Relation between iron-overload indices, cardiac echo-Doppler, and biochemical markers in thalassemia intermedia.
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.
Isma'eel
Hussain
H
Department of Internal Medicine Hematology-Oncology Division, American University of Beirut, Medical Center, Beirut, Lebanon.
Chafic
Abdul Hamid El
AH
El Rassi
Fuad
F
Inati
Adlette
A
Koussa
Susan
S
Daher
Rose
R
Gharzuddin
Walid
W
Alam
Samir
S
Taher
Ali
A
D000293:Adolescent; D000328:Adult; D001794:Blood Pressure; D002648:Child; D015150:Echocardiography, Doppler; D005260:Female; D005293:Ferritins / Q000097:blood; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007501:Iron / Q000032:analysis; D019190:Iron Overload; D008099:Liver / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011651:Pulmonary Artery; D013789:Thalassemia / Q000097:blood* / Q000503:physiopathology*; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology
D006454:Hemoglobins; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D005293:Ferritins; D007501:Iron