Use of quantitative two-dimensional color tissue Doppler imaging for assessment of left ventricular radial and longitudinal myocardial velocities in dogs.
OBJECTIVE
To determine left ventricular free wall (LVFW) radial and longitudinal myocardial contraction velocities in healthy dogs via quantitative 2-dimensional color tissue Doppler imaging (TDI).


METHODS
100 dogs.


METHODS
TDI was used by a single trained observer to measure radial and longitudinal myocardial movement in the LVFW. Radial myocardial velocities were recorded in segments in the endocardial and epicardial layers of the LVFW, and longitudinal velocities were recorded in segments at 3 levels (basal, middle, apical) of the LVFW.


RESULTS
LVFW velocities were higher in the endocardial layers than in the epicardial layers. Left ventricular free wall velocities were higher in the basal segments than in the middle and apical segments. Radial myocardial velocity gradients, defined as the difference between endocardial and epicardial velocities, were (mean +/- SD) 2.5 +/- 0.8 cm/s, 3.8 +/- 1.5 cm/s, and 2.3 +/- 0.9 cm/s in systole, early diastole, and late diastole, respectively. Longitudinal myocardial velocity gradients, defined as the difference between basal and apical velocities, were 5.9 +/- 2.2 cm/s, 6.9 +/- 2.5 cm/s, and 4.9 +/- 1.7 cm/s in systole, early diastole, and late diastole, respectively. A breed effect was detected for several systolic and diastolic TDI variables. In all segments, systolic velocities were independent of fractional shortening.


CONCLUSIONS
LVFW myocardial velocities decreased from the endocardium to the epicardium and from base to apex, thus revealing intramyocardial radial and longitudinal velocity gradients. These indices could enhance conventional echocardiographic analysis of left ventricular function in dogs. Breed-specific reference intervals should be defined.
Chetboul
Valerie
V
Unité de Cardiologie d'Alfort, Ecole Nationale Vétérinaire d'Alfort, 7 Avenue du Général de Gaulle, 94704 Maisons-Alfort, France.
Sampedrano
Carolina Carlos
CC
Concordet
Didier
D
Tissier
Renaud
R
Lamour
Thierry
T
Ginesta
Jacques
J
Gouni
Vassiliki
V
Nicolle
Audrey P
AP
Pouchelon
Jean-Louis
JL
Lefebvre
Hervé P
HP
D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology / Q000662:veterinary; D001835:Body Weight; D004285:Dogs / Q000502:physiology*; D005260:Female; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D012737:Sex Factors; D018615:Ultrasonography, Doppler, Color / Q000662:veterinary*; D016277:Ventricular Function, Left / Q000502:physiology*