title: Doppler myocardial imaging in the diagnosis of early systolic left ventricular dysfunction in diabetic rats.
abstract: OBJECTIVE
  To find out if Doppler myocardial imaging (DMI) can detect early signs of left ventricular (LV) dysfunction in a rat model of diabetic cardiomyopathy.
  
  
  METHODS
  Eight control and 12 Streptozotocin (STZ)-induced diabetic rats underwent transthoracic echocardiography with high-resolution technology at baseline and 2, 4, 8, 12, and 16 weeks after STZ injection. Radial function was analysed using conventional M-mode, and velocity, strain and strain rate imaging. Longitudinal function was analysed using pulsed Doppler imaging of the mitral annulus.
  
  
  RESULTS
  In the diabetic rats, a significant increase in LV end diastolic and end systolic diameter was measured when compared with controls (P < 0.001). Fractional shortening and LV ejection fraction remained unchanged in both groups. Using DMI, diabetic rats demonstrated a decrease in radial systolic velocity (rate of change: +0.01 vs. -0.003 week(-1); P < 0.01) and radial systolic strain rate (+0.003 vs. -0.205 week(-1); P = 0.08) of the anteroseptal wall. Histologic examination revealed dilated cardiomyopathy with no signs of fibrosis.
  
  
  CONCLUSIONS
  Although LV ejection fraction remained preserved, velocity and strain rate imaging was able to detect radial systolic dysfunction in diabetic rats. The absence of histological signs of fibrosis suggests that other mechanisms play a role in the development of diabetic cardiomyopathy.
authors.affiliation: Department of Cardiology, In Vivo Cellular and Molecular Imaging Center, University Hospital, Brussels, Belgium. igwsc@uzbrussel.be <igwsc@uzbrussel.be>
authors.forename: Caroline
authors.initials: C
authors.lastname: Weytjens
authors.forename: Philippe R
authors.initials: PR
authors.lastname: Franken
authors.forename: Jan
authors.initials: J
authors.lastname: D'hooge
authors.forename: Steven
authors.initials: S
authors.lastname: Droogmans
authors.forename: Bernard
authors.initials: B
authors.lastname: Cosyns
authors.forename: T
authors.initials: T
authors.lastname: Lahoutte
authors.forename: Guy
authors.initials: G
authors.lastname: Van Camp
mesh_terms: D000818:Animals; D009202:Cardiomyopathies / Q000000981:diagnostic imaging / Q000209:etiology; D048909:Diabetes Complications / Q000150:complications*; D004195:Disease Models, Animal; D015150:Echocardiography, Doppler; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013599:Systole; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology