Effects of global longitudinal strain and total scar burden on response to cardiac resynchronization therapy in patients with ischaemic dilated cardiomyopathy.
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.
D'Andrea
Antonello
A
Department of Cardiology, Second University of Naples, Martucci 35, 80121 Naples, Italy. antonellodandrea@libero.it
Caso
Pio
P
Scarafile
Raffaella
R
Riegler
Lucia
L
Salerno
Gemma
G
Castaldo
Francesca
F
Gravino
Rita
R
Cocchia
Rosangela
R
Del Viscovo
Luca
L
Limongelli
Giuseppe
G
Di Salvo
Giovanni
G
Ascione
Luigi
L
Iengo
Raffaele
R
Cuomo
Sergio
S
Santangelo
Lucio
L
Calabrò
Raffaele
R
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