Relation of Left Ventricular Diastolic Dysfunction to 24-Hour Ambulatory Blood Pressure in Normotensive Predisposed Children

Background: The heart is one of the most important target organs in hypertension. Due to increased after load, concentric hypertrophy of the left ventricular myocardium develops progressively, ending in left ventricular failure. For this reason, control of hypertension should be achieved as early as possible, to avoid irreversible damage to the myocardium. Therefore, it is preferable to detect earlier changes in left ventricular function, before any structural changes occur.
Objectives: This study was performed in order to correlate the findings of ambulatory blood pressure monitoring in children who are considered normotensive by conventional blood pressure measurements but who have a predisposing factor for hypertension with left ventricular diastolic function in these children.
Methods: Left ventricular diastolic function in the form of mitral valve flow velocities was performed for 17children aged 8-13.5 years (7 boys, 10 girls) by Doppler echocardiography.
Results: All children were normotensive by conventional blood pressure measurement. However, when ambulatory blood pressure monitoring was performed, 6/17 (35%) of children were found to have elevated blood pressure loads (˃ 20% of readings ˃ 95^th percentile for age and sex). No significant differences were found between the groups regarding the early (E) or late (A) phases of mitral flow velocity. On the other hand, there was a significant difference between the group with normal blood pressure loads and the group with elevated blood pressure loads in the E/A ratio.
Conclusions: The use of ambulatory blood pressure monitoring is a useful method to evaluate children at risk for hypertension, e.g. those with recurrent UTI and those with a family history of hypertension. Early detection of target organ, e.g. heart affection in hypertension is also of great benefit, before irreversible damage occurs. The ratio of velocity of Early (E) and Late (A) phases of left ventricular filling may be a valuable marker, correlating with the presence of hypertension. In addition, this correlation would help establish the role of ambulatory blood pressure monitoring in the early identification of children at risk for ventricular dysfunction.