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2.
Am J Med ; 110 Suppl 7A: 47S-62S, 2001 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-11334776

RESUMO

Clinical trials of beta blockers in heart failure have generally required that patients be receiving optimal drug therapy before randomization to the study medication. Therefore, because beta blockers are used in addition to conventional drug therapy, review of the standard drug therapy of mild-to-moderate heart failure before the advent of beta blockade is essential to understanding the role of beta blockers in the treatment of heart failure. The conventional medical management of systolic heart failure includes angiotensin-converting enzyme (ACE) inhibitors, which should be used as first-line therapy; diuretics, for the management of body fluid-volume excess; digoxin; and some other vasodilators. These therapies have been evaluated in large-scale, randomized, controlled trials. ACE inhibitors have been shown to significantly attenuate disease progression and improve outcome (ie, morbidity and mortality) in patients with mild-to-moderate systolic heart failure. Controversial or unproven therapies include nonglycoside inotropic agents, angiotensin II receptor antagonists, antiarrhythmic agents, anticoagulants, and calcium channel blockers. The pharmacologic management of diastolic heart failure is largely empirical and is directed at reducing symptoms. Symptoms caused by increased ventricular filling pressures may be treated with diuretics and long-acting nitrates. Some calcium channel blockers and most beta blockers prolong diastolic filling time by slowing heart rate, thereby potentially improving the symptoms of diastolic heart failure. Calcium antagonists, beta blockers, diuretics, and ACE inhibitors may also promote regression of left ventricular hypertrophy and thus improve ventricular compliance, possibly preventing the development of diastolic dysfunction. Because randomized controlled trials of diastolic heart failure are lacking, this review focuses on the conventional management of mild-to-moderate systolic heart failure before the advent of beta blockade.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Hipertensão/tratamento farmacológico , Angiotensina II/metabolismo , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Antiarrítmicos/uso terapêutico , Anticoagulantes/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Ensaios Clínicos como Assunto , Diuréticos/uso terapêutico , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/terapia , Humanos , Hipertensão/complicações , Dinitrato de Isossorbida/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Vasodilatadores/uso terapêutico
3.
N Engl J Med ; 343(4): 246-53, 2000 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10911006

RESUMO

BACKGROUND: Intravenous infusion of nesiritide, a brain (B-type) natriuretic peptide, has beneficial hemodynamic effects in patients with decompensated congestive heart failure. We investigated the clinical use of nesiritide in such patients. METHODS: Patients hospitalized because of symptomatic congestive heart failure were enrolled in either an efficacy trial or a comparative trial. In the efficacy trial, which required the placement of a Swan-Ganz catheter, 127 patients with a pulmonary-capillary wedge pressure of 18 mm Hg or higher and a cardiac index of 2.7 liters per minute per square meter of body-surface area or less were randomly assigned to double-blind treatment with placebo or nesiritide (infused at a rate of 0.015 or 0.030 microg per kilogram of body weight per minute) for six hours. In the comparative trial, which did not require hemodynamic monitoring, 305 patients were randomly assigned to open-label therapy with standard agents or nesiritide for up to seven days. RESULTS: In the efficacy trial, at six hours, nesiritide infusion at rates of 0.015 and 0.030 microg per kilogram per minute decreased pulmonary-capillary wedge pressure by 6.0 and 9.6 mm Hg, respectively (as compared with an increase of 2.0 mm Hg with placebo, P<0.001), resulted in improvements in global clinical status in 60 percent and 67 percent of the patients (as compared with 14 percent of those receiving placebo, P<0.001), reduced dyspnea in 57 percent and 53 percent of the patients (as compared with 12 percent of those receiving placebo, P<0.001), and reduced fatigue in 32 percent and 38 percent of the patients (as compared with 5 percent of those receiving placebo, P<0.001). In the comparative trial, the improvements in global clinical status, dyspnea, and fatigue were sustained with nesiritide therapy for up to seven days and were similar to those observed with standard intravenous therapy for heart failure. The most common side effect was dose-related hypotension, which was usually asymptomatic. CONCLUSIONS: In patients hospitalized with decompensated congestive heart failure, nesiritide improves hemodynamic function and clinical status. Nesiritide is useful for the treatment of decompensated congestive heart failure.


Assuntos
Fator Natriurético Atrial/uso terapêutico , Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Fator Natriurético Atrial/efeitos adversos , Fator Natriurético Atrial/farmacologia , Cardiotônicos/efeitos adversos , Cardiotônicos/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dispneia/tratamento farmacológico , Fadiga/tratamento farmacológico , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipotensão/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico , Pressão Propulsora Pulmonar/efeitos dos fármacos , Vasodilatadores/uso terapêutico
4.
Circ Res ; 86(8): 834-40, 2000 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10785504

RESUMO

The beta(2)-adrenergic receptor (beta(2)AR) exists in multiple polymorphic forms with different characteristics. Their relevance to heart failure (HF) physiology is unknown. Cardiopulmonary exercise testing was performed on 232 compensated HF patients with a defined beta(2)AR genotype. Patients with the uncommon Ile164 polymorphism had a lower peak VO(2) (15.0+/-0.9 mL. kg(-1). min(-1)) than did patients with Thr164 (17.9+/-0.9 mL. kg(-1). min(-1), P<0.0001). The percentage achieved of predicted peak VO(2) was also lower in patients with Ile164 (62. 3+/-4.5% versus 71.5+/-5.1%, P=0.045). The relative risk of a patient having a VO(2)

Assuntos
Exercício Físico , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/fisiopatologia , Polimorfismo Genético , Receptores Adrenérgicos beta 2/genética , Alelos , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade
5.
Cardiovasc Res ; 45(4): 883-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10728414

RESUMO

OBJECTIVE: Left ventricular assist device support mechanically unloads the failing ventricle with resultant improvement in cardiac geometry and function in patients with end-stage heart failure. Activation of the G alpha q signaling pathway, including protein kinase C, appears to be involved in the progression of heart failure. Similarly down-regulation of Ca2+ cycling proteins may contribute to contractile depression in this clinical syndrome. Thus we examined whether protein kinase C activation and decreased Ca2+ cycling protein levels could be reversed by left ventricular assist device support. METHODS: Left ventricular myocardial specimens were obtained from seven patients during placement of left ventricular assist device and heart transplantation. We examined changes in protein levels of G alpha q, phospholipase C beta 1, regulators of G protein signaling (RGS), sarcoplasmic reticulum Ca2+ ATPase, phospholamban and translocation of protein kinase C isoforms (alpha, beta 1, and beta 2). RESULTS: The paired pre- and post-left ventricular assist device samples revealed that RGS2, a selective inhibitor of G alpha q, was decreased (P < 0.01), while the status of G alpha q, phospholipase C beta 1, RGS3 and RGS4 were unchanged after left ventricular assist device implantation. Translocation of protein kinase C isoforms remained unchanged. Left ventricular assist device support increased sarcoplasmic reticulum Ca2+ ATPase protein level (P < 0.01), while phospholamban abundance was unchanged. CONCLUSIONS: We conclude that altered protein expression and stoichiometry of the major cardiomyocyte Ca2+ cycling proteins rather than reduced phospholipase C beta 1 activation may contribute to improved mechanical function produced by left ventricular assist device support in human heart failure.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Insuficiência Cardíaca/metabolismo , Coração Auxiliar , Miocárdio/metabolismo , Proteína Quinase C/metabolismo , Proteínas RGS/metabolismo , Adolescente , Adulto , Proteínas de Ligação ao Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/terapia , Humanos , Immunoblotting , Isoenzimas/metabolismo , Masculino , Pessoa de Meia-Idade , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/enzimologia , Transdução de Sinais/fisiologia , Estatísticas não Paramétricas
6.
J Holist Nurs ; 17(2): 117-38, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10633647

RESUMO

Persons with heart failure face a myriad of challenges due to the physical limitations imposed by the chronic illness. Despite these changes, each person must continue to face the developmental challenges of adulthood. This exploratory study was conducted to examine the impact that this chronic illness has on the developmental processes of adults. Methods triangulation was used to examine the content of unprompted, written goals and the results of surveys of life satisfaction and mood states of 138 persons with heart failure. Younger adults had higher anger, depression, and anxiety scores than older or middle-aged adults and had lower scores of life satisfaction. This may reflect the emotional reaction to the realization that their lives may be shortened by this chronic illness. Analysis of their goals reflected the developmental challenges described by Erikson. Despite severe physical limitations, these individuals demonstrated growth and achievement of developmental tasks by transcending usual time lines.


Assuntos
Insuficiência Cardíaca/psicologia , Desenvolvimento Humano , Qualidade de Vida , Adulto , Afeto , Feminino , Objetivos , Insuficiência Cardíaca/enfermagem , Enfermagem Holística , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Metodológica em Enfermagem , Satisfação Pessoal , Estudos Prospectivos
7.
J Clin Invest ; 102(8): 1534-9, 1998 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9788966

RESUMO

The beta2-adrenergic receptor (beta2AR), an important modulator of cardiac inotropy and chronotropy, has significant genetic heterogeneity in the population. Because dysfunctional betaARs play a role in the pathogenesis of the failing ventricle, we tested the hypothesis that beta2AR polymorphisms alter the outcome of congestive heart failure. 259 patients with NYHA functional class II-IV heart failure due to ischemic or dilated cardiomyopathy were genotyped and prospectively followed, with the endpoint defined as death or cardiac transplantation. The allele frequencies between this group and those of 212 healthy controls also were compared and did not differ between the groups. However, those with the Ile164 polymorphism displayed a striking difference in survival with a relative risk of death or cardiac transplant of 4.81 (P < 0.001) compared with those with the wild-type Thr at this position. Age, race, gender, functional class, etiology, ejection fraction, and medication use did not differ between these individuals and those with the wild-type beta2AR, and thus the beta2AR genotype at position 164 was the only clear distinguishing feature between the two groups. The 1-yr survival for Ile164 patients was 42% compared with 76% for patients harboring wild-type beta2AR. In contrast, polymorphisms at amino acid positions 16 (Arg or Gly) or 27 (Gln or Glu), which also alter receptor phenotype, did not appear to have an influence on the course of heart failure. Taken together with cell-based and transgenic mouse results, this study establishes a paradigm whereby genetic variants of key signaling elements can have pathophysiologic consequences within the context of a disease. Furthermore, patients with the Ile164 polymorphism and heart failure may be candidates for earlier aggressive intervention or cardiac transplantation.


Assuntos
Insuficiência Cardíaca/genética , Isoleucina/genética , Polimorfismo Genético , Receptores Adrenérgicos beta 2/genética , Adulto , Alelos , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/terapia , Feminino , Frequência do Gene , Genótipo , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Isquemia Miocárdica/genética , Isquemia Miocárdica/terapia , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
8.
J Heart Lung Transplant ; 17(7): 698-702, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9703235

RESUMO

BACKGROUND: Female heart transplant recipients are able to carry pregnancies successfully. This study evaluates the effect of subsequent pregnancies on newborn and maternal outcomes and graft survival. METHODS: Subjects were identified through a previously reported multicenter study, case reports from literature review, and recipients entered in the National Transplantation Pregnancy Registry. A retrospective analysis was completed of 35 heart transplant recipients with first pregnancies (FP) and 12 who had one or two additional pregnancies (P>1). Newborns were assessed for gestational age, neonatal birth weight, and complications. Maternal data included pregnancy outcome, peripartum complications, including infection and rejection, current graft function, and recipient survival. RESULTS: Forty-seven pregnancies (35 FP and 12 P>1) from 35 heart transplant recipients were studied. FP outcomes included 26 live births (one set of twins), four miscarriages, and six therapeutic abortions, whereas P>1 outcomes included 11 live births (one set of twins), and two miscarriages. There was no significant difference between mean birth weights (2353+/-986 gm vs 2588+/-521 g, P>1 vs FP; mean+/-SD; p=NS) or prematurity incidence (<37 weeks; 50% vs 40%; p=NS) for the live-born infants. Compared with the FP group, there was a trend toward increased neonatal complications in P>1 (40% vs 12%; p=NS). Complications were significantly more common in premature newborns compared with full-term newborns (33% vs 5%; p < 0.05). No structural malformations were identified in the live-born infants. Maternal complication rates were the same in both groups (40%). Of 28 recipients available for follow-up, the maternal survival rate was 75% for the FP group and 89% for the P> group. Mean rejection rate per year was slightly increased after pregnancy in the P>1 group. Surviving recipients had similar graft function by echocardiographic left ventricular ejection fraction. CONCLUSIONS: Post-heart transplantation pregnancies often have successful outcomes, but there is a high incidence of prematurity and low birth weight. Subsequent pregnancies do not seem to significantly increase the incidence of complications in either the newborn or mother or increase graft rejection or failure. Larger studies of posttransplantation pregnancies may provide more definitive information.


Assuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Coração/fisiologia , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
9.
J Mol Cell Cardiol ; 30(3): 443-51, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9515022

RESUMO

Annexins are a unique family of membrane-associated, Ca2+ and phospholipid-binding proteins found in various tissues. Among the 12 isoforms, Annexin II, V and VI exist in heart tissue in the highest amounts. Annexin VI has been shown to affect intracellular Ca2+ cycling and contractility in isolated cardiomyocytes. Annexin V is present in both cardiomyocytes and non-myocyte cell types in the heart and may play a role in the regulation of cellular ion fluxes, organization and secretion, while the cardiac effects of annexin II are unclear. To identify changes in annexin II, V and VI isoforms that might occur in human heart failure, we measured mRNA and protein levels of these three annexins in transplanted left ventricular tissue of 12 patients with end-stage congestive heart failure due to coronary artery disease (CAD, n=6) or idiopathic dilated cardiomyopathy (DCM, n=6) who underwent cardiac transplantation. Normal heart tissue (C, n=6) was used as a control. Northern blot analyses showed a significant decrease (61%) in annexin VI mRNA levels in heart failure patients compared with controls (1.08+/-0.16 v 2.79+/-0.20 A.U.C. unit, determined by laser densitometry, mean+/-s.e.). In contrast, we found a 67% increase (2. 32+/-0.27 v 3.88+/-0.29) in annexin II mRNA levels and a two-fold increase (1.00+/-0.24 v 2.21+/-0.29) in annexin V mRNA levels in cardiomyopathic hearts as compared to normal hearts. Western blot analyses demonstrated a corresponding decrease (46.1%) in annexin VI protein levels in the heart failure group as compared to controls (2. 63+/-0.22 v 4.88+/-0.52), while annexin II protein levels showed a significant 40.7% increase in patients with heart failure compared to those in normal hearts (5.08+/-0.67 v 3.61+/-0.32). Annexin V protein levels were also significantly increased (45%) in heart failure patients compared with normal (2.14+/-0.19 v 1.48+/-0.11). No difference in either annexins II, V or VI mRNA and protein levels were found between CAD and DCM patients. We conclude that human end-stage heart failure is associated with a down regulation of annexin VI and up regulation of annexin II and V proteins. Coordinate changes were observed in steady-state mRNA levels. These results suggest that these annexin isoforms may contribute to the regulation of intracellular Ca2+ homeostasis in the cardiomyopathic heart.


Assuntos
Anexinas/genética , Anexinas/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adulto , Anexina A2/genética , Anexina A2/metabolismo , Anexina A5/genética , Anexina A5/metabolismo , Anexina A6/genética , Anexina A6/metabolismo , Cálcio/metabolismo , Estudos de Casos e Controles , Regulação para Baixo , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/metabolismo , Homeostase , Humanos , Líquido Intracelular/metabolismo , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Regulação para Cima
10.
Am J Med Sci ; 314(3): 173-84, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9298043

RESUMO

Cardiac transplantation has become an accepted treatment for selected patients with end-stage heart failure. Despite a successful transplant, denervated transplanted hearts respond differently to cardiac drugs than nontransplanted hearts. The treatments for bradycardia, tachycardia, and hypotension are different than for nontransplanted hearts. Despite the improvement in long-term survival, a number of complications may occur posttransplantation. These complications include, allograft rejection, infection, allograft coronary artery disease, and malignancy. Additionally, posttransplant patients may have complications from the immunosuppressive agents cyclosporine, prednisione, and azathioprine. Such complications include drug interactions with commonly prescribed medications, hypertension, hyperlipidemia, osteoporosis, and gastrointestinal complications. The purpose of this article is to discuss the management of the cardiac transplant recipient as it relates to the aforementioned complications. Management of the cardiac transplantation patient by the primary care physician will also be discussed, including indications for consultation by the primary care physician with the transplant center.


Assuntos
Cardiologia , Medicina de Família e Comunidade , Transplante de Coração/efeitos adversos , Papel do Médico , Bradicardia/tratamento farmacológico , Administração de Caso , Doença das Coronárias/diagnóstico , Doença das Coronárias/terapia , Feminino , Gastroenteropatias/etiologia , Rejeição de Enxerto , Humanos , Hiperlipidemias/etiologia , Hipertensão/etiologia , Hipotensão/terapia , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Masculino , Osteoporose/etiologia , Gravidez , Complicações Cardiovasculares na Gravidez , Taquicardia/tratamento farmacológico
11.
Clin Transplant ; 10(5): 437-43, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8930458

RESUMO

Allograft rejection remains a major cause of morbidity and mortality. Cyclophosphamide, a nitrogen mustard, is a potent immunosuppressive agent with effects on both T- and B-lymphocytes, and thus may be effective in preventing further cellular and/or humoral rejection in cardiac transplant recipients with recurrent or recalcitrant rejection. We retrospectively reviewed the records of 320 surviving cardiac transplant recipients. Cyclophosphamide was substituted for azathioprine in 28 patients because of frequent allograft rejection. We then reviewed the rejection history of these 28 patients, specifically looking at rejection frequency, type (cellular, vascular or mixed), and treatment. Cyclophosphamide was substituted for azathioprine at an average of 8.4 +/- 2.8 months after transplantation. Despite a 56.0% reduction in prednisone dose (p < 0.001), at least a threefold reduction in rejection frequency (p < 0.001) was observed, while cyclosporine levels were unchanged. Twenty-eight percent of the patients did not experience even mild rejection after beginning therapy with cyclophosphamide, 55% had 1 or 2 subsequent mild or moderate rejection episodes, and only 17% had more than two subsequent episodes of mild or moderate rejection. Overall, the number of treated rejection episodes decreased from 0.37 episodes per patient month with azathioprine to 0.10 episodes per patient month on therapy with cyclophosphamide. Separating the patients into two groups based on the predominant rejection type (cellular vs. vascular) occurring at the time of cyclophosphamide substitution revealed a similar reduction in cellular and vascular rejection in each respective group. While white blood cell count decreased by 16%, cyclophosphamide was not discontinued in any patient due to leukopenia, and no change was noted in hematocrit. Cyclophosphamide appears to be safe and effective in maintenance immunosuppression and may reduce rejection frequency in some patients with frequently occurring allograft rejection without necessitating the augmentation of either corticosteroids or cyclosporine.


Assuntos
Ciclofosfamida/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Transplante de Coração , Imunossupressores/uso terapêutico , Azatioprina/uso terapêutico , Feminino , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/tratamento farmacológico , Transplante de Coração/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos
12.
Curr Opin Cardiol ; 11(3): 237-44, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8835865

RESUMO

Congestive heart failure is the final common pathway of diverse etiologies that result in impaired systolic and diastolic function, deleterious activation of neurohumoral pathways, and high morbidity and mortality. Many studies published in 1995 significantly added to our understanding of the pathophysiologies of heart failure at the cellular level. Because a common accompaniment to all forms of low output heart failure are hypertrophy and contractile dysfunction of the cardiomyocyte, applications of the techniques of molecular and cell biology to animal models that demonstrate this phenomenon are providing new insights into the mechanisms responsible for this important clinical problem. In the past year, critical information was derived from animal models that mimic human cardiac hypertrophy and failure. Likewise, genetically engineered mice in which a gene product of interest is overexpressed or eliminated provided critical information, in particular regarding the roles of phospholamban and beta-adrenergic receptor kinase 1 in mediating the contractile responses of the heart to beta-adrenergic stimulation. Furthermore, study of human myocardial tissue from patients with end-stage cardiomyopathy continues to provide insight into the diverse etiologies of heart failure. The recent applications of the techniques of molecular and cell biology to this clinical problem are likely to accelerate our understanding of the complex mechanisms responsible for this syndrome.


Assuntos
Insuficiência Cardíaca/etiologia , Miocárdio/patologia , Potenciais de Ação , Adenosina Trifosfatases/metabolismo , Animais , Cálcio/análise , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Cátions/metabolismo , Gatos , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Citoesqueleto/metabolismo , Citosol/química , Cães , Expressão Gênica , Cobaias , Humanos , Camundongos , Fibras Musculares Esqueléticas/ultraestrutura , Miocárdio/metabolismo , Receptores Adrenérgicos beta/fisiologia , Sódio/análise , Quinases de Receptores Adrenérgicos beta
13.
Circulation ; 93(1): 111-9, 1996 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8616917

RESUMO

BACKGROUND: Immunologic mechanisms that mediate myocardial cell injury during rejection are not fully understood. We therefore investigated whether cells that infiltrate rejecting cardiac allografts are capable of directly injuring myocytes and whether this injury resembles that produced by cytotoxic T lymphocytes (CTLs) that are generated in a mixed lymphocyte reaction (MLR). METHODS AND RESULTS: Heart-infiltrating cells (HICs) were isolated from murine heterotopic BALB/c cardiac allografts undergoing rejection 6 to 8 days after transplantation into C57BL/6 mice. An in vitro model system of cultured adult murine ventricular myocytes was developed to facilitate investigation of cell-mediated myocyte injury. Isolated adult myocytes were incubated with either HICs or MLR effector cells, and myocyte death was quantified by counting the number of rod-shaped myocytes excluding trypan blue. The frequency of donor-reactive CTLs was similar in the HIC and MLR populations, as assessed by limiting dilution analysis. However, HICs were less efficient at killing donor-strain myocytes than were MLR cells. CTL-mediated cell lysis occurred by 6 hours, whereas myocyte injury produced by HICs was more gradual, with considerable cytotoxicity occurring between 12 and 24 hours. Furthermore, whereas MLR cells lysed only donor-strain myocytes, HIC lysed donor, third-party, and syngeneic myocytes. Treatment of MLR cells and HICs with anti-CD8 antibody plus complement produced a much greater inhibition of MLR cytotoxicity than of HIC cytotoxicity. CONCLUSIONS: These data demonstrate that only a small component of myocyte injury mediated by allograft-infiltrating cells can be ascribed to CTLs within the infiltrating cell population. These findings suggest that cell types associated with a delayed-type hypersensitivity response, as well as CTLs, cause myocyte injury during cardiac rejection.


Assuntos
Rejeição de Enxerto/patologia , Transplante de Coração , Ventrículos do Coração/patologia , Animais , Antígenos CD8/imunologia , Morte Celular , Células Cultivadas , Técnicas de Cocultura , Citotoxicidade Imunológica , Feminino , Rejeição de Enxerto/imunologia , Ventrículos do Coração/embriologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Gravidez , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Transplante Homólogo
15.
Transplantation ; 58(6): 645-9, 1994 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-7940682

RESUMO

Humoral immune responses have been implicated in the pathogenesis of vascular rejection, allograft coronary artery disease, and sensitization to OKT3. Because cyclophosphamide (CP) is a potent suppressor of humoral immunity, we postulated that substituting cyclophosphamide for azathioprine (AZA) would be associated with a decrease in acute vascular rejection and sensitization to OKT3 in cardiac transplant recipients also receiving cyclosporine, corticosteroids, and perioperative OKT3. We prospectively randomized 119 patients to receive azathioprine (n = 61) or cyclophosphamide (n = 58) from the time of transplantation. Dosage was adjusted to target white blood cell (WBC) counts. At six weeks posttransplantation, cyclophosphamide was converted to azathioprine. Patients were followed for a mean of 321 +/- 16 days. At four weeks WBC (1000/mm3) was 9.2 +/- 0.4 (SEM) in the AZA group and 9.7 +/- 0.6 for the CP group (P = 0.4). No differences were noted between the CP and AZA groups in mean cellular grades of rejection (1.8 +/- 0.1 vs. 1.7 +/- 0.1), mean vascular grades of rejection (2.0 +/- 0.1 vs. 1.8 +/- 0.1), early treated rejection episodes (1.9 +/- 0.1 vs. 2.2 +/- 0.1) days to first treated cellular rejection (38 +/- 3 vs. 41 +/- 3), or the number of patients manifesting primarily vascular rejection (18 vs. 19). Major infections and survival did not differ between the two groups. Eight patients in the AZA group developed anti-OKT3 antibodies, whereas only one patient in the CP group did (P = 0.04). In the early posttransplant period cyclophosphamide decreases the incidence of sensitization to OKT3 and appears to be as effective as azathioprine in preventing both cellular and vascular rejection.


Assuntos
Azatioprina/uso terapêutico , Ciclofosfamida/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/imunologia , Formação de Anticorpos , Feminino , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto , Humanos , Imunidade , Masculino , Pessoa de Meia-Idade , Muromonab-CD3/administração & dosagem , Muromonab-CD3/imunologia , Pré-Medicação , Estudos Prospectivos , Taxa de Sobrevida
16.
Transplantation ; 57(9): 1337-40, 1994 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8184472

RESUMO

To assess whether children fathered by cardiac transplant recipients are at high risk of teratogenicity, cardiac transplant centers listed with the International Society for Heart and Lung Transplantation were surveyed. Paternities after transplantation by heart (n = 35) and heart-lung (n = 1) allograft recipients have resulted in 42 pregnancies (children's age 3.3 +/- 0.3 years). The fathers' age at conception was < 45 years in 40 (95%) and > 45 years in 2 (5%). Most fathers (86%) were enjoying an active and healthy lifestyle at the time of conception; one (2%) was on dialysis and listed for kidney transplantation due to nephrotic syndrome, 1 (2%) had asthma, 4 (10%) had allograft coronary disease (1 died while waiting for second heart transplant when the child was 2 months old), and 2 (5%) were retransplanted after the pregnancies. Immunosuppressive regimens were reported for 37 paternities; drug protocols at the time of conception were as follows: 25 (60%) CsA/prednisone/AZA, 6 (14%) CsA/prednisone, 4 (10%) CsA/AZA, and 2 (5%) AZA/prednisone. Twenty-six (62%) had received treatment for rejection episodes before conception; seven (17%) had received treatment for rejections since conception. Of the 42 children fathered by these recipients, 3 (7%) were preterm, 1 (2%) had a cleft palate and lip that have subsequently been corrected, 1 (2%) died from interruption of umbilical cord circulation at 24 weeks, and 1 (2%) whose father had familial cardiomyopathy was born with a cardiomyopathy that improved with time. Although the numbers are small, the available data suggest that paternity by cardiac transplant recipients may be safe.


Assuntos
Fertilidade/fisiologia , Transplante de Coração/fisiologia , Transplante de Coração-Pulmão/fisiologia , Adulto , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paternidade , Gravidez/estatística & dados numéricos , Fatores de Risco , Inquéritos e Questionários
17.
Transplantation ; 56(6): 1415-8, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8279012

RESUMO

AZA has been reported to cause liver dysfunction in some recipients of solid organ transplants. To assess the safety and efficacy of cyclophosphamide in maintenance immunosuppression in the setting of AZA-induced liver dysfunction, we retrospectively reviewed the records of 320 surviving cardiac transplant recipients in Utah. Cyclophosphamide was substituted for AZA in 29 patients due to elevated liver enzymes. Patients were switched to cyclophosphamide 689 +/- 104 days after transplantation; total follow-up after initiation of cyclophosphamide was 540 +/- 56 days. The dose of cyclophosphamide after 2 and 6 months of cyclophosphamide therapy was 62 +/- 6 mg/day (0.8 +/- 0.1 mg/kg/day) and 48 +/- 5 mg/day (0.6 +/- 0.1 mg/kg/day), respectively, compared with 233 +/- 20 mg/day (2.9 +/- 0.2 mg/kg/day) of AZA. The substitution of cyclophosphamide for AZA was associated with a significant improvement in liver function tests. Liver enzymes decreased by up to 49% (P = 0.027), while serum bilirubin decreased by 58% (P < 0.001). Rejection frequency did not increase; neither corticosteroid nor CsA dosage was altered significantly after the substitution of cyclophosphamide. Significant bone marrow suppression was not observed; specifically, no significant change in white blood cell count or hematocrit occurred. Complications of treatment with cyclophosphamide were few; only 1 patient discontinued cyclophosphamide because of alopecia. We conclude that cyclophosphamide appears to be safe in maintenance immunosuppression, permitting the discontinuation of AZA in patients with AZA-induced hepatic dysfunction without necessitating the augmentation of either corticosteroids or CsA.


Assuntos
Azatioprina/efeitos adversos , Ciclofosfamida/uso terapêutico , Transplante de Coração , Fígado/efeitos dos fármacos , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Ciclofosfamida/efeitos adversos , Feminino , Transplante de Coração/efeitos adversos , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Fígado/fisiologia , Masculino , Pessoa de Meia-Idade , Segurança
18.
J Heart Lung Transplant ; 12(6 Pt 1): 993-9; discussion 1000, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8312325

RESUMO

To evaluate challenges facing heart transplant recipients who become pregnant, we surveyed 194 heart transplantation centers and reviewed the literature. Thirty-two known pregnancies in heart (n = 29) or heart-lung (n = 3) allograft recipients have resulted in 29 children, including two sets of twins. The method of delivery was most often vaginal (cesarean section rate was 33%), and premature delivery was common (41%). The onset of pregnancy from the time of transplantation was 2.6 +/- 0.3 years, with the age at conception ranging from 19 to 35 years. Hypertension (44%), premature labor (30%), and preeclampsia (22%) were the most frequent maternal complications. Four patients experienced a worsening of ongoing chronic renal insufficiency; four patients experienced infections during pregnancy, and six patients (22%) were successfully treated for rejection episodes during pregnancy by adjustments in standard immunosuppressive agents. No peripartum deaths were reported; three late deaths occurred. Of the 29 children born of heart transplant recipients who became pregnant, no fetal anomalies or neonatal deaths occurred. Prematurity (41%) and low birth weight (17%) were the most common complications. All children are reported in good health at 3.4 +/- 0.4 years of age. Most transplant recipients (59%) were being treated with triple-drug immunosuppression with azathioprine, corticosteroids, and cyclosporine during pregnancy. The most common alteration to immunosuppressive therapy during pregnancy (41%) involved increasing cyclosporine doses caused by decreasing cyclosporine levels during pregnancy. Twenty-two percent of patients underwent empiric lowering of cyclosporine doses during pregnancy; four patients continued with corticosteroid tapering during pregnancy, and four patients increased corticosteroid doses.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Parto Obstétrico , Transplante de Coração , Imunossupressores/administração & dosagem , Complicações na Gravidez , Adulto , Feminino , Transplante de Coração-Pulmão , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez/terapia , Resultado da Gravidez
19.
Obstet Gynecol ; 82(3): 324-7, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8355928

RESUMO

OBJECTIVE: To determine the outcome of pregnancies in cardiac allograft recipients. METHODS: Thirty women who became pregnant after heart transplantation were identified from cases managed personally, questionnaires sent to all cardiac transplant centers, and review of the literature. Mothers were evaluated for evidence of rejection and for obstetric complications. The infants were observed for congenital abnormalities and perinatal morbidity or mortality. RESULTS: Frequent pregnancy complications included chronic hypertension (48%), preeclampsia (24%), and preterm labor (28%). The rate of cesarean delivery was 32%. Six episodes of rejection required treatment, and three late maternal deaths occurred. Among the 27 live births, 17 infants were born after 36 weeks' gestation and ten were preterm, five were small for gestational age, and four had neonatal complications. There were no congenital anomalies. CONCLUSION: Pregnancies in heart transplant recipients present management problems similar to those seen in patients with other allografts and should be considered high risk.


Assuntos
Transplante de Coração , Complicações na Gravidez/terapia , Resultado da Gravidez , Adulto , Feminino , Humanos , Gravidez , Complicações na Gravidez/epidemiologia
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