title: Effect of cardiac resynchronization therapy on left atrial reverse remodeling: role of echocardiographic AV delay optimization.
abstract: OBJECTIVE
  Cardiac resynchronization therapy (CRT) improves left ventricular (LV) function in patients with advanced heart failure (HF) and there are some evidences about beneficial effects also on left atrial (LA) dimension and function. The contribution of atrioventricular delay (AVD) optimization on LA changes has not been evaluated. The purpose of the present study was to further investigate the effect of CRT on LA reverse remodelling and to evaluate the contribution of AVD optimization.
  
  
  RESULTS
  From the Cardiology Department of Piacenza Hospital and Modena University Hospital fifty one patients with refractory systolic HF and left bundle branch block were prospectively enrolled before CRT implantation. Patients were 1:1 randomized to either an optimized AVD (AV Opt group) determined by continuous wave Doppler aortic velocity-time integral (VTI) or an empiric AVD of 110 ms (AV Fixed group). Optimal AVD was defined as the AVD that yielded the largest aortic VTI at one of eight tested AV intervals (between 60 and 200 ms). LA volumes and emptying fractions were assessed by two-dimensional echocardiography at baseline and 6 months after CRT. At 6-month follow-up, CRT induced LA reverse remodeling in the whole population (maximal LA volume: 55.8 ± 16.4 ml/m² vs 50.3 ± 18.9 ml/m², p=0.006; pre-systolic LA volume: 47.0 ± 15.2 ml/m² vs 41.4 ± 17.4 ml/m², p=0.003; post-systolic LA volume: 36.4 ± 15.0 ml/m² vs 30.3 ± 18.0 ml/m(2), p=0.001); nevertheless, no substantial difference was observed about LA structural and functional remodeling between both AV Opt group and AV Fixed group.
  
  
  CONCLUSIONS
  CRT induces LA reverse remodeling that appears independent from AVD optimization.
authors.affiliation: Department of Cardiology, Guglielmo da Saliceto Hospital, Piacenza, Via Taverna 49, 29100 Piacenza, Italy. ale.malagoli@gmail.com
authors.forename: Alessandro
authors.initials: A
authors.lastname: Malagoli
authors.forename: Luca
authors.initials: L
authors.lastname: Rossi
authors.forename: Francesco
authors.initials: F
authors.lastname: Franchi
authors.forename: Massimo Francesco
authors.initials: MF
authors.lastname: Piepoli
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Malavasi
authors.forename: Edoardo
authors.initials: E
authors.lastname: Casali
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Modena
authors.forename: Giovanni Quinto
authors.initials: GQ
authors.lastname: Villani
mesh_terms: D000368:Aged; D064752:Atrial Remodeling / Q000502:physiology*; D001283:Atrioventricular Node / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging* / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D004452:Echocardiography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome