Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Int J Cardiol ; 326: 131-138, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33091520

RESUMO

AIM: Heart failure following myocardial infarction (MI) is a potentially lethal problem with a staggering incidence. The CardiAMP Heart Failure trial represents the first attempt to personalize marrow-derived cell-based therapy to individuals with cell characteristics associated with beneficial responses in prior trials. Before the initiation of the randomized pivotal trial, an open-label "roll-in cohort" was completed to ensure the feasibility of the protocol's procedures. METHODS: Patients with chronic post-MI heart failure (NYHA class II-III) receiving stable, guideline-directed medical therapy with a left ventricular ejection fraction between 20 and 40% were eligible. Two weeks prior to treatment, a ~ 5 mL bone marrow aspiration was performed to examine "cell potency". On treatment day, a 60 mL bone marrow aspiration, bone marrow mononuclear cell (BM MNC) enrichment and transendocardial injection of 200 million BM MNC's was performed in a single, point of care encounter. Patients were then followed to assess clinical outcomes. RESULTS: The cell potency small volume bone marrow aspirate, the 60 mL bone marrow aspirate, and transendocardial injections were well tolerated in 10 patients enrolled. There were no serious adverse events related to bone marrow aspiration or cell delivery. Improvement in 6-min walk distance was observed at 6 months (+47.8 m, P = 0.01) and trended to improvement at 12 months (+46.4, P = 0.06). Similarly, trends to improved NYHA heart failure functional class, quality of life, left ventricular ejection fraction and recruitment of previously akinetic left ventricular wall segments were observed. CONCLUSION: All CardiAMP HF protocol procedures were feasible and well tolerated. Favorable functional, echo and quality of life trends suggest this approach may offer promise for patients with post MI heart failure. The randomized CardiAMP Heart Failure pivotal trial is underway to confirm the efficacy of this approach. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02438306.


Assuntos
Insuficiência Cardíaca , Isquemia Miocárdica , Medula Óssea , Transplante de Medula Óssea , Terapia Baseada em Transplante de Células e Tecidos , Estudos de Viabilidade , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Qualidade de Vida , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
2.
Am Heart J ; 201: 141-148, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29803986

RESUMO

BACKGROUND: Heart failure following myocardial infarction is a common, disabling, and deadly condition. Direct injection of autologous bone marrow mononuclear cells into the myocardium may result in improved functional recovery, relieve symptoms, and improve other cardiovascular outcomes. METHODS: CardiAMP-HF is a randomized, double-blind, sham-controlled, pivotal trial designed to investigate the safety and efficacy of autologous bone marrow mononuclear cells treatment for patients with medically refractory and symptomatic ischemic cardiomyopathy. The primary end point is change in 6-minute walk distance adjusted for major adverse cardiovascular events at 12 months following treatment. Particularly novel aspects of this trial include a cell potency assay to screen subjects who have bone marrow cell characteristics that suggest a favorable response to treatment, a point-of-care treatment method, a high target dose of 200 million cells, and an efficient transcatheter intramyocardial delivery method that is associated with high cell retention. CONCLUSIONS: This novel approach may lead to a new treatment for those with ischemic heart disease suffering from medically refractory heart failure.


Assuntos
Transplante de Medula Óssea/métodos , Insuficiência Cardíaca/terapia , Monócitos/transplante , Infarto do Miocárdio/complicações , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Método Duplo-Cego , Feminino , Seguimentos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
3.
Int Heart J ; 58(3): 435-440, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28539564

RESUMO

Cardiac regeneration strategies using stem cells have shown variable and inconsistent results with respect to patient cardiac function and clinical outcomes. There has been increasing consensus that improving the efficiency of delivery may improve results. The Helix transendocardial delivery system (BioCardia Inc.) has been developed to enable percutaneous transendocardial biotherapeutic delivery. Therefore, we evaluated cell retention using this unique system compared with direct transepicardial injection and intracoronary infusion in an animal model.Twelve healthy swine were used in this study. 18Fluorodeoxyglucose (FDG)-labeled bone marrow mononuclear cells were delivered via percutaneous transendocardial route using the Helix system (TE group, n = 5), via direct transepicardial injection using a straight 27-gauge needle in an open chest procedure (TP group, n = 4), or via percutaneous intracoronary (IC) infusion (IC group, n = 3). One hour after cell delivery, the distribution of injected cells within the myocardium was assessed by PET-CT. Regions of interest were defined and their signals were compared in each group. Retention rates were calculated as a percentage of the comparing signal.The distribution of injected cells in the myocardium was higher in the TE group (17.9%) than in the TP group (6.0%, versus TE, P < 0.001) and the IC group (1.0%, versus TE, P < 0.001). Consistent with previous reports, there were signal distributions in the lungs, liver, and kidneys in qualitative whole body PET assessment.TE cell delivery using a helical infusion catheter is more efficient in cell retention than either TP delivery or IC delivery using PET-CT analysis.


Assuntos
Cateteres Cardíacos , Terapia Baseada em Transplante de Células e Tecidos/instrumentação , Sistemas de Liberação de Medicamentos/instrumentação , Isquemia Miocárdica/terapia , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Animais , Modelos Animais de Doenças , Endocárdio , Desenho de Equipamento , Feminino , Isquemia Miocárdica/diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Suínos
4.
Circ Res ; 114(8): 1292-301, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24449819

RESUMO

RATIONALE: Transendocardial stem cell injection (TESI) with mesenchymal stem cells improves remodeling in chronic ischemic cardiomyopathy, but the effect of the injection site remains unknown. OBJECTIVE: To address whether TESI exerts its effects at the site of injection only or also in remote areas, we hypothesized that segmental myocardial scar and segmental ejection fraction improve to a greater extent in injected than in noninjected segments. METHODS AND RESULTS: Biplane ventriculographic and endocardial tracings were recorded. TESI was guided to 10 sites in infarct-border zones. Sites were mapped according to the 17-myocardial segment model. As a result, 510 segments were analyzed in 30 patients before and 13 months after TESI. Segmental early enhancement defect (a measure of scar size) was reduced by TESI in both injected (-43.7 ± 4.4%; n=95; P<0.01) and noninjected segments (-25.1 ± 7.8%; n=148; P<0.001; between-group comparison P<0.05). Conversely, segmental ejection fraction (a measure of contractile performance) improved in injected scar segments (19.9 ± 3.3-26.3 ± 3.5%; P=0.003) but not in noninjected scar segments (21.3 ± 2.6-23.5 ± 3.2%; P=0.20; between-group comparison P<0.05). Furthermore, segmental ejection fraction in injected scar segments improved to a greater degree in patients with baseline segmental ejection fraction <20% (12.1 ± 1.2-19.9 ± 2.7%; n=18; P=0.003), versus <20% (31.7 ± 3.4-35.5 ± 3.3%; n=12; P=0.33, between-group comparison P<0.0001). CONCLUSIONS: These findings illustrate a dichotomy in regional responses to TESI. Although scar size reduction was evident in all scar segments, scar size reduction and ventricular functional responses preferentially occurred at the sites of TESI versus non-TESI sites. Furthermore, improvement was greatest when segmental left ventricular dysfunction was severe.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Cicatriz/patologia , Cicatriz/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Idoso , Cicatriz/diagnóstico por imagem , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Desenvolvimento Muscular/fisiologia , Infarto do Miocárdio/diagnóstico por imagem , Volume Sistólico/fisiologia , Tomografia Computadorizada Espiral , Resultado do Tratamento , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia
5.
JAMA ; 311(1): 62-73, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24247587

RESUMO

IMPORTANCE: Whether culture-expanded mesenchymal stem cells or whole bone marrow mononuclear cells are safe and effective in chronic ischemic cardiomyopathy is controversial. OBJECTIVE: To demonstrate the safety of transendocardial stem cell injection with autologous mesenchymal stem cells (MSCs) and bone marrow mononuclear cells (BMCs) in patients with ischemic cardiomyopathy. DESIGN, SETTING, AND PATIENTS: A phase 1 and 2 randomized, blinded, placebo-controlled study involving 65 patients with ischemic cardiomyopathy and left ventricular (LV) ejection fraction less than 50% (September 1, 2009-July 12, 2013). The study compared injection of MSCs (n=19) with placebo (n = 11) and BMCs (n = 19) with placebo (n = 10), with 1 year of follow-up. INTERVENTIONS: Injections in 10 LV sites with an infusion catheter. MAIN OUTCOMES AND MEASURES: Treatment-emergent 30-day serious adverse event rate defined as a composite of death, myocardial infarction, stroke, hospitalization for worsening heart failure, perforation, tamponade, or sustained ventricular arrhythmias. RESULTS: No patient had a treatment-emergent serious adverse events at day 30. The 1-year incidence of serious adverse events was 31.6% (95% CI, 12.6% to 56.6%) for MSCs, 31.6% (95% CI, 12.6%-56.6%) for BMCs, and 38.1% (95% CI, 18.1%-61.6%) for placebo. Over 1 year, the Minnesota Living With Heart Failure score improved with MSCs (-6.3; 95% CI, -15.0 to 2.4; repeated measures of variance, P=.02) and with BMCs (-8.2; 95% CI, -17.4 to 0.97; P=.005) but not with placebo (0.4; 95% CI, -9.45 to 10.25; P=.38). The 6-minute walk distance increased with MSCs only (repeated measures model, P = .03). Infarct size as a percentage of LV mass was reduced by MSCs (-18.9%; 95% CI, -30.4 to -7.4; within-group, P = .004) but not by BMCs (-7.0%; 95% CI, -15.7% to 1.7%; within-group, P = .11) or placebo (-5.2%; 95% CI, -16.8% to 6.5%; within-group, P = .36). Regional myocardial function as peak Eulerian circumferential strain at the site of injection improved with MSCs (-4.9; 95% CI, -13.3 to 3.5; within-group repeated measures, P = .03) but not BMCs (-2.1; 95% CI, -5.5 to 1.3; P = .21) or placebo (-0.03; 95% CI, -1.9 to 1.9; P = .14). Left ventricular chamber volume and ejection fraction did not change. CONCLUSIONS AND RELEVANCE: Transendocardial stem cell injection with MSCs or BMCs appeared to be safe for patients with chronic ischemic cardiomyopathy and LV dysfunction. Although the sample size and multiple comparisons preclude a definitive statement about safety and clinical effect, these results provide the basis for larger studies to provide definitive evidence about safety and to assess efficacy of this new therapeutic approach. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00768066.


Assuntos
Transplante de Medula Óssea/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Isquemia Miocárdica/terapia , Idoso , Transplante de Medula Óssea/efeitos adversos , Cardiomiopatias , Progressão da Doença , Método Duplo-Cego , Feminino , Hospitalização , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Infarto do Miocárdio , Acidente Vascular Cerebral , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento , Disfunção Ventricular Esquerda/terapia
6.
JAMA ; 308(22): 2369-79, 2012 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-23117550

RESUMO

CONTEXT: Mesenchymal stem cells (MSCs) are under evaluation as a therapy for ischemic cardiomyopathy (ICM). Both autologous and allogeneic MSC therapies are possible; however, their safety and efficacy have not been compared. OBJECTIVE: To test whether allogeneic MSCs are as safe and effective as autologous MSCs in patients with left ventricular (LV) dysfunction due to ICM. DESIGN, SETTING, AND PATIENTS: A phase 1/2 randomized comparison (POSEIDON study) in a US tertiary-care referral hospital of allogeneic and autologous MSCs in 30 patients with LV dysfunction due to ICM between April 2, 2010, and September 14, 2011, with 13-month follow-up. INTERVENTION: Twenty million, 100 million, or 200 million cells (5 patients in each cell type per dose level) were delivered by transendocardial stem cell injection into 10 LV sites. MAIN OUTCOME MEASURES: Thirty-day postcatheterization incidence of predefined treatment-emergent serious adverse events (SAEs). Efficacy assessments included 6-minute walk test, exercise peak VO2, Minnesota Living with Heart Failure Questionnaire (MLHFQ), New York Heart Association class, LV volumes, ejection fraction (EF), early enhancement defect (EED; infarct size), and sphericity index. RESULTS: Within 30 days, 1 patient in each group (treatment-emergent SAE rate, 6.7%) was hospitalized for heart failure, less than the prespecified stopping event rate of 25%. The 1-year incidence of SAEs was 33.3% (n = 5) in the allogeneic group and 53.3% (n = 8) in the autologous group (P = .46). At 1 year, there were no ventricular arrhythmia SAEs observed among allogeneic recipients compared with 4 patients (26.7%) in the autologous group (P = .10). Relative to baseline, autologous but not allogeneic MSC therapy was associated with an improvement in the 6-minute walk test and the MLHFQ score, but neither improved exercise VO2 max. Allogeneic and autologous MSCs reduced mean EED by −33.21% (95% CI, −43.61% to −22.81%; P < .001) and sphericity index but did not increase EF. Allogeneic MSCs reduced LV end-diastolic volumes. Low-dose concentration MSCs (20 million cells) produced greatest reductions in LV volumes and increased EF. Allogeneic MSCs did not stimulate significant donor-specific alloimmune reactions. CONCLUSIONS: In this early-stage study of patients with ICM, transendocardial injection of allogeneic and autologous MSCs without a placebo control were both associated with low rates of treatment-emergent SAEs, including immunologic reactions. In aggregate, MSC injection favorably affected patient functional capacity, quality of life, and ventricular remodeling. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01087996.


Assuntos
Transplante de Medula Óssea/métodos , Cardiomiopatias/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Isquemia Miocárdica/terapia , Idoso , Feminino , Antígenos HLA/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Transplante Autólogo , Transplante Homólogo , Resultado do Tratamento , Disfunção Ventricular Esquerda/terapia , Remodelação Ventricular
7.
EuroIntervention ; 7(7): 805-12, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22082576

RESUMO

AIMS: To assess the hypothesis that fluoroscopically-guided helical needle transendocardial delivery of autologous bone marrow (ABM) mononuclear cells (MNCs) in chronic post myocardial infarction patients is safe and improves ejection fraction (EF). METHODS AND RESULTS: Twenty ischaemic heart failure patients with an EF ≤40% were enrolled. ABMMNCs were prepared, counted for CD34+ and CD133+ content, and delivered percutaneously to the heart at 5 to 10 peri-infarct sites. Two-dimensional (2D) transthoracic echocardiography, EF measurements, Holter, and exercise tolerance time (ETT) were performed at baseline, one week (wk), and 6, 12, and 24 months (mo). 96±29 million ABMMNCs were injected into 8.5±2.6 peri-infarct sites over 42±17 minutes (n=20). There were no adverse events associated with the catheter-based cell transplantation procedure or significant increases in ventricular events on Holter. EF improved over baseline from 34.9±4.3% to 41.9±5.1% at 12 mo to 42.2±7.1% (p=0.00005) at 24 mo. ETT improvements were statistically significant from 246±113 sec to 373±183 sec at 12 mo and 371±181 sec at 24 mo (p=0.006). CONCLUSIONS: ABMMNCs delivered with the helical needle transendocardial catheter was safe in this uncontrolled open label study. Increased EF and ETT support the safety of the procedure and technologies involved and warrant additional investigation.


Assuntos
Transplante de Medula Óssea , Insuficiência Cardíaca/cirurgia , Infarto do Miocárdio/cirurgia , Idoso , Argentina , Transplante de Medula Óssea/efeitos adversos , Transplante de Medula Óssea/instrumentação , Catéteres , Ecocardiografia , Eletrocardiografia Ambulatorial , Desenho de Equipamento , Teste de Esforço , Tolerância ao Exercício , Feminino , Fluoroscopia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Agulhas , Radiografia Intervencionista , Recuperação de Função Fisiológica , Volume Sistólico , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento , Função Ventricular Esquerda
8.
Circ Res ; 108(7): 792-6, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21415390

RESUMO

RATIONALE: Transcatheter, intramyocardial injections of bone marrow-derived cell therapy produces reverse remodeling in large animal models of ischemic cardiomyopathy. OBJECTIVE: We used cardiac MRI (CMR) in patients with left ventricular (LV) dysfunction related to remote myocardial infarction (MI) to test the hypothesis that bone marrow progenitor cell injection causes functional recovery of scarred myocardium and reverse remodeling. METHODS AND RESULTS: Eight patients (aged 57.2±13.3 years) received transendocardial, intramyocardial injection of autologous bone marrow progenitor cells (mononuclear or mesenchymal stem cells) in LV scar and border zone. All patients tolerated the procedure with no serious adverse events. CMR at 1 year demonstrated a decrease in end diastolic volume (208.7±20.4 versus 167.4±7.32 mL; P=0.03), a trend toward decreased end systolic volume (142.4±16.5 versus 107.6±7.4 mL; P=0.06), decreased infarct size (P<0.05), and improved regional LV function by peak Eulerian circumferential strain in the treated infarct zone (-8.1±1.0 versus -11.4±1.3; P=0.04). Improvements in regional function were evident at 3 months, whereas the changes in chamber dimensions were not significant until 6 months. Improved regional function in the infarct zone strongly correlated with reduction of end diastolic volume (r(2)=0.69, P=0.04) and end systolic volume (r(2)=0.83, P=0.01). CONCLUSIONS: These data suggest that transcatheter, intramyocardial injections of autologous bone marrow progenitor cells improve regional contractility of a chronic myocardial scar, and these changes predict subsequent reverse remodeling. The findings support the potential clinical benefits of this new treatment strategy and ongoing randomized clinical trials.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Recuperação de Função Fisiológica/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/cirurgia , Remodelação Ventricular/fisiologia , Adulto , Idoso , Humanos , Injeções , Imageamento por Ressonância Magnética , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Infarto do Miocárdio/complicações , Projetos Piloto , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia
9.
Am Heart J ; 161(3): 487-93, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21392602

RESUMO

Although there is tremendous interest in stem cell (SC)-based therapies for cardiomyopathy caused by chronic myocardial infarction, many unanswered questions regarding the best approach remain. The TAC-HFT study is a phase I/II randomized, double-blind, placebo-controlled trial designed to address several of these questions, including the optimal cell type, delivery technique, and population. This trial compares autologous mesenchymal SCs (MSCs) and whole bone marrow mononuclear cells (BMCs). In addition, the study will use a novel helical catheter to deliver cells transendocardially. Although most trials have used intracoronary delivery, the optimal method is unknown and data suggest that the transendocardial approach may have important advantages. Several trials support the benefit of SCs in patients with chronic ischemic cardiomyopathy (ICMP), although the sample sizes have been small and the number of trials sparse. After a pilot phase of 8 patients, 60 patients with ICMP (left ventricular ejection fraction 15%-50%) will be randomized to group A (30 patients further randomized to receive MSC injection or placebo in a 2:1 fashion) or group B (30 patients further randomized to BMCs or placebo in a 2:1 fashion). All patients will undergo bone marrow aspiration and transendocardial injection of SCs or placebo. The primary and secondary objectives are, respectively, to demonstrate the safety and efficacy (determined primarily by cardiac magnetic resonance imaging) of BMCs and MSCs administered transendocardially in patients with ICMP.


Assuntos
Transplante de Medula Óssea/métodos , Insuficiência Cardíaca/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Disfunção Ventricular Esquerda/terapia , Método Duplo-Cego , Insuficiência Cardíaca/etiologia , Humanos , Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio/complicações , Coleta de Tecidos e Órgãos , Transplante Autólogo
10.
Am Heart J ; 154(1): 79.e1-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17584556

RESUMO

BACKGROUND: Cell therapy has shown benefit in preclinical and clinical studies, although debate continues on the mechanism of action and the most appropriate methods for performing such therapies. We assessed the hypothesis that helical needle transendocardial (TE) delivery of autologous bone marrow (ABM) mononuclear cells around regions of hypo- or akinesia in patients after chronic myocardial infarction (MI) would be safe and possibly improve ejection fraction (EF). METHODS AND RESULTS: Ten stable post-MI patients with an EF <40% were enrolled. Autologous bone marrow cells were aspirated from the iliac crest and delivered percutaneously with a TE helical needle catheter. A total of 86 x 10(6) cells were injected into 7.1 +/- 3.1 sites around the infarct to target the peri-infarct zones. Two-dimensional echocardiographic left ventricle EF measurements, 24-hour Holter, and exercise tolerance testing were performed at baseline, day of procedure, 1 and 12 weeks, and 6 and 12 months. There were no adverse events associated with the catheter-based cell transplantation procedure. At 6 and 12 months, all patients showed an improvement in left ventricle EF over baseline (35.2 +/- 4.6 to 40.8 +/- 4.5, P = .003 at 6 months; 35.2 +/- 4.6 to 42.3 +/- 5.1, P = .0001 at 12 months). CONCLUSIONS: Autologous bone marrow cells delivered with the helical needle TE catheter was safe in this small uncontrolled study in patients with chronic MI. Increased EF and other positive data trends support continued development of this therapeutic strategy in larger controlled trials.


Assuntos
Transplante de Medula Óssea/instrumentação , Transplante de Medula Óssea/métodos , Infarto do Miocárdio/terapia , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiologia , Transplante de Medula Óssea/efeitos adversos , Cateterismo , Doença Crônica , Teste de Esforço , Tolerância ao Exercício , Feminino , Seguimentos , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Projetos Piloto , Transplante Autólogo/instrumentação , Transplante Autólogo/métodos
11.
Lymphat Res Biol ; 1(1): 47-53; discussion 54, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15624321

RESUMO

BACKGROUND: Local intramyocardial delivery (IMD) is under active clinical investigation for cell therapies to treat congestive heart failure, and gene therapies to induce revascularization of ischemic myocardium in coronary artery disease. Locally delivered agents can migrate away from the site of delivery through pathways that include lymphatics. Postdelivery redistribution can be observed using fluorescent tracers of different physical geometries. This approach provides a means to characterize these pathways and to delineate their importance in local cardiovascular drug delivery. METHODS AND RESULTS: The left ventricular wall of rats (N = 83) received injections of fluorescent microspheres with mean diameters ranging from 20 nm to 15,000 nm. Fluorescent microscopy was used to observe and image the patterns of migration from the epicardial surface. The animals were sacrificed after delivery. The microspheres with diameters smaller than 200 nm were widely distributed within the lymphatic network on the epicardial surface of the rat heart and through the ventricular wall at the injection site. Cardiac lymph nodes were identified with 20 nm and 100 nm deliveries, but could not be identified in any deliveries 200 nm or larger. The 15000 nm microspheres did not migrate. CONCLUSIONS: Tortuous lymphatic pathways are apparent in the images of fluorescent sphere migration from the intramyocardial site of delivery. These images suggest a lymphatic role in the formation of native collaterals that may implicate potential advantages to IMD in therapeutic angiogenesis. Distribution postdelivery also suggests that IMD may provide a means to administer hydrophilic agents to the periadventitial zone of the arterial wall to limit restenosis. The lack of redistribution of the 15,000 nm microspheres supports the potential for cell therapies to remain localized over an extended time frame.


Assuntos
Sistemas de Liberação de Medicamentos , Linfonodos/fisiologia , Vasos Linfáticos/fisiologia , Miocárdio/patologia , Animais , Sistema Cardiovascular/efeitos dos fármacos , Corantes Fluorescentes/farmacologia , Coração/fisiologia , Ventrículos do Coração/patologia , Humanos , Microscopia de Fluorescência , Microesferas , Modelos Anatômicos , Modelos Biológicos , Neovascularização Patológica , Pericárdio/patologia , Ratos , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...