Abstract 546: Optimal Combined Chelation Therapy Does Not Improve Left Ventricular Diastolic Function in Adult β-Thalassaemia Major Patients
Purpose: Combined chelation therapy (deferiprone plus deferoxamine), compared with deferoxamine monotherapy, is known to improve cardiac hemochromatosis and left ventricular (LV) systolic function, in b-thalassaemia major patients (b-thal). This study was conducted to evaluate the effect of optimal combined chelation therapy in diastolic LV function in adult b-thal.
Method: Twenty six b-thal (Group C) and 35 b-thal (Group D) older than 30 years (mean age C: 37.7±5.7 vs D:35.8±5.9 years, p:ns) were included in the study and underwent a thorough echocardiographic study 4 –10 days from last transfusion. Group C were on optimal combined chelation therapy and group D on monotherapy with deferoxamine for the last 2 years. Simpson rule was used for LV volumes calculation and LV ejection fraction estimation. Mitral inflow E and A velocities were recorded and E wave deceleration time (DT) was measured. Using tissue Doppler, S′ (systolic), E′ (early diastolic) and A′ (late diastolic) velocities of the mitral annulus were recorded at the interventricular septum (ivs)and lateral LV wall (lat). E/E′ivs and E/E′lat ratios were calculated as the most reliable indexes of LV diastolic function.
Result: Group C patients presented with better MRI cardiac T2* values (C: 34.9±4.6 vs D: 23.5±7.3, P<0.001). LV end systolic volume and LV ejection fraction was also improved in group C (LVSV: C:38±12 vs D: 46±16 ml, p<0.05, LVEF: C: 62±4 vs D: 58±8, p±0.05). Mitral E and A wave, mitral annulus E′ivs and E′lat were similar in the 2 groups. S′ivs (C: 7.9±1.2 vs D: 5.5±2.0 cm/sec, p:0.01) and DT (C:175±33 vs D:154±22 msec, p<0.05)were only increased in group C. There was not any difference in E/E′ivs (C:10.6±3.1 vs D:12.1±4.3, p:ns) and E/E′lat (C: 7.9±3.2 vs D:9.0±3.1, p:ns) ratios.
Conclusion: Optimal combined chelation therapy seems not to improve LV diastolic function in the same degree as iron load and systolic function, in adult b-thalassaemia major patient population.