Left Ventricular Diastolic Dysfunction in Congenital Chronic Anaemias During Childhood as determined by Comprehensive Echocardiographic Imaging including Acoustic Quantification

Abstract

To evaluate prospectively the left ventricular performance in thalassaemia major and sickle cell disease using comprehensive echocardiographic imaging including acoustic quantification during early childhood. Twenty-three patients with thalassaemia and 26 patients with sickle cell disease underwent echocardiographic examination including M-mode, 2-D, Doppler and acoustic quantification. All patients were matched for age, sex, weight and height with 20 normal controls. All patients were below 13 years of age. Thalassaemia and sickle cell disease patients were significantly anaemic when compared with normals (P<0.0001). All patients had normal left ventricular systolic parameters. Acoustic quantification-derived left ventricular volumes, filling rates, and emptying rates were not different in thalassaemia patients from controls. Left ventricular volumes, however, were larger in sickle cell disease patients than in controls. In contrast, by Doppler technique, left ventricular filling occurs mainly in early diastole (E wave) in thalassaemia patients and mainly in late diastole (A wave) in sickle cell disease patients, (P=0.03 and 0.01 respectively). E/A ratio was lower and diastolic filling period was shorter than normal in sickle cell disease but not in thalassaemia patients. Patients in both groups had left ventricular mass (determined by M-mode) significantly higher than normal (P<0.0001). The left ventricular systolic performance is well preserved in patients with chronic anaemia due to thalassaemia major and sickle cell disease during early childhood. In both diseases, however, there is left ventricular hypertrophy and measurable abnormalities in the diastolic filling detected by Doppler. Such changes do not fit a specific cardiomyopathic pattern due to diastolic dysfunction i.e. restrictive physiology vs delayed relaxation. Acoustic quantification of left ventricular diastolic parameters (filling rates) was less sensitive than Doppler in detecting these early diastolic abnormalities in both diseases.