title: Velocity vector imaging in assessing myocardial systolic function of hypertensive patients with left ventricular hypertrophy.
abstract: BACKGROUND
  To date, most studies about strain and strain rate (SR) are based on Doppler tissue imaging (DTI), which is dependent on the angle between ultrasonic scan line and tissue. Velocity vector imaging (VVI) is a new echocardiographic method based on two-dimensional gray scale imaging, which is angle-independent and can provide more information about cardiac function than DTI.
  
  
  OBJECTIVE
  To assess regional myocardial SR in hypertensive patients with left ventricular hypertrophy (LVH) but normal global ejection fraction (GEF) and fractional shortening (FS) using VVI.
  
  
  METHODS
  Using VVI, two-dimensional images were performed in 20 hypertensive patients with LVH and 20 normal control subjects. The segmental systolic peak SR (SRs) in the short-axis view and the apical SRs in the long-axis view were analyzed by offline software.
  
  
  RESULTS
  The segmental SRs in the long-axis and short-axis views were significantly lower in the LVH group than in the corresponding segments of the control group. There was no significant difference between the circumferential SRs of different segments in the short-axis view in the LVH and control groups. The circumferential SRs decreased significantly from the endocardium to the middle layer of the myocardium in the short-axis view in the LVH group and in the control group.
  
  
  CONCLUSIONS
  Hypertensive patients with LVH may have regional LV systolic function impairment despite having normal GEF and FS. The GEF and FS were not the decisive factors of myocardial systolic function in the present study. There was an obvious systolic gradient from the endocardium to the middle layer of myocardium in circumferential SRs in the short-axis view. VVI can be used to accurately recognize and quantify abnormalities of regional myocardial deformation.
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China.
authors.forename: Junhong
authors.initials: J
authors.lastname: Chen
authors.forename: Tiesheng
authors.initials: T
authors.lastname: Cao
authors.forename: Yunyou
authors.initials: Y
authors.lastname: Duan
authors.forename: Lijun
authors.initials: L
authors.lastname: Yuan
authors.forename: Zuojun
authors.initials: Z
authors.lastname: Wang
mesh_terms: D016022:Case-Control Studies; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000000981:diagnostic imaging*; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D013599:Systole