Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Cardiovasc Electrophysiol ; 30(2): 183-192, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30516301

RESUMO

INTRODUCTION: Ventricular arrhythmias (VA) after left ventricular assist device (LVAD) placement are associated with increased morbidity and mortality. We sought to assess epicardial voltage characteristics at the time of LVAD implantation and investigate relationships between scar burden and postimplant VA. METHODS AND RESULTS: Consecutive patients underwent open chest epicardial electroanatomic mapping immediately before LVAD implantation. Areas of low voltage and sites with local abnormal potentials were identified. Patients were followed prospectively for postimplant VA and clinical outcomes. Between 2015 and 2017, 36 patients underwent high-density intraoperative epicardial voltage mapping; 15 had complete maps suitable for analysis. Mapping required a median of 11.8 (interquartile range [IQR], 8.5-12.7) minutes, with a median of 2650 (IQR, 2139-3191) points sampled per patient. Over a median follow-up of 311 (IQR, 168-469) postoperative days, four patients (27%) experienced sustained VA. Patients with postimplant VA were more likely to have had preimplant implantable cardioverter defibrillator shocks (100% vs 27%; P = 0.03), ventricular tachycardia storm (75% vs 9%; P = 0.03), and lower ejection fraction (13.5 vs 19.0%, P = 0.05). Patients with postimplant VA also had a significantly higher burden of epicardial low bipolar voltage points: 55.4% vs 24.9% of points were less than 0.5 mV (P = 0.01), and 88.9% vs 63.7% of points less than 1.5 mV (P = 0.004). CONCLUSIONS: Intraoperative high-density epicardial mapping during LVAD implantation is safe and efficient, facilitating characterization of a potentially arrhythmogenic substrate. An increased burden of the epicardial scar may be associated with a higher incidence of postimplant VA. The role of empiric intraoperative epicardial ablation to mitigate risk of postimplant VA requires further study.


Assuntos
Arritmias Cardíacas/etiologia , Cicatriz/complicações , Insuficiência Cardíaca/terapia , Coração Auxiliar , Pericárdio/fisiopatologia , Implantação de Prótese/efeitos adversos , Implantação de Prótese/instrumentação , Função Ventricular Esquerda , Potenciais de Ação , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Cicatriz/diagnóstico , Cicatriz/fisiopatologia , Mapeamento Epicárdico , Estudos de Viabilidade , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Pericárdio/patologia , Estudos Prospectivos , Desenho de Prótese , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
3.
Biosensors (Basel) ; 14(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38785727

RESUMO

Heart failure represents a primary cause of hospitalization and mortality in both developed and developing countries, often necessitating heart transplantation as the only viable recovery path. Despite advances in transplantation medicine, organ rejection remains a significant post-operative challenge, traditionally monitored through invasive endomyocardial biopsies (EMB). This study introduces a rapid prototyping approach to organ rejection monitoring via a sensor-integrated flexible patch, employing electrical impedance spectroscopy (EIS) for the non-invasive, continuous assessment of resistive and capacitive changes indicative of tissue rejection processes. Utilizing titanium-dioxide-coated electrodes for contactless impedance sensing, this method aims to mitigate the limitations associated with EMB, including procedural risks and the psychological burden on patients. The biosensor's design features, including electrode passivation and three-dimensional microelectrode protrusions, facilitate effective monitoring of cardiac rejection by aligning with the heart's curvature and responding to muscle contractions. Evaluation of sensor performance utilized SPICE simulations, scanning electron microscopy, and cyclic voltammetry, alongside experimental validation using chicken heart tissue to simulate healthy and rejected states. The study highlights the potential of EIS in reducing the need for invasive biopsy procedures and offering a promising avenue for early detection and monitoring of organ rejection, with implications for patient care and healthcare resource utilization.


Assuntos
Espectroscopia Dielétrica , Humanos , Transplante de Coração , Técnicas Biossensoriais , Rejeição de Enxerto/diagnóstico , Animais , Galinhas , Monitorização Fisiológica
4.
JACC Heart Fail ; 11(8 Pt 1): 865-878, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37269258

RESUMO

Late right heart failure (RHF) is increasingly recognized in patients with long-term left ventricular assist device (LVAD) support and is associated with decreased survival and increased incidence of adverse events such as gastrointestinal bleeding and stroke. Progression of right ventricular (RV) dysfunction to clinical syndrome of late RHF in patients supported with LVAD is dependent on the severity of pre-existing RV dysfunction, persistent or worsening left- or right-sided valvular heart disease, pulmonary hypertension, inadequate or excessive left ventricular unloading, and/or progression of the underlying cardiac disease. RHF likely represents a continuum of risk with early presentation and progression to late RHF. However, de novo RHF develops in a subset of patients leading to increased diuretic requirement, arrhythmias, renal and hepatic dysfunction, and heart failure hospitalizations. The distinction between isolated late RHF and RHF due to left-sided contributions is lacking in registry studies and should be the focus of future registry data collection. Potential management strategies include optimization of RV preload and afterload, neurohormonal blockade, LVAD speed optimization, and treatment of concomitant valvular disease. In this review, the authors discuss definition, pathophysiology, prevention, and management of late RHF.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Disfunção Ventricular Direita , Humanos , Coração Auxiliar/efeitos adversos , Estudos Retrospectivos , Sistema de Registros , Ventrículos do Coração , Disfunção Ventricular Direita/epidemiologia
5.
Artif Organs ; 36(5): 470-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22171892

RESUMO

In heart failure, diastolic dysfunction is responsible for about 50% of the cases, with higher prevalence in women and elderly persons and contributing similarly to mortality as systolic dysfunction. Whereas the cardiac systolic diagnostics in ventricular assist device patients from pump parameters have been investigated by several groups, the diastolic behavior has been barely discussed. This study focuses on the determination of ventricular relaxation during early diastole in rotary blood pump (RBP) recipients. In conventional cardiology, relaxation is usually evaluated by the minimum rate and the time constant of left ventricular pressure decrease, dP/dt(min) and τ(P) . Two new analogous indices derived from the pump flow waveform were investigated in this study: the minimum rate and the time constant of pump flow decrease, dQ/dt(min) and τ(Q) . The correspondence between the indices was investigated in a numerical simulation of the assisted circulation for different ventricular relaxation states (τ(P) ranging from 24 to 68 ms) and two RBP models characterized by linear and nonlinear pressure-flow characteristics. dQ/dt(min) and τ(Q) always correlated with the dP/dt(min) and τ(P) , respectively (r>0.97). These relationships were influenced by the nonlinear pump characteristics during partial support and by the pump speed during full support. To minimize these influences, simulation results suggest the evaluation of dQ/dt(min) and τ(Q) at a pump speed that corresponds to the borderline between partial and full support. In conclusion, at least in simulation, relaxation can be derived from pump data. This noninvasively accessible information could contribute to a continuous estimation of the remaining cardiac function and its eventual recovery.


Assuntos
Diástole , Coração Auxiliar , Modelos Cardiovasculares , Pressão Ventricular , Simulação por Computador , Humanos
6.
Artif Organs ; 36(8): 691-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22882439

RESUMO

Estimation of instantaneous flow in rotary blood pumps (RBPs) is important for monitoring the interaction between heart and pump and eventually the ventricular function. Our group has reported an algorithm to derive ventricular contractility based on the maximum time derivative (dQ/dt(max) as a substitute for ventricular dP/dt(max) ) and pulsatility of measured flow signals. However, in RBPs used clinically, flow is estimated with a bandwidth too low to determine dQ/dt(max) in the case of improving heart function. The aim of this study was to develop a flow estimator for a centrifugal pump with bandwidth sufficient to provide noninvasive cardiac diagnostics. The new estimator is based on both static and dynamic properties of the brushless DC motor. An in vitro setup was employed to identify the performance of pump and motor up to 20 Hz. The algorithm was validated using physiological ventricular and arterial pressure waveforms in a mock loop which simulated different contractilities (dP/dt(max) 600 to 2300 mm Hg/s), pump speeds (2 to 4 krpm), and fluid viscosities (2 to 4 mPa·s). The mathematically estimated pump flow data were then compared to the datasets measured in the mock loop for different variable combinations (flow ranging from 2.5 to 7 L/min, pulsatility from 3.5 to 6 L/min, dQ/dt(max) from 15 to 60 L/min/s). Transfer function analysis showed that the developed algorithm could estimate the flow waveform with a bandwidth up to 15 Hz (±2 dB). The mean difference between the estimated and measured average flows was +0.06 ± 0.31 L/min and for the flow pulsatilities -0.27 ± 0.2 L/min. Detection of dQ/dt(max) was possible up to a dP/dt(max) level of 2300 mm Hg/s. In conclusion, a flow estimator with sufficient frequency bandwidth and accuracy to allow determination of changes in ventricular contractility even in the case of improving heart function was developed.


Assuntos
Algoritmos , Coração Auxiliar , Modelos Cardiovasculares , Velocidade do Fluxo Sanguíneo , Desenho de Equipamento , Humanos , Contração Miocárdica , Fluxo Pulsátil , Função Ventricular
7.
Lasers Surg Med ; 44(9): 705-11, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23007916

RESUMO

BACKGROUND AND OBJECTIVE: As low-level laser irradiation (LLLI) seems to induce vasodilation besides many other known biological effects, LLLI has been increasingly used in therapy of medical conditions with various irradiation parameters. The aim of this study was to investigate the effect of LLLI on photorelaxation of human coronary and internal thoracic arteries (ITA). MATERIALS AND METHODS: Thirty vessel segments of ITA used for routine coronary artery bypass grafting as well as left anterior descending coronary arteries (LAD) of patients undergoing cardiac transplantation were cut into 4-mm rings stored in a modified Krebs-Henseleit solution and evaluated in a myograph. Both types of vessel segments were irradiated by a semiconductor non-thermal GaAs diode laser operating at a wavelength of 680 nm. After precontraction with thromboxane agonist U44619, respective relaxation responses were evaluated and compared to pharmacological dilatation induced by substance P. RESULTS: Mean pharmacological vasodilation by substance P was 22.6 ± 3.3%, 12.8 ± 1.4%, and 20.4 ± 3.2% in macroscopic healthy LAD, LAD with atheromatous plaque, and ITA, respectively. Average photorelaxation induced by LLLI was 16.5 ± 2.0%, 1.9 ± 1.7%, and 6.8 ± 4.7%, accordingly. Vasodilatatory responses induced either by substance P or administration of LLLI were significantly decreased in LAD with atheromatous plaque (P < 0.0001). Vasospasms of ITA segments occurring during experiments could be abandoned when LLLI was administered. CONCLUSION: Macroscopic healthy LAD exposed to LLLI revealed significant photorelaxation. With the administration of LLLI, 73% of the maximal obtainable effect by an endothelium-dependent vasodilator could be reached. Furthermore, LLLI has the potential to overcome vasospasms of ITA.


Assuntos
Vasos Coronários/efeitos da radiação , Lasers Semicondutores , Artéria Torácica Interna/efeitos da radiação , Vasoconstrição/efeitos da radiação , Vasodilatação/efeitos da radiação , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Idoso , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Artéria Torácica Interna/efeitos dos fármacos , Artéria Torácica Interna/fisiologia , Pessoa de Meia-Idade , Neurotransmissores/farmacologia , Substância P/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos
8.
ASAIO J ; 68(1): 14-20, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34524147

RESUMO

The study aim was to examine the impact time in therapeutic range (TTR, International Normalized Ratio [INR] 2.0-3.0) has on survival and adverse events in patients receiving the HeartWare HVAD System in the ENDURANCE and ENDURANCE Supplemental Trials. Evaluable subjects (n = 495) had >1 INR value recorded 1-24 months postimplant and were categorized as: low TTR (10-39%), moderate TTR (40-69%), and high TTR (≥70%). Baseline characteristics, adverse events, and survival were analyzed. Low TTR patients experienced higher rates of major bleeding (1.69 vs. 0.54 events per patient year [EPPY]; p < 0.001), GI bleeding (1.22 vs. 0.38 EPPY; p < 0.001), stroke (0.47 vs. 0.17 EPPY; p < 0.001), thrombus requiring exchange (0.05 vs. 0.01 EPPY; p = 0.02), infection (1.44 vs. 0.69 EPPY; p < 0.001), and renal dysfunction (0.23 vs. 0.05 EPPY; p < 0.001) compared with high TTR. Moderate TTR had higher rates of major bleeding (0.75 vs. 0.54 EPPY; p < 0.001), thrombus requiring exchange (0.05 vs. 0.01 EPPY; p = 0.007), cardiac arrhythmia (0.32 vs. 0.24 EPPY; p = 0.04), and infection (0.90 vs. 0.69 EPPY; p = 0.001) compared with high TTR. Two year survival was greater among moderate and high versus low cohorts (Log-rank p = 0.001). The significant reduction in morbidity and mortality in destination therapy (DT) HVAD patients with well-controlled TTR (≥70%) emphasizes the importance of vigilant anticoagulation management.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Anticoagulantes , Hemorragia/etiologia , Humanos , Coeficiente Internacional Normatizado , Resultado do Tratamento
9.
Artif Organs ; 35(8): 773-80, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21843292

RESUMO

Ventricular assist devices (VADs) are now increasingly used to prolong the lives of end-stage heart failure patients. These patients vary greatly in age, alertness, activity, and home environment. In daily routine, but especially in emergencies or in conjunction with non-VAD-correlated diseases, the untrained, intuitive use and application of VAD peripherals by relatives, laypersons, and paramedics becomes important. Correct intuitive use may be a matter of life and death. The aim of this study was to evaluate the intuitive usability of these systems and to identify key features needed to optimize intuitive use. Paramedics (n=96) were confronted with a simulated emergency situation involving VAD peripherals mounted on a dummy. Three conditions were simulated: the VAD disconnected from its power source (n=44); both VAD batteries empty (n=44); and a discharged VAD battery mistakenly connected in place of a charged one (n=8). Two VAD systems were assessed: the Heartware HVAD and the Thoratec HeartMate II. An appropriate emergency card developed by our center was available in each case. Actions were videotaped, response times were measured, and a standardized questionnaire was completed after the simulation. The problem was solved by 71% of the participants (HVAD 83%, HMII 60%) with 87% using the emergency card. Only 4% could solve the problem without. Cardiac massage, which was unnecessary, was started by 44%, while 18% complained about unnecessarily difficult conditions (e.g., irritation from the acoustic alarm, complexity of the emergency card, error-prone procedures). Better component labeling (e.g., displays, control elements, connectors) was recommended by 56%. A thoroughly color-coded connection system was especially desired. Cable- and connector-related difficulties were reported by 23%. The study indicated that VAD systems should be self-explaining, with clear labeling of components and connectors, that a clearer emergency card is pivotal and that similar basic handling and emergency procedures for all VAD types would be desirable.


Assuntos
Tratamento de Emergência/instrumentação , Coração Auxiliar , Adulto , Emergências , Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Circ Heart Fail ; 14(4): e006912, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33866829

RESUMO

BACKGROUND: The LATERAL trial validated the safety and efficacy of the thoracotomy approach for implantation of the HeartWare HVAD System, leading to Food and Drug Administration approval. We sought to analyze 24-month adverse event (AE) rates, including a temporal analysis of the risk profile, associated with the thoracotomy approach for the HVAD system. METHODS: AEs from the LATERAL trial were evaluated over 2 years postimplant. Data was obtained from the Interagency Registry for Mechanically Assisted Circulatory Support database for 144 enrolled United States and Canadian patients. Temporal AE profiles were expressed as events per patient year. RESULTS: During 162.5 patient years of support, there were 25 driveline infections (0.15 events per patient year), 50 gastrointestinal bleeds (0.31 events per patient year), and 21 strokes (0.13 events per patient year). Longitudinal AE analysis at follow-up intervals of <30 and 30 to 180 days, and 6 to 12 and 12 to 24 months revealed the highest AE rate at <30 days, with a decrease in total AEs within the first 6 months. After 6 months, most AE rates either stabilized or decreased through 2 years, including a 95% overall freedom from disabling stroke. CONCLUSIONS: Two-year follow-up of the LATERAL trial revealed a favorable morbidity profile in patients supported with the HVAD system, as AE rates were more likely to occur in the first 30 days postimplant, and overall AE rates were significantly reduced after 6 months. Importantly, 2-year freedom from disabling stroke was 95%. These data further support the improving AE profile of patients on long-term HVAD support. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02268942.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar/efeitos adversos , Toracotomia , Idoso , Canadá , Aprovação de Equipamentos , Feminino , Seguimentos , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Acidente Vascular Cerebral/etiologia , Estados Unidos , United States Food and Drug Administration
11.
Crit Care ; 14(2): 201, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20497611

RESUMO

Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Insuficiência Cardíaca/etiologia , Assistência Perioperatória/organização & administração , Guias de Prática Clínica como Assunto , Humanos , Valor Preditivo dos Testes , Prognóstico
12.
Ann Thorac Surg ; 110(5): 1512-1519, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32224242

RESUMO

BACKGROUND: Less invasive techniques for left ventricular assist device implantation have been increasingly prevalent over past years and have been associated with improved clinical outcomes. The procedural economic impact of these techniques remains unknown. We sought to study and report economic outcomes associated with the thoracotomy implantation approach. METHODS: The LATERAL clinical trial evaluated the safety and efficacy of the thoracotomy approach for implantation of the HeartWare centrifugal-flow ventricular assist device system (HVAD). We collected UB-04 forms in parallel to the trial, allowing analysis of index hospitalization costs. All charges were converted to costs using hospital-specific cost-to-charge ratios and were subsequently compared with Medicare cost data for the same period (2015-2016). Because thoracotomy implants were off-label for all left ventricular assist devices during that period, the Medicare cohort was assumed to consist predominately of traditional sternotomy patients. RESULTS: Thoracotomy patients demonstrated decreased costs compared with sternotomy patients during the index hospitalization. Mean total index hospitalization costs for thoracotomy were $204,107 per patient, corresponding to 21.6% reduction (P < .001) and $56,385 savings per procedure compared with sternotomy. Across almost all cost categories, thoracotomy implants were less costly. CONCLUSIONS: In LATERAL, a clinical trial evaluating the safety and efficacy of the thoracotomy approach for HVAD, costs were lower than those reported in Medicare patient claims occurring over the same period. Because Medicare data can be presumed to consist of predominately sternotomy procedures, thoracotomy appears less expensive than traditional sternotomy.


Assuntos
Custos e Análise de Custo , Coração Auxiliar , Implantação de Prótese/economia , Implantação de Prótese/métodos , Esternotomia/economia , Toracotomia/economia , Adulto , Idoso , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Medicare , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Estados Unidos
13.
IEEE J Biomed Health Inform ; 24(7): 1899-1906, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31940570

RESUMO

OBJECTIVE: Left ventricular assist devices (LVADs) fail in up to 10% of patients due to the development of pump thrombosis. Remote monitoring of patients with LVADs can enable early detection and, subsequently, treatment and prevention of pump thrombosis. We assessed whether acoustical signals measured on the chest of patients with LVADs, combined with machine learning algorithms, can be used for detecting pump thrombosis. METHODS: 13 centrifugal pump (HVAD) recipients were enrolled in the study. When hospitalized for suspected pump thrombosis, clinical data and acoustical recordings were obtained at admission, prior to and after administration of thrombolytic therapy, and every 24 hours until laboratory and pump parameters normalized. First, we selected the most important features among our feature set using LDH-based correlation analysis. Then using these features, we trained a logistic regression model and determined our decision threshold to differentiate between thrombosis and non-thrombosis episodes. RESULTS: Accuracy, sensitivity and precision were calculated to be 88.9%, 90.9% and 83.3%, respectively. When tested on the post-thrombolysis data, our algorithm suggested possible pump abnormalities that were not identified by the reference pump power or biomarker abnormalities. SIGNIFICANCE: We showed that the acoustical signatures of LVADs can be an index of mechanical deterioration and, when combined with machine learning algorithms, provide clinical decision support regarding the presence of pump thrombosis.


Assuntos
Ruídos Cardíacos/fisiologia , Coração Auxiliar/efeitos adversos , Processamento de Sinais Assistido por Computador , Trombose/diagnóstico , Acústica , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrografia do Som , Estetoscópios
15.
Artif Organs ; 33(1): 77-80, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19178445

RESUMO

Mechanical support offered by rotary pumps is increasingly used to assist the failing heart, although several questions concerning physiology remain. In this study, we sought to evaluate the effect of left-ventricular assist device (VAD) therapy on coronary hemodynamics, myocardial oxygen consumption, and pulmonary blood flow in sheep. We performed an acute experiment in 10 sheep to obtain invasively measured coronary perfusion data, as well as pressure and flow conditions under cardiovascular assistance. A DeBakey VAD (MicroMed Cardiovascular, Inc., Houston, TX, USA) was implanted, and systemic and coronary hemodynamic measurements were performed at defined baseline conditions and at five levels of assistance. Data were measured when the pump was clamped, as well as under minimum, maximum, and moderate levels of assistance, and in a pump-off condition where backflow occurs. Coronary flow at the different levels of support showed no significant impact of pump activity. The change from baseline ranged from -10.8% to +4.6% (not significant [n.s.]). In the pulmonary artery, we observed a consistent increase in flow up to +4.5% (n.s.) and a decrease in the pulmonary artery pressure down to -14.4% (P = 0.004). Myocardial oxygen consumption fell with increasing pump support down to -34.6% (P = 0.008). Left-ventricular pressure fell about 52.2% (P = 0.016) as support was increased. These results show that blood flow in the coronary arteries is not affected by flow changes imposed by rotary blood pumps. An undiminished coronary perfusion at falling oxygen consumption might contribute to cardiac recovery.


Assuntos
Circulação Coronária , Coração Auxiliar , Miocárdio/metabolismo , Consumo de Oxigênio , Animais , Hemodinâmica , Ovinos
16.
Artif Organs ; 33(9): 691-5, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19775260

RESUMO

The purpose of this study was the investigation of the usability and ergonomics of ventricular assist devices (VADs) in everyday usage. Patients with four different VAD types were observed. After implantation, instruction, and discharge from the hospital, the patients returned on a regular basis to the outpatient clinic, where the investigation took place. Data collection took place in two phases. In phase I home-released VAD patients were asked about perceived problems with the system at home. Additionally health-care professionals were interviewed to gather information on frequent VAD inconveniences and shortcomings. This inquiry resulted in a standardized self-assessment questionnaire and a manual skill test, which were performed in phase II by the whole collective (16 patients and ongoing). As a result, 38% of the patients disconnected parts of their system unintentionally at least once. All of them ascribed this problem to their own carelessness. Thirty-eight percent had to replace a cable. Seventy-five percent desired an additional cable strain relief. Thirty-eight percent suffered from rubbing of parts on the body. Sixty-three percent used a separate repository aside from the factory-provided transportation systems. The overall noise emission (pump, ventilators, and alarms) annoyed 56%; however, for 32% the alarm signals were too quiet to wake them up. No correlation between the assessed manual skills and the number of adverse events was found. To conclude, this preliminary study revealed considerable potential for improvements in the usability of ventricular assist systems.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Satisfação do Paciente , Autocuidado , Adulto , Idoso , Alarmes Clínicos , Qualidade de Produtos para o Consumidor , Fontes de Energia Elétrica , Desenho de Equipamento , Falha de Equipamento , Ergonomia , Feminino , Coração Auxiliar/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Destreza Motora , Projetos Piloto , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
17.
J Heart Lung Transplant ; 38(4): 344-351, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30945636

RESUMO

BACKGROUND: The HeartWare centrifugal-flow ventricular assist device system (HVAD) is a viable option for treatment of advanced heart failure. There is a growing trend toward the use of less invasive techniques in cardiac surgery, and the thoracotomy technique for HVAD implantation may provide benefits not available with conventional approaches. METHODS: The LATERAL trial is a multicenter, prospective, non-randomized, single-arm trial that utilized data from 144 patients enrolled in the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) database at 26 centers in the United States and Canada. The primary composite end-point was success at 180 days defined as alive on the originally implanted device and free from disabling stroke (modified Rankin Scale score >3), transplanted or explanted for recovery. The key secondary end-point was mean length of initial hospital stay. RESULTS: The primary end-point was successfully achieved in 88.1% of patients and was significantly greater than the pre-defined performance goal of 77.5% set from historical sternotomy data (p = 0.0012). The key secondary end-point-mean length of initial hospital stay -was 18 days and was significantly shorter than the pre-defined performance goal of 26.1 days obtained from historical sternotomy data (p < 0.0001). The adverse event profile further demonstrated the safety of the thoracotomy approach. The overall patient survival was good, and bleeding requiring reoperation was significantly less frequent than that observed in previous studies using the sternotomy approach. CONCLUSIONS: This prospective clinical trial provides validation that implantation of the HVAD system via the thoracotomy approach used in the LATERAL study represents a safe and effective alternative to median sternotomy in selected patients intended for a bridge-to-transplant indication.


Assuntos
Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Implantação de Prótese/métodos , Esternotomia , Toracotomia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese , Toracotomia/métodos
18.
Artif Organs ; 32(10): 819-22, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18959671

RESUMO

We present a regimen for anticoagulation in the immediate postoperative period after left ventricular assist device (LVAD) implantation using low molecular weight heparin (LMWH) as an alternative to unfractionated heparin. Between May and September 2007, eight consecutive patients undergoing LVAD implantation for advanced heart failure received the LMWH nadroparin. Nadroparin was given twice daily to achieve anti-Factor Xa activity target peak levels of 0.4 +/- 0.1 U/mL. The antiplatelet therapy consisted of aspirin (100 mg/day) and dipyridamole (3 x 75 mg/day). One patient underwent heart transplantation, three patients died, and four patients continued to receive device support. The median duration of support was 78 days (range, 46 to 174). No major bleeding was observed; minor bleeding occurred in three patients. In two patients, pump thrombosis was suspected. There were two ischemic and no hemorrhagic strokes. The use of LMWH may provide a new anticoagulation treatment option in the immediate postoperative period after LVAD implantation.


Assuntos
Heparina de Baixo Peso Molecular/administração & dosagem , Idoso , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Aspirina/administração & dosagem , Dipiridamol/administração & dosagem , Insuficiência Cardíaca/cirurgia , Insuficiência Cardíaca/terapia , Coração Auxiliar , Heparina/química , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Pessoa de Meia-Idade , Nadroparina/administração & dosagem , Nadroparina/uso terapêutico , Avaliação de Resultados em Cuidados de Saúde , Período Pós-Operatório , Próteses e Implantes/efeitos adversos , Trombose/prevenção & controle
19.
Artigo em Inglês | MEDLINE | ID: mdl-30070779

RESUMO

Giant coronary artery aneurysms are rare, difficult to diagnose, and have variable clinical presentations and treatment options. We demonstrate a case of a patient presenting with acute onset chest pain and signs of cardiac tamponade who then underwent a computed tomography pulmonary embolus protocol and was found to have hemopericardium with accumulation of contrast adjacent to the aorta. She then underwent emergent sternotomy and was found to have a large hemorrhagic mass on the right ventricle, which upon further dissection was determined to be a giant right coronary artery aneurysm with a site of contained rupture. Given the acuity of the presentation and the circumstances in which the giant coronary aneurysm was identified, the decision was made to ligate and bypass the affected coronary artery.


Assuntos
Aneurisma Coronário/diagnóstico , Vasos Coronários/cirurgia , Embolia Pulmonar/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Aneurisma Coronário/complicações , Aneurisma Coronário/cirurgia , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/complicações , Embolia Pulmonar/diagnóstico , Tomografia Computadorizada por Raios X
20.
Interact Cardiovasc Thorac Surg ; 27(5): 787-789, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29800339

RESUMO

Giant coronary artery aneurysms are rare and have variable presentations, which range from an incidental finding to sudden death. We report a case of a female presenting with chest pain and signs of cardiac tamponade who underwent a computed tomography (CT) pulmonary embolus protocol and was found to have haemopericardium with accumulation of contrast adjacent to the aorta. She underwent emergent sternotomy and was found to have a ruptured giant right coronary artery aneurysm, which was ligated and bypassed. This report highlights the difficulty of diagnosing a ruptured giant coronary artery aneurysm via CT and provides valuable information on an atypical presentation.


Assuntos
Aneurisma Roto/complicações , Tamponamento Cardíaco/etiologia , Aneurisma Coronário/complicações , Vasos Coronários/diagnóstico por imagem , Aneurisma Roto/diagnóstico , Aneurisma Roto/cirurgia , Tamponamento Cardíaco/diagnóstico , Aneurisma Coronário/diagnóstico , Aneurisma Coronário/cirurgia , Vasos Coronários/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Pessoas Transgênero , Procedimentos Cirúrgicos Vasculares/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA