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1.
Heart Fail Rev ; 27(1): 147-161, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32564330

RESUMO

There is ongoing controversy regarding the association between loop diuretics (LD), especially in high doses, and adverse clinical outcomes in outpatients with heart failure (HF). We performed a systematic review of the evidence for LD in outpatients with HF. We searched MEDLINE, EMBASE, and Cochrane Clinical Trial Collection to identify controlled studies, evaluating the association between LD and morbidity and mortality in patients with HF. The primary endpoint was all-cause mortality and secondary endpoint HF hospitalizations. Quantitative analysis was performed by generating forest plots and pooling adjusted risk estimates across studies using random effects models. Between-study heterogeneity was assessed through Q and I2 statistics. Twenty-four studies with a total of 96,959 patients were included. No randomized studies were identified. Use of LD was associated with increased all-cause mortality compared with non-use (pooled adjusted risk estimates, 1.18; P = 0.001) and increased HF hospitalization rates (pooled adjusted risk estimates, 1.81; P < 0.001). These associations remained significant after excluding studies that included HF patients at discharge from hospital (pooled adjusted risk estimates, 1.31 and 1.89, respectively; P < 0.001 for both). High-dose LD (median dose 80 mg) were also associated with increased all-cause mortality (pooled adjusted risk estimates, 1.99; P < 0.001) compared with low-dose LD. Again, this association remained significant after excluding studies that included HF patients at discharge from hospital (pooled adjusted risk estimates, 1.33; P < 0.001). Existing evidence indicates that LD, especially in high doses, are associated with increased all-cause mortality and HF hospitalization rates. For this reason, prospective, randomized studies are warranted to clarify whether these associations indicate causality or are merely an epiphenomenon due to disease severity. Systematic review registration: PROSPERO database registration number CRD42020153239. Date of registration: 28 April 2020.


Assuntos
Insuficiência Cardíaca , Inibidores de Simportadores de Cloreto de Sódio e Potássio , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Hospitalização , Humanos , Pacientes Ambulatoriais , Estudos Prospectivos
2.
J Cardiovasc Pharmacol Ther ; 26(1): 88-99, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32677460

RESUMO

BACKGROUND: Allogeneic cardiosphere-derived cells (CDCs) exert cardioprotective effects when administered intracoronarily after reperfusion in animal models of acute myocardial infarction (AMI). The "no-reflow" phenomenon develops rapidly post-reperfusion and may undermine the efficacy of cell therapy, due to poor cell delivery in areas of microvascular obstruction (MVO). We hypothesized that CDC-induced cardioprotection would be enhanced by cell administration prior to reperfusion, when microvasculature is still relatively intact, to facilitate widespread cell delivery within the ischemic area. METHODS AND RESULTS: We studied 81 farm pigs; 55 completed the specified protocols. A dose-optimization study in infarcted pigs demonstrated that the doses of 5 million and 10 million CDCs are the maximum safe doses that can be administered intracoronarily at 5 minutes prior to and at 5 minutes post-reperfusion, respectively, without aggravating MVO. Quantification of acute cell retention by polymerase chain reaction demonstrated that cell delivery prior to reperfusion resulted in higher cardiac cell retention compared to delivery post-reperfusion. We then performed a randomized, placebo-controlled study to assess the long-term efficacy of intracoronary infusion of 5 million allogeneic CDCs, delivered at 5 minutes prior to reperfusion, in a porcine model of AMI. The CDC therapy resulted in decreased scar size, improved regional systolic function, and attenuation of adverse cardiac remodeling (manifested as preserved global systolic function, preserved end-systolic volume, and decreased interstitial fibrosis) compared to placebo at 30 days post-MI. CONCLUSIONS: Dose-optimized intracoronary infusion of allogeneic CDCs prior to reperfusion in a porcine model of AMI is feasible, safe and confers long-term benefits.


Assuntos
Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Miocárdio , Miócitos Cardíacos , Função Ventricular Esquerda , Remodelação Ventricular , Animais , Masculino , Células Cultivadas , Modelos Animais de Doenças , Fibrose , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/cirurgia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/cirurgia , Miocárdio/patologia , Miócitos Cardíacos/transplante , Sus scrofa , Transplante Homólogo
3.
Eur Heart J ; 41(36): 3451-3458, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32749459

RESUMO

AIMS: Cardiosphere-derived cells (CDCs) are cardiac progenitor cells that exhibit disease-modifying bioactivity in various models of cardiomyopathy and in previous clinical studies of acute myocardial infarction (MI), dilated cardiomyopathy, and Duchenne muscular dystrophy. The aim of the study was to assess the safety and efficacy of intracoronary administration of allogeneic CDCs in the multicentre, randomized, double-blinded, placebo-controlled, intracoronary ALLogeneic heart STem cells to Achieve myocardial Regeneration (ALLSTAR) trial. METHODS AND RESULTS: We enrolled patients 4 weeks to 12 months after MI, with left ventricular ejection fraction (LVEF) ≤45% and LV scar size ≥15% of LV mass by magnetic resonance imaging (MRI). A pre-specified interim analysis was performed when 6-month MRI data were available. The trial was subsequently stopped due to the low probability of detecting a significant treatment effect of CDCs based on the primary endpoint. Patients were randomly allocated in a 2:1 ratio to receive CDCs or placebo in the infarct-related artery by stop-flow technique. The primary safety endpoint was the occurrence, during 1-month post-intracoronary infusion, of acute myocarditis attributable to allogeneic CDCs, ventricular tachycardia- or ventricular fibrillation-related death, sudden unexpected death, or a major adverse cardiac event (death or hospitalization for heart failure or non-fatal MI or need for left ventricular assist device or heart transplant). The primary efficacy endpoint was the relative percentage change in infarct size at 12 months post-infusion as assessed by contrast-enhanced cardiac MRI. We randomly allocated 142 eligible patients of whom 134 were treated (90 to the CDC group and 44 to the placebo group). The mean baseline LVEF was 40% and the mean scar size was 22% of LV mass. No primary safety endpoint events occurred. There was no difference in the percentage change from baseline in scar size (P = 0.51) between CDCs and placebo groups at 6 months. Compared with placebo, there were significant reductions in LV end-diastolic volume (P = 0.02), LV end-systolic volume (P = 0.02), and N-terminal pro b-type natriuretic peptide (NT-proBNP) (P = 0.02) at 6 months in CDC-treated patients. CONCLUSION: Intracoronary infusion of allogeneic CDCs in patients with post-MI LV dysfunction was safe but did not reduce scar size relative to placebo at 6 months. Nevertheless, the reductions in LV volumes and NT-proBNP reveal disease-modifying bioactivity of CDCs. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01458405.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Função Ventricular Esquerda , Método Duplo-Cego , Coração , Humanos , Volume Sistólico , Resultado do Tratamento
4.
J Hum Hypertens ; 34(5): 339-345, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31937855

RESUMO

Hypertension (HTN) and sudden cardiac death (SCD) constitute major public health problems accounting for millions of deaths each year worldwide. Both HTN and HTN-induced left ventricular hypertrophy (LVH) have been shown to be independent risk factors for SCD. However, the association between antihypertensive pharmacotherapy and risk of SCD has been under-investigated. Given that antihypertensive pharmacotherapy effectively reduces overall cardiovascular mortality, it would be expected to protect patients from SCD. Nevertheless, available data demonstrate that antihypertensive medications (primarily thiazide diuretics), while effective in reducing the incidence of myocardial infarction, do not confer protection from SCD. The purpose of this review was to present the relationship between HTN, LVH, and SCD and to describe the potential association between antihypertensive pharmacotherapy and risk of SCD.


Assuntos
Hipertensão , Infarto do Miocárdio , Anti-Hipertensivos/uso terapêutico , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Fatores de Risco
5.
EuroIntervention ; 16(4): e293-e300, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31763984

RESUMO

AIMS: The DYNAMIC trial assessed the safety and explored the efficacy of multivessel intracoronary infusion of allogeneic cardiosphere-derived cells (CDCs) in patients with heart failure and reduced ejection fraction (HFrEF). Here we report the results of the DYNAMIC trial. METHODS AND RESULTS: We enrolled 14 patients with EF ≤35% and NYHA Class III-IV despite maximal medical and device-based therapy in this single-centre, open-label trial. Intracoronary catheterisation delivered four escalating doses (totalling 37.5-75 million cells) by sequential non-occlusive technique to all three major coronary arteries. The primary safety endpoint was a composite of post-infusion TIMI flow, ventricular tachycardia/fibrillation, sudden death, major adverse cardiac events or acute myocarditis within 72 hours. Twelve patients were male and EF averaged 23.0% (±4.5%). No primary safety endpoints were observed. Two patients died of HFrEF progression nine and 12 months following infusion. Compared to baseline, there was an improvement in EF (26.8% vs 22.9%, p=0.023) and left ventricular end-systolic volume (139.5 vs 177.8 cm3, p=0.03) at six months. Quality of life (QoL) scores and NYHA class (p=0.006) improved at six months. At 12 months, the improvement in EF and QoL remained significant. CONCLUSIONS: Global intracoronary infusion of allogeneic CDCs is safe and feasible. The efficacy of allogeneic CDCs in HFrEF needs to be tested in larger randomised trials.


Assuntos
Cardiomiopatia Dilatada/terapia , Insuficiência Cardíaca/terapia , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco/métodos , Humanos , Masculino , Qualidade de Vida , Volume Sistólico , Transplante Autólogo , Resultado do Tratamento
8.
Neurology ; 92(8): e866-e878, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30674601

RESUMO

OBJECTIVE: To assess the feasibility, safety, and efficacy of intracoronary allogeneic cardiosphere-derived cells (CAP-1002) in patients with Duchenne muscular dystrophy (DMD). METHODS: The Halt Cardiomyopathy Progression (HOPE)-Duchenne trial is a phase I/II, randomized, controlled, open-label trial (NCT02485938). Patients with DMD >12 years old, with substantial myocardial fibrosis, were randomized (1:1) to usual care (control) or global intracoronary infusion of CAP-1002 (75 million cells). Participants were enrolled at 3 US medical centers between January and August 2016 and followed for 12 months. An independent Data and Safety Monitoring Board provided safety oversight. Cardiac function and structure were assessed by MRI, and analyzed by a blinded core laboratory. Skeletal muscle function was assessed by performance of the upper limb (PUL). RESULTS: Twenty-five eligible patients (mean age 17.8 years; 68% wheelchair-dependent) were randomized to CAP-1002 (n = 13) or control (n = 12). Incidence of treatment-emergent adverse events was similar between groups. Compared to baseline, MRI at 12 months revealed significant scar size reduction and improvement in inferior wall systolic thickening in CAP-1002 but not control patients. Mid-distal PUL improved at 12 months in 8 of 9 lower functioning CAP-1002 patients, and no controls (p = 0.007). CONCLUSIONS: Intracoronary CAP-1002 in DMD appears safe and demonstrates signals of efficacy on both cardiac and upper limb function for up to 12 months. Thus, future clinical research on CAP-1002 treatment of DMD cardiac and skeletal myopathies is warranted. CLASSIFICATION OF EVIDENCE: This phase I/II study provides Class II evidence that for patients with DMD, intracoronary CAP-1002 is feasible and appears safe and potentially effective.


Assuntos
Cardiomiopatias/terapia , Distrofia Muscular de Duchenne/terapia , Transplante de Células-Tronco/métodos , Atividades Cotidianas , Adolescente , Adulto , Células Alógenas , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Terapia Baseada em Transplante de Células e Tecidos , Estudos de Viabilidade , Fibrose , Humanos , Imageamento por Ressonância Magnética , Masculino , Distrofia Muscular de Duchenne/complicações , Distrofia Muscular de Duchenne/fisiopatologia , Miocárdio/patologia , Qualidade de Vida , Espirometria , Transplante Homólogo , Extremidade Superior/fisiopatologia , Teste de Caminhada , Adulto Jovem
9.
ASAIO J ; 65(5): 473-480, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29877888

RESUMO

The Pressure Unloading Left Ventricular Assist Vevice (PULVAD) is a novel implantable counterpulsation LVAD, designed to provide ventricular unloading with augmentation of LV performance and retention of pulsatility. We assessed the effects of the PULVAD on hemodynamics and LV mechanoenergetics in seven farm pigs with acute ischemic heart failure. The PULVAD was implanted in the thorax and was connected to the ascending aorta. The PULVAD was pneumatically driven by a standard intra-aortic balloon pump console and was electrocardiogram-synchronized to provide LV pressure unloading along with diastolic aortic pressure augmentation. Hemodynamics, indices of LV mechanoenergetics, and coronary blood flow were measured without and after brief PULVAD support. PULVAD support decreased LV afterload and improved LV mechanical performance (increased ejection fraction, stroke volume, cardiac output and maximum elastance). The PULVAD concurrently reduced LV energy consumption (decreased stroke work and pressure-volume area) and optimized LV energetic performance (improved the ratio of stroke work to pressure-volume area). PULVAD support increased mean coronary blood flow, through dramatic augmentation of diastolic blood flow. In conclusion, the PULVAD unloads the failing LV, optimizes LV mechanoenergetics, and augments coronary blood flow. These salutary effects of short-term PULVAD support provide the foundation for long-term testing.


Assuntos
Contrapulsação/instrumentação , Contrapulsação/métodos , Coração Auxiliar , Hemodinâmica/fisiologia , Função Ventricular Esquerda/fisiologia , Animais , Insuficiência Cardíaca/fisiopatologia , Suínos
11.
Hellenic J Cardiol ; 59(4): 217-222, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29292245

RESUMO

BACKGROUND: The mitochondrial Na+/Ca2+ exchanger (mNCX) has been implicated in the pathogenesis of arrhythmogenicity and myocardial reperfusion injury, rendering its inhibition a potential therapeutic strategy. We examined the effects of CGP-37157, a selective mNCX inhibitor, on arrhythmogenesis, infarct size (IS), and no reflow area (NRA) in a porcine model of ischemia-reperfusion. METHODS: Forty pigs underwent myocardial ischemia for 60 minutes, followed by 2 hours of reperfusion. Animals were randomized to receive intracoronary infusion of 0.02 mg/kg CGP-37157 or vehicle, either before ischemia (n=17) or before reperfusion (n=17). Animals were monitored for arrhythmias. Myocardial area at risk (AR), IS, and NRA were measured by histopathology. RESULTS: AR, NRA, and IS were comparable between groups. Administration of CGP-37157 before ischemia resulted in the following: (a) suppression of ventricular tachyarrhythmias (events/pig: 1.5±1.1 vs 3.5±1.9, p=0.014), (b) easier cardioversion of ventricular tachyarrhythmias (defibrillations required for cardioversion of each episode: 2.6±2.3 vs 6.2±2.1, p=0.006), and (c) decreased maximal depression of the J point (0.75±0.27 mm vs 1.75±0.82 mm, p=0.007), compared to controls. Administration of CGP-37157 before reperfusion expedited ST-segment resolution; complete ST-segment resolution within 30 minutes of reperfusion was observed in 7/8 CGP-37157-treated animals versus 1/9 controls (p=0.003). CONCLUSIONS: In a porcine model of myocardial infarction, intracoronary administration of CGP-37157 did not decrease IS or NRA. However, it suppressed ventricular arrhythmias, decreased depression of the J point during ischemia and expedited ST-segment resolution after reperfusion. These findings motivate further investigation of pharmacologic mNCX inhibition as a potential therapeutic strategy to suppress arrhythmias in the injured heart.


Assuntos
Clonazepam , Mitocôndrias Cardíacas , Traumatismo por Reperfusão Miocárdica , Trocador de Sódio e Cálcio , Taquicardia Ventricular , Tiazepinas , Animais , Feminino , Clonazepam/administração & dosagem , Clonazepam/análogos & derivados , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Injeções Intra-Arteriais , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Traumatismo por Reperfusão Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/patologia , Distribuição Aleatória , Trocador de Sódio e Cálcio/antagonistas & inibidores , Suínos , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/prevenção & controle , Tiazepinas/administração & dosagem
12.
Eur Heart J Cardiovasc Pharmacother ; 4(1): 54-63, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28633477

RESUMO

Loop diuretics are recommended for relieving symptoms and signs of congestion in patients with chronic heart failure and are administered to more than 80% of them. However, several of their effects have not systematically been studied. Numerous cohort and four interventional studies have addressed the effect of diuretics on renal function; apart from one prospective study, which showed that diuretics withdrawal is accompanied by increase in some markers of early-detected renal injury, all others converge to the conclusion that diuretics receipt, especially in high doses is associated with increased rates of renal dysfunction. Although a long standing perception has attributed a beneficial effect to diuretics in the setting of chronic heart failure, many cohort studies support that their use, especially in high doses is associated with adverse outcome. Several studies have used propensity scores in order to match diuretic and non-diuretic receiving patients; their results reinforce the notion that diuretics use and high diuretics dose are true risk factors and not disease severity markers, as some have suggested. One small, randomized study has demonstrated that diuretics decrease is feasible and safe and accompanied by a better prognosis. In conclusion, until elegantly designed, randomized trials, powered for clinical endpoints answer the unsettled issues in the field, the use of diuretics in chronic heart failure will remain subject to physicians' preferences and biases and not evidence based.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Insuficiência Cardíaca/tratamento farmacológico , Rim/efeitos dos fármacos , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico , Saúde Global , Taxa de Filtração Glomerular/efeitos dos fármacos , Insuficiência Cardíaca/mortalidade , Humanos , Rim/fisiopatologia , Taxa de Sobrevida/tendências , Resultado do Tratamento
13.
Hellenic J Cardiol ; 58(2): 135-142, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27923685

RESUMO

BACKGROUND: Left ventricular reconstruction (LVR) has been shown to provide transient benefits to the LV structure and function of infarcted hearts; however, long-term results have been disappointing as LVR-induced benefits are typically not sustained. We hypothesized that administration of cardiosphere-derived cells (CDCs), which promote myocardial repair and regeneration, may result in long-term preservation of the beneficial effects of LVR in ischemic cardiomyopathy. METHODS: Wistar Kyoto rats underwent myocardial infarction (MI) and two weeks later were randomized into 3 groups: in Group 1 (n=9), LVR was performed by plication of the infarcted apex and CDCs were injected in the infarct border zone (IBZ); group 2 animals (n=9) underwent LVR and received vehicle solution in the IBZ; and Group 3 animals (n=10) were injected with vehicle solution in the IBZ without undergoing LVR. Echocardiograms were performed at baseline, 4 days post-apex plication, and at 3 months post-MI. RESULTS: At baseline, all animal groups had a comparable LVEF, LV end-diastolic volume (EDV) and LV end-systolic volume (ESV). Four days post-LV apex plication, Group 1 and Group 2 animals exhibited comparable significant improvement in EF and comparable significant reduction in LVEDV and LVESV. Three months post-MI, Group 1 animals had a decreased LVEDV, decreased LVESV, less impaired CS, increased peak systolic torsion and increased EF compared to animals in Groups 2 and 3. CONCLUSION: In infarcted rat hearts, intramyocardial delivery of CDCs in conjunction with LVR resulted in significant and sustained amelioration of LV remodeling and improvement in LV function compared to LVR alone.

14.
Hellenic J Cardiol ; 58(4): 276-280, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27890630

RESUMO

OBJECTIVE: Chronic intermittent renal replacement therapy(RRT) is an alternate method of decongestion for patients presenting with diuretic-resistant, end-stage heart failure(HF) and cardiorenal syndrome. The optimal method of vascular access has not been confirmed. This study investigated the 6-month outcomes of patients with end-stage HF after the creation of arteriovenous communications (AVC) compared with other means of RRT. METHODS: We treated 40 patients with chronic, intermittent, ambulatory RRT, of whom 15 (37.5%; Group A) underwent creation of AVC, and 25 (62.5%; Group B) received intraperitoneal (n=6) or internal jugular catheters (n=19) with the goal of achieving body weight stabilization and relief from congestion. RESULTS: The characteristics of the two groups were similar. According to Cox regression analysis, the 6-month rate of death or re-hospitalization for HF was significantly higher in Group A (73%) than in Group B (44%); hazard ratio (HR): 2.58; 95% confidence interval (CI) 1.2-6.2; P=0.02. Over a 6-month follow-up, the cumulative survival was significantly shorter (P=0.03) in Group A (13.8±10 weeks) than in Group B (20.7±7 weeks). In the 15 patients who received AVC, the only independent predictor of adverse outcome at 6 months was serum total bilirubin concentration (HR 2.5; 95% CI 1.1-5.7, p=0.02), whereas in the 25 patients who underwent other means of RRT, pulmonary vascular resistance (PVR) was identified as a risk factor for hospitalization or death at 1-year follow-up (HR 1.26; 95% CI 1.1-1.57, p=0.04). CONCLUSION: In patients with end-stage HF, the creation of AVC for intermittent RRT was followed by a significant increase in morbidity and mortality in comparison to the safe and effective placement of permanent central venous catheters. Patients with elevated PVR seem to comprise a group at high risk for adverse outcomes after central catheter insertion.


Assuntos
Cateteres Venosos Centrais/normas , Insuficiência Cardíaca/terapia , Hemofiltração/métodos , Terapia de Substituição Renal/efeitos adversos , Disfunção Ventricular Direita/fisiopatologia , Idoso , Síndrome Cardiorrenal/terapia , Cateteres Venosos Centrais/estatística & dados numéricos , Insuficiência Cardíaca/mortalidade , Humanos , Pessoa de Meia-Idade , Mortalidade/tendências , Ensaios Clínicos Controlados não Aleatórios como Assunto/métodos , Readmissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Resistência Vascular/fisiologia , Disfunção Ventricular Direita/complicações
15.
Springerplus ; 5(1): 1568, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652141

RESUMO

Amiodarone is effective in suppressing arrhythmias in heart failure patients. We investigated the effect of long-term amiodarone administration on myocardial fibrosis and left ventricular (LV) remodeling in a porcine model of ischemic cardiomyopathy. Eighteen infarcted farm pigs were randomized to receive long-term amiodarone administration for 3 months (n = 9) or conventional follow-up (n = 9). Evolution of LV remodeling over 3 months post-myocardial infarction was examined at tissue level (myocyte size, myocardial fibrosis and vascular density assessed by whole-field digital histopathology), organ level (LV structure and function assessed by echocardiography), and systemic level (BNP and MMP-9 levels). Long-term administration of the standard anti-arrhythmic doses of amiodarone was not associated with adverse effects on myocardial fibrosis and other features of adverse cardiac remodeling. This favorable safety profile suggests that long-term anti-arrhythmic therapy with amiodarone warrants further clinical investigation in the subpopulation of heart failure patients with significantly increased burden of arrhythmias.

16.
Int J Cardiol ; 224: 90-95, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27643472

RESUMO

BACKGROUND: The Translocator Protein (TSPO) of the mitochondrial membrane has been recognized as a potential therapeutic target for mitigation of myocardial ischemia-reperfusion injury. Administration of 4-chlorodiazepam (4-CLD), a TSPO ligand, has been shown to confer acute cardioprotective effects in small animals; however, long-term studies and studies in clinically-relevant large animal models are lacking. In the present study we investigated a potential cardioprotective effect of intracoronary administration of 4-CLD in small and large animal models of ischemia-reperfusion. METHODS: Acute myocardial infarction was induced in 38 Wistar rats and 29 farm pigs by ligation of the left anterior descending coronary artery, followed by reperfusion. Animals were randomized to undergo intracoronary infusion of 2µM 4-CLD or vehicle just prior (pigs) or immediately after (rats) reperfusion. Infarcted rats were euthanized either after 1h of reperfusion (for histological assessment of the "no reflow" area) or after 60days (for serial evaluation of cardiac function and structure by echocardiography and assessment of infarct size). Infarcted pigs were euthanized after 2h of reperfusion for histological assessment of infarct size and "no reflow" area. RESULTS: In infarcted rats, intracoronary infusion of 4-CLD resulted in acute reduction of the "no reflow" area and conferred durable long-term structural and functional benefits (reduction in infarct size, attenuation of adverse remodeling, improvement in global systolic function). In infarcted pigs, intracoronary infusion of 4-CLD was well-tolerated from a hemodynamic standpoint and resulted in acute reduction in infarct size, reduction in "no reflow" area and more rapid resolution of ST-segment elevation. CONCLUSIONS: In a rat model of myocardial infarction, intracoronary administration of 4-CLD attenuated the "no reflow" phenomenon and produced long-term structural and functional benefits. In a porcine model of myocardial infarction intracoronary administration of 4-CLD did not raise safety concerns and conferred acute cardioprotective effects.


Assuntos
Benzodiazepinonas/administração & dosagem , Cardiotônicos/administração & dosagem , Vasos Coronários/diagnóstico por imagem , Modelos Animais de Doenças , Traumatismo por Reperfusão Miocárdica/diagnóstico por imagem , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Vasos Coronários/efeitos dos fármacos , Hipolipemiantes/administração & dosagem , Infusões Intra-Arteriais/métodos , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Suínos , Resultado do Tratamento
18.
Expert Opin Biol Ther ; 16(11): 1341-1352, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27484198

RESUMO

INTRODUCTION: The -once viewed as heretical- concept of the adult mammalian heart as a dynamic organ capable of endogenous regeneration has recently gained traction. However, estimated rates of myocyte turnover vary wildly and the underlying mechanisms of cardiac plasticity remain controversial. It is still unclear whether the adult mammalian heart gives birth to new myocytes through proliferation of resident myocytes, through cardiomyogenic differentiation of endogenous progenitors or through both mechanisms. AREAS COVERED: In this review, the authors discuss the cellular origins of postnatal mammalian cardiomyogenesis and touch upon therapeutic strategies that could potentially amplify innate cardiac regeneration. EXPERT OPINION: The adult mammalian heart harbors a limited but detectable capacity for spontaneous endogenous regeneration. During normal aging, proliferation of pre-existing cardiomyocytes is the dominant mechanism for generation of new cardiomyocytes. Following myocardial injury, myocyte proliferation increases modestly, but differentiation of endogenous progenitor cells appears to also contribute to cardiomyogenesis (although agreement on the latter point is not universal). Since cardiomyocyte deficiency underlies almost all types of heart disease, development of therapeutic strategies that amplify endogenous regeneration to a clinically-meaningful degree is of utmost importance.

19.
J Card Surg ; 31(7): 467-71, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27196808

RESUMO

BACKGROUND: The intra-aortic balloon pump (IABP) can be used to bridge critically ill end-stage heart failure patients to left ventricular assist device (LVAD) implantation. However, the IABP's potential association with hemorrhagic complications raises concerns regarding its utilization in these patients. AIM: We investigated whether preoperative long-term IABP support increases hemorrhagic complications post-LVAD implantation. METHODS: Ten patients undergoing IABP support prior to LVAD implantation (IABP-LVAD group) were compared with 16 who did not require IABP support (LVAD group). RESULTS: Mean duration of IABP support was 25.8 days. Preoperatively, both groups were comparable in all measured parameters and indices of end-organ function. Perioperative (defined as three weeks post-LVAD implantation, including the procedure) cellular and noncellular blood transfusion requirements were similar between IABP-LVAD and LVAD groups (19.8 ± 9.95 vs. 19.76 ± 29.69 RBC units, p = 0.96; 3.8 ± 4.14 vs. 2.0 ± 6.44 plateletpheresis units p = 0.84; 23 ± 16.04 vs. 25.14 ± 37.8 fresh frozen plasma units, p = 0.45). Perioperative minimum hematocrit (33.6 ± 5.6 vs. 36.59 ± 4.8, p = 0.38) and minimum platelet count (199 ± 153 vs. 144 ± 65, p = 0.52) were similar in the two groups. Two patients in the IABP-LVAD group and three patients in the LVAD group underwent reoperation post-LVAD implantation for bleeding. Length of ICU stay was longer in the LVAD group but did not reach statistical significance (6.2 ± 6.22 days in the IABP-LVAD group versus 13.45 ± 10.95 days in the LVAD group, p = 0.06). CONCLUSIONS: Long-term IABP support as a bridge to LVAD implantation is not associated with increased hemorrhagic complications post-LVAD implantation. doi: 10.1111/jocs.12759 (J Card Surg 2016;31:467-471).


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Hemorragia/etiologia , Balão Intra-Aórtico/efeitos adversos , Implantação de Prótese , Adulto , Feminino , Hemorragia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
20.
World J Transplant ; 6(1): 115-24, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27011909

RESUMO

Cardiac recovery from cardiogenic shock (CS) and end-stage chronic heart failure (HF) remains an often insurmountable therapeutic challenge. The counterpulsation technique exerts numerous beneficial effects on systemic hemodynamics and left ventricular mechanoenergetics, rendering it attractive for promoting myocardial recovery in both acute and chronic HF. Although a recent clinical trial has questioned the clinical effectiveness of short-term hemodynamic support with intra-aortic balloon pump (IABP, the main representative of the counterpulsation technique) in CS complicating myocardial infarction, the issue remains open to further investigation. Moreover, preliminary data suggest that long-term IABP support in patients with end-stage HF is safe and may mediate recovery of left- or/and right-sided cardiac function, facilitating long-term weaning from mechanical support or enabling the application of other permanent, life-saving solutions. The potential of long-term counterpulsation could possibly be enhanced by implementation of novel, fully implantable counterpulsation devices.

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