided aspects of the inter-atrial septum had no further effect on heart rate and PR interval. Ablation at the inferior left GP was critical for restoration of normal AV conduction (final PR interval of 187 ms). No bradycardia episodes were observed by implantable loop recorder during the follow-up of 10 months and the patient was symptomatically improved.
  
  
  CONCLUSIONS
  This is the first clinical case showing the differential effect of GP ablation on SA and AV nodal function, and critical importance of targeting the GP at the postero-inferior left atrium. The successful procedure corroborates clinical utility of ablation treatment instead of pacemaker implantation in selected patients with cardio-inhibitory NMS.
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague 140 21, Czech Republic.
authors.forename: Masato
authors.initials: M
authors.lastname: Fukunaga
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague 140 21, Czech Republic dawi@ikem.cz.
authors.forename: Dan
authors.initials: D
authors.lastname: Wichterle
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague 140 21, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Peichl
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague 140 21, Czech Republic.
authors.forename: Bashar
authors.initials: B
authors.lastname: Aldhoon
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague 140 21, Czech Republic.
authors.forename: Robert
authors.initials: R
authors.lastname: Čihák
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague 140 21, Czech Republic.
authors.forename: Josef
authors.initials: J
authors.lastname: Kautzner
mesh_terms: D000200:Action Potentials; D000328:Adult; D054537:Atrioventricular Block / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001283:Atrioventricular Node / Q000503:physiopathology*; D017763:Autonomic Denervation / Q000379:methods*; D017115:Catheter Ablation; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005725:Ganglia, Autonomic / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D012008:Recurrence; D012720:Severity of Illness Index; D012849:Sinoatrial Node / Q000503:physiopathology*; D019462:Syncope, Vasovagal / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
keywords: Atrioventricular block; Autonomic regulations; Catheter ablation; Ganglionic plexi; Neurally mediated syncope