RESUMEN
The aim of the present work is to demonstrate the value of Tissue Doppler Imaging [TDI] compared to Conventional Color Doppler Echocardiography in detection of early cardiovascular changes in untreated versus adequately treated patients with Congenital Hypothyroidism [CH]. This study included forty patients with CH selected from regular attendants following up in the Pediatric Endocrinology clinic, Children's Hospital, Ain-Shams University. Cardio logical assessment was done in the Cardiology department, Ain Shams University Hospitals. The patients were divided into two groups: Group A [adequately treated patients] included 20 patients [10 males and 10 females, mean age = 7.1 +/- 5.6 years] and Group B [untreated patients] included 20 patients [10 males and 10 females, mean age = 8.23 +/- 5.7 years] who were studied before starting L-Thyroxine replacement therapy [Eltroxin]. Patients were compared to thirty [15 males and 15 females, mean age = 7.26 +/- 5.4 years] apparently normal age and sex matched controls. Patients and controls were subjected to the following : Full his- tory taking , thorough physical examination, bone age assessment , estimation of Free Thyroxine [FT4] and thyroid stimulating hormone [TSH] initially at diagnosis [before starting L-Thyroxine replacement therapy] then periodically , standard twelve lead Electrocardiogram [ECG], Conventional Color Doppler Echocardiography and TDI. The results revealed a statistically highly significant difference [p <0.001] between the two patient groups [A and B] as regards height, serum levels of TSH and FT4 and a statistically non-significant difference [p>0.05] as regards R-wave amplitude at V1, V6 [x2 =1.17] and QRS-wave duration at V6 [x2 =0.931]. Conventional Echocardiography revealed mild pericardial effusion in ten patients [4 in group A and 6 in-group B], normal systolic and diastolic indices, and right and left sided chamber dimensions and none of the patients had congenital heart defects. There is a statistically significant difference [p<0.05] between the two groups of patients as regards mitral valve thickening [x2 =3.8], aortic valve thickening [x2=5.23] and mitral regurgitation [x2 =6.27]. TDI results of group A [adequately treated patients] versus the control group revealed a statistically significant [p<0.05] difference as regards septal mitral annular A- velocity and anterior tricuspid annular E-velocity while there was a statistically non significant difference [p>0.05] between them as regards all other TDI values denoting diastolic affection only .TDI results of group B [untreated patients] versus the control group revealed a statistically highly significant difference p<0.001] at the anterior mitral annular A- velocity , anterior tricuspid annular E-velocity and S-velocity and a statistically significant difference [p<0.05] at the inferior mitral annular A-velocity , at the septal and inferior mitral annular S velocity , tricuspid annular average E-velocity and S-velocity denoting systolic and diastolic affection. In conclusion the results of the present study demonstrated the value of TDI in assessment of patients with CH for detection of early cardiovascular changes that were undetected by Conventional Color Doppler Echocardiography. The absence of systolic impairment by TDI in group A [adequately treated patients] versus group B [untreated patients] indicates that adequate treatment with L-Thyroxine replacement therapy [Eltroxin] prevents such impairment and elucidates the importance of adequate replacement therapy [Eltroxin] in prevention of some cardiac complications of CH