title: Prevalence of E/A wave fusion and A wave truncation in DDD pacemaker patients with complete AV block under nominal AV intervals.
abstract: OBJECTIVE
  Optimization of the AV-interval (AVI) in DDD pacemakers improves cardiac hemodynamics and reduces pacemaker syndromes. Manual optimization is typically not performed in clinical routine. In the present study we analyze the prevalence of E/A wave fusion and A wave truncation under resting conditions in 160 patients with complete AV block (AVB) under the pre-programmed AVI. We manually optimized sub-optimal AVI.
  
  
  METHODS
  We analyzed 160 pacemaker patients with complete AVB, both in sinus rhythm (AV-sense; n = 129) and under atrial pacing (AV-pace; n = 31). Using Doppler analyses of the transmitral inflow we classified the nominal AVI as: a) normal, b) too long (E/A wave fusion) or c) too short (A wave truncation). In patients with a sub-optimal AVI, we performed manual optimization according to the recommendations of the American Society of Echocardiography.
  
  
  RESULTS
  All AVB patients with atrial pacing exhibited a normal transmitral inflow under the nominal AV-pace intervals (100%). In contrast, 25 AVB patients in sinus rhythm showed E/A wave fusion under the pre-programmed AV-sense intervals (19.4%; 95% confidence interval (CI): 12.6-26.2%). A wave truncations were not observed in any patient. All patients with a complete E/A wave fusion achieved a normal transmitral inflow after AV-sense interval reduction (mean optimized AVI: 79.4 ± 13.6 ms).
  
  
  CONCLUSIONS
  Given the rate of 19.4% (CI 12.6-26.2%) of patients with a too long nominal AV-sense interval, automatic algorithms may prove useful in improving cardiac hemodynamics, especially in the subgroup of atrially triggered pacemaker patients with AV node diseases.
authors.affiliation: Department of Cardiology and Angiology, Charité University Hospital, Berlin, Germany.
authors.forename: Wolfram C
authors.initials: WC
authors.lastname: Poller
authors.affiliation: Department of Cardiology and Angiology, Charité University Hospital, Berlin, Germany.
authors.forename: Henryk
authors.initials: H
authors.lastname: Dreger
authors.affiliation: Department of Cardiology and Angiology, Charité University Hospital, Berlin, Germany.
authors.forename: Marius
authors.initials: M
authors.lastname: Schwerg
authors.affiliation: Department of Cardiology and Angiology, Charité University Hospital, Berlin, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Melzer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D054537:Atrioventricular Block / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D015995:Prevalence; D012804:Sick Sinus Syndrome / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000503:physiopathology