Am J Cardiol. 2008 Aug 1;102(3):363-7. Epub 2008 May 29.
Isma'eel H, Chafic AH, Rassi FE, Inati A, Koussa S, Daher R, Gharzuddin W, Alam S, Taher A.
Department of Internal Medicine Hematology-Oncology Division, American University of Beirut, Medical Center, Beirut, Lebanon.
Cardiovascular
impairment is a major cause of morbidity and mortality in patients with
thalassemia intermedia. In this study, echocardiographic assessment of
left heart condition was performed in patients with thalassemia
intermedia, and its relation to hematologic variables-amino terminal
pro-brain natriuretic peptide (NT-proBNP), ferritin, hemoglobin-and
liver iron concentration (LIC) was investigated. Echocardiographic
assessment was performed using pulse-wave Doppler and tissue Doppler
imaging. Data from 74 patients with thalassemia intermedia-35 men, 39
women, mean age 26.5 years (8 to 63) -were randomly selected and
evaluated. Blood samples were collected for NT-proBNP levels in a
random subgroup of 19 patients. Mean baseline values were hemoglobin
8.4 g/dl (4.9 to 13.1), serum ferritin 902.6 ng/ml (15 to 4,140), LIC
9.0 mg Fe/g (0.5 to 32.1), and NT-proBNP 113.5 pg/ml (16.4 to 371).
Correlation between LIC and pulmonary artery systolic pressure was
significant, suggesting that iron loading in the liver is indicative of
cardiovascular sequelae. NT-proBNP was significantly correlated with
the ratio of the left ventricular early rapid filling wave to early
diastolic velocity at the mitral annulus (r = 0.50, p = 0.04) and
hemoglobin (r = -0.49, p = 0.03), but not with other characteristics
assessed. In conclusion, this study has highlighted the importance of
using tissue Doppler imaging rather than pulse-wave Doppler to
characterize left ventricular diastolic dysfunction in patients with
thalassemia intermedia. Demonstration of the correlation of LIC and
pulmonary artery systolic pressure independent of left ventricular
filling pressures supports our hypothesis that left ventricular
diastolic dysfunction does not contribute to the increased pulmonary
artery systolic pressure in patients with thalassemia intermedia.