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BACKGROUND: Transthyretin amyloidosis with cardiomyopathy (ATTR-CM) is a progressive, fatal disease. Vutrisiran, a subcutaneously administered RNA interference therapeutic agent, inhibits the production of hepatic transthyretin. METHODS: In this double-blind, randomized trial, we assigned patients with ATTR-CM in a 1:1 ratio to receive vutrisiran (25 mg) or placebo every 12 weeks for up to 36 months. The primary end point was a composite of death from any cause and recurrent cardiovascular events. Secondary end points included death from any cause, the change from baseline in the distance covered on the 6-minute walk test, and the change from baseline in the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS) score. The efficacy end points were assessed in the overall population and in the monotherapy population (the patients who were not receiving tafamidis at baseline) and were tested hierarchically. RESULTS: A total of 655 patients underwent randomization; 326 were assigned to receive vutrisiran and 329 to receive placebo. Vutrisiran treatment led to a lower risk of death from any cause and recurrent cardiovascular events than placebo (hazard ratio in the overall population, 0.72; 95% confidence interval [CI], 0.56 to 0.93; P = 0.01; hazard ratio in the monotherapy population, 0.67; 95% CI, 0.49 to 0.93; P = 0.02) and a lower risk of death from any cause through 42 months (hazard ratio, 0.65; 95% CI, 0.46 to 0.90; P = 0.01). A primary end-point event occurred in 163 patients in the vutrisiran group and in 202 in the placebo group. In the overall population, treatment with vutrisiran resulted in less of a decline in the distance covered on the 6-minute walk test than placebo (least-squares mean difference, 26.5 m; 95% CI, 13.4 to 39.6; P<0.001) and less of a decline in the KCCQ-OS score (least-squares mean difference, 5.8 points; 95% CI, 2.4 to 9.2; P<0.001). Similar benefits were observed in the monotherapy population. The incidence of adverse events was similar in the two groups (99% in the vutrisiran group and 98% in the placebo group); serious adverse events occurred in 62% of the patients in the vutrisiran group and in 67% of those in the placebo group. CONCLUSIONS: Among patients with ATTR-CM, treatment with vutrisiran led to a lower risk of death from any cause and cardiovascular events than placebo and preserved functional capacity and quality of life. (Funded by Alnylam Pharmaceuticals; HELIOS-B ClinicalTrials.gov number, NCT04153149.).
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BACKGROUND: Coronary allograft vasculopathy (CAV) remains a significant cause of morbidity and mortality after heart transplantation. The use of aspirin for CAV prophylaxis has recently garnered interest as a possible therapeutic adjunct in this setting. METHODS: This 2-center retrospective cohort study included 372 patients who underwent heart transplantation between January 2009 and March 2018 and were stratified according to the commencement of aspirin during their index transplant admission. The primary outcome was the development of moderate or severe CAV (International Society for Heart and Lung Transplantation grade ≥2) at surveillance coronary angiography. Secondary endpoints included mortality at follow-up. RESULTS: There were no differences in age, sex, and cause of heart failure. In the early aspirin group, the preponderant risk factors included use of ventricular assist devices, pretransplant smoking, and mild or moderate rejection. Multivariable analyses to assess for independent predictors of CAV development and mortality demonstrated that aspirin was associated with reduced mortality (adjusted hazard ratioâ =â 0.19; 95% confidence interval, 0.08-0.47, Pâ <â 0.01) and a trend toward a protective effect against the development of moderate or severe CAV (adjusted hazard ratioâ =â 0.24; 95% confidence interval, 0.54-1.19; Pâ =â 0.08). CONCLUSIONS: In this retrospective risk-adjusted 2-center cohort study, early aspirin administration was associated with reduced risk of death and a trend toward a protective effect against CAV development. These findings warrant validation in prospective randomized trials.
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BACKGROUND: Heart transplantation is an effective treatment for end-stage congestive heart failure, however, achieving the right balance of immunosuppression to maintain graft function while minimising adverse effects is challenging. Serial endomyocardial biopsies (EMBs) are currently the standard for rejection surveillance, despite being invasive. Replacing EMB-based surveillance with cardiac magnetic resonance (CMR)-based surveillance for acute cardiac allograft rejection has shown feasibility. This study aimed to assess the cost-effectiveness of CMR-based surveillance in the first year after heart transplantation. METHOD: A prospective clinical trial was conducted with 40 orthotopic heart transplant (OHT) recipients. Participants were randomly allocated into two surveillance groups: EMB-based, and CMR-based. The trial included economic evaluations, comparing the frequency and cost of surveillance modalities in relation to quality-adjusted life years (QALYs) within the first year post-transplantation. Sensitivity analysis encompassed modelled data from observed EMB and CMR arms, integrating two hypothetical models of expedited CMR-based surveillance. RESULTS: In the CMR cohort, 238 CMR scans and 15 EMBs were conducted, versus (vs) 235 EMBs in the EMB group. CMR surveillance yielded comparable rejection rates (CMR 74 vs EMB 94 events, p=0.10) and did not increase hospitalisation risk (CMR 32 vs EMB 46 events, p=0.031). It significantly reduced the necessity for invasive EMBs by 94%, lowered costs by an average of AUD$32,878.61, and enhanced cumulative QALY by 0.588 compared with EMB. Sensitivity analysis showed that increased surveillance with expedited CMR Models 1 and 2 were more cost-effective than EMB (all p<0.01), with CMR Model 1 achieving the greatest cost savings (AUD$34,091.12±AUD$23,271.86 less) and utility increase (+0.62±1.49 QALYs, p=0.011), signifying an optimal cost-utility ratio. Model 2 showed comparable utility to the base CMR model (p=0.900) while offering the benefit of heightened surveillance frequency during periods of elevated rejection risk. CONCLUSIONS: CMR-based rejection surveillance in orthotopic heart transplant recipients provides a cost-effective alternative to EMB-based surveillance. Furthermore, it reduces the need for invasive procedures, without increased risk of rejection or hospitalisation for patients, and can be incorporated economically for expedited surveillance. These findings have important implications for improving patient care and optimising resource allocation in post-transplant management.
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Rejeição de Enxerto , Transplante de Coração , Humanos , Transplante de Coração/economia , Rejeição de Enxerto/economia , Rejeição de Enxerto/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Austrália/epidemiologia , Estudos Prospectivos , Análise Custo-Benefício , Adulto , Imagem Cinética por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/economia , Anos de Vida Ajustados por Qualidade de Vida , Seguimentos , Imageamento por Ressonância Magnética/economia , Imageamento por Ressonância Magnética/métodosRESUMO
Aims: Unstable atherosclerotic plaques have increased activity of myeloperoxidase (MPO). We examined whether molecular magnetic resonance imaging (MRI) of intraplaque MPO activity predicts future atherothrombosis in rabbits and correlates with ruptured human atheroma. Methods and results: Plaque MPO activity was assessed in vivo in rabbits (n = 12) using the MPO-gadolinium (Gd) probe at 8 and 12 weeks after induction of atherosclerosis and before pharmacological triggering of atherothrombosis. Excised plaques were used to confirm MPO activity by liquid chromatography-tandem mass spectrometry (LC-MSMS) and to determine MPO distribution by histology. MPO activity was higher in plaques that caused post-trigger atherothrombosis than plaques that did not. Among the in vivo MRI metrics, the plaques' R1 relaxation rate after administration of MPO-Gd was the best predictor of atherothrombosis. MPO activity measured in human carotid endarterectomy specimens (n = 30) by MPO-Gd-enhanced MRI was correlated with in vivo patient MRI and histological plaque phenotyping, as well as LC-MSMS. MPO-Gd retention measured as the change in R1 relaxation from baseline was significantly greater in histologic and MRI-graded American Heart Association (AHA) type VI than type III-V plaques. This association was confirmed by comparing AHA grade to MPO activity determined by LC-MSMS. Conclusion: We show that elevated intraplaque MPO activity detected by molecular MRI employing MPO-Gd predicts future atherothrombosis in a rabbit model and detects ruptured human atheroma, strengthening the translational potential of this approach to prospectively detect high-risk atherosclerosis.
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Autologous haematopoietic stem cell transplantation is now well-established as an effective treatment for severe systemic sclerosis with clear demonstration of favourable end-organ and survival outcomes. Treatment-related cardiotoxicity remains the predominant safety concern and contraindicates autologous haematopoietic stem cell transplantation in patients with severe cardiopulmonary disease. In this review, we describe the cardiovascular outcomes of autologous haematopoietic stem cell transplantation recipients, discuss the potential mechanisms of cardiotoxicity and propose future mitigating strategies.
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BACKGROUND: Although modern immunosuppressants improve survival post-transplant, they are associated with long-term metabolic complications, such as post-transplant diabetes mellitus (PTDM). Calcineurin inhibitor-sparing regimens using everolimus attenuate some complications such as left ventricular hypertrophy. However, the metabolic effects of everolimus following transplant are less clear. METHODS: Post-hoc analysis to compare PTDM and other metabolic outcomes in participants of a randomised open-label clinical trial of low-dose everolimus and tacrolimus versus standard-dose tacrolimus in heart transplant recipients (RADTAC1 study). RESULTS: There were 39 participants in the trial; mean follow-up was 6.4±1.5 years. There was a high rate of pre-existing diabetes (26%) and newly diagnosed PTDM (36%) during follow-up. Half the patients who developed PTDM in the everolimus-tacrolimus group (n=4/8) ceased diabetes medications during follow-up, which was not observed in patients on standard tacrolimus (n=0/6). In the first 12 months there was a higher use of non-insulin treatment for diabetes in the everolimus-tacrolimus group compared to the standard tacrolimus group. CONCLUSIONS: This study suggests that treatment with everolimus may be associated with improved glycaemic control of PTDM relative to treatment with standard doses of calcineurin inhibitor. These findings should be further studied in prospective randomised trials.
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Diabetes Mellitus , Transplante de Coração , Humanos , Everolimo , Tacrolimo/uso terapêutico , Inibidores de Calcineurina/efeitos adversos , Estudos Prospectivos , Progressão da Doença , Rejeição de EnxertoRESUMO
Changes in atrial size and function have historically been considered a surrogate marker of ventricular dysfunction. However, it is now recognized that atrial cardiomyopathy (ACM) may also occur as a primary myocardial disorder. Emerging evidence that ACM is a major risk factor for atrial fibrillation, heart failure, and thromboembolic stroke, has highlighted the significance of this disorder and the need for better assessment of atrial metrics in clinical practice. Key barriers in this regard include a lack of standardized criteria or hierarchy for the diagnosis of ACM and lack of consensus for the most accurate phenotyping methods. In this article we review existing literature on ACM, with a focus on current and future non-invasive imaging methods for detecting abnormalities of atrial structure and function. We discuss the relative advantages and disadvantages of transthoracic echocardiography and cardiac magnetic resonance imaging for assessing a range of parameters, including atrial size and contractile function, strain, tissue characteristics, and epicardial adipose tissue. We will also present the potential application of novel imaging methods such as sphericity index and four- or five-dimensional flow.
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Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Vasos Coronários/diagnóstico por imagem , Valor Preditivo dos Testes , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia Coronária/métodos , Angiografia por Tomografia Computadorizada/métodosRESUMO
It is of increasing importance to understand and predict changes to the systemic and pulmonary circulations in pulmonary hypertension (PH). To do so, it is necessary to describe the circulation in complete quantitative terms. Characteristic impedance (Zc) expresses opposition of the circulation to pulsatile blood flow. Evaluation of systemic and pulmonary Zc relationships according to PH classification has not previously been described. Prospective study of 40 clinically indicated patients referred for CMR and RHC (56 ± 18 years; 70% females, eight mPAP ≤ 25 mmHg, 16 pre-capillary [Pre-cPH], eight combined pre- and post-capillary [Cpc-PH] and eight isolated left-heart disease [Ipc-PH]). CMR provided assessment of ascending aortic (Ao) and pulmonary arterial (PA) flow, and RHC, central Ao and PA pressure. Systemic and pulmonary Zc were expressed as the relationship of pressure to flow in the frequency domain. Baseline demographic characteristics were well-matched across PH subclasses. In those with a mPAP ≤25mHg, systemic Zc and SVR were >2 times higher than pulmonary Zc and PVR. Only Pre-cPH was associated with inverse pulsatile (systemic Zc 58 [45-69] vs pulmonary Zc 70 [58-85]), but not steady-state (SVR 1101 [986-1752] vs. PVR 483 [409-557]) relationships. Patients with CpcPH and IpcPH had concordant pulsatile and steady-state relationships (Graphical Abstract). Measurement of, and the relationship between, systemic and pulmonary Zc in patients according to PH sub-classification has not previously been described. Systemic Zc was routinely higher than pulmonary Zc, except in patients with newly diagnosed Pre-cPH, where inverse pulsatile but not steady-state relationships were observed.
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Hipertensão Pulmonar , Feminino , Humanos , Masculino , Estudos Prospectivos , Hemodinâmica/fisiologia , Coração , Circulação Pulmonar , Resistência VascularRESUMO
INTRODUCTION: Cardiac transplantation (CTx) is a life-saving operation that can improve the quality and length of a recipient's life. Immunosuppression medication, required to prevent rejection, can result in adverse metabolic and renal effects. Clinically significant complications include metabolic effects such as diabetes and weight gain, renal impairment, and cardiac disease such as allograft vasculopathy and myocardial fibrosis. Sodium glucose co-transporter 2 (SGLT2) inhibitors are a class of oral medication that increase urinary excretion of glucose. In patients with type 2 diabetes, SGLT2 inhibitors improve cardiovascular, metabolic and renal outcomes. Similar benefits have been shown in patients with heart failure and reduced ejection fraction irrespective of diabetes status. In patients with post-transplant diabetes mellitus, SGLT2 inhibitors improve metabolic parameters; however, their benefit and safety have not been evaluated in randomised prospective studies. This study will potentially provide a novel therapy to improve or prevent complications (diabetes, kidney failure and heart fibrosis) that occur with immunosuppressive medications. METHODS: The EMPA-HTx study is a randomised, placebo-controlled trial of the SGLT2 inhibitor empagliflozin 10 mg daily versus placebo in recent CTx recipients. One hundred participants will be randomised 1:1 and commence the study medication within 6-8 weeks of transplantation with treatment and follow-up until 12 months after transplantation. Demographic information, anthropomorphic measurements, pathology tests and cardiac magnetic resonance (CMR) scan will be recorded at baseline and follow-up. Patients will be reviewed monthly during the study until 12 months post-CTx and data will be collected for each patient at each study visit. The overall aim of the study is to assess the safety and efficacy of empagliflozin in CTx recipients. The primary outcome is glycaemic improvement measured as change in glycated haemoglobin and/or fructosamine. Key secondary outcomes are cardiac interstitial fibrosis measured by CMR and renal function measured by estimated glomerular filtration rate. ETHICS AND DISSEMINATION: This study has been approved by St Vincent's Hospital Human Research Ethics Committee (2021/ETH12184). The findings will be presented at national and international scientific meetings and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ACTRN12622000978763.
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Diabetes Mellitus Tipo 2 , Transplante de Coração , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/complicações , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Hipoglicemiantes/uso terapêutico , Transportador 2 de Glucose-Sódio/uso terapêutico , Estudos Prospectivos , Compostos Benzidrílicos/uso terapêutico , Rim/fisiologia , Glucose/uso terapêutico , Sódio/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: Tricuspid regurgitation (TR) is common following heart transplantation and has been shown to adversely influence patient outcomes. The aim of this study was to identify causes of progression to moderate-severe TR in the first 2 y after transplantation. METHODS: This was a retrospective, single-center study of all patients who underwent heart transplantation over a 6-y period. Transthoracic echocardiogram (TTE) was performed at month 0, between 6 and 12 mo, and 1-2 y postoperatively to determine the presence and severity of TR. RESULTS: A total of 163 patients were included, of whom 142 underwent TTE before first endomyocardial biopsy. At month 0, 127 (78%) patients had nil-mild TR before first biopsy, whereas 36 (22%) had moderate-severe TR. In patients with nil-mild TR, 9 (7%) progressed to moderate-severe TR by 6 mo and 1 underwent tricuspid valve (TV) surgery. Of patients with moderate-severe TR before first biopsy, by 2 y, 3 had undergone TV surgery. The use of postoperative extracorporeal membrane oxygenation (ECMO) in the latter group was significant (78%; P < 0.05) as was rejection profile ( P = 0.02). Patients with late progressive moderate-severe TR had a significantly higher 2-y mortality than those who had moderate-severe TR immediately. CONCLUSIONS: Overall, our study has shown that in the 2 main groups of interest (early moderate-severe TR and progression from nil-mild to moderate-severe TR), TR is more likely to be the result of significant underling graft dysfunction rather than the cause of it.
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Transplante de Coração , Insuficiência da Valva Tricúspide , Humanos , Insuficiência da Valva Tricúspide/etiologia , Insuficiência da Valva Tricúspide/cirurgia , Estudos Retrospectivos , Transplante de Coração/efeitos adversos , Ecocardiografia/efeitos adversos , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: The effect of pulmonary hypertension (PH) on right ventricular (RV) afterload is commonly defined by elevation of pulmonary artery (PA) pressure or pulmonary vascular resistance (PVR). In humans however, one-third to half of the hydraulic power in the PA is contained in pulsatile components of flow. Pulmonary impedance (Zc) expresses opposition of the PA to pulsatile blood flow. We evaluate pulmonary Zc relationships according to PH classification using a cardiac magnetic resonance (CMR)/right heart catheterization (RHC) method. METHODS: Prospective study of 70 clinically indicated patients referred for same-day CMR and RHC [60 ± 16 years; 77% females, 16 mPAP <25 mmHg (PVR <240 dynes.s.cm-5 /mPCWP <15 mmHg), 24 pre-capillary (PrecPH), 15 isolated post-capillary (IpcPH), 15 combined pre-capillary/post-capillary (CpcPH)]. CMR provided assessment of PA flow, and RHC, central PA pressure. Pulmonary Zc was expressed as the relationship of PA pressure to flow in the frequency domain (dynes.s.cm-5 ). RESULTS: Baseline demographic characteristics were well matched. There was a significant difference in mPAP (P < 0.001), PVR (P = 0.001), and pulmonary Zc between mPAP<25 mmHg patients and those with PH (mPAP <25 mmHg: 47 ± 19 dynes.s.cm-5 ; PrecPH 86 ± 20 dynes.s.cm-5 ; IpcPH 66 ± 30 dynes.s.cm-5 ; CpcPH 86 ± 39 dynes.s.cm-5 ; P = 0.05). For all patients with PH, elevated mPAP was found to be associated with raised PVR (P < 0.001) but not with pulmonary Zc (P = 0.87), except for those with PrecPH (P < 0.001). Elevated pulmonary Zc was associated with reduced RVSWI, RVEF, and CO (all P < 0.05), whereas PVR and mPAP were not. CONCLUSIONS: Raised pulmonary Zc was independent of elevated mPAP in patients with PH and more strongly predictive of maladaptive RV remodelling than PVR and mPAP. Use of this straightforward method to determine pulmonary Zc may help to better characterize pulsatile components of RV afterload in patients with PH than mPAP or PVR alone.
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Hipertensão Pulmonar , Disfunção Ventricular Direita , Feminino , Humanos , Masculino , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/diagnóstico , Prognóstico , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/etiologia , Estudos Prospectivos , Impedância ElétricaRESUMO
BACKGROUND: In the setting of the COVID-19 pandemic, a rapid uptake of telehealth services was instituted with the aim of reducing the spread of disease to vulnerable patient populations including heart transplant recipients. METHODS: Single-center, cohort study of all heart transplant patients seen by our institution's transplant program during the first 6 weeks of transition from in-person consultation to telehealth (23 March - 5 June 2020). RESULTS: Face-to-face consultation allocation strongly favored patients in the early post-operative period (34 vs. 242 weeks post-transplant; p < 0.001). Telehealth consultation dramatically reduced patient travel and wait times (80â min per visit saved in telehealth patients). No apparent excess re-hospitalization or mortality was seen in telehealth patients. CONCLUSIONS: With appropriate triage, telehealth was feasible in heart transplant recipients, with videoconferencing being the preferred modality. Patients seen face-to-face were those triaged to be higher acuity based on time since transplant and overall clinical status. These patients have the expected higher rates of hospital re-admission, and therefore should continue to be seen in person.
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The effect of arterial stiffening on elevated pulsatile left ventricular afterload patients with aortic stenosis (AS) is pronounced beyond systemic hypertension. Circulatory afterload pulsatile efficiency (CAPE) is a marker of vascular function, defined as the ratio of steady state energy consumption (SEC) to maintain systemic circulation and pulsatile energy consumption (PEC). Twenty patients aged 80 ± 7 years were assessed at baseline and a median of 60 days post transcatheter aortic valve replacement (TAVR), with pulsatile vascular load calculated using simultaneous radial applanation tonometry derived aortic pressure and cardiac magnetic resonance phase-contrast imaging derived ascending aortic flow. Eight out of 20 patients had a reduction in PEC post TAVR, and the reduction of PEC correlated strongly with the number of days post TAVR (R = 0.62, P < 0.01). Patients assessed within the 100 days of TAVR had a rise in their PEC when compared to baseline (0.19 ± 0.09 vs 0.14 ± 0.08 W, P = 0.04). Baseline PEC correlated moderately with baseline SEC (R = 0.49, P = 0.03), and a high baseline PEC was predictive of post TAVR PEC reduction (R = 0.54, P =0.01). Overall, no significant differences were found between baseline and post TAVR for systolic aortic pressure (131 ± 20 vs 131 ± 20 mmHg), systemic vascular resistance (1894 ± 493 vs 2015 ± 519 dynes.s/cm5), aortic valve ejection time (337 ± 22 vs 324 ± 34 ms) or aortic characteristic impedance (120 ± 48 vs 107 ± 41 dynes.s/cm5). Improved flow profiles after TAVR likely unmask the true vascular properties by altering ventriculo-valvulo-arterial coupling, leading to downstream vascular remodelling secondary to flow conditioning, and results in eventual improvement of pulsatile afterload as reflected by our proposed index of CAPE.
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Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Resultado do Tratamento , Função Ventricular Esquerda , Biomarcadores , Índice de Gravidade de DoençaRESUMO
There is accumulating evidence that novel glucose-lowering agents infer potent cardiovascular and renal benefits. Therefore, it is imperative to reassess the management of post-transplant diabetes mellitus and consider the role of newer agents. With improved transplant-related survival and high prevalence of post-transplant diabetes, management of long-term complications such as diabetes are increasingly important. There are limited guidelines to assist in choice of appropriate agents after solid organ transplantation. Traditional therapies including insulin and sulfonylureas may still have a role; however, other agents should be considered prior. The evidence of novel glucose-lowering agents in post-transplant care is limited, and most studies have focused on kidney transplant recipients. While there are some parallels between renal and cardiac transplant recipients, the potential cardiovascular benefits, particularly on cardiac fibrosis are unique to cardiac transplantation. The treatment of diabetes, with a focus on additional cardiac and renal benefits, needs to be brought to the forefront of post-transplant care with incorporation of recent evidence outside of transplantation. The role for novel glucose-lowering agents in cardiac transplant recipients will be explored, with a summary of available evidence.
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Cardiologistas , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Transplante de Coração , Humanos , Endocrinologistas , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/etiologia , Transplante de Coração/efeitos adversos , Glucose , Diabetes Mellitus Tipo 2/complicaçõesRESUMO
Intracellular myeloperoxidase (MPO) plays a specific role in the innate immune response; however, upon release into the extracellular space in the setting of inflammation, drives oxidative tissue injury. Extracellular MPO has recently been shown to be abundant in unstable atheroma and causally linked to plaque destabilization, erosion, and rupture, identifying it as a potential target for the surveillance and treatment of vulnerable atherosclerosis. Through the compartmentalization of MPO's protective and deleterious effects, extracellular MPO can be selectively detected using non-invasive molecular imaging and targeted by burgeoning pharmacotherapies. Given its causal relationship to plaque destabilization coupled with an ability to preserve its beneficial properties, MPO is potentially a superior translational inflammatory target compared with other immunomodulatory therapies and imaging biomarkers utilized to date. This review explores the role of MPO in plaque destabilization and provides insights into how it can be harnessed in the management of patients with vulnerable atherosclerotic plaque.
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Aterosclerose , Placa Aterosclerótica , Humanos , Peroxidase , Aterosclerose/etiologia , Artérias , Inflamação/complicaçõesRESUMO
Heart transplantation from donation after circulatory death (DCD) donors has the potential to substantially increase overall heart transplant activity. The aim of this report is to review the first 8 y of our clinical heart transplant program at St Vincent's Hospital Sydney, to describe how our program has evolved and to report the impact that changes to our retrieval protocols have had on posttransplant outcomes. Since 2014, we have performed 74 DCD heart transplants from DCD donors utilizing a direct procurement protocol followed by normothermic machine perfusion. Changes to our retrieval protocol have resulted in a higher retrieval rate from DCD donors and fewer rejections of DCD hearts during normothermic machine perfusion. Compared with our previously reported early experience in the first 23 transplants, we have observed a significant reduction in the incidence of severe primary graft dysfunction from 35% (8/23) to 8% (4/51) in the subsequent 51 transplant recipients ( P < 0.01). The only withdrawal time interval significantly associated with severe primary graft dysfunction was the asystolic warm ischemic time: 15 (12-17) versus 13 (11-14) min ( P < 0.05). One- and 5-y survival of DCD heart transplant recipients was 94% and 88%, comparable to that of a contemporary cohort of donation after brain death recipients: 87 and 81% ( P -value was not significant). In conclusion, heart transplantation from DCD donors has become a major contributor to our overall transplant activity accounting for almost 30% of all transplants performed by our program in the last 2 y, with similar DCD and donation after brain death outcomes.
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Transplante de Coração , Disfunção Primária do Enxerto , Obtenção de Tecidos e Órgãos , Humanos , Morte Encefálica , Doadores de Tecidos , Transplante de Coração/efeitos adversos , Transplante de Coração/métodos , Sobrevivência de Enxerto , Estudos Retrospectivos , MorteRESUMO
Background: The detection of unstable atherosclerosis remains elusive. Intraplaque myeloperoxidase (MPO) activity causes plaque destabilization in preclinical models, holding promise for clinical translation as a novel imaging biomarker. Objectives: The purpose of this study was to assess whether MPO activity is greater in unstable human plaques, how this relates to cardiovascular events and current/emerging non-invasive imaging techniques. Methods: Thirty-one carotid endarterectomy specimens and 12 coronary trees were collected. MPO activity was determined in 88 individual samples through the conversion of hydroethidine to the MPO-specific adduct 2-chloroethidium and compared with macroscopic validation, histology, clinical outcomes, and computed tomography-derived high and low attenuation plaques and perivascular adipose tissue. Non-parametric statistical analysis utilizing Mann-Whitney U and Kruskal-Wallis tests for univariate and group comparisons were performed. Results: Unstable compared with stable plaque had higher MPO activity (carotid endarterectomy: n = 26, 4.2 ± 3.1 vs 0.2 ± 0.3 nmol/mgp; P < 0.0001; coronary: n = 17, 0.6 ± 0.5 vs 0.001 ± 0.003 nmol/mgp; P = 0.0006). Asymptomatic, stroke-free patients had lower MPO activity compared to those with symptoms or ipsilateral stroke (n = 12, 3.7 ± 2.1 vs 0.1 ± 0.2 nmol/mgp; P = 0.002). Computed tomography-determined plaque attenuation did not differentiate MPO activity (n = 30, 0.1 ± 0.1 vs 0.2 ± 0.3 nmol/mgp; P = 0.23) and MPO activity was not found in perivascular adipose tissue. Conclusions: MPO is active within unstable human plaques and correlates with symptomatic carotid disease and stroke, yet current imaging parameters do not identify plaques with active MPO. As intraplaque MPO activity can be imaged non-invasively through novel molecular imaging probes, ongoing investigations into its utility as a diagnostic tool for high-risk atherosclerosis is warranted.
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Cardiac light chain (AL) amyloidosis is a condition with a very poor prognosis. We report a retrospective analysis comparing the traditional melphalan and dexamethasone protocol with cyclophosphamide, bortezomib and dexamethasone in late-stage cardiac AL amyloidosis. The primary end points were overall survival and haematological response. Both regimens provided meaningful responses in this difficult to treat patient group.