Left ventricular myocardial velocities in healthy children:: quantitative assessment by tissue Doppler echocardiography and relation to the characteristics of filling of the left ventricle

Aim: To assess the myocardial velocities of the mitral annulus, left ventricular lateral wall, and midseptum in healthy children, and to compare these parameters with transmittal and pulmonary venous velocities. Methods and 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 transmittal 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). Conclusion: 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.