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1.
Catheter Cardiovasc Interv ; 91(5): 894-896, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28944588

RESUMO

Mechanical cardiovascular support devices are now widely used both in the setting of cardiogenic shock as well as during high risk cardiac catheterization procedures. We report a case of a young female patient who presented with presumed myocarditis and rapidly deteriorating decompensated heart failure requiring the implantation of an Impella Circulatory Support System. Upon transfer to our facility it was discovered that during transport, the Impella device had migrated through the left ventricle. She was emergently taken to the operating room where the Impella was surgically removed and biventricular support devices were placed. The patient eventually expired after weeks of treatment in the intensive care unit. We believe this is the first recorded case of an Impella device perforating the left ventricle. Particularly in cases of newly discovered pericardial effusion, change in waveform on the Impella controller placement signal or rapid decompensation, physicians should consider this rare but potentially catastrophic complication associated with mechanical left ventricular support devices.


Assuntos
Traumatismos Cardíacos/etiologia , Ventrículos do Coração/lesões , Coração Auxiliar , Implantação de Prótese/efeitos adversos , Implantação de Prótese/instrumentação , Choque Cardiogênico/terapia , Função Ventricular Esquerda , Adulto , Evolução Fatal , Feminino , Traumatismos Cardíacos/diagnóstico , Traumatismos Cardíacos/fisiopatologia , Traumatismos Cardíacos/terapia , Ventrículos do Coração/fisiopatologia , Humanos , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/etiologia , Choque Cardiogênico/fisiopatologia
3.
Clin Transplant ; 29(9): 829-34, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26171948

RESUMO

BACKGROUND: The elevated baseline heart rate (HR) of a heart transplant recipient has previously been considered inconsequential. However, we hypothesized that a resting HR above 100 beats per minute (bpm) may be associated with morbidity and mortality. METHODS: The U.T.A.H. Cardiac Transplant Program studied patients who received a heart transplant between 2000 and 2011. Outpatient HR values for each patient were averaged during the first year post-transplant. The study cohort was divided into two groups: the tachycardic (TC) (HR > 100 bpm) and the non-TC group (HR ≤ 100 bpm) in which mortality, incidence of rejection, and cardiac allograft vasculopathy were compared. RESULTS: Three hundred and ten patients were included as follows: 73 in the TC and 237 in the non-TC group. The TC group had a higher risk of a 10-yr all-cause mortality (p = 0.004) and cardiovascular mortality (p = 0.044). After adjustment for donor and recipient characteristics in multivariable logistic regression analysis, the hazard ratio was 3.9, (p = 0.03, CI: 1.2-13.2) and 2.6 (p = 0.02, CI: 1.2-5.5) for cardiovascular mortality and all-cause mortality, respectively. CONCLUSION: Heart transplant recipients with elevated resting HR appear to have higher mortality than those with lower resting HR. Whether pharmacologically lowering the HR would result in better outcomes warrants further investigation.


Assuntos
Transplante de Coração , Complicações Pós-Operatórias , Taquicardia/etiologia , Adulto , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Feminino , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/mortalidade , Transplante de Coração/mortalidade , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Taquicardia/diagnóstico , Taquicardia/mortalidade
4.
Circulation ; 127(4): 452-62, 2013 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23271796

RESUMO

BACKGROUND: Survival of patients on left ventricular assist devices (LVADs) has improved. We examined the differences in risk of adverse outcomes between LVAD-supported and medically managed candidates on the heart transplant waiting list. METHODS AND RESULTS: We analyzed mortality and morbidity in 33,073 heart transplant candidates registered on the United Network for Organ Sharing (UNOS) waiting list between 1999 and 2011. Five groups were selected: patients without LVADs in urgency status 1A, 1B, and 2; patients with pulsatile-flow LVADs; and patients with continuous-flow LVADs. Outcomes in patients requiring biventricular assist devices, total artificial heart, and temporary VADs were also analyzed. Two eras were defined on the basis of the approval date of the first continuous-flow LVAD for bridge to transplantation in the United States (2008). Mortality was lower in the current compared with the first era (2.1%/mo versus 2.9%/mo; P<0.0001). In the first era, mortality of pulsatile-flow LVAD patients was higher than in status 2 (hazard ratio [HR], 2.15; P<0.0001) and similar to that in status 1B patients (HR, 1.04; P=0.61). In the current era, patients with continuous-flow LVADs had mortality similar to that of status 2 (HR, 0.80; P=0.12) and lower mortality compared with status 1A and 1B patients (HR, 0.24 and 0.47; P<0.0001 for both comparisons). However, status upgrade for LVAD-related complications occurred frequently (28%) and increased the mortality risk (HR, 1.75; P=0.001). Mortality was highest in patients with biventricular assist devices (HR, 5.00; P<0.0001) and temporary VADs (HR, 7.72; P<0.0001). CONCLUSIONS: Mortality and morbidity on the heart transplant waiting list have decreased. Candidates supported with contemporary continuous-flow LVADs have favorable waiting list outcomes; however, they worsen significantly once a serious LVAD-related complication occurs. Transplant candidates requiring temporary and biventricular support have the highest risk of adverse outcomes. These results may help to guide optimal allocation of donor hearts.


Assuntos
Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/cirurgia , Transplante de Coração/mortalidade , Coração Auxiliar/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Modelos de Riscos Proporcionais , Sistema de Registros/estatística & dados numéricos , Fatores de Risco , Estados Unidos/epidemiologia , Listas de Espera/mortalidade
5.
Cardiology ; 122(2): 104-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22759389

RESUMO

ß-Adrenergic receptors (ß-AR) are central to the overall regulation of cardiac function. From the first proposed receptor/transmitter concept to the latest clinical ß-blocker trials ß-AR have been shown to play an important role in cardiac disease and heart failure in particular. This study provides a historical perspective, reviews the latest discoveries and beliefs, and discusses the current clinical practices of ß-AR and their modulation with their associated guanine-nucleotide regulatory protein/adenylylcyclasesignal transduction pathways.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Receptores Adrenérgicos beta/fisiologia , Antagonistas Adrenérgicos beta/uso terapêutico , Proteínas de Ligação ao GTP/fisiologia , Insuficiência Cardíaca/etiologia , História do Século XX , Humanos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos beta/classificação , Receptores Adrenérgicos beta/história , Transdução de Sinais/fisiologia
6.
Circ Heart Fail ; 15(6): e008706, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35658464

RESUMO

BACKGROUND: Our current understanding of right heart failure (RHF) post-left ventricular assist device (LVAD) is lacking. Recently, a new Interagency Registry for Mechanically Assisted Circulatory Support definition of RHF was introduced. Based on this definition, we investigated natural history, risk factors, and outcomes of post-LVAD RHF. METHODS: Patients implanted with continuous flow LVAD between June 2, 2014, and June 30, 2016 and registered in the Interagency Registry for Mechanically Assisted Circulatory Support/Society of Thoracic Surgeons Database were included. RHF incidence and predictors, and survival after RHF were assessed. The manifestations of RHF which were separately analyzed were elevated central venous pressure, peripheral edema, ascites, and use of inotropes. RESULTS: Among 5537 LVAD recipients (mean 57±13 years, 49% destination therapy, support 18.9 months) prevalence of 1-month RHF was 24%. Of these, RHF persisted at 12 months in 5.3%. In contrast, de novo RHF, first identified at 3 months, occurred in 5.1% and persisted at 12 months in 17% of these, and at 6 months occurred in 4.8% and persisted at 12 months in 25%. Higher preimplant blood urea nitrogen (ORs,1.03-1.09 per 5 mg/dL increase; P<0.0001), previous tricuspid valve repair/replacement (ORs, 2.01-10.09; P<0.001), severely depressed right ventricular systolic function (ORs,1.17-2.20; P=0.004); and centrifugal versus axial LVAD (ORs,1.15-1.78; P=0.001) represented risk factors for RHC incidence at 3 months. Patients with persistent RHF at 3 months had the lowest 2-year survival (57%) while patients with de novo RHF or RHF which resolved by 3 months had more favorable survival outcomes (75% and 78% at 2 years, respectively; P<0.001). CONCLUSIONS: RHF at 1 or 3 months post-LVAD was a common and frequently transient condition, which, if resolved, was associated with relatively favorable prognosis. Conversely, de novo, late RHF post-LVAD (>6 months) was more frequently a persistent disorder and associated with increased mortality. The 1-, 3-, and 6-month time points may be used for RHF assessment and risk stratification in LVAD recipients.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Ventrículos do Coração/diagnóstico por imagem , Coração Auxiliar/efeitos adversos , Humanos , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
7.
JAMA Cardiol ; 6(8): 957-962, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33950162

RESUMO

Importance: Heart failure with recovered ejection fraction (HFrecEF) is a recently recognized phenotype of patients with a history of reduced left ventricular ejection fraction (LVEF) that has subsequently normalized. It is unknown whether such LVEF improvement is associated with improvements in health status. Objective: To examine changes in health-related quality of life in patients with heart failure with reduced ejection fraction (HFrEF) whose LVEF normalized, compared with those whose LVEF remains reduced and those with HF with preserved EF (HFpEF). Design, Setting, and Participants: This prospective cohort study was conducted at a tertiary care hospital from November 2016 to December 2018. Consecutive patients seen in a heart failure clinic who completed patient-reported outcome assessments were included. Clinical data were abstracted from the electronic health record. Data analysis was completed from February to December 2020. Main Outcomes and Measures: Changes in Kansas City Cardiomyopathy Questionnaire overall summary score, Visual Analog Scale score, and Patient-Reported Outcomes Measurement Information System domain scores on physical function, fatigue, depression, and satisfaction with social roles over 1-year follow-up. Results: The study group included 319 patients (mean [SD] age, 60.4 [15.5] years; 120 women [37.6%]). At baseline, 212 patients (66.5%) had HFrEF and 107 (33.5%) had HFpEF. At a median follow-up of 366 (interquartile range, 310-421) days, LVEF had increased to 50% or more in 35 patients with HFrEF (16.5%). Recovery of systolic function was associated with heart failure-associated quality-of-life improvement, such that for each 10% increase in LVEF, the Kansas City Cardiomyopathy Questionnaire score improved by an mean (SD) of 4.8 (1.6) points (P = .003). Recovery of LVEF was also associated with improvement of physical function, satisfaction with social roles, and a reduction in fatigue. Conclusions and Relevance: Among patients with HFrEF in this study, normalization of left ventricular systolic function was associated with a significant improvement in health-related quality of life.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Qualidade de Vida , Recuperação de Função Fisiológica/fisiologia , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos
8.
Am J Physiol Heart Circ Physiol ; 299(5): H1653-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20833963

RESUMO

To better characterize the contribution of both central and peripheral mechanisms to passive limb movement-induced hyperemia, we studied nine recent (<2 yr) heart transplant (HTx) recipients (56 ± 4 yr) and nine healthy controls (58 ± 5 yr). Measurements of heart rate (HR), stroke volume (SV), cardiac output (CO), and femoral artery blood flow were recorded during passive knee extension. Peripheral vascular function was assessed using brachial artery flow-mediated dilation (FMD). During passive limb movement, the HTx recipients lacked an HR response (0 ± 0 beats/min, Δ0%) but displayed a significant increase in CO (0.4 ± 0.1 l/min, Δ5%) although attenuated compared with controls (1.0 ± 0.2 l/min, Δ18%). Therefore, the rise in CO in the HTx recipients was solely dependent on increased SV (5 ± 1 ml, Δ5%) in contrast with the controls who displayed significant increases in both HR (6 ± 2 beats/min, Δ11%) and SV (5 ± 2 ml, Δ7%). The transient increase in femoral blood volume entering the leg during the first 40 s of passive movement was attenuated in the HTx recipients (24 ± 8 ml) compared with controls (93 ± 7 ml), whereas peripheral vascular function (FMD) appeared similar between HTx recipients (8 ± 2%) and controls (6 ± 1%). These data reveal that the absence of an HR increase in HTx recipients significantly impacts the peripheral vascular response to passive movement in this population and supports the concept that an increase in CO is a major contributor to exercise-induced hyperemia.


Assuntos
Exercício Físico/fisiologia , Artéria Femoral/fisiologia , Frequência Cardíaca/fisiologia , Transplante de Coração/fisiologia , Hiperemia/fisiopatologia , Perna (Membro)/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Volume Sanguíneo/fisiologia , Monóxido de Carbono/metabolismo , Débito Cardíaco/fisiologia , Estudos de Casos e Controles , Feminino , Hemodinâmica/fisiologia , Humanos , Perna (Membro)/fisiologia , Masculino , Pessoa de Meia-Idade , Volume Sistólico/fisiologia
9.
JACC Heart Fail ; 8(4): 302-312, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32241537

RESUMO

OBJECTIVES: The aim of this study was to evaluate the impact of a shared-care model on outcomes in patients with left ventricular assist devices (LVADs) living in remote locations. BACKGROUND: Health care delivery through shared-care models has been shown to improve outcomes in patients with chronic diseases. However, the impact of shared-care models on outcomes in patients with LVAD is unknown. METHODS: LVAD recipients in the authors' program (2007 to 2018) were classified based on the levels of care provided and training and resources used: level 1, was defined as outpatient primary care without LVAD-specific care; level 2 was level 1 services and outpatient LVAD-specific care; level 3 was level 2 services and inpatient LVAD-specific care and implantation center (IC). The Kaplan-Meier method was used to compare rates of survival, bleeding, pump thrombosis, infection, neurologic events, and readmissions among levels of care. RESULTS: A total of 336 patients were included, with 255 patients (75.9%) cared for in shared-care facilities. Median follow-up was 810 (interquartile range: 321 to 1,096) days. In comparison to patients cared for by IC, patients at levels 2 and 3 shared-care centers had similar rates of death, bleeding, neurologic events, pump thromboses, and infections. However, the rates of death, pump thromboses, and infections were higher for level 1 patients than in IC patients. CONCLUSIONS: Shared health care is an effective strategy to deliver care to patients with LVAD living in remote locations. However, patients in shared-care facilities unable to provide LVAD-specific care are at higher risk of unfavorable outcomes. Availability of LVAD-specific care should be strongly considered during patient selection and every effort made to ensure LVAD-specific training and resources are available at shared-care facilities.


Assuntos
Atenção à Saúde/métodos , Insuficiência Cardíaca/terapia , Ventrículos do Coração/fisiopatologia , Coração Auxiliar , Qualidade de Vida , Função Ventricular Esquerda/fisiologia , Idoso , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
10.
JACC Basic Transl Sci ; 5(9): 871-883, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32838074

RESUMO

Using serial analysis of myocardial gene expression employing endomyocardial biopsy starting material in a dilated cardiomyopathy cohort, we show that mRNA expression of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) cardiac myocyte receptor ACE2 is up-regulated with remodeling and with reverse remodeling down-regulates into the normal range. The proteases responsible for virus-cell membrane fusion were expressed but not regulated with remodeling. In addition, a new candidate for SARS-CoV-2 cell binding and entry was identified, the integrin encoded by ITGA5. Up-regulation in ACE2 in remodeled left ventricles may explain worse outcomes in patients with coronavirus disease 2019 who have underlying myocardial disorders, and counteracting ACE2 up-regulation is a possible therapeutic approach to minimizing cardiac damage.

11.
J Pharm Technol ; 25(2): 71-78, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19675680

RESUMO

BACKGROUND: Abnormal glucose metabolism and insulin resistance have been associated with heart failure incidence, severity, and mortality. Metabolic parameters such as hepatic glucose production may be altered by beta-adrenoceptor antagonists in patients with heart failure. OBJECTIVE: This study evaluated the effects of metoprolol or carvedilol up-titration on fasting glucose, insulin resistance and beta(2)-mediated glucose production in patients with chronic heart failure. METHODS: This was a prospective, randomized, active comparator study in 15 patients with AHA/ACC Stage C systolic dysfunction HF stable on medical therapy. Participants were randomized to metoprolol 25mg daily or carvedilol 3.125mg twice daily. Metoprolol was titrated to a target of 200mg daily, and carvedilol was titrated to 25mg twice daily over 8weeks. Insulin resistance as assessed by the homeostatic model, and terbutaline-induced glucose production (AUC(0-180)), were assessed at baseline and at 4 subsequent beta-blocker titration visits over 8 weeks. RESULTS: In all 15 patients, terbutaline-induced glucose AUC(0-180) decreased (p=0.0006) as beta-blocker doses increased. A significant reduction in glucose AUC(0-180) compared to baseline was only noted in patients taking metoprolol at 100mg daily (-2424.6 [95% CI -372.6 to -4478.4] mg/dL*min) and 200mg daily (-2437.2 [95% CI -15.1 to -4604.4] mg/dL*min), and not observed in those taking carvedilol. After beta-blocker titration, fasting glucose concentrations for the metoprolol and carvedilol groups were 86.9 (95% CI 89.8-101.6) mg/dL and 95.7 (95% CI 89.8-101.6) mg/dL, respectively (p=0.0273), adjusted for baseline values. There was no significant difference between metoprolol and carvedilol on insulin resistance. CONCLUSION: Increasing doses of beta-blockers are associated with decreased in beta2-mediated glucose production in heart failure. Metoprolol, but not carvedilol, decreases hepatic glucose production at commonly used heart failure doses.

13.
PLoS One ; 14(8): e0221519, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31469842

RESUMO

OBJECTIVES: To investigate the biologic relevance of cross-platform concordant changes in gene expression in intact human failing/hypertrophied ventricular myocardium undergoing reverse remodeling. BACKGROUND: Information is lacking on genes and networks involved in remodeled human LVs, and in the associated investigative best practices. METHODS: We measured mRNA expression in ventricular septal endomyocardial biopsies from 47 idiopathic dilated cardiomyopathy patients, at baseline and after 3-12 months of ß-blocker treatment to effect left ventricular (LV) reverse remodeling as measured by ejection fraction (LVEF). Cross-platform gene expression change concordance was investigated in reverse remodeling Responders (R) and Nonresponders (NR) using 3 platforms (RT-qPCR, microarray, and RNA-Seq) and two cohorts (All 47 subjects (A-S) and a 12 patient "Super-Responder" (S-R) subset of A-S). RESULTS: For 50 prespecified candidate genes, in A-S mRNA expression 2 platform concordance (CcpT), but not single platform change, was directly related to reverse remodeling, indicating CcpT has biologic significance. Candidate genes yielded a CcpT (PCR/microarray) of 62% for Responder vs. Nonresponder (R/NR) change from baseline analysis in A-S, and ranged from 38% to 100% in S-R for PCR/microarray/RNA-Seq 2 platform comparisons. Global gene CcpT measured by microarray/RNA-Seq was less than for candidate genes, in S-R R/NR 17.5% vs. 38% (P = 0.036). For S-R global gene expression changes, both cross-cohort concordance (CccT) and CcpT yielded markedly greater values for an R/NR vs. an R-only analysis (by 22 fold for CccT and 7 fold for CcpT). Pathway analysis of concordant global changes for R/NR in S-R revealed signals for downregulation of multiple phosphoinositide canonical pathways, plus expected evidence of a ß1-adrenergic receptor gene network including enhanced Ca2+ signaling. CONCLUSIONS: Two-platform concordant change in candidate gene expression is associated with LV biologic effects, and global expression concordant changes are best identified in an R/NR design that can yield novel information.

14.
J Heart Lung Transplant ; 38(8): 858-869, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072751

RESUMO

BACKGROUND: The new heart allocation system in the United States prioritizes patients supported by temporary mechanical circulatory support (TMCS) devices over those with uncomplicated durable continuous-flow left ventricular assist devices (CF-LVADs), which may increase the number of patients bridged to transplant with TMCS. Limited data are available in guiding post-transplant outcomes with various TMCS devices. We sought to describe post-transplant outcome and identify clinical variables associated with post-transplant outcome in patients bridged to transplant with TMCS. METHODS: Using data from the International Society for Heart and Lung Transplantation Thoracic Transplant Registry, we included subjects who underwent transplantation between 2005 and 2016 with known use of mechanical circulatory support. Pre-transplant recipient, donor, and transplant-specific variables were abstracted. The primary outcome was patient survival at 1-year post-transplant. Outcomes of patients bridged to transplant with TMCS were compared with those of patients bridged with CF-LVADs. Cox regression analyses were performed to identify clinical variables associated with the outcomes. RESULTS: There were 6,528 patients bridged to transplant with the following types of mechanical circulatory support: durable CF-LVADs (n = 6,206), extracorporeal membrane oxygenation (ECMO, n = 134), percutaneous temporary CF-LVADs (n = 75), surgically implanted temporary CF-LVADs (n = 38) or surgically implanted temporary BiVAD (n = 75). Bridging with ECMO (hazard ratio 3.79, 95% confidence interval [CI] 2.69-5.34, p < 0.001) or percutaneous temporary CF-LVADs (hazard ratio 1.83, 95% CI 1.09-3.08, p = 0.02) was independently associated with higher risk of mortality. Additional risk factors included older donor age, female/male donor-recipient match, older recipient age, higher recipient body mass index, higher recipient creatinine, and prolonged ischemic time. CONCLUSIONS: This analysis of a large international cohort of patients bridged to transplant with mechanical circulatory support identified ECMO and percutaneous temporary CF-LVADs as predictors of mortality after transplant, along with additional donor and recipient clinical characteristics. These findings may provide guidance to clinicians in decisions on mechanical circulatory support device selection, transplant eligibility, and timing of transplant.


Assuntos
Oxigenação por Membrana Extracorpórea , Transplante de Coração , Coração Auxiliar , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
15.
Am Heart J ; 156(2): 315-21, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18657662

RESUMO

INTRODUCTION: Alpha(1)-adrenergic receptor (alpha(1)-AR) stimulation produces smooth muscle contraction, vasoconstriction, and myocyte hypertrophy, suggesting a potential therapeutic role for alpha(1)-AR antagonists to reduce cardiac workload and myocardial hypertrophy. Preliminary reports suggest that vascular alpha(1)-ARs are desensitized in heart failure (HF) in a manner similar to myocardial beta(1)-ARs. We examined alpha(1)-AR signal transduction by repeat phenylephrine (PE) infusions in patients with HF receiving chronic carvedilol therapy. METHODS: Twelve subjects with HF not currently receiving beta-blockers were up-titrated to maximum tolerable doses of carvedilol. Subjects underwent alpha(1)-AR stimulation testing at study baseline, 2 weeks after each dose titration, and 6 months after maintenance of maximum carvedilol dose. Phenylephrine infusions began at 0.5 microg kg(-1) min(-1), with dose titrations every 10 minutes, to a maximum of 5 microg kg(-1) min(-1). Phenylephrine dose response was evaluated by the PE rate required to elicit a 20 mm Hg increase in systolic blood pressure (BP), designated PS(20). RESULTS: All doses of carvedilol significantly reduced preinfusion measures of heart rate, systolic BP, diastolic BP, and mean arterial pressure. However, carvedilol also produced a paradoxical trend toward PS(20) reduction (indicating increased PE response) that reached significance at the completion of carvedilol dose titration (PS(20) ratio vs baseline = 0.78; P < .001). All effects were maintained over a 6-month treatment period with no evidence of tolerance. CONCLUSIONS: Increasing BP response to PE infusion suggests improvement in vascular alpha(1)-AR signal transduction with chronic carvedilol therapy. This effect is evident despite no detectable tolerance to preinfusion BP reductions. The varying affinities of alpha(1)-AR subtypes for carvedilol and PE may have contributed to this finding.


Assuntos
Antagonistas Adrenérgicos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Carbazóis/farmacologia , Insuficiência Cardíaca/fisiopatologia , Propanolaminas/farmacologia , Receptores Adrenérgicos alfa 1/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Antagonistas Adrenérgicos/uso terapêutico , Agonistas alfa-Adrenérgicos/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carbazóis/uso terapêutico , Carvedilol , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fenilefrina/farmacologia , Propanolaminas/uso terapêutico , Estudos Prospectivos , Receptores Adrenérgicos alfa 1/metabolismo , Sístole , Disfunção Ventricular/tratamento farmacológico
16.
Circ Heart Fail ; 11(11): e005267, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30571195

RESUMO

BACKGROUND: Gastrointestinal bleeding (GIB) is a leading cause of morbidity during continuous-flow left ventricular assist device (CF-LVAD) support. GIB risk assessment could have important implications for candidate selection, informed consent, and postimplant therapeutic strategies. The aim of the study is to derive and validate a predictive model of GIB in CF-LVAD patients. METHODS AND RESULTS: CF-LVAD recipients at the Utah Transplantation Affiliated Hospitals program between 2004 and 2017 were included. GIB associated with a decrease in hemoglobin ≥2 g/dL was the primary end point. A weighted score comprising preimplant variables independently associated with GIB was derived and internally validated. A total of 351 patients (median age, 59 years; 82% male) were included. After a median of 196 days, GIB occurred in 120 (34%) patients. Independent predictors of GIB included age >54 years, history of previous bleeding, coronary artery disease, chronic kidney disease, severe right ventricular dysfunction, mean pulmonary artery pressure <18 mm Hg, and fasting glucose >107 mg/dL. A weighted score termed Utah bleeding risk score, effectively stratified patients based on their probability of GIB: low (0-1 points) 4.8%, intermediate (2-4) 39.8%, and high risk (5-9) 83.8%. Discrimination was good in the development sample (c-index: 0.83) and after internal bootstrap validation (c-index: 0.74). CONCLUSIONS: The novel Utah bleeding risk score is a simple tool that can provide personalized GIB risk estimates in CF-LVAD patients. This scoring system may assist clinicians and investigators in designing tailored risk-based strategies aimed at reducing the burden posed by GIB in the individual CF-LVAD patient and healthcare systems.


Assuntos
Hemorragia Gastrointestinal/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Coração Auxiliar , Disfunção Ventricular Direita/fisiopatologia , Idoso , Anticoagulantes/uso terapêutico , Feminino , Transplante de Coração/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco
17.
Circ Heart Fail ; 11(8): e004759, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30354559

RESUMO

BACKGROUND: Cardiac allograft vasculopathy (CAV) remains an important source of mortality after heart transplant. The aim of our study was to identify structural and microvasculature changes in severe CAV. METHODS AND RESULTS: The study group included heart transplant recipients with severe CAV who underwent retransplantation (severe CAV, n=20). Control groups included time from transplant matched cardiac transplant recipients without CAV (transplant control, n=20), severe ischemic cardiomyopathy patients requiring left ventricular assist device implantation (ischemic control, n=18), and normal hearts donated for research (donor control, n=10). We collected baseline demographic information, echocardiography data, and performed histopathologic examination of myocardial microvasculature. Echocardiographic features of severe CAV included lack of eccentric remodeling and presence of significant diastolic dysfunction. In contrast, diastolic function was preserved in transplant control subjects. Histopathologic examination showed increased interstitial fibrosis among severe CAV, transplant controls, and ischemic control patients. Compared with transplant controls, severe CAV subjects had reduced capillary density and increased capillary wall thickness ( P<0.05). CONCLUSIONS: Our results suggest that the marked diastolic dysfunction and resultant symptoms in patients with severe CAV may be secondary to the loss of microvasculature and remodeling of remaining microvessels rather than a consequence of interstitial fibrosis. The clinical significance and potential therapeutic implications of these unique microvasculature characteristics warrant further investigation.


Assuntos
Capilares/patologia , Doença da Artéria Coronariana/etiologia , Transplante de Coração/efeitos adversos , Remodelação Vascular , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda , Aloenxertos , Biópsia , Capilares/fisiopatologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Circulação Coronária , Diástole , Ecocardiografia Doppler de Pulso , Humanos , Microcirculação , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia
18.
N Engl J Med ; 346(18): 1357-65, 2002 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-11986409

RESUMO

BACKGROUND: Beta-blocker therapy may improve cardiac function in patients with idiopathic dilated cardiomyopathy. We tested the hypothesis that beta-blocker therapy produces favorable functional effects in dilated cardiomyopathy by altering the expression of myocardial genes that regulate contractility and pathologic hypertrophy. METHODS: We randomly assigned 53 patients with idiopathic dilated cardiomyopathy to treatment with a beta-adrenergic-receptor blocking agent (metoprolol or carvedilol) or placebo. The amount of messenger RNA (mRNA) for contractility-regulating genes (those encoding beta1- and beta2-adrenergic receptors, calcium ATPase in the sarcoplasmic reticulum, and alpha- and beta-myosin heavy-chain isoforms) and of genes associated with pathologic hypertrophy (beta-myosin heavy chain and atrial natriuretic peptide) was measured with a quantitative reverse-transcription polymerase chain reaction in total RNA extracted from biopsy specimens of the right ventricular septal endomyocardium. Myocardial levels of beta-adrenergic receptors were also measured. Measurements were conducted at base line and after six months of treatment, and changes in gene expression were compared with changes in the left ventricular ejection fraction as measured by radionuclide ventriculography. RESULTS: Twenty-six of 32 beta-blocker-treated patients (those with complete mRNA measurements) had an improvement in left ventricular ejection fraction of at least 5 ejection-fraction (EF) units (mean [+/-SE] increase, 18.8+/-1.8). As compared with the six beta-blocker-treated patients who did not have a response (mean change, a decrease of 2.5+/-1.8 EF units), those who did have a response had an increase in sarcoplasmic-reticulum calcium ATPase mRNA and alpha-myosin heavy chain mRNA and a decrease in beta-myosin heavy chain mRNA. The change in sarcoplasmic-reticulum calcium ATPase was not present in the patients in the placebo group who had a spontaneous response. There were no differences between those who had a response and those who did not in terms of the change in mRNA or protein expression of beta-adrenergic receptors. CONCLUSIONS: In idiopathic dilated cardiomyopathy, functional improvement related to treatment with beta-blockers is associated with changes in myocardial gene expression.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Cardiomiopatia Dilatada/tratamento farmacológico , Expressão Gênica/efeitos dos fármacos , Miocárdio/metabolismo , Receptores Adrenérgicos beta/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Idoso , ATPases Transportadoras de Cálcio/efeitos dos fármacos , ATPases Transportadoras de Cálcio/genética , ATPases Transportadoras de Cálcio/metabolismo , Carbazóis/farmacologia , Carbazóis/uso terapêutico , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/fisiopatologia , Carvedilol , Feminino , Hemodinâmica , Humanos , Masculino , Metoprolol/farmacologia , Metoprolol/uso terapêutico , Pessoa de Meia-Idade , Cadeias Pesadas de Miosina/efeitos dos fármacos , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Propanolaminas/farmacologia , Propanolaminas/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Adrenérgicos beta/genética , Volume Sistólico/efeitos dos fármacos , Miosinas Ventriculares/efeitos dos fármacos , Miosinas Ventriculares/genética , Miosinas Ventriculares/metabolismo
19.
Am Heart J ; 153(6): 1029-36, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17540206

RESUMO

BACKGROUND: Community patients with heart failure (HF) are older, less often treated by HF specialists, and have more comorbidity than those in randomized clinical trials. These differences might affect beta-blocker prescribing in HF. METHODS: To explore patterns of beta-blocker prescribing for HF in the community and their association with outcomes, we determined carvedilol doses at end titration in 4113 patients from a community-based beta-blocker HF registry according to physician and patient characteristics, HF severity, and rates of hospitalization and death. RESULTS: Female sex, age > or = 65 years, and left ventricular ejection fraction > or = 35% were associated with lower beta-blocker doses. Average daily dose of beta-blocker was lower with worse baseline New York Heart Association class. More patients of cardiologists achieved carvedilol doses > or = 25 mg twice daily, whereas in those of noncardiologists lower doses were more common. Relative risk of HF hospitalizations or all-cause death was significantly lower with higher doses of beta-blocker. CONCLUSIONS: Beta-blocker dosing in community HF appears lower than in randomized clinical trials, especially when prescribed by noncardiologists. At all doses, patients taking the beta-blocker carvedilol have a lower incidence of death and HF hospitalization than those discontinuing it, regardless of physician type in the community setting.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Carbazóis/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Propanolaminas/administração & dosagem , Idoso , Carvedilol , Redes Comunitárias/estatística & dados numéricos , Esquema de Medicação , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Insuficiência Cardíaca/classificação , Insuficiência Cardíaca/mortalidade , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Taxa de Sobrevida , Estados Unidos
20.
Am Heart J ; 154(5): 861-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17967591

RESUMO

BACKGROUND: We determined whether low-dose oral enoximone could wean patients with ultra-advanced heart failure (UA-HF) from intravenous (i.v.) inotropic support. Chronic parenteral inotropic therapy in UA-HF is costly and requires an indwelling catheter. An effective and safe oral inotrope would have value. METHODS: In this placebo-controlled study, 201 subjects with UA-HF requiring i.v. inotropic therapy were randomized to enoximone or placebo. Subjects receiving intermittent i.v. inotropes were administered study medication of 25 or 50 mg 3 times a day (tid). Subjects receiving continuous i.v. inotropes were administered 50 or 75 mg tid for 1 week, which was reduced to 25 or 50 mg tid. The ability of subjects to remain alive and free of inotropic therapy was assessed for up to 182 days. RESULTS: Thirty days after weaning, 51 (51%) subjects on placebo and 62 (61.4%) subjects in the enoximone group were alive and free of i.v. inotropic therapy (unadjusted primary end point P = 0.14, adjusted for etiology P = .17). At 60 days, the wean rate was 30% in the placebo group and 46.5% in the enoximone group (unadjusted P = .016) Kaplan-Meier curves demonstrated a trend toward a decrease in the time to death or reinitiation of i.v. inotropic therapy over the 182-day study period (hazard ratio 0.76 [95% CI 0.55-1.04]) and a reduction at 60 days (0.62 [95% CI 0.43-0.89], P = .009) and 90 days (0.69 [95% CI 0.49-0.97], P = .031) after weaning in the enoximone group. CONCLUSIONS: Although there was no benefit over placebo in weaning patients from i.v. inotropes from 0 to 30 days, the EMOTE data suggest that low-dose oral enoximone can be used to wean a modest percentage of subjects from i.v. inotropic support for up to 90 days after initiation of therapy.


Assuntos
Cardiotônicos/administração & dosagem , Enoximona/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Contração Miocárdica/efeitos dos fármacos , Administração Oral , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologia , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia
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