title: Left ventricular performance during para-His pacing in patients with high-grade atrioventricular block: an acute study.
abstract: OBJECTIVE
  To compare changes in left ventricular (LV) performance and mechanical synchrony between atrial-based pacing with intrinsic conduction (AAI), dual-chamber para-His Pacing (DDD-PHP) and dual-chamber right ventricular septal pacing (DDD-RVS) in patients with high-grade atrioventricular block (AVB).
  
  
  RESULTS
  Patients with high-grade AVB and QRS <120 ms, who had temporary intrinsic atrioventricular (AV) conduction the day after the implantation were included in the study. All patients received a biventricular pacemaker with a para-His lead in the LV port, and a RVS lead in the right ventricular port. Left ventricular three-dimensional echocardiograms, LV outlet tract-velocity time integrals (LVOT-VTI), and LV synchrony with tissue Doppler imaging were recorded during AAI, DDD-PHP, and DDD-RVS. Eleven patients were included. The mean LVOT-VTI was significant lower during DDD-RVS (19.2 ± 5.5 cm) as compared with DDD-PHP (21.4 ± 5.5 cm), P = 0.006 and AAI (21.6 ± 6.8 cm), P = 0.016. The LVEF was higher during AAI than during DDD-PHP (P= 0.02) and DDD-RVS (P< 0.01). The maximal time to peak velocity between basal segments was significant longer with DDD-RVS (95 ± 26 ms) than with AAI (72 ± 30 ms), P = 0.028, whereas no difference was observed between AAI and DDD-PHP (81 ± 42 ms), P = 0.20.
  
  
  CONCLUSIONS
  Acutely, DDD-PHP preserves LV systolic performance and mechanical synchrony as compared with DDD-RVS.
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Skejby, Bendstrupgaardsvej 100, DK-8200 Aarhus N, Denmark. mads.brix.kronborg@ki.au.dk
authors.forename: Mads Brix
authors.initials: MB
authors.lastname: Kronborg
authors.forename: Steen Hvitfeldt
authors.initials: SH
authors.lastname: Poulsen
authors.forename: Peter Thomas
authors.initials: PT
authors.lastname: Mortensen
authors.forename: Jens Cosedis
authors.initials: JC
authors.lastname: Nielsen
mesh_terms: D000208:Acute Disease; D000368:Aged; D054537:Atrioventricular Block / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy*; D001919:Bradycardia / Q000517:prevention & control; D002036:Bundle of His / Q000502:physiology*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011690:Purkinje Fibers / Q000502:physiology; D012720:Severity of Illness Index; D013599:Systole / Q000502:physiology; D014463:Ultrasonography; D016277:Ventricular Function, Left / Q000502:physiology*; D016278:Ventricular Function, Right / Q000502:physiology