title: Role of echocardiographic dyssynchrony parameters in predicting response to cardiac resynchronization therapy.
abstract: OBJECTIVE
  In the present study, we compare different echocardiographic cardiac dyssynchrony parameters, both of intraventricular and interventricular dyssynchrony, in order to predict response to cardiac resynchronization therapy (CRT).
  
  
  RESULTS
  In a population of 77 heart failure patients scheduled for CRT, we measured the interventricular mechanical delay (IVMD) and we analyzed six different parameters of intraventricular dyssynchony: the tissue Doppler imaging (TDI) septum-lateral wall delay, the systolic dyssynchrony index; the three-dimensional SD of the time to reach minimum systolic volume for 16 left ventricular segments (3D-SDI); the speckle-tracking radial, circumferential and longitudinal dyssynchrony. At 6 months of follow-up, 61 (79%) patients were responders (≤15% in left ventricular end-systolic volume). On baseline analysis, 3D-SDI, radial strain, longitudinal strain and circumferential strain and IVMD were significantly higher in responder group (10.8 ± 3.9 vs. 7.6 ± 1.8% for 3D-SDI; P = 0.003; 212 ± 91 vs. 125 ± 36 ms for radial strain, P = 0.0003; 185 ± 83 vs. 134 ± 53 ms for longitudinal strain, P = 0.02; 190 ± 80 vs. 130 ± 54 ms for circumferential strain, P = 0.006; 45 ± 21 vs. 30 ± 20 ms for IVMD; P = 0.01). On univariate and multivariate analysis, only IVMD was significantly associated with a complete echocardiographic response to CRT. 3D-SDI and radial strain present the better values of sensitivity and specificity, overall if associated to an evaluation of IVMD (sensitivity 76%, specificity 88%, for 3D-SDI + IVMD; sensitivity 80% and specificity 85% for radial strain + IVMD).
  
  
  CONCLUSIONS
  The novel parameters, such as 3D-SDI and speckle-tracking (particularly radial strain), offer better diagnostic accuracy in identifying patients who are responders to CRT. The addition of the contemporary parameter of IVMD improves the diagnostic accuracy.
authors.affiliation: aDivision of Cardiology, SS Trinità Borgomanero Hospital bElectrophysiology and Cardiostimulation Laboratory, Policlinico di Monza Group cMedical Direction, SS Trinità Borgomanero Hospital, Novara, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Maffè
authors.forename: Paola
authors.initials: P
authors.lastname: Paffoni
authors.forename: Pierfranco
authors.initials: P
authors.lastname: Dellavesa
authors.forename: Antonello
authors.initials: A
authors.lastname: Perucca
authors.forename: Daniela
authors.initials: D
authors.lastname: Kozel
authors.forename: Anna M
authors.initials: AM
authors.lastname: Paino
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cucchi
authors.forename: Franco
authors.initials: F
authors.lastname: Zenone
authors.forename: Luca
authors.initials: L
authors.lastname: Bergamasco
authors.forename: Nicolò Franchetti
authors.initials: NF
authors.lastname: Pardo
authors.forename: Fabiana
authors.initials: F
authors.lastname: Signorotti
authors.forename: Lara
authors.initials: L
authors.lastname: Baduena
authors.forename: Umberto
authors.initials: U
authors.lastname: Parravicini
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D015150:Echocardiography, Doppler / Q000379:methods; D019560:Echocardiography, Three-Dimensional / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology