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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Left ventricular performance was studied in 23 young patients with severe chronic anemia due to beta-thalassemia major and intermedia. The patients were divided into three groups according to the number of blood transfusions they had received. The left ventricle (LV) was enlarged in patients who had not received blood and larger still in patients who had received multiple transfusions. Echocardiography and systolic time interval measurements showed that systolic function of the LV was good in all the patients and that there was no statistical difference in systolic function in patients who had and those who had not received multiple transfusions. Heart rate was increased in the latter group. Stroke index and cardiac index were high, especially in patients in Group 3. The diastolic closure rate (EF slope) of the anterior mitral leaflet and its amplitude of movement were increased, but less so in Group 3; this may reflect an alteration in diastolic LV distensibility. The results indicate that despite the presence of cardiomegaly and severe clinical congestive heart failure, LV performance is well preserved in patients with beta-thalassemia, even in those who have received repeated blood transfusions. Clinical cardiac failure is the consequence of volume overload and abnormal chamber compliance. There was no evidence in this of a congestive cardiomyopathy.
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PMID:Left ventricular function in beta-thalassemia and the effect of multiple transfusions. 16 23

25-yr old female identical twins of Italian-American origin concordant for sickle beta-thalassemia were studied to explain their clinical differences. One of them has been severely affected from childhood with one aplastic crisis, an earlier onset of vaso-occlusive crises, and recent cardiac decompensation; the other twin shows no cardiac decompensation. Similar are their degree of anemia, RBC indices, blood volumes, absence of splenic sequestration, depression of pO2, elevation of p50 and 2,3-DPG, hemoglobin composition, and peripheral blood globin-synthetic rates. Regarding differences, the more severely affected has a shorter 51Cr RBC life span, a greater menstrual blood loss, and is more overweight, whereas the less severely affected has functional asplenia by 99mTc scanning and a larger proportion of RBC with decreased cellular deformability. We conclude that in sickle beta-thalassemia: (1) genotype alone does not determine the clinical course; (2) significant differences in clinical course can occur with almost identical hemoglobin composition and globin synthetic rates; (3) cellular deformability changes do not correlate exactly with clinical course; and (4) functional asplenia and leanness may be advantageous.
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PMID:Sickle beta-thalassemia: identical twins differing in severity implicate nongenetic factors influencing course. 98 45

Congestive heart failure is the most common cause of death in young adults with thalassaemia major. In the present study we compared atrial natriuretic peptide levels (ANP) in 30 asymptomatic patients with thalassaemia major (aged 16.6 +/- 6.4 years), normal left ventricular diastolic cavity dimension and systolic function, with 30 aged and sex matched normal control subjects. ANP levels were significantly higher in patients with thalassaemia major compared to controls (93.9 +/- 26.3 pg.ml-1 vs 51.8 +/- 26.5 pg.ml-1; P < 0.001). Plasmatic renin activity, aldosterone, urinary sodium and catecholamine levels at basal conditions did not differ significantly in these two groups (ns). Blood volume stimulation (blood transfusion) in thalassaemic patients was followed by an increase of mean ANP values (93.9 +/- 26.3 to 109.1 +/- 40.5 pg.ml-1; P < 0.03). ANP basal levels above two standard deviations of the mean values obtained in normal control subjects were considered as abnormal and found to be in close correlation with the presence of diastolic dysfunction of the left ventricle identified by Doppler echocardiography. The method has a 57% sensitivity and a 91% specificity for revealing pre-clinical cardiac involvement (P < 0.02). Although a longer observation period is necessary in order to define the clinical and prognostic significance of these data, our results show that an increase in ANP basal values is present in asymptomatic patients with thalassaemia major. This suggests initial myocardial involvement, while ANP response to volume overload is maintained.
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PMID:Cardiac involvement in thalassaemia major: altered atrial natriuretic peptide levels in asymptomatic patients. 139 10

Thalassemia patients succumb at a young age to congestive heart failure. Hitherto, attention has been focused on left ventricular function. This report emphasizes right ventricular dysfunction and abnormal pulmonary function. We performed cardiopulmonary evaluation, including echo-Doppler, spirometry, CO diffusion (DCO), and blood gas analyses in 35 patients with homozygous beta-thalassemia maintained by multiple blood transfusions. Six autopsy lung specimens were studied. Thalassemia patients exhibited pulmonary dysfunction, characterized by hypoxemia (85 percent of the patients were outside the 95 percent confidence limits), reduced lung volumes (51 percent), flow rates (63 percent) and DCO (50 percent). Right ventricular dysfunction was more prevalent than left ventricular dysfunction. Furthermore, 75 percent of the patients had evidence of pulmonary hypertension consistent with more frequent right ventricular rather than left ventricular dysfunction. Our findings suggest that in thalassemia patients, complex cardiopulmonary abnormalities precede the final outcome of congestive heart failure.
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PMID:Cardiopulmonary assessment in beta-thalassemia major. 222 58

Clinical and hemodynamic studies were conducted in 6 women and 2 men with beta-thalassemia/hemoglobin E disease. All except one had splenectomy. The patients were hospitalized in the state of congestive heart failure. The systemic blood pressure was low or normal. The electrocardiograms revealed normal sinus rhythm in all, right axis deviation in some, right atrial enlargement in the majority and repolarization abnormalities in some. The echocardiograms were sensitive to detect the right heart abnormalities and pericardial effusion. Cardiac catheterization disclosed moderate to marked hypoxemia. All patients except one had pulmonary hypertension. Some had left ventricular dysfunction. From this study. It is concluded that right heart involvement secondary to diffuse pulmonary thromboembolic disease is a major complication of beta-thalassemia/hemoglobin E disease.
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PMID:Cardiac involvement in beta-thalassemia/hemoglobin E disease: clinical and hemodynamic findings. 223 94

Cardiac dysfunction is the most common cause of death in patients with homozygous beta-thalassemia. We studied a group of 10 older patients (mean age 17.5 years) with and without preexisting cardiac dysfunction who had begun chelation therapy on the average of 10 years after regular transfusions were initiated. Over the 4-year study period, two patients were noncompliant with deferoxamine therapy. Their clinical status and cardiac function deteriorated, and both died with evidence of arrhythmia and congestive heart failure. The remaining eight patients were compliant. Despite a drop in mean serum ferritin from 3,814 +/- 577 (SE) ng/ml to 1,056 +/- 146 ng/ml (p less than 0.01), two patients with preexisting cardiac problems and one patient without preexisting heart disease developed further abnormalities. Of the three patients whose status declined, one ultimately improved with alternative chelation therapy. These data suggest that for a few older patients, improvement or stabilization of cardiac status may not be achieved with improved compliance and reduced serum ferritin levels. For these patients, new approaches appear to be warranted. On the other hand, we have demonstrated that in most cases, older patients who began chelation therapy years after transfusions began have benefited from compliance with standard subcutaneous deferoxamine regimens.
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PMID:Chelation therapy and cardiac status in older patients with thalassemia major. 230 80

The left ventricular dimension and posterior wall dynamics were studied by computer assisted analysis of M mode echocardiography in 25 normal children (group 1) and 32 transfusion dependent children with beta thalassaemia major who had no evidence of heart failure (group 2). Twenty seven of those in group 2 remained well but five died of cardiac decompensation within 12 months. Compared with group 1, the left ventricular fractional shortening and ejection fraction were normal in those in group 2 who survived but diminished in those who died. Evaluation of left ventricular dimension and posterior wall dynamics during systole (peak shortening rate, peak velocity of circumferential fibre shortening, and peak posterior wall thickening rate) showed similar findings in that only the group who died had abnormal values. The left ventricular dimension and posterior wall diastolic dynamics (peak relaxation rate, normalised peak relaxation, peak wall thinning, and normalised peak wall thinning rate), however, showed progressively slower rates in all the children in group 2. The findings suggest that left ventricular diastolic dysfunction occurs early in myocardial impairment in patients with beta thalassaemia major. When there are abnormalities in both diastole and systole, the myocardial impairment is advanced and the prognosis is poor.
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PMID:Left ventricular function in beta thalassaemia major. 262 27

Doppler shift blood flow velocity-time waveforms in the umbilical arteries (UA), aorta (A), and inferior vena cava (IVC) in eight fetuses with alpha-thalassemia (alpha-thal) hydrops fetalis were described. The UA waveforms in these fetuses with anemia in utero depicted a hyperdynamic circulatory state with a relative increase in acceleration slope, more linear decline from maximum systole to end diastole, and reduced spectral broadening. The aortic waveforms similarly displayed distorted systolic peaks, flow turbulence, and greatly elevated diastolic frequencies. Reversal of end diastolic flow in the IVC also indicated cardiac decompensation in these fetuses. Progressive changes in these waveforms were apparent in two fetuses that had serial evaluation. In another four fetuses in which alpha-thal major was diagnosed in the second trimester by DNA analysis and had Doppler evaluation before termination of pregnancy, consistent changes in the UA, A, and IVC waveforms were not observed. This study confirms the potential usefulness of Doppler spectral waveforms in depicting altered hemodynamic changes in the fetus and in the evaluation of hydrops fetalis. Doppler ultrasound examination can be included as part of the routine workup of hydrops fetalis.
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PMID:Doppler blood flow velocity waveforms in alpha-thalassemia hydrops fetalis. 332 49

In patients with iron overload associated with severe, transfusion-dependent beta-thalassemia, congestive heart failure develops during the second decade of life. Biventricular heart function was studied by multigated radionuclide angiography in 22 patients with beta-thalassemia major. Six patients were symptomatic. Congestive heart failure developed in five patients at the time of blood transfusions, and one other patient had been treated for multiple ventricular extrasystole. The mean (+/- SD) left ventricular ejection fraction was normal (63.0% +/- 7.6%). Only one patient had a left ventricular ejection fraction under the normal level (less than 50%). The mean (+/- SD) right ventricular fraction (RVEF) was 33.3% +/- 9.4%. In only three patients was the RVEF normal (greater than or equal to 40%); an RVEF under 30% was registered in six patients. We suggest that the early right ventricular dysfunction in patients with beta-thalassemia may be due to pulmonary hypertension secondary to iron overload and iron deposits in the ventricles.
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PMID:Right ventricular cardiac dysfunction in beta-thalassemia major. 378 90

The systolic and diastolic left ventricular (LV) function was studied by M-mode echocardiography in 60 patients with beta-thalassemia (mean age +/- SD, 17.1 +/- 7.5 years) and 30 healthy controls (15.4 +/- 3.8 years). In thalassemic patients, echocardiograms were obtained 48 h posttransfusion, with a mean hemoglobin level of 12.4 +/- 0.9 g/dl. To examination time, thalassemic patients had received 30-774 blood units (318 +/- 176). Congestive heart failure (CHF) was present in 14 thalassemic patients (19.6 +/- 3.4 years), while 46 (16.3 +/- 8.2 years) had no clinical signs of CHF. Global LV function study showed enlarged LV dimensions in thalassemic patients with CHF (p less than 0.001) and similar cavity size in controls and patients without CHF (p = NS). The same was true for velocity measurements, while diastolic LV indices had similar values in all groups (p = NS). Segmental LV function study showed no significant differences in systolic and diastolic LV posterior wall behavior between thalassemic patients and controls, and even more, between thalassemic patients with and without CHF, while it was independent of iron load. These findings indicate that global and segmental LV function in thalassemic patients remain within normal limits until the final stages of the disease. CHF onset marks the deterioration of LV systolic performance, while global and segmental diastolic indices do not change significantly. The above findings question the role of iron overload in the development of CHF in beta-thalassemia.
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PMID:Global and segmental left ventricular function in beta-thalassemia. 399 17


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