Doppler-defined pulmonary hypertension in β-thalassemia major in Kurdistan, Iraq

Abstract

Cardiopulmonary complications are among the most important complications of thalassemia major. Pulmonary hypertension is among these complications and studies addressing its frequency and associations in the latter disorder are sparse from Iraq. For this purpose a total 100 thalassemia major patients (≥ 8 years old) were enrolled from a main thalassemia center in Kurdistan, Northern Iraq. All patients had a full history and clinical examination. Full blood count, biochemical tests and viral screen including hepatitis B surface antigen and hepatitis C virus antibody, in addition to transthoracic Doppler echocardiography for tricuspid regurgitation jet velocity (TRV). The enrolled patients had a mean (SD) age of 17.6 (5.5) years, and included 52 males and 48 females. Pulmonary hypertension as defined by TRV> 2.8 m/s coupled with both exertional dyspnea and an absence of left sided heart failure, was identified in nine patients (9%). The latter subgroup of patients had significantly higher reticulocyte counts, S. LDH, S. ferritin, and hepatitis C sero-positivity compared to those without this complication by univariate analysis. While by multivariate logistic regression only reticulocytes and hepatitis C sero-positivity remained significant. Furthermore, TRV as a continuous variable was positively correlated with reticulocytes, S. bilirubin and LDH (p<0.001, p = 0.002 and p<0.001 respectively), but not with age or S. ferritin (p = 0.77, and p = 0.93 respectively). In conclusion, pulmonary hypertension is not uncommon in Iraqi patients with thalassemia major, and it appears to be linked to chronic hemolysis rather than iron overload.