title: Comparison of the myocardial performance index derived by use of pulsed Doppler echocardiography and tissue Doppler imaging in dogs with volume overload.
abstract: OBJECTIVE
  To investigate the relationship between the myocardial performance index (MPI) determined by use of pulsed Doppler (PD) echocardiography and tissue Doppler imaging (TDI) in the response to volume overload-related changes in left ventricle (LV) performance.
  
  
  METHODS
  7 male Beagles.
  
  
  METHODS
  Dogs were anesthetized and intubated. A 6-F fluid-filled catheter was placed in the LV to measure LV peak systolic (LVPs) and LV end-diastolic (LVED) pressures. Preload was increased by IV infusion of lactated Ringer's solution (rate of 200 mL/kg/h for 60 minutes) into a cephalic vein. Transmitral flow velocities and aortic outflow were measured, and TDI velocities were obtained from the 4-chamber view.
  
  
  RESULTS
  Acute volume overload induced a significant increase in heart rate, LVPs pressure, and LVED pressure, compared with baseline values. A significant decrease in the PD-MPI and TDI-MPI values and a significant correlation (r = 0.70) between PD-MPI and TDI-MPI were detected. The PD-derived A-wave velocity, ejection time, and isovolumic relaxation time (IRT) and the TDI-derived IRT, MPI, and ratio of the velocity of the E wave to the velocity of the ventricular portion of the E wave during early diastole had equal ability to predict LVED pressure (r(2) = 0.63).
  
  
  CONCLUSIONS
  The TDI-MPI was closely correlated with LV filling pressure and may be helpful in evaluating global cardiac function in dogs.
authors.affiliation: Department of Small Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, 23-35-1 Higashi, Towada, Aomori 034-8628, Japan.
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Hori
authors.forename: Shoh-Ichi
authors.initials: S
authors.lastname: Kunihiro
authors.forename: Fumio
authors.initials: F
authors.lastname: Hoshi
authors.forename: Sei-Ichi
authors.initials: S
authors.lastname: Higuchi
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000662:veterinary; D002306:Cardiac Volume; D004283:Dog Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging*; D004285:Dogs; D018619:Echocardiography, Doppler, Pulsed / Q000662:veterinary*; D006339:Heart Rate / Q000502:physiology; D008297:Male; D012044:Regression Analysis; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*