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1.
Braz J Med Biol Res ; 50(12): e6327, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28977120

RESUMO

Heart failure is characterized by the inability of the cardiovascular system to maintain oxygen (O2) delivery (i.e., muscle blood flow in non-hypoxemic patients) to meet O2 demands. The resulting increase in fractional O2 extraction can be non-invasively tracked by deoxygenated hemoglobin concentration (deoxi-Hb) as measured by near-infrared spectroscopy (NIRS). We aimed to establish a simplified approach to extract deoxi-Hb-based indices of impaired muscle O2 delivery during rapidly-incrementing exercise in heart failure. We continuously probed the right vastus lateralis muscle with continuous-wave NIRS during a ramp-incremental cardiopulmonary exercise test in 10 patients (left ventricular ejection fraction <35%) and 10 age-matched healthy males. Deoxi-Hb is reported as % of total response (onset to peak exercise) in relation to work rate. Patients showed lower maximum exercise capacity and O2 uptake-work rate than controls (P<0.05). The deoxi-Hb response profile as a function of work rate was S-shaped in all subjects, i.e., it presented three distinct phases. Increased muscle deoxygenation in patients compared to controls was demonstrated by: i) a steeper mid-exercise deoxi-Hb-work rate slope (2.2±1.3 vs 1.0±0.3% peak/W, respectively; P<0.05), and ii) late-exercise increase in deoxi-Hb, which contrasted with stable or decreasing deoxi-Hb in all controls. Steeper deoxi-Hb-work rate slope was associated with lower peak work rate in patients (r=-0.73; P=0.01). This simplified approach to deoxi-Hb interpretation might prove useful in clinical settings to quantify impairments in O2 delivery by NIRS during ramp-incremental exercise in individual heart failure patients.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Hemoglobinas/análise , Perna (Membro)/irrigação sanguínea , Músculo Esquelético/metabolismo , Consumo de Oxigênio/fisiologia , Estudos de Casos e Controles , Teste de Esforço , Insuficiência Cardíaca/metabolismo , Humanos , Perna (Membro)/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Estudos Prospectivos , Espectroscopia de Luz Próxima ao Infravermelho
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;50(12): 6327, 2017. tab, graf
Artigo em Inglês | LILACS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-888973

RESUMO

Heart failure is characterized by the inability of the cardiovascular system to maintain oxygen (O2) delivery (i.e., muscle blood flow in non-hypoxemic patients) to meet O2 demands. The resulting increase in fractional O2 extraction can be non-invasively tracked by deoxygenated hemoglobin concentration (deoxi-Hb) as measured by near-infrared spectroscopy (NIRS). We aimed to establish a simplified approach to extract deoxi-Hb-based indices of impaired muscle O2 delivery during rapidly-incrementing exercise in heart failure. We continuously probed the right vastus lateralis muscle with continuous-wave NIRS during a ramp-incremental cardiopulmonary exercise test in 10 patients (left ventricular ejection fraction <35%) and 10 age-matched healthy males. Deoxi-Hb is reported as % of total response (onset to peak exercise) in relation to work rate. Patients showed lower maximum exercise capacity and O2 uptake-work rate than controls (P<0.05). The deoxi-Hb response profile as a function of work rate was S-shaped in all subjects, i.e., it presented three distinct phases. Increased muscle deoxygenation in patients compared to controls was demonstrated by: i) a steeper mid-exercise deoxi-Hb-work rate slope (2.2±1.3 vs 1.0±0.3% peak/W, respectively; P<0.05), and ii) late-exercise increase in deoxi-Hb, which contrasted with stable or decreasing deoxi-Hb in all controls. Steeper deoxi-Hb-work rate slope was associated with lower peak work rate in patients (r=-0.73; P=0.01). This simplified approach to deoxi-Hb interpretation might prove useful in clinical settings to quantify impairments in O2 delivery by NIRS during ramp-incremental exercise in individual heart failure patients.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Hemoglobinas/análise , Músculo Esquelético/metabolismo , Insuficiência Cardíaca/fisiopatologia , Perna (Membro)/irrigação sanguínea , Estudos de Casos e Controles , Estudos Prospectivos , Músculo Esquelético/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho , Teste de Esforço , Insuficiência Cardíaca/metabolismo , Perna (Membro)/fisiopatologia
4.
Thorax ; 63(10): 910-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18492743

RESUMO

BACKGROUND: Respiratory muscle unloading during exercise could improve locomotor muscle oxygenation by increasing oxygen delivery (higher cardiac output and/or arterial oxygen content) in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixteen non-hypoxaemic men (forced expiratory volume in 1 s 42.2 (13.9)% predicted) undertook, on different days, two constant work rate (70-80% peak) exercise tests receiving proportional assisted ventilation (PAV) or sham ventilation. Relative changes (Delta%) in deoxyhaemoglobin (HHb), oxyhaemoglobin (O(2)Hb), tissue oxygenation index (TOI) and total haemoglobin (Hb(tot)) in the vastus lateralis muscle were measured by near-infrared spectroscopy. In order to estimate oxygen delivery (Do(2)est, l/min), cardiac output and oxygen saturation (Spo(2)) were continuously monitored by impedance cardiography and pulse oximetry, respectively. RESULTS: Exercise tolerance (Tlim) and oxygen uptake were increased with PAV compared with sham ventilation. In contrast, end-exercise blood lactate/Tlim and leg effort/Tlim ratios were lower with PAV (p<0.05). There were no between-treatment differences in cardiac output and Spo(2) either at submaximal exercise or at Tlim (ie, Do(2)est remained unchanged with PAV; p>0.05). Leg muscle oxygenation, however, was significantly enhanced with PAV as the exercise-related decrease in Delta(O(2)Hb)% was lessened and TOI was improved; moreover, Delta(Hb(tot))%, an index of local blood volume, was increased compared with sham ventilation (p<0.01). CONCLUSIONS: Respiratory muscle unloading during high-intensity exercise can improve peripheral muscle oxygenation despite unaltered systemic Do(2 )in patients with advanced COPD. These findings might indicate that a fraction of the available cardiac output had been redirected from ventilatory to appendicular muscles as a consequence of respiratory muscle unloading.


Assuntos
Exercício Físico/fisiologia , Oxigênio/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Músculos Respiratórios/fisiologia , Dióxido de Carbono/sangue , Dióxido de Carbono/fisiologia , Débito Cardíaco/fisiologia , Tolerância ao Exercício/fisiologia , Humanos , Masculino , Músculo Esquelético/fisiologia , Oxigênio/sangue , Consumo de Oxigênio/fisiologia , Pressão Parcial , Respiração Artificial , Espectroscopia de Luz Próxima ao Infravermelho
5.
Hum Immunol ; 67(1-2): 22-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16698421

RESUMO

Apoptosis mediated by the Fas/Fas ligand (FasL) has been implicated in rejection of solid organ allografts and it has been recently proposed that soluble forms of Fas could interfere with this interaction, blocking apoptosis. The purpose of this study was to analyze intragraft Fas, FasL, and soluble Fas mRNA levels in relation to acute rejection in cardiac allografts in humans. mRNA levels were determined by quantitative reverse transcriptase-polymerase chain reaction in 42 samples of endomyocardial biopsies obtained from 18 cardiac transplant recipients within the first 6 months after transplantation. FasL and Fas mRNA levels were higher in biopsies with rejection than in biopsies without rejection, and no difference was observed in soluble Fas mRNA. During rejection, there was a positive correlation between the mRNA levels of Fas-FasL, Fas-soluble Fas, and FasL-soluble Fas. During quiescent periods, however, the only correlation observed was between Fas and soluble Fas mRNA levels. In conclusion, our findings do not suggest a role for soluble Fas, confirm the heightened expression of FasL, and indicate, for the first time, an increased expression of Fas in acute rejection of cardiac allografts.


Assuntos
Rejeição de Enxerto/genética , Transplante de Coração/imunologia , Glicoproteínas de Membrana/genética , Miocárdio/patologia , Fatores de Necrose Tumoral/genética , Receptor fas/genética , Adulto , Proteína Ligante Fas , Feminino , Expressão Gênica , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Transplante de Coração/patologia , Humanos , Masculino , Miocárdio/imunologia , RNA Mensageiro/análise
6.
Neurology ; 66(1): 124-6, 2006 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-16401862
7.
Transplant Proc ; 35(4): 1344-5, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12826155

RESUMO

It was recently shown that IL-2 gene single nucleotide polymorphism (SNP) at position -330 (G-->T) is related to in vitro cytokine production levels, with the T/T and T/G genotypes being associated with low production and the G/G genotype associated with high production. The objective of this study was to investigate a possible influence of this polymorphism on renal and cardiac allograft outcomes. IL-2 SNP G-T (-330) was determined by PCR-RFLP in 67 recipients of heart allografts and in 63 recipients of renal grafts from HLA-haplo-identical, related donors. A higher frequency of the T/T genotype was observed in renal transplant patients who experienced at least one acute rejection episode during the first 3 months after transplantation than in those without rejection during this period (80% vs 49%, respectively, P <.05). Accordingly, the same genotype tended to be more frequent in renal recipients with a 6-month serum creatinine level above 1.5 mg/dL (median value for the whole group of kidney recipients) than in patients with lower creatinine levels (79% vs 45%, P <.08). Regarding cardiac transplant recipients, no associations were observed concerning acute rejection or graft survival. The finding of the association of T/T but not T/G genotype with acute kidney rejection was unexpected considering that both genotypes were shown to be associated with equal (low) IL-2 in vitro production. Further studies are necessary not only to dissect the nature of IL-2 T/T genotype association with kidney rejection, but also to explain why this genotype does not apparently influence cardiac allograft outcome.


Assuntos
Transplante de Coração/imunologia , Interleucina-2/genética , Transplante de Rim/imunologia , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Doença Aguda , Creatinina/sangue , Genótipo , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Fenótipo , Polimorfismo de Fragmento de Restrição , Fatores de Tempo , Resultado do Tratamento
9.
Transplantation ; 72(10): 1705-8, 2001 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-11726838

RESUMO

BACKGROUND: The purpose of the present study was to investigate transcripts of perforin, granzyme B, and Fas ligand (FasL) in heart transplants undergoing rejection. METHODS: Quantitative reverse transcriptase-polymerase chain reaction was applied for mRNA detection in 29 endomyocardial biopsy specimens from 11 cardiac allograft recipients. RESULTS: The mRNA levels of granzyme B, perforin, and FasL were higher (P<0.05) in biopsy specimens with rejection than in biopsy specimens without rejection (granzyme B, 0.53 vs. 0.09; perforin, 0.34 vs. 0; FasL, 0.57 vs. 0.36). In prerejection biopsy specimens, granzyme B and FasL levels were significantly higher than in biopsy specimens without rejection. Any two of the three transcripts were increased in 100% of prerejection, in 92% of rejection, and in 36% of no rejection biopsy specimens (P<0.04). CONCLUSIONS: The assessment of intragraft levels of cytotoxic T lymphocyte effector molecule mRNA represents a valuable tool in the monitoring of cardiac allograft rejection, especially considering the predictive value for warning of impending acute rejection.


Assuntos
Regulação da Expressão Gênica , Rejeição de Enxerto , Transplante de Coração/imunologia , Glicoproteínas de Membrana/genética , Serina Endopeptidases/genética , Linfócitos T Citotóxicos/fisiologia , Proteína Ligante Fas , Granzimas , Humanos , Perforina , Proteínas Citotóxicas Formadoras de Poros , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;34(6): 779-84, Jun. 2001. tab, graf
Artigo em Inglês | LILACS | ID: lil-285853

RESUMO

The purpose of the present study was to investigate the expression (mRNA) of CD40 ligand (CD40L), interferon-gamma (IFN-gamma) and Fas ligand (FasL) genes in human cardiac allografts in relation to the occurrence of acute cardiac allograft rejection as well as its possible value in predicting acute rejection. The mRNA levels were determined by a semiquantitative reverse transcriptase-polymerase chain reaction method in 39 samples of endomyocardial biopsies obtained from 10 adult cardiac transplant recipients within the first six months after transplantation. Biopsies with ongoing acute rejection showed significantly higher CD40L, IFN-gamma and FasL mRNA expression than biopsies without rejection. The median values of mRNA expression in biopsies with and without rejection were 0.116 and zero for CD40L (P<0.003), 0.080 and zero for IFN-gamma (P<0.0009), and 0.156 and zero for FasL (P<0.002), respectively. In addition, the levels of IFN-gamma mRNA were significantly increased 7 to 15 days before the appearance of histological evidence of rejection (median of 0.086 in pre-rejection biopsies), i.e., they presented a predictive value. This study provides further evidence of heightened expression of immune activation genes during rejection and shows that some of these markers may present predictive value for the occurrence of acute rejection.


Assuntos
Humanos , Adulto , Endocárdio/metabolismo , Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Miocárdio/metabolismo , Proteínas/metabolismo , RNA Mensageiro/análise , Biópsia , Ligante de CD40/genética , Ligante de CD40/metabolismo , Endocárdio/patologia , Expressão Gênica , Interferon gama/genética , Interferon gama/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Miocárdio/patologia , Valor Preditivo dos Testes , Proteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Homólogo
11.
Braz J Med Biol Res ; 34(6): 779-84, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11378668

RESUMO

The purpose of the present study was to investigate the expression (mRNA) of CD40 ligand (CD40L), interferon-gamma (IFN-gamma) and Fas ligand (FasL) genes in human cardiac allografts in relation to the occurrence of acute cardiac allograft rejection as well as its possible value in predicting acute rejection. The mRNA levels were determined by a semiquantitative reverse transcriptase-polymerase chain reaction method in 39 samples of endomyocardial biopsies obtained from 10 adult cardiac transplant recipients within the first six months after transplantation. Biopsies with ongoing acute rejection showed significantly higher CD40L, IFN-gamma and FasL mRNA expression than biopsies without rejection. The median values of mRNA expression in biopsies with and without rejection were 0.116 and zero for CD40L (P<0.003), 0.080 and zero for IFN-gamma (P<0.0009), and 0.156 and zero for FasL (P<0.002), respectively. In addition, the levels of IFN-gamma mRNA were significantly increased 7 to 15 days before the appearance of histological evidence of rejection (median of 0.086 in pre-rejection biopsies), i.e., they presented a predictive value. This study provides further evidence of heightened expression of immune activation genes during rejection and shows that some of these markers may present predictive value for the occurrence of acute rejection.


Assuntos
Ligante de CD40/metabolismo , Endocárdio/metabolismo , Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Interferon gama/metabolismo , Glicoproteínas de Membrana/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Doença Aguda , Adulto , Biópsia , Ligante de CD40/genética , Endocárdio/patologia , Proteína Ligante Fas , Expressão Gênica , Humanos , Interferon gama/genética , Glicoproteínas de Membrana/genética , Miocárdio/patologia , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Homólogo
12.
J Heart Lung Transplant ; 20(5): 534-43, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11343980

RESUMO

BACKGROUND: Heart transplantation has been an option for the treatment of chagasic (C) cardiomyopathy despite difficulties concerning the control of rejection and reactivation. The parasite-host interaction under the influence of immunosuppressive therapy may affect the immunological response to the graft in a pattern different from that in non-chagasic (NC) patients. The aim of this study was to compare the major histopathological features in heart transplantation in C and NC patients. METHODS: We studied 293 endomyocardial biopsies from two groups of heart transplanted patients, including 18 C and 15 NC. Both groups had identical surgical and clinical procedure except immunosuppressive therapy was lower in C patients. The histopathological parameters evaluated were the Quilty effect, rejection, C myocarditis reactivation, fibrosis, hypertrophy, and ischemia. In addition, lymphocytic cellular infiltration of myocarditis due to rejection or reactivation was immunophenotyped in the biopsies of both groups with rejection grades 3 to 4, in biopsies with signs of reactivation, and in fragments of the receptor heart with chronic C myocarditis. A search for Trypanosoma cruzi was performed in all biopsies in the C group in which lymphocyte immunophenotyping was done. We used immunofluorescence and confocal microscopy. RESULTS: The Quilty effect was present in 23% of the biopsies, involving 69.7% of the patients without a significant difference between groups (p = 0.509). Rejection was frequently observed in biopsies with the Quilty effect and the effect often recurred in the same patient. Rejection grades 3 to 4 was more frequent in the C group (p = 0.023). There were 5 episodes of Chagas' disease reactivation with myocarditis in 2 cases. The mean numbers of CD8+ and CD4+ T cells, and the CD4+-to-CD8+ ratio were similar for rejection in both groups (p > 0.05), while the CD4+-to-CD8+ ratio was significantly lower in chronic C myocarditis compared to rejection in the C group (p = 0.043). There was no significant difference in ischemic damage or interstitial fibrosis in the groups but there was a higher frequency of hypertrophy in the NC group (p = 0.007). CONCLUSIONS: The histopathological features of heart transplantation in C patients did not differ from that in NC patients in regard to the Quilty effect, development of myocardial fibrosis and ischemia. However, the higher involvement of the C group for rejection grades 3 to 4 suggested higher susceptibility to this event. The similarity of the lymphocytic cellular composition for rejection in both groups indicates that C patients respond to immunological stimulus in a similar pattern as NC patients.


Assuntos
Cardiomiopatia Chagásica/patologia , Endocárdio/patologia , Transplante de Coração , Miocárdio/patologia , Adolescente , Adulto , Biópsia , Cardiomegalia/etiologia , Cardiomiopatia Chagásica/cirurgia , Endocárdio/química , Feminino , Imunofluorescência , Rejeição de Enxerto/etiologia , Humanos , Isquemia/etiologia , Doenças Pulmonares Intersticiais/etiologia , Masculino , Pessoa de Meia-Idade , Miocardite/metabolismo , Miocárdio/química , Recidiva , Vasculite/etiologia
13.
Hum Immunol ; 62(4): 342-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11295466

RESUMO

T-cell immune response cDNA 7 (TIRC7) is a recently described T-cell costimulatory molecule that exhibits a central role in T-cell activation in vitro and in vivo. The present study was undertaken to investigate association between intragraft and peripheral blood mononuclear cell (PBMC) TIRC7 mRNA levels and cardiac allograft rejection in humans. TIRC7 gene expression levels were determined by a quantitative-competitive reverse transcriptase-polymerase chain reaction (QC-RT-PCR) in endomyocardial biopsies and in PBMC from cardiac transplant recipients. Biopsies collected during rejection or up to 15 days before rejection showed heightened TIRC7 mRNA expression in comparison with biopsies without rejection. All prerejection and rejection biopsies showed TIRC7 mRNA upregulation, while this was present in only 30% of the biopsies without rejection. Regarding TIRC7 mRNA in PBMC, transplant recipients showed lower levels than healthy individuals and, in contrast to the results obtained in biopsies, the levels were lower during rejection than in rejection-free periods. In summary, TIRC7 mRNA expression levels increase in biopsies and decrease in peripheral blood during acute cardiac rejection. We conclude that intragraft detection of TIRC7 transcripts is a useful tool not only for the diagnosis but also for the prediction of acute heart allograft rejection episodes.


Assuntos
Expressão Gênica , Rejeição de Enxerto/diagnóstico , Transplante de Coração/imunologia , Leucócitos Mononucleares/imunologia , Proteínas de Membrana/genética , Miocárdio/imunologia , Subunidades Proteicas , ATPases Vacuolares Próton-Translocadoras , Rejeição de Enxerto/imunologia , Nível de Saúde , Humanos , Miocárdio/patologia , RNA Mensageiro , Transplante Homólogo/imunologia
15.
Arq Bras Cardiol ; 75(3): 243-8, 2000 Sep.
Artigo em Inglês, Português | MEDLINE | ID: mdl-11018810

RESUMO

Total generalized lipodystrophy (Berardinelli - Seip Syndrome) is a rare hereditary disease characterized by insulin-resistant diabetes mellitus and a small quantity of adipose tissue and is of unknown origin. Common cardiovascular alterations related to this syndrome are cardiac hypertrophy and arterial hypertension. This article reports a case of Berardinelli - Seip syndrome and reviews the literature with special emphasis on the cardiovascular manifestations of this syndrome.


Assuntos
Cardiomegalia/complicações , Diabetes Mellitus Lipoatrófica/complicações , Cardiomegalia/diagnóstico por imagem , Feminino , Humanos , Resistência à Insulina , Radiografia , Ultrassonografia
18.
Braz J Med Biol Res ; 32(4): 413-20, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10347803

RESUMO

Heart transplantation is associated with rapid bone loss and an increased prevalence and incidence of fractures. The aim of the present study was to compare the bone mineral density (BMD) of 30 heart transplant (HT) recipients to that of 31 chronic heart failure (CHF) patients waiting for transplantation and to determine their biochemical markers of bone resorption and hormone levels. The BMD of lumbar spine and proximal femur was determined by dual-energy X-ray absorptiometry. Anteroposterior and lateral radiographs of the thoracic and lumbar spine were also obtained. The mean age of the two groups did not differ significantly. Mean time of transplantation was 25.4 +/- 21.1 months (6 to 88 months). Except for the albumin levels, which were significantly higher, and magnesium levels, which were significantly lower in HT patients when compared to CHF patients, all other biochemical parameters and hormone levels were within the normal range and similar in the two groups. Both groups had lower BMD of the spine and proximal femur compared to young healthy adults. However, the mean BMD of HT patients was significantly lower than in CHF patients at all sites studied. Bone mass did not correlate with time after transplantation or cumulative dose of cyclosporine A. There was a negative correlation between BMD and the cumulative dose of prednisone. These data suggest that bone loss occurs in HT patients mainly due to the use of corticosteroids and that in 30% of the patients it can be present before transplantation. It seems that cyclosporine A may also play a role in this loss.


Assuntos
Densidade Óssea , Transplante de Coração , Corticosteroides/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Cardiomiopatia Chagásica/cirurgia , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/cirurgia , Osteoporose , Período Pós-Operatório
19.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;32(4): 413-20, Apr. 1999. tab
Artigo em Inglês | LILACS | ID: lil-231731

RESUMO

Heart transplantation is associated with rapid bone loss and an increased prevalence and incidence of fractures. The aim of the present study was to compare the bone mineral density (BMD) of 30 heart transplant (HT) recipients to that of 31 chronic heart failure (CHF) patients waiting for transplantation and to determine their biochemical markers of bone resorption and hormone levels. The BMD of lumbar spine and proximal femur was determined by dual-energy X-ray absorptiometry. Anteroposterior and lateral radiographs of the thoracic and lumbar spine were also obtained. The mean age of the two groups did not differ significantly. Mean time of transplantation was 25.4 + ou - 21.1 months (6 to 88 months). Except for the albumin levels, which were significantly higher, and magnesium levels, which were significantly lower in HT patients when compared to CHF patients, all other biochemical parameters and hormone levels were within the normal range and similar in the two groups. Both groups had lower BMD of the spine and proximal femur compared to young healthy adults. However, the mean BMD of HT patients was significantly lower than in CHF patients at all sites studied. Bone mass did not correlate with time after transplantation or cumulative dose of cyclosporine A. There was a negative correlation between BMD and the cumulative dose of prednisone. These data suggest that bone loss occurs in HT patients mainly due to the use of corticosteroids and that in 30 per cent of the patients it can be present before transplantation. It seems that cyclosporine A may also play a role in this loss.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Densidade Óssea , Transplante de Coração , Corticosteroides/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Cardiomiopatia Chagásica/cirurgia , Insuficiência Cardíaca/cirurgia , Isquemia Miocárdica/cirurgia , Osteoporose , Período Pós-Operatório
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