title: Effects of variation of atrioventricular interval on left ventricular diastolic filling dynamics and atrial natriuretic peptide levels in patients with DDD pacing for complete heart block.
abstract: OBJECTIVE
  This study was designed to evaluate the effect of variation of atrioventricular (AV) interval (AVI) on left ventricular (LV) diastolic function and ANP and c-GMP levels during DDD pacing in patients with complete AV block and normal systolic function.
  
  
  METHODS
  The study population comprised 22 patients (mean age 65.2+/-14.3, 12 males) with complete AV block. All patients underwent complete Doppler echocardiography before implantation of a DDD-pacemaker. Twenty-four hours later, patients were paced for a period of 30 min, at three different AVIs (100 ms, 150 ms and 200 ms), at rest. During each pacing period, Doppler-derived LV diastolic indices were re-evaluated and ANP and c-GMP levels were reassessed.
  
  
  RESULTS
  Overall comparison showed a significant progressive augmentation, from 200 ms to 100 ms AVI, in transmitral E/A wave ratio (from 0.53+/-0.13 to 0.90+/-0.25, P = 0.0005) and in LV filling time (from 0.33+/-0.05 to 0.40+/-0.06s, P = 0.0005), followed by a significant progressive reduction in ANP and c-GMP levels. An AVI of 100 ms or 150 ms was associated with improved diastolic indices and lower natriuretic peptides levels, compared with the longer AVI.
  
  
  CONCLUSIONS
  Programmed AVI during DDD pacing affects LV diastolic performance and plasma ANP and c-GMP levels. The assessment of these parameters constitutes a useful modality for AVI optimization.
authors.affiliation: 1st Department of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Ioannis H
authors.initials: IH
authors.lastname: Styliadis
authors.forename: Nikolaos I
authors.initials: NI
authors.lastname: Gouzoumas
authors.forename: Haralambos I
authors.initials: HI
authors.lastname: Karvounis
authors.forename: Christodoulos E
authors.initials: CE
authors.lastname: Papadopoulos
authors.forename: Georgios K
authors.initials: GK
authors.lastname: Efthimiadis
authors.forename: Mihail
authors.initials: M
authors.lastname: Karamouzis
authors.forename: Georgios E
authors.initials: GE
authors.lastname: Parharidis
authors.forename: Georgios E
authors.initials: GE
authors.lastname: Louridas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D009320:Atrial Natriuretic Factor / Q000097:blood*; D001283:Atrioventricular Node / Q000503:physiopathology*; D002304:Cardiac Pacing, Artificial / Q000379:methods; D006152:Cyclic GMP / Q000097:blood; D003971:Diastole; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D006327:Heart Block / Q000097:blood / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D016277:Ventricular Function, Left
chemical_list: D009320:Atrial Natriuretic Factor; D006152:Cyclic GMP