title: Effects of global longitudinal strain and total scar burden on response to cardiac resynchronization therapy in patients with ischaemic dilated cardiomyopathy.
abstract: OBJECTIVE
  To evaluate whether quantification of the extent of scarred left ventricular (LV) tissue by speckle-tracking strain echo (2DSE) can predict response to cardiac resynchronization therapy (CRT) in patients with ischaemic dilated cardiomyopathy (DCM).
  
  
  RESULTS
  Forty-five patients (58.3 +/- 8.3 years; 24 males) with ischaemic DCM scheduled for CRT, and 25 controls were studied. A week before implantation all the patients underwent standard Doppler echo, 2DSE, and contrast-enhanced magnetic resonance (MR). Clinical and echocardiographic evaluation was repeated 6 months after CRT. The patients were considered as responders to CRT if LV end-systolic volume decreased by 15%. In DCM patients, LV ejection fraction was 29.2 +/- 5.1%. By evaluating the 765 segments with MR, subendocardial infarct was identified in 17.0% and transmural infarct in 18.3%. With 2DSE, the average global longitudinal strain (GLS) was -23.1 +/- 3.6% in controls and -15.1 +/- 5.1% in DCM (P = 0.001). GLS showed a close correlation with total scar burden using MR (r = 0.64, P < 0.001). At follow-up, patients were subdivided into responders (n = 30; 66.7%) and non-responders (n = 15; 33.3%) to CRT. GLS was significantly different in non-responders than in responders (GLS: -10.4 +/- 5.1 in non-responders vs. -18.4 +/- 14% in responders, P < 0.001). In a multivariable analysis, GLS (P < 0.0001) and radial intraventricular dyssynchrony (P < 0.001) were powerful independent determinants of response to CRT.
  
  
  CONCLUSIONS
  GLS is strongly associated with total scar burden assessed by MR, and is an excellent independent predictor of response to CRT.
authors.affiliation: Department of Cardiology, Second University of Naples, 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: 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: Francesca
authors.initials: F
authors.lastname: Castaldo
authors.forename: Rita
authors.initials: R
authors.lastname: Gravino
authors.forename: Rosangela
authors.initials: R
authors.lastname: Cocchia
authors.forename: Luca
authors.initials: L
authors.lastname: Del Viscovo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Limongelli
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Salvo
authors.forename: Luigi
authors.initials: L
authors.lastname: Ascione
authors.forename: Raffaele
authors.initials: R
authors.lastname: Iengo
authors.forename: Sergio
authors.initials: S
authors.lastname: Cuomo
authors.forename: Lucio
authors.initials: L
authors.lastname: Santangelo
authors.forename: Raffaele
authors.initials: R
authors.lastname: Calabrò
mesh_terms: D000368:Aged; D000465:Algorithms; D002304:Cardiac Pacing, Artificial; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000628:therapy*; D002921:Cicatrix / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D011379:Prognosis; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging