Doppler Echocardiographic Evaluation of Left Ventricular Function in Children with Dilated Cardiomyopathy

Thirty-one children with dilated cardiomyopathy (DCM), subdivided into two groups, were evaluated by 2-D, M-mode and pulsed wave Doppler echocardiography. Group I consisted of 20 patients (age 4.4±3.67 years) with ongoing symptoms, radiological findings and echographic evidence of DCM according to 2-dimensional (spherical shape) and standard M-mode criteria: left ventricular dimension (LVDd), shortening fraction (SF) and mitral-septal-separation (MSS). Group II consisted of 11 DCM patients (age 4.3±2.64 years) who initially met similar criteria as Group 1 patients. but, after a follow-up and treatment period of 1.5 to 3.5 years, the clinical, radiological and echocardiographic findings (left ventricular configuration, dimension, SF and MSS) of these eleven patients had retumed to normal at the time of this investigation. Careful measurements were taken from the flowvelocity curve of the ascending aorta: Maximal velocity (Vmax), velocity-time integral (VTI), accceleration, acceleration time (AT) and LV ejection time (LVET). The ratio of acceleration time to LV ejection time (AT/LVET) was calculated. The results were compared with those from 24 healthy children (age 6.5±3.2 years) The values of Vmax, VTI, acceleration and AT/LVET for healthy children were 1.30±0.21 m/s, 22.9±4.26 cm, 22.0±5.14 m/s/s and 0.23±0.05, respectively. Vmax, VTI and acceleration were significantly depressed and AT/LVET was increased in Group I patients (p<0.001). Furthermore, VTI, acceleration and especially AT/LVET could also differentiate the "normalised" patients of Group II from the two other groups, signifying the presence of some underlying defect in systolic function although standard M-mode criteria were found normal in these children. We concluded that these Doppler parameters of systolic ventricular function should be used during long-term follow-up of patients with dilated cardiomyopathy to decide whether or not systolic left ventricular function is completely normalised.