title: [The impact of cardiac resynchronization therapy on left ventricular diastolic function evaluated by speckle tracking imaging in patients with dilated cardiomyopathy].
abstract: OBJECTIVE
  To investigate the effects of cardiac resynchronization therapy (CRT) on left ventricular (LV) diastolic function measured by speckle tracking imaging (STI) in patients with dilated cardiomyopathy (DCM).
  
  
  METHODS
  CRT was performed in 21 DCM patients [15 male, mean age: 61.2 ± 11.2 (49-82) years].LV synchronization, LV systolic function and LV diastolic function were evaluated with conventional echocardiography, tissue Doppler imaging and STI before and 6 months after CRT.NYHA heart function was also assessed. Clinic Response to CRT was defined as improvement of more than 1 NYHA class.Response to CRT in echocardiography was defined as ≥ 15% reduction in LV end systolic volume at 6 months post CRT.
  
  
  RESULTS
  There were 16 responders and 5 non-responders at 6 months post CRT.In terms of diastolic function, conventional echocardiography derived deceleration time was both prolonged in non-responders and responders. At 6 months post CRT, STI derived LV isovolumetric diastolic strain rate [(0.19 ± 0.11) /s vs.(0.14 ± 0.09)/s, P < 0.001] was significantly increased while early diastolic mitral valve blood flow velocity/left ventricular isovolumetric diastolic strain rate (680 ± 600 vs.787 ± 690, P < 0.04) was significantly reduced in responder group while remained unchanged in non-responder group.Furthermore, left ventricular isovolumetric diastolic strain rate negatively correlated with plasma brain natriuretic peptide level (r = -0.68, P < 0.05).
  
  
  CONCLUSIONS
  In CRT responders of DCM patients, LV diastolic function is significantly improved and this change could be detected more effectively by STI derived LV diastolic function parameters.
authors.affiliation: Heart Center, Wuxi Peoples' Hospital Affiliated to Nanjing Medical University, Wuxi 214023, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Lu
authors.forename: Min
authors.initials: M
authors.lastname: Dai
authors.forename: Da-jun
authors.initials: DJ
authors.lastname: Qian
authors.forename: Chang-ying
authors.initials: CY
authors.lastname: Zhang
authors.forename: Li-jun
authors.initials: LJ
authors.lastname: Cao
authors.affiliation: Email:ruxingw@aliyun.com.
authors.forename: Ru-xing
authors.initials: RX
authors.lastname: Wang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058406:Cardiac Resynchronization Therapy; D002311:Cardiomyopathy, Dilated / Q000628:therapy*; D003952:Diagnostic Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016277:Ventricular Function, Left