The Effect of L-Arginine Oral Supplementation on the Improvement of Cardiovascular Function and Pulmonary Artery Pressure in Patients with Major and Intermedia β-Thalassemia

BACKGROUND: Thalassemia is the most common inherited anemia in worldwide. Heart failure is the most common cause of mortality and morbidity in patients with major and intermedia β-thalassemia. This study aimed to evaluate the effect of oral administration of L-arginine on the improvement of systolic Pulmonary Artery Pressure (PAP) and cardiac function in patients with major and intermedia β-thalassemia. METHODS: This randomized clinical trial was done on 88 patients with β-thalassemia admitted to Ali Asghar Hospital, Tehran, Iran between 2020 and 2021. Echocardiography was performed for all the patients before the intervention. Afterwards, the patients were randomly divided into two groups of placebo and L-arginine. The patients underwent echocardiography after eight weeks and were compared with respect to the results. RESULTS: The mean blood transfusion interval was 20.21 d in the placebo group and 17.14 d in the L-arginine group (P=0.082). The results revealed no significant difference between the two groups regarding the mean levels of Hemoglobin (Hb) and ferritin, frequency of splenectomy. However, the mean PAP significantly decreased from 32.88 to 26.02 in the L-arginine group (P=0.009), but did not change in the placebo group. Nonetheless, no significant change was observed in the mean Ejection Fraction (EF) before and after L-arginine administration. CONCLUSION: L-arginine administration prevented the increase of PAP and was effective in preventing cardiovascular disorders including increased systolic PAP in patients with major and intermedia B-thalassemia. However, the results have to be confirmed in further studies with larger sample sizes.