Comparison of the myocardial performance index derived by use of pulsed Doppler echocardiography and tissue Doppler imaging in dogs with volume overload.
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.
Hori
Yasutomo
Y
Department of Small Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, 23-35-1 Higashi, Towada, Aomori 034-8628, Japan.
Kunihiro
Shoh-Ichi
S
Hoshi
Fumio
F
Higuchi
Sei-Ichi
S
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*