Left ventricular myocardial velocities in healthy children: quantitative assessment by tissue Doppler echocardiography and relation to the characteristics of filling of the left ventricle.
OBJECTIVE
To assess the myocardial velocities of the mitral annulus, left ventricular lateral wall, and midseptum in healthy children, and to compare these parameters with transmitral and pulmonary venous velocities.


RESULTS
We examined 72 children, half being male, who had no systemic or cardiac pathologies. Their mean age was 6.73 +/- 5.10 years, with a range from 0.1 to 17.75 years, and a median age of 6.71 years. Each parameter was measured twice, at end inspiration and end expiration. The tissue velocities are similar in males and females (p > 0.05). The longitudinal velocity of the heart in early diastole has a positive correlation with age (p < 0.05; midseptum velocity r = 0.57, left ventricular lateral wall velocity r = 0.56, mitral annulus velocity r = 0.56), and the tissue velocities are not influenced by respiration (p > 0.05). The myocardial velocities of different segments of the left ventricle are not correlated with the transmitral or pulmonary venous flows (p < 0.05). When age is controlled for heart rate, age mainly affects the systolic velocity of the mitral annulus and the early diastolic velocity of the midseptum in longitudinal axis, as well as the early diastolic velocity of the midseptum in transverse axis (p > 0.05 for all, r = 0.34, 0.29, 0.30 respectively).


CONCLUSIONS
This study, which has determined reference values for tissue velocities in a large healthy group of children, will now set the scene for further studies in children with heart disease.
Ayabakan
Canan
C
Department of Pediatric Cardiology, Hacettepe University, Ankara, Turkey. cayabakan@yahoo.com
Ozkutlu
Süheyla
S
D000293:Adolescent; D000367:Age Factors; D001783:Blood Flow Velocity / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015150:Echocardiography, Doppler; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology; D012016:Reference Values; D013318:Stroke Volume; D016276:Ventricular Function; D016277:Ventricular Function, Left / Q000502:physiology*