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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Jehovah's Witness who require operation represent a challenge to the physician because of the patients' refusal to accept blood transfusion. We report an 8-year-old male of Jehovah's Witness who underwent a surgical treatment of infective endocarditis. He was transferred to our hospital because of high fever and heart murmur. Echocardiogram revealed a developing vegetation of aortic cusps and an aneurysmal change of the non-coronary sinus Valsalva. On admission he was complicated by anemia, purulent meningitis and suppurative arthritis of left knee. There were no signs of cardiac failure. Erythropoietin (6000 U thrice weekly) and iron (60 mg daily) were given for 11 weeks prior to surgery, raising the hemoglobin level from 9.2 g/dl to 18.4 g/dl. Aortic valve replacement and plasty of the sinus Valsalva were then performed. Intraoperatively hemoglobin concentration dropped to 10.3 g/dl and it raised to 15 g/dl postoperatively. We also used Cell-Saver to reduce blood loss. The patient made an uncomplicated recovery. Erythropoietin therapy contributed substantially to the successful outcome of this case.
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PMID:[Open heart surgery in a Jehovah's Witness boy--a case report of successful management of aortic regurgatation and aneurysm of sinus Valsalva due to infective endocarditis]. 945 16

Patients with homozygous beta-thalassemia are chronically transfused and, if not assiduously chelated, are at risk for cardiac dysfunction. Available data suggest that even in optimally chelated patients, cardiac pathology is abnormal secondary to iron deposition, fibrosis, hypertrophy, and the structural effects of chronic anemia. Evidence of myopericarditis may also be found. Cardiac performance is usually only subtly affected, primarily with diastolic abnormalities not routinely detected on echocardiograms or nuclear scan. In poorly chelated patients, severe heart failure occurs and is easily predictable but invariably fatal, despite treatment with diuretics, vasodilators, inotropes, and antiarrhythmics. Based on successful prevention of heart failure with ACE inhibitors in other forms of cardiomyopathy, we suggest multicenter trials to explore methods to stabilize cardiac function in patients at risk for iron-induced heart disease. Long-term adverse effects of iron deposition, diastolic dysfunction, and abnormal hormone regulation need to be quantitated in patients reaching their third and fourth decades when the potential for ischemic cardiac disease could compound cardiac dysfunction.
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PMID:Diagnosis and management of iron-induced heart disease in Cooley's anemia. 966 46

In homozygous beta-thalassemia, the organ damage is mainly attributed to excessive iron deposition through the formation of oxygen free radicals. Despite appropriate transfusion and chelation therapy and low ferritin levels, patients still develop organ failure, heart failure being the main cause of death. This study was designed to determine whether the decreased antioxidant activity of the apolipoprotein E (APOE) 4 allele could represent a genetic risk factor for the development of left ventricular failure (LVF) in beta-thalassemia homozygotes. A total of 251 Greek beta-thalassemia homozygotes were studied. Patients were divided in three groups: group A (n = 151) with no cardiac impairment, group C (n = 47) with LVF, and 53 patients with LV dilatation and normal LV systolic function constituted the group B. DNA was obtained from all patients, and the polymerase chain reaction was used to analyze the polymorphism at the APOE locus. The APOE allele frequencies were compared with those of a Greek control sample of 216 healthy blood donors. Patients with no cardiac impairment had an APOE 4 allele frequency (7.9%) not different from population controls (6.5%, P > .05), while patients with LVF had a significantly higher frequency of APOE 4 (12.8%) than the controls (P < .05, odds ratio = 2.11, 95% confidence interval 1.03 to 4.32). The APOE 4 allele may represent an important genetic risk factor for the development of organ damage in homozygous beta-thalassemia.
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PMID:Apolipoprotein E epsilon4 allele as a genetic risk factor for left ventricular failure in homozygous beta-thalassemia. 978 87

Iron-induced cardiac disease is the primary cause of death in transfused patients with thalassaemia major. The beneficial effects of deferoxamine mesylate on clinical cardiac disease have been well described but the impact of therapy on subclinical cardiac dysfunction is unknown. To assess the reversibility of subclinical cardiac dysfunction we studied the cardiac status during iron depletion treatment (phlebotomy) in iron overloaded patients, cured of thalassaemia by marrow transplantation, without clinical manifestation of heart failure but with alteration in both left ventricular diastolic function and in contractility property. 32 patients were studied and demonstrated a slight but significant impairment in the morphology and function if compared with matched normal controls. 17 of these patients were submitted to sequential echocardiographic evaluations during the phlebotomy programme. Following completion of the programme, normalization of the indices of contractility and normalization of diastolic function were observed. This study indicates that transplanted thalassaemia patients with subclinical left ventricular diastolic dysfunction and impaired left ventricular contractility may reverse these processes with an effective regimen of iron reduction such as phlebotomy.
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PMID:Evaluation of cardiac status in iron-loaded thalassaemia patients following bone marrow transplantation: improvement in cardiac function during reduction in body iron burden. 988 1

Juvenile haemochromatosis (JH) is an autosomal recessive disorder which leads to early-onset, severe iron overload. The disease affects both sexes equally. Iron parameters and tissue iron distribution are similar to those in middle-life haemochromatosis (which is linked to the HFE gene). Endocrine manifestations, especially hypogonadism, and heart failure are the most prominent clinical features. Liver involvement, although present, is clinically less relevant. Genetic evidence indicates that JH is a disorder distinct from HFE-linked disease. Patients do not have mutations in the HFE gene, and the study of selected families has excluded a linkage to the interval of chromosome 6p where the HFE gene resides. The distinction between the two disorders raises the possibility that the different clinical presentation of JH is not only age-related but probably depends on a different biochemical defect. Early diagnosis of JH is important to avoid cardiac complications which can lead to premature death. As with HFE-linked disease, JH is responsive to phlebotomies.
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PMID:Juvenile haemochromatosis. 989 70

Juvenile haemochromatosis is a rare inborn error of iron metabolism with clinical manifestations before 30 years of age. Unlike adult haemochromatosis which principally affects men, juvenile haemochromatosis affects the sexes equally; it causes early endocrine failure, dilated cardiomyopathy and joint disease. We report four patients (two of each sex) from three pedigrees affected by juvenile haemochromatosis with a mean onset at 22 years (range 14-30). All had endocrine deficiency with postpubertal gonadal failure secondary to pituitary disease; two suffered near-fatal cardiomyopathy with heart failure. Mean time to diagnosis from the first clinical signs of disease was 9.8 years (range 0.5-20) but general health and parameters of iron storage responded favourably to iron-depletion therapy. A 24-year-old man listed for heart transplantation because of cardiomyopathy [left ventricular (LV) ejection fraction 16%] responded to intravenous iron chelation with desferrioxamine combined with phlebotomy (ejection fraction 31%). A 27-year-old woman with subacute biventricular heart failure refractory to medication required orthotopic cardiac transplantation before the diagnosis was established (LV ejection fraction 25%). Genetic studies showed that these two patients with cardiomyopathy from unrelated families were heterozygous for the HFE 845G-->A (C282Y) mutation and wild-type at the H63D locus: complete sequencing of the intron-exon boundaries and entire coding sequence of the HFE gene failed to identify additional lesions. Two siblings in a pedigree without cardiomyopathy were wild-type at the HFE C282Y locus; although the brother harboured a single copy of the 187C-->G (H63D) allele, segregation analysis showed that in neither sibling was the iron-storage disease linked to MHC Class I markers on chromosome 6p. Juvenile haemochromatosis is thus a genetically heterogenous disorder distinct from the common adult variant.
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PMID:Hereditary juvenile haemochromatosis: a genetically heterogeneous life-threatening iron-storage disease. 1002 15

In Eisenmenger's syndrome a central left-to-right shunt in the heart, a congenital anomaly, leads to pulmonary hypertension which subsequently causes the shunt to be reversed. The hypoxaemia resulting from a right-to-left shunt is compensated by an increase of the haemoglobin concentration due to a rise of the haematocrit. In adult patients not operated (adequately), the symptoms are the consequence of the erythrocytaemia and an increased haemorrhagic diathesis. In the long run heart failure develops. Phlebotomy is indicated for patients with haematocrits higher than 0.65 with signs of hyperviscosity and is also advised before non-cardiac surgery to improve coagulation parameters. Phlebotomy should be performed slowly (500 ml in 30-45 min) with simultaneous volume replacement. Excessive phlebotomy causes iron deficiency and spherocytosis which increase viscosity as well as the risk of CVA. Treatment consists of iron supplementation. Anticoagulation is indicated only in case of atrial fibrillation or mechanical valves. The use of acetylsalicylacid or NSAIDs is relatively contraindicated, because of abnormal haemostasis in these patients. During treatment with ACE inhibitors and other vasodilators, hypovolaemia should be avoided, because at a lower systemic blood pressure the right-to-left shunt increases and a potentially fatal cyanosis may occur.
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PMID:[Eisenmenger syndrome in adults]. 1032 Dec 57

Adjuvant therapy may allow patients being treated with epoetin to derive greater clinical benefits. Iron supplementation is currently the most widely used form of adjuvant therapy; intravenous (i.v.) iron is required by the majority of haemodialysis patients receiving epoetin. Measurement of hypochromic red blood cells is the most direct way of assessing iron supply to the bone marrow. During the correction phase, a dose of i.v. iron equivalent to 50 mg/day is recommended, with the total dose not exceeding 3 g. When subclinical vitamin C deficiency is suspected, ascorbic acid may be given orally (1-1.5 g/week) or i.v. (300 mg three times weekly at the end of dialysis). The active vitamin D metabolites alfacalcidol and calcitriol may, under some circumstances, improve anaemia and reduce epoetin dosage requirements. Vitamin B6 requirements are increased during epoetin therapy, and supplementation at a dose of 100-150 mg/week is recommended. Supplementation of vitamin B12 is optional. Folic acid is supplemented routinely in haemodialysis patients, though evidence that it increases the efficacy of epoetin is limited. Low doses (2-3 mg/week) should normally be sufficient to maintain optimal folic acid stores in epoetin-treated patients, although higher doses are necessary for patients with hyperhomocysteinaemia. L-Carnitine supplementation may be appropriate in some patients with anaemia of chronic renal failure (CRF) unresponsive to, or requiring large doses of, epoetin. Androgens potentially could reduce epoetin costs in countries with limited resources, but should only be used in men older than 50 years with a remnant kidney. Recent animal studies indicate that the combination of epoetin and insulin-like growth factor 1 might be beneficial in CRF patients. High doses of angiotensin-converting enzyme (ACE) inhibitors should be reserved for dialysis patients who have hypertension that cannot be controlled by other agents, or who require an ACE inhibitor for treatment of heart failure.
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PMID:Is there a role for adjuvant therapy in patients being treated with epoetin? 1057 78

Heart failure is the leading cause of mortality in patients with transfusional iron (Fe) overload in which myocardial iron uptake ensues via a transferrin-independent process. We examined the ability of L-type Ca2+ channel modifiers to alter Fe2+ uptake by isolated rat hearts and ventricular myocytes. Perfusion of rat hearts with 100 nmol/L 59Fe2+ and 5 mmol/L ascorbate resulted in specific 59Fe2+ uptake of 20.4+/-1.9 ng of Fe per gram dry wt. Abolishing myocardial electrical excitability with 20 mmol/L KCl reduced specific 59Fe2+ uptake by 60+/-7% (P<0.01), which suggested that a component of myocardial Fe2+ uptake depends on membrane voltage. Accordingly, 59Fe2+ uptake was inhibited by 10 micromol/L nifedipine (45+/-12%, P<0.02) and 100 micromol/L Cd2+ (86+/-3%; P<0. 001) while being augmented by 100 nmol/L Bay K 8644 (61+/-18%, P<0. 01) or 100 nmol/L isoproterenol (40+/-12%, P<0.05). By contrast, uptake of 100 nmol/L ferric iron (59Fe3+) was significantly lower (1. 4+/-0.3 ng Fe per gram dry wt; P<0.001) compared with divalent iron. These data suggest that a component of Fe2+ uptake into heart occurs via the L-type Ca2+ channel in myocytes. To investigate this further, the effects of Fe2+ on cardiac myocyte L-type Ca2+ currents were measured. In the absence of Ca2+, noninactivating nitrendipine-sensitive Fe2+ currents were recorded with 15 mmol/L [Fe2+]o. Low concentrations of Fe2+ enhanced Ca2+ current amplitude and slowed inactivation rates, which was consistent with Fe2+ entry into the cell, whereas higher Fe2+ levels caused dose-dependent decreases in peak current. Fe3+ had no effect on current amplitude or decay. Combined, our data suggest that myocardial Fe2+ uptake occurs via L-type Ca2+ channels and that blockade of these channels might be useful in the treatment of patients with excessive serum iron levels.
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PMID:Modulation of iron uptake in heart by L-type Ca2+ channel modifiers: possible implications in iron overload. 1036 68

Universal screening for hereditary hemochromatosis (HH) has been proposed by many experts, with understandable enthusiasm: HH can cause fatal complications, which are preventable with early treatment. The disorder involves excess iron accumulation that can result in tissue iron overload, with secondary cirrhosis, diabetes, heart failure, impotence and arthritis. These complications are preceded by years of iron accumulation, and most are believed to be preventable by removal of excess iron by phlebotomy. Thus, early identification and treatment - the quintessential functions of health screening - seem to make sense for HH. However, the available screening tests are imperfect. While they can identify many persons at increased risk from HH, the proportion that will develop serious clinical manifestations related to iron overload is not known with certainty. DNA-based tests do not provide a simple resolution to these questions.
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PMID:Screening for hereditary hemochromatosis: are DNA-based tests the answer? 1049 10


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