title: Prevention of ventricular desynchronization by permanent para-Hisian pacing after atrioventricular node ablation in chronic atrial fibrillation: a crossover, blinded, randomized study versus apical right ventricular pacing.
abstract: OBJECTIVE
  The aim of our study was to evaluate the feasibility, the safety, and hemodynamic improvements induced by permanent para-Hisian pacing in patients with chronic atrial fibrillation and narrow QRS who underwent atrioventricular (AV) node ablation.
  
  
  BACKGROUND
  Right ventricular apical pacing, inducing asynchronous ventricular contraction, may impair cardiac function; permanent para-Hisian pacing could preserve interventricular synchrony and improve left ventricular function.
  
  
  METHODS
  After AV node ablation, 16 patients were implanted with a dual-chamber pacemaker connected to a screw-in lead positioned in close proximity to the His bundle and to a right ventricular apical lead. Clinical and echocardiographic data were collected at baseline and after two randomized six-month periods (with para-Hisian and conventional pacing).
  
  
  RESULTS
  During para-Hisian pacing, the interventricular electromechanical delay improved as well (34 +/- 18 ms) as during right apical pacing (47 +/- 19 ms), p < 0.05. Para-Hisian pacing allowed an improvement in New York Heart Association functional class (1.75 +/- 0.4 vs. 2.33 +/- 0.6 at baseline and 2.5 +/- 0.4 during apical pacing, p < 0.05 for both), in quality-of-life score (16.2 +/- 8.7 vs. 32.5 +/- 15.0 at baseline, p < 0.05), and in the 6-min walk test (431 +/- 73 m vs. 378 +/- 60 m at baseline and 360 +/- 71 m during apical pacing, p < 0.5 for both). Mitral and tricuspid regurgitation improved during para-Hisian pacing (1.22 +/- 0.8 and 1.46 +/- 0.5 index, respectively, vs. 1.68 +/- 0.6 [p < 0.05] and 1.62 +/- 0.7 [p = NS] index at baseline, respectively), with a slight worsening during apical pacing (1.93 +/- 1 and 1.93 +/- 0.7 index, respectively, p < 0.05 for both).
  
  
  CONCLUSIONS
  Permanent para-Hisian pacing is feasible and safe. Compared with conventional right apical pacing, it allows an improvement in functional and hemodynamic parameters over long-term follow-up.
authors.affiliation: Divisione Clinicizzata di Cardiologia, Facoltà di Medicina e Chirurgia di Novara, Università degli Studi del Piemonte Orientale, Novara, Italy.
authors.forename: Eraldo
authors.initials: E
authors.lastname: Occhetta
authors.forename: Miriam
authors.initials: M
authors.lastname: Bortnik
authors.forename: Andrea
authors.initials: A
authors.lastname: Magnani
authors.forename: Gabriella
authors.initials: G
authors.lastname: Francalacci
authors.forename: Cristina
authors.initials: C
authors.lastname: Piccinino
authors.forename: Laura
authors.initials: L
authors.lastname: Plebani
authors.forename: Paolo
authors.initials: P
authors.lastname: Marino
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D001281:Atrial Fibrillation / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D001283:Atrioventricular Node; D002036:Bundle of His; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods*; D017115:Catheter Ablation / Q000009:adverse effects; D002908:Chronic Disease; D018592:Cross-Over Studies; D004562:Electrocardiography; D017079:Exercise Tolerance; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000209:etiology; D011788:Quality of Life; D016037:Single-Blind Method; D016896:Treatment Outcome; D014262:Tricuspid Valve Insufficiency / Q000209:etiology; D018487:Ventricular Dysfunction, Left / Q000150:complications