title: DDD versus VVIR pacing in patients, ages 70 and over, with complete heart block.
abstract: BACKGROUND
  Dual-chamber pacing is believed to have an advantage over single-chamber ventricular pacing. The aim of the study was to determine whether elderly patients with implanted pacemaker for complete atrioventricular block gain significant benefit from dual-chamber (DDD) compared with single-chamber ventricular demand (VVIR).
  
  
  METHODS
  The study was designed as a double-blind randomized two-period crossover study-each pacing mode was maintained for 3 months. Thirty patients (eight men, mean age 76.5 +/- 4.3 years) with implanted PM were submitted to a standard protocol, which included an interview, functional class assessment, quality of life (QoL) questionnaires, 6-minute walk test, and transthoracic echocardiographic examinations. QoL was measured by the SF-36. All these parameters were obtained on DDD mode pacing and VVIR mode pacing. Paired data were compared.
  
  
  RESULTS
  QoL was significantly different between the two groups and showed the best values in DDD. Overall, no patient preferred VVIR mode, 18 preferred DDD mode, and 12 expressed no preference. No differences in mean walking distances were observed between patients with single-chamber and dual-chamber pacing. VVI pacing elicited marked decrease in left ventricle ejection fraction and significant enlargement of the left atrium. DDD pacing resulted in significant increase of the peak systolic velocities in lateral mitral annulus and septal mitral annulus. Early diastolic velocities on both sides of mitral annulus did not change.
  
  
  CONCLUSIONS
  In active elderly patients with complete heart block, DDD pacing is associated with improved quality of life and systolic ventricular function compared with VVI pacing.
authors.affiliation: Department of Cardiology, Sahloul Hospital, Sousse, Tunisia. sanaouali@hotmail.fr
authors.forename: Sana
authors.initials: S
authors.lastname: Ouali
authors.forename: Elyes
authors.initials: E
authors.lastname: Neffeti
authors.forename: Karima
authors.initials: K
authors.lastname: Ghoul
authors.forename: Sami
authors.initials: S
authors.lastname: Hammas
authors.forename: Slim
authors.initials: S
authors.lastname: Kacem
authors.forename: Rim
authors.initials: R
authors.lastname: Gribaa
authors.forename: Fahmi
authors.initials: F
authors.lastname: Remedi
authors.forename: Essia
authors.initials: E
authors.lastname: Boughzela
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D018592:Cross-Over Studies; D005260:Female; D006327:Heart Block / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D011446:Prospective Studies; D011788:Quality of Life; D014463:Ultrasonography; D016138:Walking