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1.
Adv Ther ; 41(2): 618-637, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38055186

RESUMO

INTRODUCTION: In the event-driven FREEDOM-EV trial, oral treprostinil delayed clinical worsening in patients with pulmonary arterial hypertension (PAH). Open-label extension studies offer additional data about tolerability, efficacy, and survival, especially for those initially assigned placebo. The aim of the current study was to determine if oral treprostinil changed survival when considering the parent and extension study, if treprostinil provides functional benefits for participants initially assigned to placebo, and if the benefits observed for those treated with treprostinil were durable. METHODS: Both active and placebo participants from FREEDOM-EV could enroll in the FREEDOM-EV open-label extension (OLE) study after experiencing an investigator-assessed clinical worsening event or after parent study closure. All participants in the OLE were offered open-label oral treprostinil. Previously assigned placebo participants titrated to maximally tolerated doses; previously assigned treprostinil participants continued dose titration. We repeated assessments including functional class and 6-min walk distance (6MWD) at 12-week intervals and measured N-terminal pro-brain natriuretic peptide (NT-proBNP) at week 48. Survival was estimated by Kaplan-Meier analysis, and we estimated hazard ratio (HR) using Cox proportional hazards. RESULTS: Of 690 FREEDOM-EV participants, 470 enrolled in the OLE; vital status was available for 89% of initial Freedom-EV participants. When considering the combined parent and open-label data, initial assignment to oral treprostinil reduced mortality (HR 0.64, 95% confidence interval 0.46-0.91, p = 0.013); absolute risk reduction was 9%. Participants randomized to placebo who initiated oral treprostinil after clinical worsening and tolerated treatment through week 48 demonstrated favorable shifts in functional class (p < 0.0001), 6MWD improvements of + 84 m (p < 0.0001), and a reduction in NT-proBNP of - 778 pg/mL (p = 0.02), compared to OLE baseline. Modest trends toward benefit were measured for those initially assigned placebo who did not have clinical worsening, and 132/144 (92%) of treprostinil assigned participants without clinical worsening remained on drug at week 48 in the OLE study. Adverse events were consistent with FREEDOM-EV. CONCLUSION: Initial treprostinil assignment improved survival in the entire data set; those who began treprostinil after a clinical worsening in the placebo arm and tolerated drug to week 48 enjoyed substantial functional gains. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01560637.


Assuntos
Anti-Hipertensivos , Hipertensão Pulmonar , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Resultado do Tratamento , Epoprostenol/efeitos adversos
2.
EBioMedicine ; 100: 104900, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38092579

RESUMO

BACKGROUND: Pulmonary Arterial Hypertension (PAH) is a progressive condition with no cure. Even with pharmacologic advances, survival remains poor. Lung pathology on PAH therapies still shows impressive occlusive arteriolar remodelling and plexiform lesions. Cardiosphere-derived cells (CDCs) are heart-derived progenitor cells exhibiting anti-inflammatory and immunomodulatory effects, are anti -fibrotic, anti-oxidative and anti-apoptotic to potentially impact several aspects of PAH pathobiology. In preclinical trials CDCs reduced right ventricular (RV) systolic pressure, RV hypertrophy, pulmonary arteriolar wall thickness and inflammation. METHODS: The ALPHA study was a Phase 1a/b study in which CDCs were infused into patients with Idiopathic (I)PAH, Heritable (H) HPAH, PAH-connective tissue disease (CTD) and PAH-human immunodeficiency virus (HIV). The study was IRB approved and DSMB monitored. Phase 1a, was an open label study (n = 6). Phase 1b was a double-blind placebo-controlled study (n = 20) in which half received 100 million CDCs (the maximum feasible dose from manufacturing perspective) and half placebo (PLAC) infusions. Right heart catheterization (RHC) and cardiac MR imaging (cMR) were performed at baseline and at 4 months post infusion. Patients were followed over a year. FINDINGS: No short-term clinical safety adverse events (AE) were related to the IP, the primary outcome measure. There were no adverse hemodynamic, gas exchange, rhythm or other clinical events following infusion and in the 1st 23 h monitored in hospital. There were no long-term AEs over 12 months noted, including unrelated limited hospitalizations. No immunologic short or long-term AEs were noted. We examined exploratory outcomes across multiple domains to determine encouraging signals to motivate future advanced phase testing. Phase 1a data showed encouraging observations for both 50 and 100 million CDC doses. Several encouraging findings favouring CDCs (n = 16) compared to placebo (n = 10) were noted. On cMR, the RV end diastolic volume (RVEDV) and index (RVEDVI) decreased with CDCs with a rise in the PLAC group. The 6-min walk distance was increased 2 months post infusion in the CDC group compared with PLAC. With PLAC, diffusing capacity (DLCO) decreased at 4 months but was unchanged with CDCs. Serum creatinine decreased with CDCs at 4 months. Encouraging observations favouring CDCs were also noted for RV fractional area change on echo and RV ejection fraction (RVEF) on cMR at 4 months. No differences were observed for mean pulmonary artery pressures or pulmonary vascular resistance. Review of long-term data to 12 months showed continued decline in DLCO for the PLAC cohort at 6 months with no change through 12 months. By contrast, CDC subjects showed an unchanged DLCO over 12-months. For parameters exhibiting early encouraging exploratory findings in CDC subjects, no further improvement was noted in long-term follow up through 12 months. INTERPRETATION: Intravenous CDCs were safe in both the short and long term in PAH subjects and thus may be safe in larger cohorts, in line with our extensive track record of safety in clinical trials for other conditions. Further, CDCs exhibited encouraging exploratory findings across several domains. Repeat dosing (quarterly, over one year) of intravenous CDCs has been reported to yield highly significant sustained disease-modifying bioactivity in subjects with advanced Duchenne muscular dystrophy. Because only single CDC doses were used here, the findings represent a lower limit estimate of CDC's potential in PAH. Upcoming phase 2 studies would logically use a repeat dosing paradigm. FUNDING: California Institute for Regenerative Medicine (CIRM). Project Number: CLIN2-09444.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Hipertensão Arterial Pulmonar , Humanos , Coração , Volume Sistólico
3.
Front Physiol ; 11: 503, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670075

RESUMO

BACKGROUND: Cardiac Bridging Integrator 1 (cBIN1) is a membrane deformation protein that generates calcium microdomains at cardiomyocyte t-tubules, whose transcription is reduced in heart failure, and is released into blood. cBIN1 score (CS), an inverse index of plasma cBIN1, measures cellular myocardial remodeling. In patients with heart failure with preserved ejection fraction (HFpEF), CS diagnoses ambulatory heart failure and prognosticates hospitalization. The performance of CS has not been tested in patients with heart failure with reduced ejection fraction (HFrEF). METHODS AND RESULTS: CS was determined from plasma of patients recruited in a prospective study. Two comparative cohorts consisted of 158 ambulatory HFrEF patients (left ventricular ejection fraction (LVEF) ≤ 40%, 57 ± 10 years, 80% men) and 115 age and sex matched volunteers with no known history of HF. N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentrations were also analyzed for comparison. CS follows a normal distribution with a median of 0 in the controls, which increases to a median of 1.9 (p < 0.0001) in HFrEF patients. CS correlates with clinically assessed New York Heart Association Class (p = 0.007). During 1-year follow-up, a high CS (≥ 1.9) in patients predicts increased cardiovascular events (43% vs. 26%, p = 0.01, hazard ratio 1.9). Compared to a model with demographics, clinical risk factors, and NT-proBNP, adding CS to the model improved the overall continuous net reclassification improvement (NRI 0.64; 95% CI 0.18-1.10; p = 0.006). Although performance for diagnosis and prognosis was similar to CS, NT-proBNP did not prognosticate between patients whose NT-proBNP values were > 400 pg/ml. CONCLUSION: CS, which is mechanistically distinct from NT-proBNP, successfully differentiates myocardial health between patients with HFrEF and matched controls. A high CS reflects advanced NYHA stage, pathologic cardiac muscle remodeling, and predicts 1-year risk of cardiovascular events in ambulatory HFrEF patients. CS is a marker of myocardial remodeling in HFrEF patients, independent of volume status.

4.
JAMA Cardiol ; 3(12): 1206-1210, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383171

RESUMO

Importance: Transverse tubule remodeling is a hallmark of heart failure. Cardiac bridging integrator 1 (cBIN1) is a circulating membrane scaffolding protein that is essential for transverse tubule health, and its plasma level declines with disease. Objective: To determine if a cBIN1-derived score can serve as a diagnostic biomarker of heart failure with preserved ejection fraction (HFpEF). Design, Setting, and Participants: In this cohort study, the cBIN1 score (CS) was determined from enzyme-linked immunoabsorbent assay-measured plasma cBIN1 concentrations from study participants in an ambulatory heart failure clinic at Cedars-Sinai Medical Center. Consecutive patients with a confirmed diagnosis of heart failure with preserved ejection fraction (HFpEF; defined by a left ventricular ejection fraction ≥50%) were recruited from July 2014 to November 2015 and compared with age-matched and sex-matched healthy volunteers with no known cardiovascular diagnoses and participants with risk factors for heart failure but no known HFpEF. Baseline characteristics and 1-year longitudinal clinical information were obtained through electronic medical records. Data analysis occurred from November 2016 to November 2017. Main Outcomes and Measures: The analysis examined the ability of the CS and N-terminal pro-B-type natriuretic peptide (NT-proBNP) results to differentiate among patients with HFpEF, healthy control participants, and control participants with risk factors for heart failure. We further explored the association of the CS with future cardiovascular hospitalizations. Results: A total of 52 consecutive patients with a confirmed diagnosis of HFpEF were enrolled (mean [SD] age, 57 [15] years; 33 [63%] male). The CS values are significantly higher in the patients with HFpEF (median [interquartile range (IQR)], 1.85 [1.51-2.28]) than in the 2 control cohorts (healthy control participants: median [IQR], -0.03 [-0.48 to 0.41]; control participants with risk factors only: median [IQR], -0.08 [-0.75 to 0.42]; P < .001). For patients with HFpEF, the CS outperforms NT-proBNP when the comparator group was either healthy control participants (CS: area under curve [AUC], 0.98 [95% CI, 0.96-1.00]; NT-proBNP level: AUC, 0.93 [95% CI, 0.88-0.99]; P < .001) or those with risk factors (CS: AUC, 0.98 [95% CI, 0.97-1.00]; NT-proBNP: AUC, 0.93 [95% CI, 0.88-0.99]; P < .001). Kaplan-Meier analysis of 1-year cardiovascular hospitalizations adjusted for age, sex, body mass index, and NT-proBNP levels reveals that patients with HFpEF with CS greater than or equal to 1.80 have a hazard ratio of 3.8 (95% CI, 1.3-11.2; P = .02) for hospitalizations compared with those with scores less than 1.80. Conclusions and Relevance: If further validated, the plasma CS, a marker of transverse tubule dysfunction, may serve as a biomarker of cardiomyocyte remodeling that has the potential to aide in the diagnosis of HFpEF.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/sangue , Insuficiência Cardíaca/diagnóstico , Hospitalização/tendências , Proteínas Nucleares/sangue , Volume Sistólico/fisiologia , Proteínas Supressoras de Tumor/sangue , Biomarcadores/sangue , Feminino , Seguimentos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Prognóstico , Precursores de Proteínas , Índice de Gravidade de Doença , Função Ventricular Esquerda
5.
Respir Med Case Rep ; 20: 10-13, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27872804

RESUMO

Pulmonary veno-occlusive disease (PVOD) is rare condition which can lead to severe pulmonary hypertension, right ventricular dysfunction, and cardiopulmonary failure. The diagnosis of PVOD can be challenging due to its nonspecific symptoms and its similarity to idiopathic pulmonary arterial hypertension and interstitial lung disease in terms of diagnostic findings. This case describes a 57 year old female patient who presented with a 5-month history of progressive dyspnea on exertion and nonproductive cough. Workup at another hospital was nonspecific and the patient underwent surgical lung biopsy due to concern for interstitial lung disease. She subsequently became hemodynamically unstable and was transferred to our hospital where she presented with severe hypoxemia, hypotension, and suprasystemic pulmonary artery pressures. Preliminary lung biopsy results suggested idiopathic pulmonary arterial hypertension and the patient was started on vasodilating agents, including continuous epoprostenol infusion. Pulmonary artery pressures decreased but remained suprasystemic and the patient did not improve. Final review of the biopsy by a specialized laboratory revealed a diagnosis of PVOD after which vasodilating therapy was immediately weaned off. Evaluation for dual heart-lung transplantation was begun. The patient's hospital course was complicated by hypotension requiring vasopressors, worsening right ventricular dysfunction, and acute kidney injury. During the transplantation evaluation, the patient decided that she did not want to undergo continued attempts at stabilization of her progressive multi-organ dysfunction and she was transitioned to comfort care. She expired hours after removing inotropic support.

6.
J Heart Lung Transplant ; 30(11): 1250-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21676629

RESUMO

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) provides hemodynamic support in refractory cardiogenic shock and may be used after heart transplantation for primary graft dysfunction or rejection. We hypothesized that survival after ECMO support is contingent upon patient selection. METHODS: We examined consecutive adult heart transplant recipients at a single center who underwent transplantation between 1997 and 2009 and required ECMO support. Patients were divided by clinical presentation: pre-emptive therapy, escalating inotropic requirements despite support by intra-aortic balloon pump (IABP); and salvage therapy, cardiac arrest undergoing cardiopulmonary resuscitation with chest compressions. RESULTS: Between 1997 and 2009, there were 37 instances of ECMO use in 32 patients: 23 episodes (19 patients) for pre-emptive therapy and 14 episodes (14 patients) for salvage therapy; 1 patient had both pre-emptive and salvage therapy. Patients did not differ in age, gender or ischemic time. ECMO support was for a median 6 days in both groups, and the incidence of serious vascular complications was comparable (35% and 36%). In the pre-emptive therapy group, 15 episodes (79%) were associated with survival to hospital discharge and 5 patients (26%) were alive at 1 year. In the salvage therapy group, 2 episodes (14%) were associated with survival to hospital discharge and 1 patient (7%) was alive at 1 year. CONCLUSIONS: ECMO support is a viable option for adult heart transplant recipients with severe rejection and refractory cardiogenic shock. To maximize the benefit of this aggressive approach in heart transplant recipients requires early intervention, with a heightened awareness of this option to facilitate expedited use.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Transplante de Coração/métodos , Cuidados Intraoperatórios/métodos , Choque Cardiogênico/prevenção & controle , Adulto , California/epidemiologia , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/prevenção & controle , Insuficiência Cardíaca/cirurgia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Choque Cardiogênico/epidemiologia , Taxa de Sobrevida/tendências , Resultado do Tratamento , Adulto Jovem
7.
Liver Transpl ; 17(7): 809-13, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21425429

RESUMO

Percutaneous coronary intervention (PCI) has traditionally not been an option for patients with end-stage liver disease (ESLD) and coronary artery disease (CAD). This retrospective study was designed to demonstrate the feasibility and safety of PCI in liver transplant candidates. Patients with ESLD and hemodynamically significant CAD who were otherwise deemed to be acceptable candidates for liver transplantation underwent PCI. The procedural success rates, mortality and myocardial infarction rates, and bleeding outcomes were examined. Sixteen patients with ESLD underwent PCI: 15 with bare-metal stents (1.3 stents per patient on average) and 1 with balloon angioplasty alone. The median diameter stenosis per lesion was 80%, the median platelet count was 68 × 10(9) /L, the median international normalized ratio was 1.3, and the median Model for End-Stage Liver Disease score was 13. PCI was successful in 94% of the patients. One patient had a suboptimal residual stenosis of 50% after stenting. There were no in-hospital or 30-day deaths or myocardial infarctions, and no patients developed hematomas. One patient required a 1-U platelet transfusion, and another required 1 U of packed red blood cells. All patients remained clinically stable 1 month after PCI. Nine of the 16 patients were listed for liver transplantation, and 3 patients underwent liver transplantation. In conclusion, we have demonstrated the safety and feasibility of PCI in a small cohort of patients with ESLD and hemodynamically significant CAD, the majority of whom had significant thrombocytopenia. Larger studies are required to determine whether PCI is an effective treatment strategy for patients with ESLD and hemodynamically significant CAD who otherwise would not be candidates for liver transplantation.


Assuntos
Angioplastia Coronária com Balão/métodos , Doença Hepática Terminal/terapia , Transplante de Fígado/métodos , Idoso , Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Prognóstico , Stents , Trombocitopenia/sangue , Resultado do Tratamento
8.
Am J Physiol Heart Circ Physiol ; 294(4): H1956-62, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18296564

RESUMO

Prior work in animals and humans suggests that muscle mechanoreceptor control of sympathetic activation [muscle sympathetic nerve activity (MSNA)] during exercise in heart failure (HF) patients is heightened compared with that of healthy humans and that muscle mechanoreceptors are sensitized by metabolic by-products. We sought to determine whether cyclooxygenase products and/or endogenous adenosine, two metabolites of ischemic exercise, sensitize muscle mechanoreceptors during rhythmic handgrip (RHG) exercise in HF patients. Indomethacin, which inhibits the production of prostaglandins, and saline control were infused in 12 HF patients. In a different protocol, aminophylline, which inhibits adenosine receptors, and saline control were infused in 12 different HF patients. MSNA was recorded (microneurography). During exercise following saline, MSNA increased in the first minute of exercise, consistent with baseline heightened mechanoreceptor sensitivity. MSNA continued to increase during 3 min of RHG, indicative that muscle mechanoreceptors are sensitized by ischemia metabolites. Indomethacin, but not aminophylline, markedly attenuated the increase in MSNA during the entire 3 min of low-level rhythmic exercise, consistent with the sensitization of muscle mechanoreceptors by cyclooxygenase products. Interestingly, even the early increase in MSNA was abolished by indomethacin infusion, indicative of the very early generation of cyclooxygenase products after the onset of exercise in HF patients. In conclusion, muscle mechanoreceptors mediate the increase in MSNA during low-level RHG exercise in HF. Cyclooxygenase products, but not endogenous adenosine, play a central role in muscle mechanoreceptor sensitization. Finally, muscle mechanoreceptors in patients with HF have heightened basal sensitivity to mechanical stimuli, which also appears to be mediated by the early generation of cyclooxygenase products, resulting in exaggerated early increases in MSNA.


Assuntos
Insuficiência Cardíaca/metabolismo , Mecanorreceptores/metabolismo , Mecanotransdução Celular , Contração Muscular , Músculo Esquelético/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Reflexo , Sistema Nervoso Simpático/fisiopatologia , Adenosina/metabolismo , Adulto , Aminofilina/administração & dosagem , Pressão Sanguínea , Inibidores de Ciclo-Oxigenase/administração & dosagem , Método Duplo-Cego , Feminino , Força da Mão , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Humanos , Indometacina/administração & dosagem , Infusões Intravenosas , Masculino , Mecanorreceptores/efeitos dos fármacos , Mecanorreceptores/fisiopatologia , Mecanotransdução Celular/efeitos dos fármacos , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/inervação , Nervo Fibular/fisiopatologia , Antagonistas de Receptores Purinérgicos P1 , Receptores Purinérgicos P1/metabolismo , Reflexo/efeitos dos fármacos , Projetos de Pesquisa , Sistema Nervoso Simpático/efeitos dos fármacos , Fatores de Tempo
9.
Am Heart J ; 154(5): 877-83, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17967593

RESUMO

BACKGROUND: The aim of this study was to determine the effects of a home-based exercise program on clinical outcomes. Exercise training improves exercise capacity in patients with heart failure (HF) but the long-term effects on clinical outcomes remain unknown. METHODS: We randomized 173 patients with systolic HF to control (n = 87) or home-based exercise (n = 86). The primary end point was a composite of all-cause hospitalizations, emergency department admissions, urgent transplantation, and death at 12 months. Functional performance (as assessed by cardiopulmonary exercise testing and the 6-minute walk test), quality of life, and psychological states were measured at baseline, 3 months, and 6 months. RESULTS: There was no significant difference between experimental and control groups in the combined clinical end point at 12 months and in functional status, quality of life, or psychological states over 6 months. Patients in the exercise group had a lower incidence of multiple (2 or more) hospitalizations compared with the control group: 12.8% versus 26.6%, respectively (P = .018). CONCLUSIONS: A home-based walking program that incorporated aerobic and resistance exercise did not result in improved clinical outcomes at 1-year follow-up in this cohort of patients with systolic HF. However, the exercise program resulted in reduced rehospitalization rates.


Assuntos
Terapia por Exercício/métodos , Insuficiência Cardíaca/terapia , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/psicologia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Psicológicos , Troca Gasosa Pulmonar/fisiologia , Qualidade de Vida , Resultado do Tratamento
10.
J Heart Lung Transplant ; 24(11): 1736-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16297773

RESUMO

BACKGROUND: Outcomes from this trial's first year data demonstrated significant benefit in heart transplant patients treated with pravastatin in cholesterol levels, survival, rejection with hemodynamic compromise, the development of cardiac allograft vasculopathy, and decreased natural killer cell cytotoxicity. Other heart transplant studies have shown similar benefit. We now report the 10-year follow-up of this study. METHODS: Ninety-seven heart transplant recipients were randomized to pravastatin (n = 47) or no pravastatin (n = 50) within 2 weeks after surgery both in combination with cyclosporine and corticosteroids. Ten-year outcomes include survival, cholesterol levels, and development of cardiac allograft vasculopathy documented by coronary angiography. RESULTS: Forty-two percent of the control patients crossed over to pravastatin treatment during the second year of the study, and 81% of the control patients were eventually placed on statin therapy by the 10-year follow-up. The control group had subsequent low and comparable cholesterol levels in Years 2 to 10 of the study compared with the patients originally randomized to pravastatin. Intent-to-treat analysis demonstrated that the pravastatin group compared with control had increased 10-year survival (68% vs 48%, p = 0.026). The 10-year freedom from angiographic cardiac allograft vasculopathy and/or death in the pravastatin group was significantly greater compared with the control group (43% vs 20%, p = 0.009). CONCLUSION: The 10-year follow-up of this study suggests that the use of pravastatin in heart transplant patients maintains survival benefit and appears to reduce the development of cardiac allograft vasculopathy.


Assuntos
Doença das Coronárias/prevenção & controle , Transplante de Coração , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pravastatina/uso terapêutico , Adulto , Angiografia Coronária , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Coração/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento , Ultrassonografia de Intervenção
11.
Am J Physiol Heart Circ Physiol ; 287(5): H1937-43, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15475527

RESUMO

Prior work in animals suggests that muscle mechanoreceptor control of sympathetic activation (MSNA) during exercise in heart failure (HF) is heightened and that muscle mechanoreceptors are sensitized by metabolic by-products. We sought to determine whether 1) muscle mechanoreceptor control of MSNA is enhanced in HF patients and 2) lactic acid sensitizes muscle mechanoreceptors during rhythmic handgrip (RHG) exercise in healthy humans and patients with HF. Dichloroacetate (DCA), which reduces the production of lactic acid, or saline control was infused in 12 patients with HF and 13 controls during RHG. MSNA was recorded (microneurography). After saline was administered and during exercise thereafter, MSNA increased earlier in HF compared with controls, consistent with baseline-heightened mechanoreceptor sensitivity. In both HF and controls, MSNA increased during the 3-min exercise protocol, consistent with further sensitization of muscle mechanoreceptors by metabolic by-product(s). During posthandgrip circulatory arrest, MSNA returned rapidly to baseline levels, excluding the muscle metaboreceptors as mediators of the sympathetic excitation during RHG. To isolate muscle mechanoreceptors from central command, we utilized passive exercise in 8 HF and 11 controls, and MSNA was recorded. MSNA increased significantly during passive exercise in HF but not in controls. In conclusion, muscle mechanoreceptors mediate the increase in MSNA during low-level RHG exercise in healthy humans, and this muscle mechanoreceptor control is augmented further in HF. Neither lactate generation nor the fall in pH during RHG plays a central role in muscle mechanoreceptor sensitization. Finally, muscle mechanoreceptors in patients with HF have heightened basal sensitivity to mechanical stimuli resulting in exaggerated early increases in MSNA.


Assuntos
Baixo Débito Cardíaco/fisiopatologia , Exercício Físico , Ácido Láctico/metabolismo , Mecanorreceptores/fisiopatologia , Músculo Esquelético/inervação , Sistema Nervoso Simpático/fisiopatologia , Braço , Constrição , Ácido Dicloroacético/farmacologia , Método Duplo-Cego , Feminino , Força da Mão , Humanos , Ácido Láctico/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Músculo Esquelético/irrigação sanguínea , Periodicidade
12.
AACN Clin Issues ; 14(4): 477-87, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14595207

RESUMO

Sleep disturbances have a major impact on physical functioning, emotional well-being, and quality of life, but are not well described in patients with heart failure (HF). Eighty-four HF patients completed a sleep survey and provided demographic and clinical data. Seventy percent of the patients were male with a mean age of 54 years and a mean left ventricular ejection fraction of 22%. Forty-seven patients (56%) reported trouble sleeping and one-third used sleeping medication. The most frequently reported problems were inability to sleep flat (51%), restless sleep (44%), trouble falling asleep (40%), and awakening early (39%). Using logistic regression, physiological variables were tested as predictors of sleep disturbance. Severity of HF, age, gender, etiology, obesity, smoking, and use of beta-blockers were not predictors of sleep disturbance. HF patients experience significant sleep disturbances, which are not predicted by severity of symptoms or clinical status. Problems with sleep are an important component of a clinical assessment in this vulnerable population.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Transtornos do Sono-Vigília/fisiopatologia , Baixo Débito Cardíaco/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários
13.
Am J Transplant ; 2(6): 539-45, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12118898

RESUMO

Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection.


Assuntos
Transplante de Coração/mortalidade , Avaliação de Resultados em Cuidados de Saúde , Adolescente , Adulto , Idoso , Feminino , Transplante de Coração/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Doadores de Tecidos , Resultado do Tratamento
14.
J Card Fail ; 8(6): 399-406, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12528093

RESUMO

BACKGROUND: In heart failure (HF) patients, muscle sympathetic nerve activity is increased, and HF patients with the greatest sympathetic activation have the poorest prognosis. In animals, acupuncture is sympathoinhibitory, and the most profound sympathoinhibition occurs in animals with the highest resting sympathetic nerve activity. The purpose of this study was to test the hypothesis that acupuncture is sympathoinhibitory in humans with HF. METHODS AND RESULTS: Fifteen advanced HF patients underwent acute mental stress testing before and during (1) "real" acupuncture (n = 10), (2) non-acupoint acupuncture (n = 10), and (3) no-needle acupuncture control (n = 10). Muscle sympathetic nerve activity (MSNA) was recorded using peroneal microneurography. Resting MSNA was not different before and after acupuncture (52 +/- 22 versus 50 +/- 21 bursts/min, P = NS). During mental stress, SNA increased significantly. This increase was eliminated following real acupuncture (mean delta MSNA pre-acupuncture versus post-acupuncture: 149 +/- 171 versus -169 +/- 130, P =.03), but not after non-acupoint or no-needle acupuncture controls. The changes in blood pressure and heart rate during mental stress were not attenuated by real or control acupuncture. CONCLUSION: Acute acupuncture attenuates sympathoexcitation during mental stress in advanced HF patients.


Assuntos
Terapia por Acupuntura , Insuficiência Cardíaca/terapia , Estresse Psicológico/terapia , Adulto , Vias Autônomas/fisiologia , Pressão Sanguínea/fisiologia , Eletrocardiografia , Frequência Cardíaca/fisiologia , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Sistema Nervoso Simpático/fisiologia , Resultado do Tratamento
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