[Left ventricular mass index and diastolic function in children with thalassemia major]

ABSTRACT

Cardiac complications are the major cause of morbidity and mortality in patients with Beta Thalassemia Major [BTM]. Increased left ventricular mass index is due to ventricular hypertrophy after iron overload. The purpose of this study was to assess the relationship between left ventricular mass index [LVMI] and diastolic function and early diagnosis of cardiac involvement by echocardiography. This cross-sectional study was conducted on 44 patients with BMT and a healthy control group [matched based on age and sex] in Ali-Asghar hospital of Zahedan from September 2002 to December 2003. After physical examination, complete M-Mode, 2D and Doppler echocardiography studies were performed and left ventricular diastolic and left ventricular mass index were assessed and these data were compared with those of the control group. From 44 patients 24 were male. The mean age was 14.3+2.9 years. The mean weight, height and body surface area [BSA] were 34.5 +/- 7.4, 142.2 +/- 12.3, 1.16 +/- 0.17 respectively. Compared to the control group, the mean weight, height and BSA in cases were decreased, the mean heart rate increased and systolic and diastolic blood pressures decreased significantly. LVMI increased significantly [50% compared with that of the control group] too. Cardiac output stroke volume and also heart rate increased significantly due to increased left chamber size. Systolic function was in acceptable range in all subjects excluding 5 patients. Diastolic dysfunction was more common and isovolumic relaxation time [IVRT] was the most frequent abnormal diastolic index which increased significantly with increment of LVMI. The results of this study showed that prolonged IVRT and LVMI had a significant correlation. Therefore the assessment of LVMI and diastolic function is a must that leads to early diagnosis of cardiac dysfunction