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2.
Transpl Infect Dis ; 20(6): e12979, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30120865

RESUMO

BACKGROUND: Tacrolimus is a cornerstone of immunosuppression after transplantation but is highly susceptible to changes from interacting variables and has a narrow therapeutic index. Clotrimazole troches are commonly used as a non-systemic antifungal to prevent oral candidiasis. Studies suggest that clotrimazole troches, though minimally absorbed systemically, may affect tacrolimus concentrations by inhibition of metabolic enzyme activity in the intestines. However, the magnitude of the impact of clotrimazole on tacrolimus dosing requirements to maintain goal levels is not well described. METHODS: To assess this, tacrolimus dose adjustments and trough concentrations were retrospectively examined in 95 heart transplant recipients before and after the discontinuation of clotrimazole. RESULTS: The median percent tacrolimus dose change was an increase of 66.7% (IQR 28.6%, 100%) after clotrimazole discontinuation, and the median trough concentration percent change from baseline to the first trough after clotrimazole discontinuation (in the absence of a dose change) was -42.5% (IQR -52.3%, -30.9%). Five cases of allograft rejection were observed. CONCLUSION: In conclusion, clotrimazole troches exert a meaningful interaction with tacrolimus that requires close monitoring and dose adjustment. The data from this single-center study provide novel information that could guide providers on the degree of tacrolimus dose adjustment needed when discontinuing clotrimazole prophylaxis after heart transplantation.


Assuntos
Antifúngicos/farmacologia , Candidíase Bucal/prevenção & controle , Clotrimazol/farmacologia , Transplante de Coração/efeitos adversos , Imunossupressores/administração & dosagem , Tacrolimo/administração & dosagem , Administração Oral , Candidíase Bucal/imunologia , Interações Medicamentosas , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Humanos , Terapia de Imunossupressão/efeitos adversos , Terapia de Imunossupressão/métodos , Imunossupressores/sangue , Imunossupressores/farmacologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tacrolimo/sangue , Tacrolimo/farmacologia , Resultado do Tratamento
4.
Heart Lung Circ ; 23(3): 224-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23954004

RESUMO

INTRODUCTION: Cardiac transplantation is an effective surgical therapy for end-stage heart failure. Patients (pts) may need to be bridged with a continuous flow left ventricular assist device (CF-LVAD) while on the transplant list as logistic factors like organ availability are unknown. Cardiac transplantation post-LVAD can be a surgically challenging procedure and outcome in these pts is perceived to be poorer based on experience with earlier generation pulsatile flow pumps. Data from a single institution comparing these pts with those undergoing direct transplantation in the present era of continuous flow device therapy are limited. AIM: Evaluate results of cardiac transplantation in pts bridged with a CF-LVAD (BTx) and compare outcomes with pts undergoing direct transplantation (Tx) in a single institution. RESULTS: From June 2007 till January 2012, 106 pts underwent cardiac transplantation. Among these, 37 (35%) pts (51±11 years; 85% male) were bridged with a CF-LVAD (BTx), while 70 (65%) comprised the Tx group (53±12 years; 72% males). The median duration of LVAD support was 227 (153,327) days. During the period of LVAD support, 10/37 (27%) pts were upgraded to status 1A and all were successfully transplanted. Median hospital stay in the BTx (14 days) was slightly longer than the Tx group (12 days) but not statistically significant (p=0.21). In-hospital mortality in the BTx (5%) and Tx (1%) were comparable (p=0.25). Estimated late survival in the BTx cohort was 94±7, 90±10 and 83±16% at the end of one, two and three years, respectively which was comparable to 97±4%, 93±6% and 89±9% for the Tx group (p=0.50). CONCLUSION: Cardiac transplantation after LVAD implant can be performed with excellent results. Patients can be supported on the left ventricular assist device even for periods close to a year with good outcome after cardiac transplantation.


Assuntos
Cardiomiopatias , Transplante de Coração/métodos , Coração Auxiliar , Adulto , Idoso , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Cardiomiopatias/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
5.
Circulation ; 125(5): 708-20, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22207715

RESUMO

BACKGROUND: We retrospectively analyzed the potential of sirolimus as a primary immunosuppressant in the long-term attenuation of cardiac allograft vasculopathy progression and the effects on cardiac-related morbidity and mortality. METHODS AND RESULTS: Forty-five cardiac transplant recipients were converted to sirolimus 1.2 years (0.2, 4.0) after transplantation with complete calcineurin inhibitor withdrawal. Fifty-eight control subjects 2.0 years (0.2, 6.5 years) from transplantation were maintained on calcineurin inhibitors. Age, sex, ejection fraction, and time from transplantation to baseline intravascular ultrasound study were not different (P>0.2 for all) between the groups; neither were secondary immunosuppressants and use of steroids. Three-dimensional intravascular ultrasound studies were performed at baseline and 3.1 years (1.3, 4.6 years) later. Plaque index progression (plaque volume/vessel volume) was attenuated in the sirolimus group (0.7±10.5% versus 9.3±10.8%; P=0.0003) owing to reduced plaque volume in patients converted to sirolimus early (<2 years) after transplantation (P=0.05) and improved positive vascular remodeling (P=0.01) in patients analyzed late (>2 years) after transplantation. Outcome analysis in 160 consecutive patients maintained on 1 therapy was performed regardless of performance of intravascular ultrasound examinations. Five-year survival was improved with sirolimus (97.4±1.8% versus 81.8±4.9%; P=0.006), as was freedom from cardiac-related events (93.6±3.2% versus 76.9±5.5%; P=0.002). CONCLUSIONS: Substituting calcineurin inhibitor with sirolimus as primary immunosuppressant attenuates long-term cardiac allograft vasculopathy progression and may improve long-term allograft survival owing to favorable coronary remodeling. Because of the lack of randomization and retrospective nature of our analysis, the differences in outcome should be interpreted cautiously, and prospective clinical trials are required.


Assuntos
Doença da Artéria Coronariana/prevenção & controle , Transplante de Coração/mortalidade , Imunossupressores/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Sirolimo/uso terapêutico , Doenças Vasculares/prevenção & controle , Adulto , Calcineurina/uso terapêutico , Angiografia Coronária , Doença da Artéria Coronariana/epidemiologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Homólogo , Resultado do Tratamento , Ultrassonografia de Intervenção , Doenças Vasculares/diagnóstico por imagem
6.
Pharmacogenet Genomics ; 23(12): 658-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24121523

RESUMO

OBJECTIVES: Azathioprine (AZA) is an important immunosuppressant drug used in heart transplantation (HTX). Consensus guidelines recommend that patients with thiopurine S-methyltransferase (TPMT) genetic variants be started on lower AZA dose because of higher active metabolite levels and risk of adverse events. However, in-vitro lymphocyte proliferation assays performed in participants with inactive TPMT alleles have suggested that AZA use may result in decreased immunosuppressant efficacy as compared with wild-type (WT) individuals. The objective of this study was therefore to determine the effect of TPMT genetic variation on AZA efficacy or prevention of rejection in HTX recipients treated with AZA. PARTICIPANTS AND METHODS: We genotyped 93 HTX recipients treated with AZA and measured erythrocyte TPMT enzyme activity. Acute rejection was monitored by routine endomyocardial biopsies. RESULTS: There were 83 WT and 10 heterozygote (HZ) HTX recipients. TPMT activity level was lower in HZ compared with WT (13.1±2.8 vs. 21±4.5 U/ml red blood cell, P<0.001). Despite similar AZA dose, HZ developed severe rejection earlier (P<0.001), and the total rejection score was higher (P=0.02) than WT. AZA was discontinued more frequently in HZ (P=0.01) because of rejection. The incidence of leukopenia was similar between the groups (40 vs. 43%, P=1.0). CONCLUSION: HTX recipients with TPMT genetic variant alleles who are treated with AZA develop acute rejection earlier, more frequently, and of greater severity. These patients, despite having lower TPMT enzymatic activity, should be monitored carefully for possible increased risk of acute rejection.


Assuntos
Azatioprina/administração & dosagem , Rejeição de Enxerto/genética , Transplante de Coração/efeitos adversos , Imunossupressores/administração & dosagem , Metiltransferases/genética , Adulto , Azatioprina/efeitos adversos , Feminino , Variação Genética , Rejeição de Enxerto/prevenção & controle , Heterozigoto , Humanos , Imunossupressores/efeitos adversos , Masculino , Metiltransferases/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
J Card Surg ; 28(2): 109-16, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23488578

RESUMO

BACKGROUND: Anti-platelet therapy is an important component of medical therapy post coronary artery bypass grafting (CABG). While aspirin administration is a Class I indication after CABG, the benefit of concomitant clopidogrel is a controversial issue. METHODS: We searched OVID Medline, Cochrane, Scopus, and EMBASE for randomized control trials and observational studies comparing aspirin ± placebo to aspirin + clopidogrel after CABG. RESULTS: Eleven articles (five randomized control trials and six observational studies) including 25,728 patients met inclusion criteria. Early saphenous vein graft occlusion was reduced with the use of dual anti-platelet therapy (risk ratio (RR) = 0.59, 95% CI 0.43-0.82, p = 0.02). In-hospital or 30-day mortality was lower with aspirin + clopidogrel (0.8%) compared to aspirin alone (1.9%) (p < 0.0001), while risk of angina or perioperative myocardial infarction was comparable (RR = 0.60, 95% CI 0.31-1.14, p = 0.12). Patients treated with aspirin + clopidogrel demonstrated a trend towards a higher incidence of major bleeding episodes as compared to patients treated with aspirin alone (RR = 1.17, 95% CI 1.00-1.37, p = 0.05). In a pooled analysis of studies involving off-pump CABG compared to aspirin alone, dual anti-platelet therapy reduced the risk of perioperative myocardial infarction and saphenous graft occlusion by 68% (47% to 71%) and 55% (2% to 79%) respectively. CONCLUSION: Dual anti-platelet therapy after CABG improved early saphenous vein graft patency, but may increase the risk of bleeding. The use of dual anti-platelet therapy appears to be most beneficial in patients undergoing off-pump CABG. Prospective randomized studies are necessary to determine whether this beneficial effect of dual therapy is also achieved in patients undergoing on pump CABG.


Assuntos
Aspirina/uso terapêutico , Ponte de Artéria Coronária , Oclusão de Enxerto Vascular/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Cuidados Pós-Operatórios/métodos , Ticlopidina/análogos & derivados , Angina Pectoris/etiologia , Angina Pectoris/prevenção & controle , Clopidogrel , Ponte de Artéria Coronária/mortalidade , Quimioterapia Combinada , Humanos , Modelos Estatísticos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/prevenção & controle , Hemorragia Pós-Operatória/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto , Ticlopidina/uso terapêutico , Resultado do Tratamento
8.
ASAIO J ; 69(10): 950-955, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37367716

RESUMO

The literature regarding Clostridioides difficile infection (CDI) in left ventricular assist devices (LVADs) patients is limited. Therefore, we aimed to characterize the clinical course, risk factors, management, and outcomes of LVAD patients who developed CDI. Adult patients who underwent LVAD placement during 2010-2022 and developed CDI were included. To determine risk factors and outcomes, we matched CDI patients with LVAD patients who did not develop CDI. Each CDI case was matched with up to two control subjects by age, sex, and time from LVAD implantation. Forty-seven of 393 LVAD patients (12.0%) developed CDI. The median time from LVAD implantation to CDI was 147 days (interquartile range 22.5-647.0). The most common CDI treatment was oral vancomycin (n = 26, 55.3%). Thirteen patients (27.7%) required treatment extension because of a lack of clinical response. Three patients (6.4%) developed recurrent CDI. When 42 cases were matched to 79 control subjects, antibiotic exposure within 90 days was significantly associated with CDI (adjusted odds ratio 5.77; 95% confidence interval, 1.87-17.74; p = 0.002). Moreover, CDI was associated with 1 year mortality (adjusted hazard ratio 2.62; 95% confidence interval, 1.18-5.82; p = 0.018). This infection occurs most often within the first year after LVAD implantation and was associated with 1 year mortality. Antibiotic exposure is an important risk for CDI.


Assuntos
Infecções por Clostridium , Coração Auxiliar , Adulto , Humanos , Coração Auxiliar/efeitos adversos , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Infecções por Clostridium/etiologia , Infecções por Clostridium/induzido quimicamente , Fatores de Risco
9.
Mayo Clin Proc ; 98(3): 372-385, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36868745

RESUMO

OBJECTIVE: To ascertain whether heart failure (HF) itself is a senescent phenomenon independent of age, and how this is reflected at a molecular level in the circulating progenitor cell niche, and at a substrate level using a novel electrocardiogram (ECG)-based artificial intelligence platform. PATIENTS AND METHODS: Between October 14, 2016, and October 29, 2020, CD34+ progenitor cells were analyzed by flow cytometry and isolated by magnetic-activated cell sorting from patients of similar age with New York Heart Association functional classes IV (n = 17) and I-II (n = 10) heart failure with reduced ejection fraction and healthy controls (n = 10). CD34+ cellular senescence was quantitated by human telomerase reverse transcriptase expression and telomerase expression by quantitative polymerase chain reaction, and senescence-associated secretory phenotype (SASP) protein expression assayed in plasma. An ECG-based artificial intelligence (AI) algorithm was used to determine cardiac age and difference from chronological age (AI ECG age gap). RESULTS: CD34+ counts and telomerase expression were significantly reduced and AI ECG age gap and SASP expression increased in all HF groups compared with healthy controls. Expression of SASP protein was closely associated with telomerase activity and severity of HF phenotype and inflammation. Telomerase activity was more closely associated with CD34+ cell counts and AI ECG age gap. CONCLUSION: We conclude from this pilot study that HF may promote a senescent phenotype independent of chronological age. We show for the first time that the AI ECG in HF shows a phenotype of cardiac aging beyond chronological age, and appears to be associated with cellular and molecular evidence of senescence.


Assuntos
Insuficiência Cardíaca , Telomerase , Humanos , Inteligência Artificial , Projetos Piloto , Eletrocardiografia , Biomarcadores
10.
Heliyon ; 7(8): e07779, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34458617

RESUMO

The localization and quantification of endothelial progenitor cells (EPCs) are controversial. Circulating CD34 + cells in blood have been identified as EPCs and as biomarkers of cardiovascular disease. We discuss in this paper the current data describing differential phenotype and behavior in vitro of CD34 positive cells from the circulation and adipose tissue (AT). We also describe in brief our own findings from CD34 + cells isolated from leukopheresis cones derived from healthy platelet donors and from patients undergoing bariatric surgery. We conclude that CD34 + cells in blood and in AT are different in antigenic profile and behavior in culture. The findings described assert that CD34 + cells detected in blood previously identified as biomarkers of cardiovascular disease are predominantly HPCs rather than EPCs, and that true CD34 + EPCs can be readily identified and extracted from AT, supportive of the current evidence which suggests EPCs are resident in the tissue vasculature.

11.
Case Rep Cardiol ; 2021: 6641108, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763259

RESUMO

We present an adolescent African American male admitted to the cardiac intensive care unit with cardiogenic shock and acute respiratory failure. Through an overview of his presentation, diagnostic workup, and treatment, we demonstrate the clinical utility of genetic testing in the evaluation of unexplained dilated cardiomyopathies.

12.
Cureus ; 13(8): e17180, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34548982

RESUMO

Obstructive left ventricular assist device (LVAD) lesions are uncommon but are being increasingly recognized, particularly with the increased use of advanced imaging modalities. While heart failure symptoms and LVAD power fluctuations have a broad differential, obstructive lesions in the LVAD circuit should be considered. We present a unique case of a patient supported on HeartWare HVAD (Medtronic Inc., Dublin, Ireland) therapy, who experienced postural dizziness with objective orthostatic hypotension and occasional ventricular tachycardia. With fluctuations in LVAD flow and power, a CT scan with three-dimensional reconstruction was obtained showing outflow graft kinking. The patient was brought to the cardiac catheterization laboratory for investigation and consideration of outflow graft intervention. However, intracardiac echocardiography revealed the presence of an inflow cannula obstruction with position changes and catheter interrogation involving the outflow cannula suggestive of a gradient across the kinked area as an unlikely cause for the presentation. This case highlights the importance of a thorough interrogation for obstructive lesions in the setting of heart failure symptoms, particularly postural symptoms, in a patient on LVAD therapy, even when not identified on routine echocardiography.

13.
Mayo Clin Proc ; 96(4): 887-900, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33814091

RESUMO

OBJECTIVE: To characterize the properties of the audible tones produced by current left ventricular assist device (LVAD) pumps approved for use, and to ascertain if changes in those may be present in the setting of pump thrombosis. PATIENTS AND METHODS: From August 31, 2016, to January 16, 2020, LVAD recipients consented to have surface recordings obtained using a high-fidelity digital stethoscope. Audio data were analyzed using digital recording and editing software to produce an acoustic spectrogram by Fast Fourier transformation. RESULTS: Recordings were obtained in 53 patient encounters (27 HeartMate II, 19 HeartWare and 7 HeartMate 3). In 12 patients (9 HeartMate II, 3 HeartWare) there was a clinical concern for pump thrombosis. In all patients and pump models, a fundamental frequency was noted, and the second and third harmonics were also clearly detectable. Where thrombosis occurred in the HeartMate II pump, the absolute (normal -46.9 [-57.5,-42.9] dB vs thrombosis -41.4 [-49.8,-26.8] dB; P=.08) and relative (normal 0.72 [0.62, 0.92] vs thrombosis 0.95 [0.86, 1.24]; P=.01) third harmonic frequencies were increased in amplitude. Where paired data were available, an increase in the absolute and relative third harmonic frequencies was observed in all patients. In the case of the HeartWare device, a consistent difference in harmonic amplitudes in the setting of thrombosis could not be identified. CONCLUSION: A consistent pattern of fundamental and harmonic frequencies is common to all LVADs currently approved for use. Alterations in the amplitude of higher order harmonics may signal the onset of pump thrombosis in axial flow LVADs.


Assuntos
Acústica , Circulação Sanguínea/fisiologia , Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Trombose/prevenção & controle , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
J Am Coll Cardiol ; 77(10): 1331-1340, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33706876

RESUMO

BACKGROUND: In patients undergoing heart transplantation, significant allosensitization limits access to organs, resulting in longer wait times and high waitlist mortality. Current desensitization strategies are limited in enabling successful transplantation. OBJECTIVES: The purpose of this study was to describe the cumulative experience of combined heart-liver transplantation using a novel heart-after-liver transplant (HALT) protocol resulting in profound immunologic protection. METHODS: Reported are the results of a clinical protocol that was instituted to transplant highly sensitized patients requiring combined heart and liver transplantation at a single institution. Patients were dual-organ listed with perceived elevated risk of rejection or markedly prolonged waitlist time due to high levels of allo-antibodies. Detailed immunological data and long-term patient and graft outcomes were obtained. RESULTS: A total of 7 patients (age 43 ± 7 years, 86% women) with high allosensitization (median calculated panel reactive antibody = 77%) underwent HALT. All had significant, unacceptable donor specific antibodies (DSA) (>4,000 mean fluorescence antibody). Prospective pre-operative flow cytometric T-cell crossmatch was positive in all, and B-cell crossmatch was positive in 5 of 7. After HALT, retrospective crossmatch (B- and T-cell) became negative in all. DSA fell dramatically; at last follow-up, all pre-formed or de novo DSA levels were insignificant at <2,000 mean fluorescence antibody. No patients experienced >1R rejection over a median follow-up of 48 months (interquartile range: 25 to 68 months). There was 1 death due to metastatic cancer and no significant graft dysfunction. CONCLUSIONS: A heart-after-liver transplantation protocol enables successful transplantation via near-elimination of DSA and is effective in preventing adverse immunological outcomes in highly sensitized patients listed for combined heart-liver transplantation.


Assuntos
Rejeição de Enxerto/prevenção & controle , Transplante de Coração , Transplante de Fígado , Imunologia de Transplantes , Adulto , Protocolos Clínicos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Heart Lung ; 49(5): 481-487, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32334843

RESUMO

Ventricular tachycardia (VT) is common in LVAD recipients, and although often well tolerated, may result in symptoms and ICD therapies, and therefore require further evaluation and treatment. However, preload deficiency may also contribute to the development of ventricular tachycardia after LVAD implantation by provoking inflow cannula related VT. In this report, three cases are described where ventricular tachycardia was evaluated by integrated assessment utilizing echo and the HeartWare HVAD console, and successfully treated by modification of LV loading conditions.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Taquicardia Ventricular , Arritmias Cardíacas , Coração Auxiliar/efeitos adversos , Humanos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologia
16.
Stroke ; 40(5): 1886-91, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19286583

RESUMO

BACKGROUND AND PURPOSE: Adipose tissue is an abundant source of endothelial cells as well as stem and progenitor cells which can develop an endothelial phenotype. It has been demonstrated that these cells have distinct angiogenic properties in vitro and in vivo. However, whether these cells have the capacity to directly improve large vessel form and function after vascular injury remains unknown. To define whether delivery of adipose-derived endothelial cells (ADECs) would improve healing of injured carotid arteries, a rabbit model of acute arterial injury was used. METHODS: Autologous rabbit ADECs were generated using defined culture conditions. To test the ability of ADECs to enhance carotid artery repair, cells were delivered intraarterially after acute balloon injury. Additional delivery studies were performed after functional selection of cells before delivery. RESULTS: After rabbit omental fat harvest and digestion, a proliferative, homogenous, and distinctly endothelial population of ADECs was identified. Direct delivery of autologous ADECs resulted in marked reendothelialization 48 hours after acute vascular injury as compared to saline controls (82.2+/-26.9% versus 4.2+/-3.0% P<0.001). Delivery of ADECs that were selected for their ability to take up acetylated LDL significantly improved vasoreactivity and decreased intimal formation after vascular injury. CONCLUSIONS: Taken together, these data suggest that ADECs represent an autologous source of proliferative endothelial cells, which demonstrate the capacity to rapidly improve reendothelialization, improve vascular reactivity, and decrease intimal formation in a carotid artery injury model.


Assuntos
Tecido Adiposo/transplante , Doenças das Artérias Carótidas/terapia , Células Endoteliais/transplante , Acetilação , Tecido Adiposo/citologia , Animais , Artérias Carótidas/patologia , Cateterismo , Células Cultivadas , LDL-Colesterol/metabolismo , Endotélio Vascular/crescimento & desenvolvimento , Citometria de Fluxo , Imuno-Histoquímica , Microscopia Confocal , Coelhos
17.
J Transl Med ; 7: 66, 2009 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-19640275

RESUMO

BACKGROUND: The development of cell-based therapeutics for humans requires preclinical testing in animal models. The use of autologous animal products fails to address the efficacy of similar products derived from humans. We used a novel immunodeficient rat carotid injury model in order to determine whether human cells could improve vascular remodelling following acute injury. METHODS: Human CD34+ cells were separated from peripheral buffy coats using automatic magnetic cell separation. Carotid arterial injury was performed in male Sprague-Dawley nude rats using a 2F Fogarty balloon catheter. Freshly harvested CD34+ cells or saline alone was administered locally for 20 minutes by endoluminal instillation. Structural and functional analysis of the arteries was performed 28 days later. RESULTS: Morphometric analysis demonstrated that human CD34+ cell delivery was associated with a significant reduction in intimal formation 4 weeks following balloon injury as compared with saline (I/M ratio 0.79 +/- 0.18, and 1.71 +/- 0.18 for CD34, and saline-treated vessels, respectively P < 0.05). Vasoreactivity studies showed that maximal relaxation of vessel rings from human CD34+ treated animals was significantly enhanced compared with saline-treated counterparts (74.1 +/- 10.2, and 36.8 +/- 12.1% relaxation for CD34+ cells and saline, respectively, P < 0.05) CONCLUSION: Delivery of human CD34+ cells limits neointima formation and improves arterial reactivity after vascular injury. These studies advance the concept of cell delivery to effect vascular remodeling toward a potential human cellular product.


Assuntos
Antígenos CD34/administração & dosagem , Antígenos CD34/imunologia , Lesões das Artérias Carótidas/terapia , Cateterismo/efeitos adversos , Leucócitos Mononucleares/fisiologia , Animais , Biomarcadores/sangue , Artérias Carótidas/patologia , Lesões das Artérias Carótidas/etiologia , Modelos Animais de Doenças , Endotélio Vascular/citologia , Endotélio Vascular/crescimento & desenvolvimento , Humanos , Separação Imunomagnética , Leucócitos Mononucleares/citologia , Masculino , Ratos , Ratos Nus , Ratos Sprague-Dawley , Fatores de Tempo , Túnica Íntima/lesões , Túnica Íntima/patologia , Vasodilatação/fisiologia
18.
Curr Treat Options Cardiovasc Med ; 21(11): 75, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31773322

RESUMO

PURPOSE OF REVIEW: Left ventricular assist device (LVAD) implantation is a well-known treatment option for patients with advanced heart failure refractory to medical therapy and is recognized both as bridge to transplant and a destination therapy. The risk of ventricular arrhythmias (VAs) is common after LVAD implantation. We review the pathophysiology and recent advances in the management of VA in LVAD patients. RECENT FINDINGS: VAs are most likely to occur in the early post-operative periods after LVAD implantation and a prior history of VA is the most important risk factor. Post-LVAD VAs are usually well tolerated with less morbidity and decreased risk of sudden cardiac death. However, risk of right heart failure in the setting of persistent VAs is being increasingly recognized. The mechanisms of post-LVAD VAs may vary depending on the time from LVAD implantation. Electrical remodeling may play an important role in the immediate post-implant phase. Preexisting myocardial scar and to a lesser extent mechanical irritation from the LVAD cannula are important in the later phases. Most LVAD patients have a previously placed implantable cardioverter-defibrillator (ICD). The benefit of implanting a new ICD in LVAD patients is unknown and should be individualized. For ICD programming, a conservative strategy with higher detection zones and prolonged time to detection is usually recommended aiming to minimize ICD shocks. More aggressive programming is appropriate if the VA results in hemodynamic instability. Antiarrhythmic drugs including amiodarone, mexiletine, and beta blockers are usually the first-line therapy for VAs. Catheter ablation has been shown to be safe and effective in LVAD recipients with recurrent VAs not responsive to antiarrhythmic drugs. LVAD-related VA is most frequently reentrant secondary to myocardial scar and usually well tolerated. Management options include antiarrhythmic drugs and catheter ablation.

19.
ASAIO J ; 65(5): 443-448, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29768282

RESUMO

Left ventricular assist device (LVAD) pump thrombosis occurs in up to 8.4% of patients within 3-months postimplantation. Thromboelastography (TEG) could be used to signal hypercoagulability at LVAD implantation to predict patients at high risk for thrombosis. We sought to evaluate whether TEG maximum amplitude (MA) hypercoagulability (MA ≥69 mm) at the time of LVAD implantation predicts pump thrombosis. A single center, retrospective, nested case-control study was conducted using patients from January 1, 2005, to March 31, 2015. Each pump thrombosis case was matched to two control subjects based on age ± 5 years, sex, and duration of follow-up. A multivariable logistic regression analysis was performed on the matched sets; the odds ratio with 95% confidence interval (CI) was calculated to estimate the relative risk. Thirty-seven age- and sex-matched case-control sets were included for a total of 111 study participants. TEG-MA hypercoagulability occurred in 10.8% of the case group versus 6.8% of controls. There was no association between TEG-MA hypercoagulability and device thrombosis (odds ratio 1.71, 95% confidence interval 0.42-7.05, p = 0.46). Utilization of baseline TEG-MA hypercoagulability to detect individuals at risk for LVAD thrombosis is a novel concept. This study found no significant association between TEG-MA and LVAD thrombosis.


Assuntos
Coração Auxiliar/efeitos adversos , Tromboelastografia/métodos , Trombofilia , Trombose , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco , Trombofilia/etiologia , Trombose/etiologia
20.
ESC Heart Fail ; 5(6): 1118-1129, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30019530

RESUMO

AIMS: Early studies from the 1990s have shown that statins improve survival and attenuate cardiac allograft vasculopathy (CAV). However, little contemporary data are available on the incremental benefit of statins with the current use of new-generation immunosuppressive agents and the use of coronary intravascular ultrasound for assessment of CAV. We sought to investigate the effect of early statin (ES) as compared with late statin (LS) initiation after heart transplantation (HT) on long-term CAV progression and clinical outcomes in a large contemporary HT cohort. METHODS AND RESULTS: We analysed a cohort of 409 adult HT recipients. CAV progression was assessed by serial coronary intravascular ultrasound volumetric measurements of the differences between baseline and last follow-up plaque volume (PV) and plaque index (PV/vessel volume ratio). CAV progression and clinical outcomes were compared between the ES (<2 years after HT) and the LS (>2 years after HT) groups. During a median follow-up of 8.2 years, ES resulted in significantly lower change (Δ) of plaque index (+3.8% ± 1.7% vs. +8.2% ± 3.6%; P = 0.0008) and PV (+0.8 ± 0.3 vs. +1.9 ± 1.2; P = 0.045) compared with LS group. In a Cox proportional hazards regression model and after adjustment for baseline characteristics, ES was associated with a 52% decreased risk of CAV-associated events (hazard ratio 0.48, 95% confidence interval: 0.27-0.91; P = 0.025) and a 42% decreased risk of the composite endpoint of all-cause mortality and CAV-associated events (hazard ratio 0.58, 95% confidence interval: 0.38-0.91; P = 0.019). CONCLUSIONS: Early initiation of statin therapy after HT results in attenuated CAV progression as well as in decreased CAV-related events and mortality.


Assuntos
Acil Coenzima A/antagonistas & inibidores , Vasos Coronários/diagnóstico por imagem , Rejeição de Enxerto/tratamento farmacológico , Transplante de Coração/efeitos adversos , Imunossupressores/administração & dosagem , Doenças Vasculares/tratamento farmacológico , Aloenxertos , Biópsia , Progressão da Doença , Esquema de Medicação , Feminino , Seguimentos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Tempo para o Tratamento , Ultrassonografia de Intervenção , Doenças Vasculares/diagnóstico , Doenças Vasculares/etiologia
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