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

Hereditary hemochromatosis is a common disorder of iron metabolism with a prevalence as high as 8 per 1000. Affected individuals absorb excessive amounts of dietary iron and over time, tissue iron deposition results in skin discoloration, arthropathy, hepatic cirrhosis, heart failure, diabetes mellitus and impotence. Early diagnosis and institution of phlebotomy treatments will prevent these manifestations and normalize life expectancy. Once organ damage is established many of the manifestations are irreversible. Since the early manifestations of the disease are subtle, a case can be made for routine screening. This conclusion is supported by cost-effectiveness analysis based on available data. A reasonable screening strategy would start with a serum transferrin saturation. A value > or = 55% should trigger a repeat transferrin saturation in a fasting state and a serum ferritin level. If both these tests are abnormal, a liver biopsy with quantitative iron determination is the currently accepted confirmatory test.
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PMID:Management of hereditary hemochromatosis. 788 27

Accumulation of Fe in the myocardium in circumstances of transferrin saturation is associated with heart failure in Fe-loaded patients. To characterize the underlying causes of this phenomenon, we measured the flux as well as the speciation of Fe in normal and Fe-loaded cultures of rat myocardiocytes. Fe loading with low-molecular-weight Fe (ferric ammonium citrate) promoted a dose- and time-dependent increase in the rate of uptake of non-transferrin-bound Fe (NTBI) that was positively correlated (R = 0.9, p < 0.005) with cellular iron content. At concentrations sufficient to produce this up-regulation, membrane integrity was unaffected but the rate of spontaneous beating of the cells was decreased by 60%. The enhanced rate of NTBI uptake in Fe-loaded cells reverted to control rates after treatment with therapeutic concentrations of Fe chelators deferoxamine, 1,2-dimethyl-3-hydroxypyrid-4-one and 1,2-diethyl-3-hydroxypyrid-4-one under conditions where approximately 80% of the cellular Fe was removed by chelation. Fe loading of cultured myocytes also induced shifts in Fe speciation. Thus the ratio of Fe bound in hemosiderin-like precipitates to ferritin-bound Fe increased twofold, from a range of 0.84 to 1.44 in control cells to 1.96 to 3.3 in iron-loaded cells. This increased ratio was similar to that measured in the heart and liver of a thalassemic patient who underwent a double transplant for the failure of both organs, even though the Fe content of the heart (mean, 5.8 mg Fe/gm dry weight) was much less than that of the liver (28.1 mg/gm dry weight). These results suggest that increased rates of uptake of NTBI may exacerbate iron loading of the heart and contribute to iron-mediated cardiotoxicity, whereas the clinical benefits of chelation therapy may be enhanced by the down-regulation of NTBI uptake.
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PMID:Effects of iron loading on uptake, speciation, and chelation of iron in cultured myocardial cells. 832 Apr 86

In order to study nutritional assessment and nutritional support therapy for elderly patients, we conducted energy supply therapy on 15 elderly (aged over 75) patients disabled with diseases such as cerebrovascular disease, pneumonia and heart failure. After recovery from acute phase, they were divided into 3 groups, and assigned to 3 different energy supply methods for 2 weeks: Six (3 males, 3 females) could take hospital diet, but only could absorb about 50% of the energy, amounting only 1,000 to 1,400 kcal/day. Additional 246 kcal was given by peripheral parental nutrition (PPN). Five (2 males, 3 females) were unable to take nutrition orally. Therefore, they were given high caloric nutrients by total parental nutrition (TPN), giving (1,222 kcal daily for a week), then 1,666 kcal for another week. Four (1 male, 3 females) also could not take meals orally, and had to be nourished by enteral nutrition (EN) with a nutrient preparation of 1,120 kcal for one week, then with 1,600 kcal for another week. In all 3 groups, the indices of rapid turnover proteins (pre-albumin, retinol binding protein and transferrin), choline esterase and vitamin A significantly elevated after 2 weeks of therapy, though the increase of pre-albumin and RBP in TPN group was slightly below the significant level. The increase in rapid turnover proteins and choline esterase was greater in the order of EN, TPN and PPN. Vitamin C, on the other hand, decreased significantly with treatment in all the groups, while vitamin E remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Nutritional assessment and nutritional support therapy in elderly patients]. 836 Oct 76

Chronic mild liver enzyme abnormalities are attributable to hereditary hemochromatosis in at least 3% of cases. Hemochromatosis formerly was diagnosed late with diabetes and hepatic and cardiac failure. Only recently have the autosomal recessive inheritance and subtle early presentations been understood. However, patients still wait many years and see many physicians before receiving a correct diagnosis. Increased serum transferrin saturation is currently the best test for detection of those likely to accumulate iron. Serum ferritin identifies those requiring treatment. When liver biopsy (controversial in asymptomatic individuals) is indicated, chemical measurement of liver iron content is helpful and therapeutic phlebotomy is the only effective treatment. Caucasian-type hemochromatosis (prevalence of 0.005) is associated with genetic abnormalities in HLA-H but also occurs in other ethnic groups. Those of African descent may have a different but also heritable iron-loading disease. Caucasian-type and to a lesser extent African iron loading are detectable early by laboratory testing. Early treatment restores normal expectations of length and quality of life in the Caucasian disease. Long-term treatment data are not yet available in African iron loading. Laboratory-initiated screening programs using unsaturated iron-binding capacity can eliminate symptomatic hemochromatosis.
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PMID:Mild liver enzyme abnormalities: eliminating hemochromatosis as cause. 926 5

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

Hereditary hemochromatosis (HHC) is one of the most common inherited disorders in the Caucasian population. Diagnosis usually made after an elevation in ferritin and serum transferrin saturation is noted, often accompanied by asymptomatic hepatomegaly. Diagnosis is confirmed by genetic testing or liver biopsy. Damage to organs is due to excessive intestinal iron, which is transported to and then deposited in the liver parenchyma, and the heart, skin, and endocrine organs, causing skin pigmentation, development of cirrhosis and hepatic carcinoma, diabetes and endocrine failure, and heart failure. Bony changes can be manifested by arthritis, often in non-weight-bearing joints. The treatment of HHC is phlebotomy, which depletes iron stores. When diagnosis is made before organ damage occurs, treatment can prevent manifestations of the disease. Skin pigmentation and some cardiac damage may reverse on depletion of iron stores, but liver and endocrine damage is rarely reversible. Arthropathy is also not reversible, and often continues to progress even with effective treatment. When hemochromatosis is diagnosed, all first degree relatives of the patient should undergo genetic testing. With early detection and treatment this can be a manageable chronic disease. If undetected, it is potentially fatal.
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PMID:Hereditary hemochromatosis: diagnosis and treatment in primary care. 1054 25

A case of protein-losing enteropathy associated with aortic stenosis and without signs of right-sided heart failure is described. The protein loss was diagnosed and quantitated by 111Indium-transferrin imaging and whole-body retention. The intestinal loss of protein decreased from 35% to 5% after implantation of a mechanical aorta valve.
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PMID:[Aortic stenosis as a cause of protein-losing enteropathy]. 1181 Aug 2

Juvenile hemochromatosis or type 2 hemochromatosis is a rare inherited recessive disease, which leads to severe iron overload earlier in life than HFE-related hemochromatosis. Increased transferrin saturation and serum ferritin as well as parenchymal iron deposition and liver fibrosis may be observed in childhood. Clinical symptoms of hypogonadism and cardiac disease develop before the age of 30. The disease is usually progressive and if untreated may become fatal because of heart failure. The type 2 hemochromatosis locus maps to chromosome 1q21, but the gene has not yet been isolated. The severity and the early expression of juvenile hemochromatosis suggest that the gene product has a crucial role in the regulation of iron homeostasis.
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PMID:Juvenile hemochromatosis. 1238 99

Heart failure (HF) is a slow progressive syndrome characterized by low cardiac output and peripheral metabolic, biochemical, and histological alterations. Protein loss and reduced protein turnover occur with aging, but the consequences of congestive HF (CHF) superimposed on the normal aging response are unknown. This study has two objectives: 1) to determine whether there was a difference between older age-matched controls and those with stable HF (i.e., ischemic pathology) in whole body protein turnover and 2) to determine whether protein metabolism in liver and skeletal muscle protein turnover is impacted by CHF. We measured the whole body protein synthesis rate with a U-(15)N-labeled algal protein hydrolysate in 10 patients with CHF and in 10 age-matched controls. Muscle fractional synthesis rate of lateral vastus muscle was determined with [U-(13)C]alanine on muscle biopsies obtained by a standard percutaneous needle biopsy technique. Fractional synthesis rates of five plasma proteins of hepatic origin (fibrinogen, complement C-3, ceruloplasmin, transferrin, and very low-density lipoprotein apoliprotein B-100) were determined by using (2)H(5)-labeled l-phenylalanine as tracer. Results showed that whole body protein synthesis rate was reduced in CHF patients (3.09 +/- 0.19 vs. 2.25 +/- 0.71 g protein x kg(-1) x day(-1), P < 0.05) as was muscle fractional synthesis rate (3.02 +/- 0.58 vs. 1.33 +/- 0.71%/day, P < 0.05) and very low-density lipoprotein apoliprotein B-100 (265 +/- 25 vs. 197 +/- 16%/day, P < 0.05). CHF patients were hyperinsulinemic (9.6 +/- 3.1 vs. 47.0 +/- 7.8 microU/ml, P < 0.01). The results were compared with those found with bed rest patients. In conclusion, protein turnover is depressed in CHF patients, and both skeletal muscle and liver are impacted. These results are similar to those found with bed rest, which suggests that inactivity is a factor in depressed protein metabolism.
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PMID:Protein kinetics in stable heart failure patients. 1239 Oct 30

Genetic haemochromatosis is an autosomal recessive inherited disorder of iron metabolism due to mutation of the HFE gene. In homozygotes (1 in 300 of the UK population), this results in excessive iron absorption from the gut and its deposition in major body organs. This may give rise to fatigue, arthritis, cardiac failure, diabetes mellitus, hepatic cirrhosis or skin pigmentation, occurring predominantly in males over 50 years of age. Identification uses measurement of serum iron, iron-binding capacity (or transferrin) and ferritin, together with initial or confirmatory genetic DNA studies.
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PMID:Genetic haemochromatosis. 1242 71


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