Right Ventricular Diastolic Function in Patients with Thalassemia Major

Abstract

Dear Editor, We read with great interest the article Echocardiography in Thalassemic Patients on Blood Transfusions and Chelation without Heart Failure written by Rodrigues et al1. They aimed to evaluate cardiac structure and function by conventional Doppler echocardiography and tissue Doppler imaging in patients with thalassemia major (TM) and no clinical evidence of heart failure. They found that left atrium volume index, mitral septal E/Em ratio and duration of reverse pulmonary vein flow were significantly higher in TM than in anemia and healthy groups. However, no differences were found in left and right ventricular structures and systolic function indexes between the groups. We believe that these findings will act as a guide for further studies regarding echocardiographic evaluation of left and right ventricular functions in patients with TM. Contrary to common belief, the right ventricle is not a passive chamber. A large number of acute and chronic diseases have been associated with RV diastolic dysfunction, including both pressure and volume overload pathologies such as primary lung disease, congenital heart disease, cardiomyopathies, ischemic heart disease, systemic diseases2,3. Only a few studies assessed the RV diastolic function. In those studies, the RV diastolic function has been evaluated using Doppler velocities of the transtricuspid flow (E, A, and E/A), tissue Doppler velocities of the tricuspid annulus (E', A', E'/A'), deceleration time, and IVRT. Most commonly used in recent studies are the tricuspid E/E' ratio, RA area or volume, and diastolic strain rate. A good correlation was shown between the tricuspid E/E' ratio and RA volume, and hemodynamic parameters. An E/E' ratio ≥4 had high sensitivity and specificity for predicting RA pressure ≥10 mm Hg in non-cardiac surgery intensive care unit patients4. The current study1 did not evaluate RV diastolic function and RA volume. Further studies should be conducted to assess RA volume and RV tissue Doppler diastolic parameters such as tricuspid E/E' ratio.