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1.
Open Heart ; 7(2)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33020258

RESUMO

BACKGROUND: Cardiac involvement with COVID-19 is increasingly being recognised. Clinical characteristics and outcomes of patients with COVID-19 complicated by secondary Takotsubo cardiomyopathy (TC) is poorly understood. METHODS: This retrospective case series was conducted between March and April 2020 at four hospitals of Steward Health Care Network of Massachusetts, USA. Seven patients out of 169 who had echocardiogram were identified to have features of TC. Demographic, clinical, laboratory, management and outcome were gathered from their electronic medical records. We also reviewed all the published cases of COVID-19 and TC in the literature to recognise their common clinical characteristics, risk factors and outcomes. RESULTS: In our series of seven patients, three typical, two inverted, one biventricular and one global TC were recognised. Three were females and four were males. The mean age was 71±11 years. In-hospital death was observed in 57% of patients. Patients who belonged to the high-risk group and had high-risk echocardiographic features in our series had a 100% mortality rate. CONCLUSIONS: COVID-19 complicated by TC has a high mortality rate. Early identification of patients with COVID-19 who are at higher risk for developing secondary TC is important for the prevention of complications, and thus improved outcomes.


Assuntos
Causas de Morte , Infecções por Coronavirus/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Cardiomiopatia de Takotsubo/epidemiologia , Distribuição por Idade , Idoso , Estudos de Coortes , Comorbidade , Infecções por Coronavirus/diagnóstico , Ecocardiografia/métodos , Eletrocardiografia/métodos , Feminino , Coração Auxiliar , Mortalidade Hospitalar/tendências , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Prevalência , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Distribuição por Sexo , Cardiomiopatia de Takotsubo/terapia
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2589-2593, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018536

RESUMO

Left ventricular assist devices (LVADs) are used to treat patients with severe (New York Heart Association class IV) heart failure. Thrombosis and bleeding are severe LVAD-related complications; thus, an effective anticoagulation regimen is crucial for successful postoperative management. The CH-VAD™ (CH Biomedical, Inc.) is a small, implantable, full-support (>5 L/min) LVAD with a centrifugal flow pump that has a fully magnetically levitated rotor, which confers superior hemocompatibility. In this study, the CH-VAD™ was implanted in two calves to evaluate its hemocompatibility and to establish an anticoagulation regimen for future GLP (good laboratory practice) studies. Heparin infusion was used during the surgery, and during postoperative management, the proper dosage of warfarin was given orally to maintain an international normalized ratio (INR) between 2.0 and 3.0. Pump performance, animal condition, and hematology results were recorded throughout the study (approximately 60 days). The results show that under the established anticoagulation regimen, the CH-VAD™ was well tolerated in the bovine model, with no significant thrombus or thromboembolic lesion formation in distal end organs. Low plasma free hemoglobin levels suggest that the device did not cause hemolysis. These results and the experience gained pave the way for future GLP studies.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Trombose , Animais , Bovinos , Hemodinâmica , Humanos , Varfarina
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2662-2666, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018554

RESUMO

Left ventricular assist devices (LVADs) have increasingly been used clinically to treat heart failure patients. However, hemolysis, pump thrombosis, infection and bleeding still persist as major limitations of LVAD technology. Assessing LVAD hemocompatibility using a blood shear stress device (BSSD) has clear advantages, as the BSSD could provide a better experimental platform to develop reliable, quantifiable blood trauma assays to perform iterative testing of LVAD designs. In this study, a BSSD was proposed with short blood exposure time and no seals or contact bearings to reduce blood trauma caused by the test platform. Enlarged air-gap drive motor in BSSD is essential to avoid high shear stress; however, it would significantly reduce the motor torque, which may result in inadequate force to drive the entire system. In order to evaluate and optimize the drive motor air-gap to ensure adequate motor torque as well as acceptable range for blood exposure time and shear stress, a numerical brushless DC (BLDC) motor model was established using finite element method (FEM) in numerical simulation software COMSOL. The model was first validated by the experimental results. Then numerical model with different air-gap was evaluated on the torque and speed constant changes. In the end, two equations were generated based on the curves derived from the torque and speed constant calculations. Determining these relationships between motor performance and motor air-gap will facilitate the development of an appropriate BLDC motor size for the BSSD, considering the design limitations in our future work.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Animais , Hemólise , Humanos , Estresse Mecânico , Torque
4.
Circ Heart Fail ; 13(9): e007516, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32894988

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic imposed severe restrictions on traditional methods of patient care. During the pandemic, the heart failure program at New York-Presbyterian Hospital in New York, NY rapidly and comprehensively transitioned its care delivery model and administrative organization to conform to a new healthcare environment while still providing high-quality care to a large cohort of patients with heart failure, heart transplantation, and left ventricular assist device. In addition to the widespread adoption of telehealth, our program restructured outpatient care, initiating a shared clinic model and introducing a comprehensive remote monitoring program to manage patients with heart failure and heart transplant. All conferences, including administrative meetings, support groups, and educational seminars were converted to teleconferencing platforms. Following the peak of COVID-19, many of the new changes have been maintained, and the program structure will be permanently altered as a lasting effect of this pandemic. In this article, we review the details of our program's transition in the face of COVID-19 and highlight the programmatic changes that will endure.


Assuntos
Cardiologia/organização & administração , Infecções por Coronavirus/epidemiologia , Assistência à Saúde/organização & administração , Insuficiência Cardíaca/terapia , Pneumonia Viral/epidemiologia , Telemedicina/organização & administração , Planejamento Antecipado de Cuidados , Assistência Ambulatorial/organização & administração , Betacoronavirus , Transplante de Coração , Coração Auxiliar , Humanos , Cidade de Nova Iorque/epidemiologia , Profissionais de Enfermagem , Pandemias , Médicos , Papel Profissional , Grupos de Autoajuda , Telecomunicações , Centros de Atenção Terciária/organização & administração , Comunicação por Videoconferência
6.
Artif. organs ; 44(8): 797-802, Aug. 2020. ilus., graf.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1121435

RESUMO

Congestive heart failure is a pathology of global incidence that affects millions of people worldwide. When the heart weakens and fails to pump blood at physiological rates commensurate with the requirements of tissues, two main alternatives are cardiac transplant and ventricular assist devices (VADs). This article presents the design strategy for development of a customized VAD electromagnetic actuator. Electromagnetic actuator is a brushless direct current motor customized to drive the pump impeller by permanent magnets located in rotor­stator coupling. In this case, ceramic pivot bearings support the VAD impeller. Electronic circuitry controls rotation switching current in stator coils. The proposed methodology consisted of analytical numerical design, tridimensional computational modeling, numerical simulations using Maxwell software, actuator prototyping, and validation in the dynamometer. The axial flow actuator was chosen by its size and high power density compared to the radial flow type. First step consisted of estimating the required torque to drive the pump. Torque was estimated at 2100 rpm and mean current of 0.5 A. Numerical analysis using finite element method mapped vectors and fields to build stator coils and actuator assemblage. After tests in the dynamometer, experimental results were compared with numerical simulation and validated the proposed model. In conclusion, the proposed methodology for designing of VAD electromechanical actuator was considered satisfactory in terms of data consistency, feasibility, and reliability.


Assuntos
Materiais Biocompatíveis , Coração Auxiliar , Desenho de Equipamento
7.
Artif. organs ; 44(8): 785-796, Aug. 2020. gráfico, ilustração, tabela
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1103514

RESUMO

Left ventricular assist devices (LVADs) have been used as a bridge to transplantation or as destination therapy to treat patients with heart failure (HF). The inability of control strategy to respond automatically to changes in hemodynamic conditions can impact the patients' quality of life. The developed control system/algorithm consists of a control system that harmoniously adjusts pump speed without additional sensors, considering the patient's clinical condition and his physical activity. The control system consists of three layers: (a) Actuator speed control; (b) LVAD flow control (FwC); and (c) Fuzzy control system (FzC), with the input variables: heart rate (HR), mean arterial pressure (MAP), minimum pump flow, level of physical activity (data from patient), and clinical condition (data from physician, INTERMACS profile). FzC output is the set point for the second LVAD control schemer (FwC) which in turn adjusts the speed. Pump flow, MAP, and HR are estimated from actuator drive parameters (speed and power). Evaluation of control was performed using a centrifugal blood pump in a hybrid cardiovascular simulator, where the left heart function is the mechanical model and right heart function is the computational model. The control system was able to maintain MAP and cardiac output in the physiological level, even under variation of EF. Apart from this, also the rotational pump speed is adjusted following the simulated clinical condition. No backflow from the aorta in the ventricle occurred through LVAD during tests. The control algorithm results were considered satisfactory for simulations, but it still should be confirmed during in vivo tests.


Assuntos
Sangue , Técnicas In Vitro , Algoritmos , Coração Auxiliar
8.
PLoS One ; 15(8): e0238046, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833995

RESUMO

BACKGROUND: There are limited data on the complications with a percutaneous left ventricular assist device (pLVAD) vs. intra-aortic balloon pump (IABP) in acute myocardial infarction-cardiogenic shock (AMI-CS). OBJECTIVE: To assess the trends, rates and predictors of complications. METHODS: Using a 17-year AMI-CS population from the National Inpatient Sample, AMI-CS admissions receiving pLVAD and IABP support were evaluated for vascular, lower limb amputation, hematologic, neurologic and acute kidney injury (AKI) complications. In-hospital mortality, hospitalization costs and length of stay in pLVAD and IABP cohorts with complications was studied. RESULTS: Of 168,645 admissions, 7,855 (4.7%) receiving pLVAD support. The pLVAD cohort had higher comorbidity, cardiac arrest (36.1% vs. 29.7%) and non-cardiac organ failure (74.7% vs. 56.9%) rates. Complications were higher in pLVAD compared to IABP cohort-overall 69.0% vs. 54.7%; vascular 3.8% vs. 2.1%; lower limb amputation 0.3% vs. 0.3%; hematologic 36.0% vs. 27.7%; neurologic 4.9% vs. 3.5% and AKI 55.4% vs. 39.1% (all p<0.001 except for amputation). Non-White race, higher comorbidity, organ failure, and extracorporeal membrane oxygen use were predictors of complications for both cohorts. The pLVAD cohort with complications had higher in-hospital mortality (45.5% vs. 33.1%; adjusted odds ratio 1.65 [95% confidence interval 1.55-1.75]), shorter duration of hospital stay, and higher hospitalization costs compared to the IABP cohort with complications (all p<0.001). These results were consistent in propensity-matched pairs. CONCLUSIONS: AMI-CS admissions receiving pLVAD had higher rates of complications compared to the IABP, with worse in-hospital outcomes in the cohort with complications.


Assuntos
Coração Auxiliar/efeitos adversos , Balão Intra-Aórtico/efeitos adversos , Infarto do Miocárdio/complicações , Complicações Pós-Operatórias/etiologia , Choque Cardiogênico/complicações , Choque Cardiogênico/cirurgia , Doença Aguda , Idoso , Feminino , Hospitais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Choque Cardiogênico/terapia
11.
Int Heart J ; 61(4): 848-850, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32728003

RESUMO

Right ventricular (RV) dysfunction may occur after cardiac surgery and it is not rare after corrective repair of tetralogy of Fallot (TOF). If traditional treatments with volume management, infusion of inotropic agents, and use of pulmonary vasodilators cannot stabilize the patient, extracorporeal membrane oxygenation (ECMO) or a ventricular assist device (VAD) will be considered as the last resort. Here, we report a young infant patient with RV failure after corrective repair of TOF and without closure of an atrial septal defect (ASD), who was rescued by veno-venous (VV) -ECMO.


Assuntos
Septo Interatrial/cirurgia , Oxigenação por Membrana Extracorpórea/métodos , Tetralogia de Fallot/cirurgia , Disfunção Ventricular Direita/terapia , Assistência ao Convalescente , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ecocardiografia/métodos , Insuficiência Cardíaca/fisiopatologia , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interatrial/fisiopatologia , Comunicação Interatrial/cirurgia , Coração Auxiliar , Humanos , Lactente , Masculino , Dispositivo para Oclusão Septal/normas , Tetralogia de Fallot/diagnóstico por imagem , Resultado do Tratamento
12.
Lancet ; 396(10245): 199-212, 2020 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-32682486

RESUMO

Cardiogenic shock can occur due to acute ischaemic or non-ischaemic cardiac events, or from progression of long-standing underlying heart disease. When addressing the cause of underlying disease, the management of cardiogenic shock consists of vasopressors and inotropes; however, these agents can increase myocardial oxygen consumption, impair tissue perfusion, and are frequently ineffective. An alternative approach is to temporarily augment cardiac output using mechanical devices. The use of these devices-known as temporary circulatory support systems-has increased substantially in recent years, despite being expensive, resource intensive, associated with major complications, and lacking high-quality evidence to support their use. This Review summarises the physiological basis underlying the use of temporary circulatory support for cardiogenic shock, reviews the evidence informing indications and contraindications, addresses ethical considerations, and highlights the need for further research.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Balão Intra-Aórtico/métodos , Choque Cardiogênico/terapia , Oxigenação por Membrana Extracorpórea/efeitos adversos , Coração Auxiliar/efeitos adversos , Humanos , Balão Intra-Aórtico/efeitos adversos
13.
JACC Heart Fail ; 8(10): 789-799, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32641226

RESUMO

The PARADIGM-HF (Prospective Comparison of Angiotensin II Receptor Blocker Neprilysin Inhibitor With Angiotensin-Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure) trial reported that sacubitril/valsartan (S/V), an angiotensin receptor-neprilysin inhibitor, significantly reduced mortality and heart failure (HF) hospitalization in HF patients with a reduced ejection fraction (HFrEF). However, fewer than 1% of patients in the PARADIGM-HF study had New York Heart Association (NYHA) functional class IV symptoms. Accordingly, data that informed the use of S/V among patients with advanced HF were limited. The LIFE (LCZ696 in Hospitalized Advanced Heart Failure) study was a 24-week prospective, multicenter, double-blinded, double-dummy, active comparator trial that compared the safety, efficacy, and tolerability of S/V with those of valsartan in patients with advanced HFrEF. The trial planned to randomize 400 patients ≥18 years of age with advanced HF, defined as an EF ≤35%, New York Heart Association functional class IV symptoms, elevated natriuretic peptide concentration (B-type natriuretic peptide [BNP] ≥250 pg/ml or N-terminal pro-B-type natriuretic peptide [NT-proBNP] ≥800 pg/ml), and ≥1 objective finding of advanced HF. Following a 3- to 7-day open label run-in period with S/V (24 mg/26 mg twice daily), patients were randomized 1:1 to S/V titrated to 97 mg/103 mg twice daily versus 160 mg of V twice daily. The primary endpoint was the proportional change from baseline in the area under the curve for NT-proBNP levels measured through week 24. Secondary and tertiary endpoints included clinical outcomes and safety and tolerability. Because of the COVID-19 pandemic, enrollment in the LIFE trial was stopped prematurely to ensure patient safety and data integrity. The primary analysis consists of the first 335 randomized patients whose clinical follow-up examination results were not severely impacted by COVID-19. (Entresto [LCZ696] in Advanced Heart Failure [LIFE STUDY] [HFN-LIFE]; NCT02816736).


Assuntos
Aminobutiratos/uso terapêutico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Tetrazóis/uso terapêutico , Betacoronavirus , Cardiotônicos/uso terapêutico , Infecções por Coronavirus , Relação Dose-Resposta a Droga , Método Duplo-Cego , Término Precoce de Ensaios Clínicos , Taxa de Filtração Glomerular , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Transplante de Coração , Coração Auxiliar , Hospitalização/estatística & dados numéricos , Humanos , Hipotensão/induzido quimicamente , Peptídeo Natriurético Encefálico/metabolismo , Pandemias , Fragmentos de Peptídeos/metabolismo , Pneumonia Viral , Volume Sistólico
14.
Rev Med Chil ; 148(3): 409-413, 2020 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-32730388

RESUMO

We report a 55-year-old woman with a history of hypothyroidism and type 2 diabetes mellitus who consulted at the emergency room because of intermittent oppressive chest discomfort. At admission, electrocardiogram showed a complete atrioventricular block. A transthoracic echocardiogram disclosed severe left ventricular dysfunction. The patient developed cardiogenic shock that required the installation of the Impella system. An emergency coronary angiography showed an ostial occlusion of the anterior descending artery. Despite successful primary angioplasty, she persisted with refractory shock and progressive hypoxemia. A concomitant connection to the extracorporeal membrane oxygenation system (ECMO) was decided. The support of both devices allowed the stabilization of the patient and the improvement of perfusion parameters.


Assuntos
Coração Auxiliar , Choque Cardiogênico/terapia , Disfunção Ventricular Esquerda , Diabetes Mellitus Tipo 2 , Oxigenação por Membrana Extracorpórea , Feminino , Humanos , Pessoa de Meia-Idade
17.
Arch Cardiovasc Dis ; 113(6-7): 461-472, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32653240

RESUMO

Heart failure affects more than 30 million people worldwide and its prevalence is constantly rising. In 2020, heart transplantation is the only curative treatment, but left ventricular assistance devices (LVADs) are fully integrated into the decision algorithm for management of patients with advanced heart failure, with more than 20,000 devices implanted worldwide in the last decade. Intended to support cardiac output, LVADs remove the blood from the left ventricle and eject it into the proximal aorta. Whereas first-generation LVADs were pulsatile, second- and third-generation LVADs are more reliable, but create a laminar flow, with reduced (or absent) blood flow pulsatility. Concomitantly, several new adverse events, some of them lethal, appeared when continuous-flow LVADs started to be implanted, including acquired von Willebrand disease, gastrointestinal bleeding and aortic valve fusion or regurgitation. This review aims to apply models describing pulsatility (such as the Windkessel effect applied by Frank, Guyton's continuity model of venous return and Sunagawa's left ventricular-arterial coupling) to LVADs, to better understand the physiopathology in patients using continuous-flow devices. This review also covers the means of exploring pulsatility and adverse events associated with a reduction in pulsatility, as well as the possible ways for restoring pulsatility in patients implanted with an LVAD.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Hemodinâmica , Implantação de Prótese/instrumentação , Função Ventricular Esquerda , Animais , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Modelos Cardiovasculares , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Implantação de Prótese/mortalidade , Fluxo Pulsátil , Recuperação de Função Fisiológica , Fatores de Risco , Resultado do Tratamento
18.
J Card Surg ; 35(8): 1778-1786, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32667067

RESUMO

BACKGROUND: Ventricular assist devices (VADs) are commonly employed as a bridge to transplantation for heart failure. The full effects of VADs on transplantation rates are not fully understood. We sought to compare transplantation rates stratified by age and VAD status. METHODS: Using the Organ Procurement and Transplantation Network (OPTN) database, we investigated the impact of age and VAD status on heart allocation rates among all transplant-eligible patients from January 2005 to September 2018. Patients were grouped based on the presence (+) or absence (-) of a VAD as well as age (<45, 45-65, and >65 years). Demographics were compared with a multivariate competing risk analysis that yielded risk-adjusted subdistribution hazard ratios (SHR). RESULTS: Among the 50 602 total waitlist candidates, 18 271 patients with a VAD had higher rates of diabetes and cerebrovascular disease at waitlist entry. Multivariate analysis found statistically significant lower rates of transplantation for all (+)VAD groups compared with age-matched (-)VAD counterparts, with the 45- to 65-year-old (+)VAD group having the lowest transplantation rate (SHR = 0.62; P < .0005). Among (-)VAD patients, transplantation rates increased with increase in age. CONCLUSIONS: There is a statistically significant reduced rate of transplantation for patients with a VAD compared with those without a VAD, with the lowest rate among those of ages 45 to 65 years with a VAD. The increasing prevalence of this demographic and the deprioritization of VADs in the new heart allocation criteria have the potential to further exacerbate this difference.


Assuntos
Transplante de Coração , Coração Auxiliar , Listas de Espera , Idoso , Feminino , Transplante de Coração/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada
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