title: Different effects of cardiac resynchronization therapy on left atrial function in patients with either idiopathic or ischaemic dilated cardiomyopathy: a two-dimensional speckle strain study.
abstract: OBJECTIVE
  In dilated cardiomyopathy (DCM), attenuation of left atrial (LA) booster pump function has been observed, and attributed both to altered LA loading conditions owing to left ventricular (LV) diastolic dysfunction and to LA involvement in the myopathic process. The aim of the present study was to detect LA systolic dysfunction in DCM using speckle-tracking two-dimensional strain echocardiography (2DSE), and to assess the effects of cardiac resynchronization therapy (CRT) on LA myocardial strain during 6 month follow-up.
  
  
  RESULTS
  A total of 90 patients (aged, 52.4 +/- 10.2 years) with either idiopathic (n = 47) or ischaemic (n = 43) DCM underwent standard Doppler echo and 2DSE analysis of atrial longitudinal strain in the basal segments of LA septum and LA lateral wall, and in LA roof. The two groups were comparable for clinical variables (NYHA class: III in 72.2%; IV in 27.8%). LV volumes, ejection fraction, stroke volume, and mitral valve effective regurgitant orifice were similar between the two groups. No significant differences were evidenced in Doppler transmitral inflow measurements. LA diameter and maximal volume were also similar between the two groups. Conversely, LA active emptying volume and fraction were both lower in patients with idiopathic DCM. Peak systolic myocardial atrial strain was significantly compromised in patients with idiopathic DCM compared with ischaemic DCM in all the analysed atrial segments (P < 0.001). At follow-up, 64 patients (71.1%) (37 idiopathic and 27 ischaemic) were responders, and 26 (28.9%) (10 idiopathic; 16 ischaemic) were non-responders to CRT (responder: decrease of LV end-systolic volume >15%). A significant improvement in LA systolic function was obtained only in patients with ischaemic DCM responders to CRT (P < 0.001). By multivariable analysis, in the overall population, it was found that ischaemic aetiology of DCM (beta-coefficient = 0.62; P < 0.0001) and positive response to CRT (beta-coefficient = 0.42; P < 0.01) were the only independent determinants of LA lateral wall systolic strain.
  
  
  CONCLUSIONS
  Two-dimensional strain represents a promising non-invasive technique to assess LA atrial myocardial function in patients with DCM. LA pump and reservoir function at baseline and after CRT are more depressed in idiopathic compared with ischaemic DCM patients. Future longitudinal studies are warranted to understand further the natural history of LA myocardial function, the extent of reversibility of LA dysfunction with CRT, and the possible prognostic impact of such indexes in patients with congestive heart failure.
authors.affiliation: Monaldi Hospital, Second University of Naples, Via G. Martucci 35, 80121 Naples, Italy. antonellodandrea@libero.it
authors.forename: Antonello
authors.initials: A
authors.lastname: D'Andrea
authors.forename: Pio
authors.initials: P
authors.lastname: Caso
authors.forename: Silvio
authors.initials: S
authors.lastname: Romano
authors.forename: Raffaella
authors.initials: R
authors.lastname: Scarafile
authors.forename: Lucia
authors.initials: L
authors.lastname: Riegler
authors.forename: Gemma
authors.initials: G
authors.lastname: Salerno
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Limongelli
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Salvo
authors.forename: Paolo
authors.initials: P
authors.lastname: Calabrò
authors.forename: Luca
authors.initials: L
authors.lastname: Del Viscovo
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Romano
authors.forename: Ciro
authors.initials: C
authors.lastname: Maiello
authors.forename: Lucio
authors.initials: L
authors.lastname: Santangelo
authors.forename: Sergio
authors.initials: S
authors.lastname: Severino
authors.forename: Sergio
authors.initials: S
authors.lastname: Cuomo
authors.forename: Maurizio
authors.initials: M
authors.lastname: Cotrufo
authors.forename: Raffaele
authors.initials: R
authors.lastname: Calabrò
mesh_terms: D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D002302:Cardiac Output / Q000502:physiology; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000503:physiopathology; D016022:Case-Control Studies; D015150:Echocardiography, Doppler / Q000379:methods; D025401:Echocardiography, Stress / Q000379:methods; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D013599:Systole / Q000502:physiology