Related Experiment Videos
Doppler evaluation of left ventricular diastolic filling in children with systemic hypertension
Insights
Children with systemic hypertension show impaired diastolic function, indicated by altered atrial contraction velocity and filling patterns. These findings highlight the impact of hypertension on pediatric cardiac health.
Area of Science:
- Pediatric Cardiology
- Cardiovascular Physiology
- Echocardiography
Background:
- Systemic hypertension in children can affect cardiac function.
- Left ventricular (LV) diastolic function is crucial for maintaining cardiac output.
- Assessing diastolic function in pediatric hypertension is important for early detection of complications.
Purpose of the Study:
- To evaluate left ventricular (LV) diastolic function in children diagnosed with systemic hypertension.
- To compare diastolic parameters between hypertensive children and healthy controls using echocardiography and Doppler methods.
Main Methods:
- M-mode echocardiography and pulsed Doppler examination of LV inflow were performed on 11 hypertensive children and 7 normal children.
- Measurements included echocardiographic diastolic time intervals and Doppler-derived velocities (E and A waves) and areas under the Doppler curve.
- Specific parameters analyzed were A velocity, E/A ratio, and various diastolic filling time intervals and areas.
Main Results:
- Hypertensive children exhibited significantly higher A velocity (atrial contraction wave) compared to normal subjects.
- The proportion of early diastolic filling (0.33 area/total area) was significantly lower in hypertensive children.
- A area and A area/total area were also significantly different between the groups, indicating altered diastolic filling patterns.
Conclusions:
- Children with systemic hypertension demonstrate impaired left ventricular diastolic function.
- Altered atrial contraction velocity and filling patterns are key indicators of diastolic dysfunction in pediatric hypertension.
- Echocardiography and Doppler assessment are valuable tools for detecting diastolic abnormalities in hypertensive children.
Abstract:
To assess left ventricular (LV) diastolic function in children with systemic hypertension, 11 patients with hypertension (mean blood pressure 99 mm Hg) and 7 normal patients (mean blood pressure 78 mm Hg) underwent M-mode echocardiography and pulsed Doppler examination of the LV inflow. From a digitized trace of the LV endocardium and a simultaneous phonocardiogram, echocardiographic diastolic time intervals, peak rate of increase in LV dimension (dD/dt), and dD/dt normalized for LV end-diastolic dimension (dD/dt/D) were measured. Doppler diastolic time intervals, peak velocities at rapid filling (E velocity) and atrial contraction (A velocity), and the ratio of E and A velocities were measured. The following areas under the Doppler curve and their percent of the total area were determined: first 33% of diastole (0.33 area), first 50% of diastole, triangle under the A velocity (A area), and the triangle under the E velocity (E area). The A velocity (patients with hypertension = 0.68 +/- 0.11 m/s, normal subjects = 0.49 +/- 0.08 m/s), the 0.33 area/total area (patients with hypertension = 0.49 +/- 0.09, normal subjects = 0.58 +/- 0.08), the A area (patients with hypertension = 0.17 +/- 0.05, normal subjects = 0.12 +/- 0.03), and the A area/total area (patients with hypertension = 0.30 +/- 0.11, normal subjects = 0.20 +/- 0.07) were significantly different between groups (p less than 0.05). M-mode and Doppler time intervals, (dD/dt)/D, E velocity, and the remaining Doppler areas were not significantly different between groups.(ABSTRACT TRUNCATED AT 250 WORDS)