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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Splenomegaly is common in beta-thalassemia, bearing some particular hemodynamic features, while splenectomy is an established therapeutic intervention in these patients. Their effects, however, on systemic hemodynamics and thalassemia heart disease have not yet been assessed. The study included 32 consecutive patients, 13 with thalassemia major (TM) and 19 with thalassemia intermedia (TI), aged 23.4+/-4.2 years, requiring splenectomy. Assessment was performed before and 6 months after splenectomy and included hematological profile and resting echocardiography; total blood volume was also measured in 10 of 32 cases. Preoperative echocardiographic data were compared with those of 34 controls. Preoperative left ventricular diameters and mass, cardiac index, and systolic pulmonary artery pressure were all significantly higher in patients compared to controls (p<0.001), but did not differ significantly between TM and TI patients. Postoperatively, the mean hemoglobin level increased from 8.1+/-0.6 to 9.1+/-0.4 g/dl (p<0.001), total blood volume index declined from 2847+/-332 to 2310+/-276 ml/m(2) (p<0.001), blood transfusions were discontinued in 80% of TI patients and mean 6-monthly transfusion requirements in TM patients were reduced from 28+/-5 to 22+/-4 units (p<0.001). However, cardiac parameters were not significantly modified. It seems that left ventricular remodeling, high output state, and increased pulmonary artery pressure characterize both TM and TI patients who require splenectomy. Although these abnormalities remain unchanged after splenectomy, the removal of the spleen may contribute to the prevention of further cardiac damage by ameliorating the patients' hematological status and reducing their transfusion needs.
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PMID:Cardiovascular effects of splenomegaly and splenectomy in beta-thalassemia. 1571 2

"Hair-on-end" skull changes resembling thalassemia were rarely described in the 1950s and 1960s in children with cyanotic congenital heart diseases; these changes were described almost entirely in patients with tetralogy of Fallot or D-transposition of the great arteries. As these lesions have become correctable, the osseous changes, never common, seem now only to exist in a small number of patients with uncorrectable complex cyanotic congenital heart disease who survive in a chronic hypoxic state. We present two cases: a case of marked marrow expansion in the skull of a 5-year-old boy with uncorrectable cyanotic heart disease studied by CT, and a second case of an 8-year-old with tetralogy of Fallot and pulmonary atresia studied by plain skull radiographs. The true incidence of these findings is unknown.
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PMID:'Hair-on-end' skull changes resembling thalassemia caused by marrow expansion in uncorrected complex cyanotic heart disease. 1577 29

Cambodia is an extremely underdeveloped country in Southeast Asia with a childhood mortality rate of 105/1000 live births. Angkor Hospital for Children is a paediatric teaching hospital in Siem Reap, northwest Cambodia, which serves as the provincial paediatric department but also sees children from provinces throughout northern Cambodia, and with training provided for health workers from all parts of the country. The impact of genetic disease on this paediatric population is discussed, addressing the areas of haematology (including thalassaemia and other haemoglobinopathies, glucose-6-phosphate deficiency and bleeding disorders), multifactorial disorders (cleft palate, congenital heart disease and neural tube defects), and uncommon genetic disorders and chromosomal syndromes. In the future, as low-income countries develop and their burden of infectious disease begins to subside, the contribution of these disorders to paediatric morbidity and mortality will become increasingly apparent. This transition needs to be considered in the allocation of health resources and in the structuring of undergraduate and postgraduate medical education.
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PMID:Genetic disorders in a paediatric hospital in Cambodia. 1609 16

Historically, fractures are cited as a frequent problem in patients with Thalassemia prior to optimization of transfusion and chelation regimens. The aim of this study was to determine the prevalence of fractures in a contemporary sample of North American patients with Thalassemia. The North American Thalassemia Clinical Research Network (TCRN) database registry was used to gather historical data on 702 patients with common alpha and beta-Thalassemia diagnoses including Thalassemia Major (TM), Intermedia (TI), E/Beta, homozygous alpha Thalassemia (AT), Hemoglobin H disease (HbH) and HbH with Constant Spring (HbH/CS), who consented to a medical record chart review. Bone mineral density (BMD) measurements by DXA were available for review in a subgroup of patients (n = 312). The overall fracture prevalence among all Thalassemia syndromes was 12.1%, equally distributed between females (11.5%) and males (12.7%). Fractures occurred more frequently in TM (16.6%) and TI (12.2%) compared to E/Beta (7.4%) and alpha (2.3%). Prevalence increased with age (2.5% ages 0-10 years, 7.4% ages 11-19 years, 23.2% ages >20 years) and with use of sex hormone replacement therapy (SHRT) (P < 0.01). On average, BMD Z and T scores were 0.85 SD lower among patients with a history of fractures (mean Z/T score -2.78 vs. -1.93, 95% CI for the difference -0.49 to -1.22 SD, P = 0.02). Presence of other endocrinopathies (i.e. hypothyroidism, hypoparathyroidism and diabetes mellitus), anthropometric parameters, heart disease or hepatitis C were not significant independent predictors of fractures. These data indicate that fractures remain a frequent complication among the aging patients with both TM and TI beta-Thalassemia. However, the fracture prevalence has improved compared to published reports from the 1960s to 1970s. In addition, children with Thalassemia appear to have low fracture rates compared to the general population.
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PMID:Prevalence of fractures among the Thalassemia syndromes in North America. 1629 78

The life expectancy of patients with thalassemia major has significantly increased in recent years, as reported by several groups in different countries. However, complications are still frequent and affect the patients' quality of life. In a recent study from the United Kingdom, it was found that 50% of the patients had died before age 35. At that age, 65% of the patients from an Italian long-term study were still alive. Heart disease is responsible for more than half of the deaths. The prevalence of complications in Italian patients born after 1970 includes heart failure in 7%, hypogonadism in 55%, hypothyroidism in 11%, and diabetes in 6%. Similar data were reported in patients from the United States. In the Italian study, lower ferritin levels were associated with a lower probability of experiencing heart failure and with prolonged survival. Osteoporosis and osteopenia are common and affect virtually all patients. Hepatitis C virus antibodies are present in 85% of multitransfused Italian patients, 23% of patients in the United Kingdom, 35% in the United States, 34% in France, and 21% in India. Hepatocellular carcinoma can complicate the course of hepatitis. A survey of Italian centers has identified 23 such cases in patients with a thalassemia syndrome. In conclusion, rates of survival and complication-free survival continue to improve, due to better treatment strategies. New complications are appearing in long-term survivors. Iron overload of the heart remains the main cause of morbidity and mortality.
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PMID:Survival and complications in thalassemia. 1633 50

Magnetic resonance T2* values of the myocardium are directly related to tissue iron levels. Minor effects from myocardial oxygenation and fibrosis are overwhelmed by the highly dominant iron effect in clinically relevant levels of myocardial iron overload. Myocardial T2* values less than 20 ms indicate iron overload, and this is considered severe when T2* is less than 10 ms. Decreasing myocardial T2* levels are associated with systolic and diastolic ventricular dysfunction. Most recorded cases of heart failure in thalassemia to date have occurred in patients with very low T2* values (in the severe range). Exceptions to this have occurred in patients with other causes of heart failure such as concomitant congenital heart disease. In patients presenting with heart failure who undergo aggressive chelation with continuous intravenous deferoxamine, longitudinal studies show that myocardial T2* increases, and this is accompanied by increases in ejection fraction and relief of heart failure. In cross-sectional studies, the myocardial T2* and ejection fraction of patients on deferiprone was superior to that of patients on deferoxamine. Randomized controlled prospective trials comparing these two drugs for their action in clearing myocardial iron, as measured by myocardial T2*, are under way and should report in 2005/2006. These trials will clarify the role of different chelators in the management of myocardial iron overload and may be valuable in reducing the toll of death in thalassemia from heart failure.
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PMID:T2* magnetic resonance and myocardial iron in thalassemia. 1633 85

Iron cardiomyopathy remains the leading cause of death in patients with thalassemia major. Magnetic resonance imaging (MRI) is ideally suited for monitoring thalassemia patients because it can detect cardiac and liver iron burdens as well as accurately measure left ventricular dimensions and function. However, patients with thalassemia have unique physiology that alters their normative data. In this article, we review the physiology and pathophysiology of thalassemic heart disease as well as the use of MRI to monitor it. Despite regular transfusions, thalassemia major patients have larger ventricular volumes, higher cardiac outputs, and lower total vascular resistances than published data for healthy control subjects; these hemodynamic findings are consistent with chronic anemia. Cardiac iron overload increases the relative risk of further dilation, arrhythmias, and decreased systolic function. However, many patients are asymptomatic despite heavy cardiac burdens. We explore possible mechanisms behind cardiac iron-function relationships and relate these mechanisms to clinical observations.
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PMID:Physiology and pathophysiology of iron cardiomyopathy in thalassemia. 1633 87

Two hundred and seventy-three patients with thalassaemia major (TM) were followed in the Ferrara Thalassaemia Centre over a thirty-year period. Forty-two patients had insulin dependent diabetes mellitus (IDDM). The first case was diagnosed in 1973. The incidence of IDDM peaked in 1986 (3.9%), and it was 0.7% at the time of the study (March 1998). The prevalence of IDDM increased progressively over time, reaching 14.2% in 1998. Mean age at diagnosis of IDDM was 18.2 -/+ 3.6 years and this also rose significantly during the study period (p<0.01). Hypogonadism was present in 91% of patients with IDDM, hypothyroidism in 68%, hypoparathyroidism in 21%, and cardiopathy in 69%, all significantly more prevalent than in patients without IDDM. These complications appeared with the same frequency before and after the diagnosis of IDDM. Survival of patients with and without IDDM was similar and no difference in the primary cause of death was found between the two groups. Main risk factors associated with IDDM were poor compliance with desferioxamine (DFO) treatment (p<0.05%), advanced age at the start of intensive chelation therapy (p<0.001), liver cirrhosis or severe fibrosis (p<0.0001, odds ratio 9.5, CI 95% 2.8-32.6). Prevalence of impaired glucose tolerance (IGT) was highest in 1981, 1984, and 1985 when the incidence of IDDM was increasing; in 1995 the prevalence of IGT in patients aged 16-20 years was lower in comparison with that observed in 1975 (17% vs. 59%, p<0.01). Risk factors associated with IGT were: male sex (p<0.05), poor compliance with DFO therapy (p<0.05) and liver iron concentration 4 times above the normal value. In conclusion, our longitudinal study confirms that the incidence of IDDM and prevalence of IGT have been decreasing over the course of the last decade, appearing at a more advanced age, although some differences have not reached statistical significance. Iron overload and liver disease were the main associated risk factors, while positive family history for diabetes did not influence glucose metabolism in our patients.
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PMID:Diabetes mellitus and impaired glucose tolerance in thalassaemia major: incidence, prevalence, risk factors and survival in patients followed in the Ferrara Center. 1646 13

Heart disease is the leading cause of mortality and one of the main causes of morbidity in beta-thalassemia. The clinical spectrum of the thalassemia syndrome ranges from the severe, transfusion--dependent thalassemia major and the asymptomatic carrier state. Thalassemia intermedia represents a milder form and is usually transfusion-independent. Two main factors determine cardiac disease in this form. One is the high output state that results from chronic tissue hypoxia and from hypoxia-induced compensatory reactions. The other is the vascular involvement that leads to an increased pulmonary vascular resistance and an increased systemic vascular stiffness. Valvular abnormalities and iron overload also contribute to a less extent. As a result, both right and left ventricles have to maintain a high cardiac output level through a stiff vascular bed. Right heart involvement with age-related pulmonary hypertension followed by congestive heart failure dominates the clinical picture. Although the left heart is also affected, systolic left ventricular function is usually preserved but this may also be decompensated under conditions characterized by excessive cardiac work load.
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PMID:Heart disease in thalassemia intermedia: a review of the underlying pathophysiology. 1748 90

Thalassemia is anemia of variable severity, arising from mutations of genes encoding the hemoglobin alpha and beta chains. Severe thalassemia is associated with iron overload, tissue lesions, and high risk for cardiovascular complications, and iron-mediated cardiomyopathy is the main cause of death in this condition. Thalassemia major (TM) patients exhibit cardiovascular abnormalities consistent with chronic anemia; these include enlargement of the ventricular chambers, increased cardiac output, and reduced total vascular resistance. Cardiac iron overload in TM patients due to long-term transfusion can cause further chamber dilation, decreased contractility, and arrhythmia. Paradoxically, many such patients remain asymptomatic until decompensation occurs. For decades, magnetic resonance imaging and echocardiography have been performed to detect advanced cardiac dysfunction; however, reliable evaluation tools for the early detection of cardiac abnormalities are currently in demand. This article reviews the mechanisms underlying the development of heart disease in thalassemia and strategies for therapeutic intervention in TM patients with congestive heart failure.
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PMID:Mechanisms of and obstacles to iron cardiomyopathy in thalassemia. 1850 36


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