Drug Therapy in the Heart Transplant Recipient

The value of extracorporeal photopheresis as an immunosuppression-modifying approach in solid organ transplantation: a potential solution to an unmet medical need

Allograft rejection is a critical issue following solid organ transplantation (SOT). Immunosuppressive therapies are crucial in reducing risk of rejection yet are accompanied by several significant side effects, including infection, malignancy, cardiovascular diseases, and nephrotoxicity. There is a current unmet medical need with a lack of effective minimization strategies for these side effects. Extracorporeal photopheresis (ECP) has shown potential as an immunosuppression (IS)-modifying technique in several SOT types, with improvements seen in acute and recurrent rejection, allograft survival, and associated side effects, and could fulfil this unmet need. Through a review of the available literature detailing key areas in which ECP may benefit patients, this review highlights the IS-modifying potential of ECP in the four most common SOT procedures (heart, lung, kidney, and liver transplantation) and highlights existing gaps in data. Current evidence supports the use of ECP for IS modification following SOT, however there is a need for further high-quality research, in particular randomized control trials, in this area.

Induction therapy in heart transplantation: A systematic review and network meta-analysis for developing evidence-based recommendations

INTRODUCTION

Induction therapy (IT) utility in heart transplantation (HT) remains contested. Commissioned by a clinical-practice guidelines panel to evaluate the effectiveness and safety of IT in adult HT patients, we conducted this systematic review and network meta-analysis (NMA).

METHODS

We searched for studies from January 2000 to October 2022, reporting on the use of any IT agent in adult HT patients. Based on patient-important outcomes, we performed frequentist NMAs separately for RCTs and observational studies with adjusted analyses, and assessed the certainty of evidence using the GRADE framework.

RESULTS

From 5156 publications identified, we included 7 RCTs and 12 observational studies, and report on two contemporarily-used IT agents-basiliximab and rATG. The RCTs provide only very low certainty evidence and was uninformative of the effect of the two agents versus no IT or one another. With low certainty in the evidence from observational studies, basiliximab may increase 30-day (OR 1.13; 95% CI 1.06-1.20) and 1-year (OR 1.11; 95% CI 1.02-1.22) mortality compared to no IT. With low certainty from observational studies, rATG may decrease 5-year cardiac allograft vasculopathy (OR .82; 95% CI .74-.90) compared to no IT, as well as 30-day (OR .85; 95% CI .80-.92), 1-year (OR .87; 95% CI .79-.96), and overall (HR .84; 95% CI .76-.93) mortality compared to basiliximab.

CONCLUSION

With low and very low certainty in the synthetized evidence, these NMAs suggest possible superiority of rATG compared to basiliximab, but do not provide compelling evidence for the routine use of these agents in HT recipients.

Use of induction therapy post-heart transplantation: Clinical practice recommendations based on systematic review and network meta-analysis of evidence

BACKGROUND

The use of induction therapy (IT) agents in the early post-heart transplant period remains controversial. The following recommendations aim to provide guidance on the use of IT agents, including Basiliximab and Thymoglobulin, as part of routine care in heart transplantation (HTx).

METHODS

We recruited an international, multidisciplinary panel of 15 stakeholders, including patient partners, transplant cardiologists and surgeons, nurse practitioners, pharmacists, and methodologists. We commissioned a systematic review on benefits and harms of IT on patient-important outcomes, and another on patients' values and preferences to inform our recommendations. We used the GRADE framework to summarize our findings, rate certainty in the evidence, and develop recommendations. The panel considered the balance between benefits and harms, certainty in the evidence, and patient's values and preferences, to make recommendations for or against the routine post-operative use of Thymoglobulin or Basiliximab.

RESULTS

The panel made recommendations on three major clinical problems in HTx: (1) We suggest against the routine post-operative use of Basiliximab compared to no IT, (2) we suggest against the routine use of Thymoglobulin compared to no IT, and (3) for those patients for whom IT is deemed desirable, we suggest for the use of Thymoglobulin as compared to Basiliximab.

CONCLUSION

This report highlights gaps in current knowledge and provides directions for clinical research in the future to better understand the clinical utility of IT agents in the early post heart transplant period, leading to improved management and care.

Heart Transplantation

Heart transplantation (HTx) remains the last therapeutic resort for patients with advanced heart failure. The present work is a clinically focused review discussing current issues in heart transplantation. Several factors have been associated with the outcome of HTx, such as ABO and HLA compatibility, graft size, ischemic time, age, infections, and the cause of death, as well as imaging and laboratory tests. In 2018, UNOS changed the organ allocation policy for HTx. The aim of this change was to prioritize patients with a more severe clinical condition resulting in a reduction in mortality of people on the waiting list. Advanced heart failure and resistant angina are among the main indications of HTx, whereas active infection, peripheral vascular disease, malignancies, and increased body mass index (BMI) are important contraindications. The main complications of HTx include graft rejection, graft angiopathy, primary graft failure, infection, neoplasms, and retransplantation. Recent advances in the field of HTx include the first two porcine-to-human xenotransplantations, the inclusion of hepatitis C donors, donation after circulatory death, novel monitoring for acute cellular rejection and antibody-mediated rejection, and advances in donor heart preservation and transportation. Lastly, novel immunosuppression therapies such as daratumumab, belatacept, IL 6 directed therapy, and IgG endopeptidase have shown promising results.

Dental care for cardiac transplant patients in the UK

Cardiac transplantation replaces a severely damaged non-functioning heart with a healthy heart from a donor. Within the UK, the number of cardiac transplants being performed each year is increasing, with significant improvements in longer-term survival. Dental professionals are therefore more likely to see and manage these patients in the pre- and post-transplant periods. This paper proposes a protocol for the dental management of these patients, reinforced by a case series from Scotland and London.

Cost-Effectiveness of Tacrolimus Compared With Cyclosporine for Immunosuppression Therapy in Patients Who Underwent Heart Transplant in Colombia

OBJECTIVES

To evaluate the cost-effectiveness of pharmacological treatment in maintenance therapy for adult heart transplant recipients from the Colombian health system perspective.

METHODS

We constructed a decision tree model with a 1-year time horizon. A review of the clinical literature was performed to extract probabilities of health events and acute rejections avoided were used as the health outcome. Costs were calculated from the base-case approximation and were obtained from administrative databases in Colombia (Sistema de Información de Precios de Medicamentos 2020 and Suficiencia 2012-2019), and the prices were adjusted to US dollar 2021.

RESULTS

Two evaluation results were presented. The first evaluates the tacrolimus + azathioprine + corticosteroid (TAC) scheme compared with cyclosporine + azathioprine + corticosteroid (CAC), in which the incremental cost-effectiveness ratio indicates that 1 additional rejection avoided has a cost of US dollar $5461.09 which, compared with the cost-effectiveness threshold in the base case, indicates that the TAC scheme is not a cost-effective (CE) strategy with respect to the CAC scheme. The second result shows the comparison of tacrolimus + mycophenolate mofetil + corticosteroid (TMC) with cyclosporine + mycophenolate mofetil + corticosteroid (CMC) in which TMC was found to be a dominant alternative to CMC.

CONCLUSIONS

The tacrolimus-based immunosuppression scheme is not CE in its TAC scheme, versus CAC, and is dominant in its TMC scheme, versus CMC, sensitivity analyses show that tacrolimus could become a CE alternative in any scheme used against higher cost-effectiveness threshold.

The risks of rejection vs. infection: Ramsay Hunt syndrome, Gradenigo syndrome, and varicella meningoencephalitis in a heart transplant patient

Background

Orthotopic heart transplant (OHT) recipients are at increased risk for varicella zoster reactivation, and severe complications may arise due to their immunosuppressive regimens. Managing immunosuppression in acute infection is difficult, and specific guideline recommendations or evidence from the literature are lacking. However, patient care must involve weighing the risk of transplant rejection with the consequences of worsening infection.

Case summary

An OHT patient with a history of multiple episodes of acute rejection, latent varicella zoster virus (VZV) infection, and recent completion of anti-viral prophylaxis presented with unilateral facial droop and pain, abducens nerve palsy, crusting facial rash, and ear swelling. Imaging revealed necrotizing otitis externa, with associated otitis media, and petrous apicitis concerning for Gradenigo syndrome. A VZV-positive viral panel confirmed our suspicion for Ramsay Hunt syndrome (RHS). The patient's mentation continued to decline, and subsequent lumbar puncture also revealed VZV meningoencephalitis. The patient's mycophenolate mofetil (MMF) was suspended, with continuation of tacrolimus, and initiation of intravenous acyclovir. The patient demonstrated gradual resolution of his infection, without developing any signs of acute rejection.

Discussion

Varicella zoster virus reactivation is common in OHT patients, particularly when viral prophylaxis is discontinued; however, cardiologists should be aware of the rarer manifestations that can manifest in these immunocompromised patients. This is the first documented case of simultaneous RHS, Gradenigo syndrome, and VZV meningoencephalitis in any patient, regardless of transplant status. We demonstrate that even in patients at very high risk of rejection, MMF can be safely discontinued and host immunity maintained with temporary tacrolimus monotherapy.

Effect of a Fourth Dose of mRNA Vaccine and of Immunosuppression in Preventing SARS-CoV-2 Breakthrough Infections in Heart Transplant Patients

Patients with heart transplantation (HT) have an increased risk of COVID-19 disease and the efficacy of vaccines on antibody induction is lower, even after three or four doses. The aim of our study was to assess the efficacy of four doses on infections and their interplay with immunosuppression. We included in this retrospective study all adult HT patients (12/21–11/22) without prior infection receiving a third or fourth dose of mRNA vaccine. The endpoints were infections and the combined incidence of ICU hospitalizations/death after the last dose (6-month survival rate). Among 268 patients, 62 had an infection, and 27.3% received four doses. Following multivariate analysis, three vs. four doses, mycophenolate (MMF) therapy, and HT < 5 years were associated with an increased risk of infection. MMF ≥ 2000 mg/day independently predicted infection, together with the other variables, and was associated with ICU hospitalization/death. Patients on MMF had lower levels of anti-RBD antibodies, and a positive antibody response after the third dose was associated with a lower probability of infection. In HT patients, a fourth dose of vaccine against SARS-CoV-2 reduces the risk of infection at six months. Mycophenolate, particularly at high doses, reduces the clinical effectiveness of the fourth dose and the antibody response to the vaccine.

Basiliximab as maintenance immunosuppression in heart transplant recipients: A single pediatric center experience

BACKGROUND

Pediatric heart transplant recipients are at risk for complications from prolonged exposure to immunosuppressive drugs, pharmacokinetic challenges in maintaining consistent immunosuppression, and medication non-adherence. Basiliximab (BAS), an interleukin-2 receptor antagonist, is used for induction therapy across many pediatric heart transplant centers, but use as maintenance immunosuppression has not been well described.

METHODS

This was a retrospective, single pediatric center cohort study of heart transplant recipients who received BAS for maintenance immunosuppression (defined as >2 monthly doses) from January 1, 2011, to December 31, 2021.

RESULTS

Ten patients met study criteria with a median age of 17.5 (5-22) years and median 9.6 (1.2-18.9) years since transplant at time of BAS initiation. The primary indications for BAS use were recurrent rejection (n = 4), fluctuating immunosuppression levels (n = 3), and renal dysfunction (n = 3). A median of 5.5 (3-32) monthly BAS doses were received. Three patients had a rejection event while on BAS. Calcineurin inhibitor exposure was reduced in 70% of patients. Three of the 10 patients were alive at last follow-up. There was one documented infection during BAS use, and no hypersensitivity reactions.

CONCLUSIONS

Monthly BAS infusions were well tolerated and allowed for reduced calcineurin inhibitor exposure in most patients. Mortality commonly occurred despite BAS use, potentially reflecting the acuity of this patient cohort. BAS can be considered for maintenance immunosuppression in pediatric patients with fluctuating immunosuppressive levels and/or renal dysfunction. More studies are needed to determine long-term outcomes and explore expanded use of BAS in the pediatric heart transplant population.

Cost-Benefit Analysis of Involving Pharmacist for Medication Therapy Management in a Heart Transplant Clinic

BACKGROUND

Drug-related problems (DRPs) are common in recipients of solid organ transplants. Pharmacist-led medication therapy management (MTM) has cost benefits in kidney and liver transplants; however, whether MTM is also beneficial in heart transplants remains unclear. This study explored the cost benefits of involving pharmacists in the heart transplant clinic.

METHODS

This retrospective study evaluated DRPs for 1 year after implementation of pharmacist-led MTM in a heart transplant clinic. The DRPs were compared between patients receiving transplantation for <1 and >1 year. The risk matrix method was used to assess each DRP in terms of the estimated probability and severity of consequent adverse drug events (ADEs). For cost analysis, both estimated cost savings and avoidance were calculated.

RESULTS

During the 1-year MTM, 372 DRPs were identified by the pharmacist, among which 169 (45%) and 203 (55%) were from patients at <1-year and ≥1-year post-transplant periods, respectively. The 2 post-transplant periods (<1 year and ≥1 year) exhibited significant differences in the distribution of the dosage or frequency problems (30% vs 18%, P = .005) and the suggestion of more appropriate medication (4% vs 10%, P = .024). In all, 92 (29%) DRPs had an ADE probability of >10%; and 63 (17%) DRPs were estimated to cause ADEs with moderate severity or higher. The estimated cost savings and cost avoidance were US $4902 and US $4519, which equaled a cost-benefit ratio of 2.39.

CONCLUSION

Integration of pharmacists into heart transplant clinics could help address DRPs and may have cost benefits.

Achalasia as an Unusual Cause of Acute Cellular Rejection of a Transplanted Heart

A 68-year-old female with end-stage heart failure presented to the hospital for heart transplant. She was diagnosed with achalasia 14 months prior and treated with frequent botulinum toxin injections. She underwent orthotopic heart transplant on the day of admission and was extubated a few days later. She developed intractable nausea and vomiting. Her first endomyocardial biopsy revealed moderate, approaching severe rejection. She was treated with high-dose intravenous pulse steroids. Fluoroscopy at the time of follow-up biopsy showed undigested pills in her esophagus with narrowing at the distal end and thus failure to deliver immunosuppressive therapy. This case highlights achalasia as an etiology for acute rejection and its potential management.

Evolution and current circumstances of heart transplants: Global and Mexican perspective

A cardiac transplant is an irreplaceable alternative for patients with terminal chronic heart failure refractive to treatment. Heart failure results from an imbalance between cardiac output and organic demand, the prominent etiology is ischemic heart disease and arterial hypertension. In developed countries, it has a prevalence of 4.2%, reaching over 11.8% in adults over 65. It affects around 64.3 million people worldwide, with 9 cases for every 1000 people. This syndrome has a death rate of 56% in 5 years, making heart transplants relevant. The procedure has dramatically evolved from the beginning of animal experimentation in the early 20^th century to now, where significant advances are still being made. The purpose of this review is to compile the central aspects of international and Mexico's local heart transplant history and current status, as well as a general view of what this procedure entails and possible prospective outcomes for this practice.

Contemporary review of heart transplant immunology and immunosuppressive therapy

Background

Survival after heart transplantation (HT) has improved considerably since the first HT was performed in 1967 in Cape Town, South Africa. Understanding immunology behind organ rejection has paved way for advances in the assessment of pre-transplant compatibility, development of newer and more specific immunosuppressive drugs, and management of rejection.

Objectives

Unlike medical therapy for heart failure, transplant protocols vary considerably between different centers. These variations in protocols generally reflect unique population characteristics and the availability of resources. This review article aims to provide a consolidated update on contemporary cardiac transplant medicine. We also aim to highlight local practice and its difference from our international counterparts.

Methods

A literature search was performed on Pubmed and Cochrane Central Register of Controlled Trials to identify trials and review articles that discussed heart transplant immunology and protocols. The International Society for Heart and Lung Transplant (ISHLT) guidelines were also reviewed. We focused on risk factors, prevention strategies, and treatment of cardiac rejection.

Results

A total of 48 articles were selected to provide a comprehensive overview of the contemporary practice of cardiac transplant immunosuppressive therapy. Comparisons were made with local data and practice protocols to highlight key differences.

Conclusion

Heart transplant covers a small subset of cardiac patients and much of the evidence is derived from empirical observations and retrospective analysis. This accounts for the heterogeneity in care and treatment protocols. More studies are needed to select best practices from around the world to further improve outcomes.

Heart transplant recipient 1-year outcomes during the COVID-19 pandemic

The COVID‐19 pandemic initially brought forth considerable challenges to the field of heart transplantation. To prevent the spread of the virus and protect immunocompromised recipients, our center made the following modifications to post‐transplant outpatient management: eliminating early coronary angiograms, video visits for postoperative months 7, 9, and 11, and home blood draws for immunosuppression adjustments. To assess if these changes have impacted patient outcomes, the current study examines 1‐year outcomes for patients transplanted during the pandemic. Between March and September 2020, we assessed 50 heart transplant patients transplanted during the pandemic. These patients were compared to patients who were transplanted during the same months between 2011 and 2019 (n = 482). Endpoints included subsequent 1‐year survival, freedom from cardiac allograft vasculopathy, any‐treated rejection, acute cellular rejection, antibody‐mediated rejection, nonfatal major adverse cardiac events (NF‐MACE), and hospital and ICU length of stay. Patients transplanted during the pandemic had similar 1‐year endpoints compared to those of patients transplanted from years prior apart from 1‐year freedom from NF‐MACE which was significantly higher for patients transplanted during the pandemic. Despite necessary changes being made to outpatient management of heart transplant recipients, heart transplantation continues to be safe and effective with similar 1‐year outcomes to years prior.

Prognostic value of patient-reported outcome measures in adult heart-transplant patients: a systematic review

Background

The aim of this systematic review was to describe the prognostic value of patient-reported outcome measures (PROMs) in adult heart-transplant (HT) patients.

Methods

A systematic search was performed on Ovid Medline, CINAHL Plus, Web of Science, and PubMed. The study protocol was registered on the PROSPERO database (CRD42021225398), and the last search was performed on January 7, 2021. We included studies of adult HT patients where generic and disease-specific PROMs were used as prognostic indicators for survival, readmissions, HT complications, and the onset of new comorbidities. We excluded studies that used clinician-reported and patient-experience outcomes. The Quality in Prognosis Studies tool (QUIPS) was used to measure the risk of bias of the included studies.

Results

We included five observational studies between 1987 and 2015, whose populations’ mean age ranged from 43 to 56 years and presented a higher proportion of males than females. The Kansas City Cardiomyopathy Questionnaire demonstrated a negative correlation with readmissions (coefficient = − 1.177, p = 0.031), and the EQ-5D showed a negative correlation with the onset of neuromuscular disease after HT (coefficient = − 0.158, p < 0.001). The Millon Behavioral Health Inventory and the Nottingham Health Profile demonstrated a statistically significant association as survival predictors (p = 0.002 and p < 0.05, respectively). A moderate overall risk of bias was reported in three studies, one study resulted in a low risk of bias, and a proportion of more than 75% of males in each of the studies. High heterogeneity between the studies impeded establishing a link between PROMs and prognostic value.

Conclusion

There is low evidence supporting PROMs usage as prognostic tools in adult HT patients. Comparing outcomes of PROMS to routine prognostic in wider and systematic settings is warranted. Systematic use of PROMs in clinical settings is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41687-022-00431-4.

Association of tacrolimus time-to-therapeutic range on renal dysfunction and acute cellular rejection after orthotopic heart transplantation in a high use basiliximab population

BACKGROUND

Currently, clinicians often delay initiation of tacrolimus after orthotopic heart transplantation (OHT) to help mitigate nephrotoxicity. This study aimed to determine if there is an association between the time-to-therapeutic range (TTT) of tacrolimus, early renal dysfunction, and acute cellular rejection (ACR) after OHT.

METHODS

This was a retrospective, single center study with adult patients who underwent OHT from July 2013 to April 2020. Logistic regression analysis was utilized to examine the association of TTT with new renal dysfunction after tacrolimus initiation post-OHT.

RESULTS

In a study of 317 patients, the unadjusted analysis showed patients who developed new renal dysfunction after tacrolimus initiation had a numerically shorter TTT (9.5 vs. 11.0 days, P = .065), and were more likely to have supratherapeutic tacrolimus levels (56% vs. 39.2%, P = .010). When adjusted for established risk factors for renal dysfunction, TTT was significantly associated with new renal dysfunction (OR .95; 95% CI [.90, .99], P = .03). There was no association between TTT and the incidence of ACR (11.1 vs. 10.8 days, P = .64).

CONCLUSION

When adjusting for known risk factors, a shorter TTT was associated with new renal dysfunction. Supratherapeutic tacrolimus levels were also associated with new renal dysfunction. There was no association between TTT and ACR in the setting of high use basiliximab induction.

Steroid withdrawal after heart transplantation in adults

Corticosteroids (CSs) are a key component of immunosuppressive treatment after heart transplantation (HTx). While effectively preventing acute rejection, several adverse effects including diabetes, hypertension, osteoporosis, and hyperlipidemia are associated with long-term use. As these complications may impair long-term outcome in HTx recipients, withdrawal of CSs is highly desirable, however, no uniform approach exists. Previous experience suggests that CS withdrawal can be accomplished without an increase in the incidence of acute rejection and even carrying a survival benefit. Also, common complications related to long-term CS use appear to be less frequent following CS discontinuation. Recipients who successfully discontinue CSs, however, likely belong to an immune-privileged subset of patients with low risk of post-transplant complications. Available studies evaluating CS withdrawal are highly heterogeneous and consensus on optimal timing and eligibility for withdrawal is lacking. Efforts to improve the understanding of optimal CS withdrawal strategy are of great importance in order to safely promote CS weaning in eligible patients and thereby alleviate the adverse effects of long-term CS use on post-transplant outcomes. The purpose of this review was to evaluate different protocols of CS withdrawal after HTx in terms of clinical outcomes and to explore criteria for successful CS withdrawal.

Impact of induction therapy on outcomes after heart transplantation

BACKGROUND

Approximately 50% of heart transplant (HT) programs utilize induction therapy (IT) with interleukin-2 receptor antagonists (IL2RA) or polyclonal anti-thymocyte antibodies (ATG).

METHODS

Adult HT recipients were identified in the UNOS Registry between 2010 and 2020. We compared mortality between IT strategies with competing risk analysis.

RESULTS

A total of 28 634 HT recipients were included in the study (50.1% no IT, 21.3% ATG, 27.9% IL2RA, .7% alemtuzumab, .01% OKT3). Adjusted all-cause, 30 day and 1 year mortality were lower among those treated with IT than no IT (sub-hazard ratio [SHR] .87, 95% CI .79-.96, SHR .86, .76-.97, SHR .76, .63-.93, P = .007, respectively). In propensity score matching analysis IT was associated with lower 30-day and 1-year mortality. IL2RA had higher all-cause and 1-year mortality than ATG (SHR 1.41, 95% CI 1.23-1.69 and 1.55, 95% CI 1.29-1.88, respectively). Utilization of IT was associated with significantly lower risk of treated rejection at 1 year after HT compared with no IT (relative risk ratio [RRR] .79) and similarly ATG compared with IL2RA (RRR .51).

CONCLUSION

IT was associated with lower mortality and treated rejection episodes than no IT. IL2RA is the most used IT approach but ATG has lower risk of treated rejection and mortality.

Treatment with the calcineurin inhibitor and immunosuppressant cyclosporine A impairs sensorimotor gating in Dark Agouti rats

RATIONALE

Calcineurin is a protein regulating cytokine expression in T lymphocytes and calcineurin inhibitors such as cyclosporine A (CsA) are widely used for immunosuppressive therapy. It also plays a functional role in distinct neuronal processes in the central nervous system. Disturbed information processing as seen in neuropsychiatric disorders is reflected by deficient sensorimotor gating, assessed as prepulse inhibition (PPI) of the acoustic startle response (ASR).

OBJECTIVE

Patients who require treatment with immunosuppressive drugs frequently display neuropsychiatric alterations during treatment with calcineurin inhibitors. Importantly, knockout of calcineurin in the forebrain of mice is associated with cognitive impairments and symptoms of schizophrenia-like psychosis as seen after treatment with stimulants.

METHODS

The present study investigated in rats effects of systemic acute and subchronic administration of CsA on sensorimotor gating. Following a single injection with effective doses of CsA, adult healthy male Dark Agouti rats were tested for PPI. For subchronic treatment, rats were injected daily with the same doses of CsA for 1 week before PPI was assessed. Since calcineurin works as a modulator of the dopamine pathway, activity of the enzyme tyrosine hydroxylase was measured in the prefrontal cortex and striatum after accomplishment of the study.

RESULTS

Acute and subchronic treatment with the calcineurin inhibitor CsA disrupted PPI at a dose of 20 mg/kg. Concomitantly, following acute CsA treatment, tyrosine hydroxylase activity was reduced in the prefrontal cortex, which suggests that dopamine synthesis was downregulated, potentially reflecting a stimulatory impact of CsA on this neurotransmitter system.

CONCLUSIONS

The results support experimental and clinical evidence linking impaired calcineurin signaling in the central nervous system to the pathophysiology of neuropsychiatric symptoms. Moreover, these findings suggest that therapy with calcineurin inhibitors may be a risk factor for developing neurobehavioral alterations as observed after the abuse of psychomotor stimulant drugs.

The experiences of adult heart, lung, and heart-lung transplantation recipients: A systematic review of qualitative research evidence

Aim

To review evidence about the experience of being the recipient of a donated heart, lungs, or heart and lungs.

Design

A systematic review (registered with PROSPERO: CRD42017067218), in accordance with PRISMA guidelines.

Data sources

Seven databases and Google Scholar were searched in May 2017 and July 2019 for papers reporting English-language research that had used qualitative methods to investigate experiences of adult recipients.

Review methods

Quality was assessed and results were analysed thematically.

Results

24 papers (reporting 20 studies) were eligible and included. Their results were organised into three chronological periods: pre-transplant (encompassing the themes of ‘dynamic psychosocial impact’, ‘resources and support’), transplant (‘The Call’, ‘intensive care unit’), and post-transplant (‘dynamic psychosocial impact’, ‘management’, ‘rejection’). Sub-themes were also identified. It was evident that contemplating and accepting listing for transplantation entailed or amplified realisation of the precipitating illness’s existential threat. The period surrounding transplantation surgery was marked by profound, often surreal, experiences. Thereafter, although life usually improved, it incorporated unforeseen challenges. The transplantation clinic remained important to the recipient. The meaning of the clinic and its staff could be both reassuring (providing care and support) and threatening (representing onerous medical requirements and potential organ rejection).

Conclusion

This review has implications for the psychosocial care of transplant recipients and indicates the need for further research to gain insight into the experience of receiving a donated heart and/or lung.

Impact

Medical consequences of heart and lung transplantation are well documented; this is the first systematic review of research using qualitative methods to investigate the experience of heart, lung, and heart-and-lung transplantation. The psychosocial impact of transplantation was found to be dynamic and complex, with notable features evident before, during, and after transplantation. Clinic staff remained significant to recipients. It is clear that recipients need continuing psychosocial as well as medical support.

Prognosis of heart transplant patients in Mashhad University of Medical Sciences

Introduction

Heart transplant is the ultimate treatment for patients with end-stage heart failure.

Aim

To assess 50 heart transplant patients for underlying diseases, transplantation outcome and mortality rate during a 5-year follow-up program.

Material and methods

Fifty heart transplant patients who underwent heart transplantation from 2012 to 2017 were assessed for underlying diseases, organ rejection, duration of hospitalization, extubation time, cardiac output and survival. Biopsy samples were obtained after surgery for evaluation of rejection.

Results

Dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM) were the most common underlying diseases with prevalence of 56% and 12%, respectively. Significant improvement in ejection fraction was observed following heart transplant. Minimum and maximum extubation and hospitalization times were 3–408 hours and 1–51 days, respectively. Organ rejection evaluation 10 days after heart transplantation revealed that 50% of patients did not show any rejection while 10% had severe rejection. At 30 days post-operatively the number of patients with grade III rejection decreased to 2% while 56% of patients had no sign of rejection. The 5-year survival rate was 66% while infection and arrhythmia were the most common causes of death.

Conclusions

DCM and ICM are considered the most prevalent underlying diseases in heart transplant candidates. Ejection fraction reached normal ranges following transplant, which provides good quality of life. Low incidence of severe acute rejection demonstrates the effectiveness of our immunosuppressive therapy. In the cases of increased rejection, the patient’s immunosuppressive regimen was re-assessed accordingly.

Learned Immunosuppressive Placebo Response Attenuates Disease Progression in a Rodent Model of Rheumatoid Arthritis

OBJECTIVE

Patients with chronic inflammatory autoimmune diseases benefit from a broad spectrum of immunosuppressive and antiproliferative medication available today. However, nearly all of these therapeutic compounds have unwanted toxic side effects. Recent knowledge about the neurobiology of placebo responses indicates that associative learning procedures can be utilized for dose reduction in immunopharmacotherapy while simultaneously maintaining treatment efficacy. This study was undertaken to examine whether and to what extent a 75% reduction of pharmacologic medication in combination with learned immunosuppression affects the clinical outcome in a rodent model of type II collagen-induced arthritis.

METHODS

An established protocol of taste-immune conditioning was applied in a disease model of chronic inflammatory autoimmune disease (type II collagen-induced arthritis) in rats, where a novel taste (saccharin; conditioned stimulus [CS]) was paired with an injection of the immunosuppressive drug cyclosporin A (CSA) (unconditioned stimulus [US]). Following conditioning with 3 CS/US pairings (acquisition), the animals were immunized with type II collagen and Freund's incomplete adjuvant. Fourteen days later, at the first occurrence of clinical symptoms, retrieval was started by presenting the CS together with low-dose CSA as reminder cues to prevent the conditioned response from being extinguished.

RESULTS

This "memory-updating" procedure stabilized the learned immune response and significantly suppressed disease progression in immunized rats. Clinical arthritis score and histologic inflammatory symptoms (both P < 0.05) were significantly diminished by learned immunosuppression in combination with low-dose CSA (25% of the full therapeutic dose) via β-adrenoceptor-dependent mechanisms, to the same extent as with full-dose (100%) pharmacologic treatment.

CONCLUSION

These results indicate that learned immunosuppression appears to be mediated via β-adrenoceptors and might be beneficial as a supportive regimen in the treatment of chronic inflammatory autoimmune diseases by diminishing disease exacerbation.

Impact of pretransplant antibodies on outcomes after heart transplantation

Purpose of review

Since the discovery of human leukocyte antigen (HLA) in the 1950s, there has been great interest in the role of antibodies in posttransplant rejection. The development of the lymphocyte toxicity test by Terasaki et al. in the 1960s was the first step toward understanding the role of antibodies in posttransplant rejection.

Recent findings

Subsequently, various organs have been transplanted and improving posttransplant outcomes have become a focus of research. In particular, methods to measure antibodies that affect posttransplant outcomes, including anti-HLA antibodies, and methods to desensitize patients from specific antibodies have been explored. One recent method for measuring antibodies is called the solid-phase assay, which uses purified HLA fixed to microbeads. This assay does not use donor lymphocytes and allows clinicians to test the reactivity of patient serum against a panel of antibodies. It has also enabled the identification of specific anti-HLA antibodies using a single HLA.

Summary

In addition to advances in methods to measure and analyze anti-HLA antibodies, the clinical impact of non-HLA antibodies has also received much attention recently.

Impact of Induction Immunosuppression on Post-Transplant Outcomes of Patients Bridged with Contemporary Left Ventricular Assist Devices

For patients bridged to transplant (BTT) with left ventricular assist devices (LVAD), data regarding the use of induction immunosuppressive therapy remain limited. The objectives of the current study were to describe the current trends and clinical consequences of IT in patients BTT with LVAD. The United Network of Organ Sharing database was queried to identify adult, single-organ heart transplant recipients who were BTT with LVAD between 2008 and 2018. Propensity score matching was then used to balance clinical covariates between those patient who did and did not receive IT. The primary outcomes of interest were graft survival, hospitalization for rejection and infection, and freedom from transplant coronary artery disease (TCAD). In the overall cohort, 49.1% (n = 3,978) received IT, with basiliximab being the most commonly used agent followed by antithymocyte globulin. After propensity score matching, 4,388 patients (2,194 without induction and 2,194 with induction) were identified. Between those who did and did not receive IT, there was no significant difference in graft survival, freedom from hospitalization for rejection, and freedom from hospitalization for infection. Patients who received IT experienced increased freedom from TCAD (p = 0.004) with unadjusted hazard ratio of 0.81 (95% Cardiac Index: 0.70-0.93). For freedom from TCAD, antithymocyte globulin was associated with better outcomes than basiliximab (80.2% vs. 73.1% at 5 years, log rank p value = 0.004). In a sensitivity analysis, there was no significant increase in hospitalization for infection in those patients with an infected LVAD before transplant. Use of induction therapy in patients BTT with LVAD appears to be safe and feasible, without a significant increase in the risk of infection or rejection, even in those patients with pretransplant device-related infections. IT, particularly antithymocyte globulin, was associated with increased time to development of TCAD. Routine use of IT in patients BTT with LVAD may be considered, and further randomized control trials are warranted to further support these data.

Pavlovian Conditioning of Immunological and Neuroendocrine Functions

The phenomenon of behaviorally conditioned immunological and neuroendocrine functions has been investigated for the past 100 yr. The observation that associative learning processes can modify peripheral immune functions was first reported and investigated by Ivan Petrovic Pavlov and his co-workers. Their work later fell into oblivion, also because so little was known about the immune system’s function and even less about the underlying mechanisms of how learning, a central nervous system activity, could affect peripheral immune responses. With the employment of a taste-avoidance paradigm in rats, this phenomenon was rediscovered 45 yr ago as one of the most fascinating examples of the reciprocal functional interaction between behavior, the brain, and peripheral immune functions, and it established psychoneuroimmunology as a new research field. Relying on growing knowledge about efferent and afferent communication pathways between the brain, neuroendocrine system, primary and secondary immune organs, and immunocompetent cells, experimental animal studies demonstrate that cellular and humoral immune and neuroendocrine functions can be modulated via associative learning protocols. These (from the classical perspective) learned immune responses are clinically relevant, since they affect the development and progression of immune-related diseases and, more importantly, are also inducible in humans. The increased knowledge about the neuropsychological machinery steering learning and memory processes together with recent insight into the mechanisms mediating placebo responses provide fascinating perspectives to exploit these learned immune and neuroendocrine responses as supportive therapies, the aim being to reduce the amount of medication required, diminishing unwanted drug side effects while maximizing the therapeutic effect for the patient’s benefit.

Combined Adipose-Derived Mesenchymal Stem Cells and Low-Energy Extracorporeal Shock Wave Therapy Protect the Brain From Brain Death-Induced Injury in Rat

This study tested the hypothesis that combined adipose-derived mesenchymal stem cell (ADMSC) and low-energy extracorporeal shock wave (ECSW) therapy could protect brain from brain death (BD)-induced injury. Adult male Sprague Dawley rats were categorized into group 1 (sham control), group 2 (BD), group 3 (BD + ECSW [0.15 mJ/mm2/300 impulses] applied to the skull surface 3 hours after BD induction), group 4 (BD + ADMSC [1.2 × 106 cell] by intravenous injection 3 hours after BD induction) and group 5 (BD + ECSW + ADMSC). By 6 hours after BD induction, circulating/spleen levels of immune cells (CD3/CD4+, CD8/CD4+, Treg+) and circulating levels of inflammatory cells (MPO/Ly6G/CD11a/b) and soluble mediators (TNF-α/IL-6) were lowest in group 1 and significantly progressively reduced from groups 2 to 5 (all p < 0.0001). Brain protein expressions of inflammatory (TNF-α/NF-κB/MMP-9/IL-1β), apoptotic (caspase-3/PARP/mitochondrial-BAX), oxidative stress/DNA-damage (NOX-1/NOX-2/oxidized protein/γ-H2AX) biomarkers exhibited an identical pattern, whereas anti-oxidant (SIRT1/SIRT3) and mitochondrial-integrity (mitochondrial-cytochrome-C) biomarkers exhibited an opposite pattern to inflammatory biomarkers among the 5 groups (all p < 0.0001). The cellular expressions of inflammatory/brain-edema (F4/80/CD14+/GFAP/AQP4) biomarkers exhibited an identical pattern to inflammation among the 5 groups (all p < 0.0001). In conclusion, ECSW-ADMSC therapy is superior to either alone for attenuating brain from BD-induced damage.

Association between aortic telomere length and cardiac post-transplant allograft function

BACKGROUND

In patients having undergone orthotopic heart transplantation, a number of complications exist that are known to be connected to both telomerase activity and telomere length. The aim of this study was to determine how telomere length in aortic DNA correlates with the subsequent post-transplantation development of the patients.

MATERIALS AND METHODS

Between 2005 and 2015, we collected aortic samples from 376 heart recipients (age 50.8 ± 11.8 years) and 383 donors (age 38.6 ± 12.2 years). Relative telomere length in aortic tissue DNA was determined using quantitative PCR.

RESULTS

Shorter telomere length was detected in heart allograft recipients compared to donors (P < 0.0001). Patients suffering acute cellular rejection had significantly shorter telomere length (P < 0.01) than patients without rejection. Shorter telomere length was observed in patients with implanted mechanical circulatory support before heart transplantation (P < 0.03), as well as in subjects with cardiac allograft vasculopathy (P < 0.05). Overall survival time after heart transplantation was associated with shorter donor telomeres (P < 0.004).

CONCLUSIONS

Telomere length differed between donors and recipients independent of the sex and age of the patients. Our findings suggest a potential new linkage between the aortic telomere length of recipients and post-heart transplant complications. Further studies focusing on epigenetic modifications and gene regulation involved in telomere maintenance in transplanted patients should verify our results.

Risk of new-onset atrial fibrillation among heart, kidney and liver transplant recipients: insights from a national cohort study

The objective of the study was to explore the incidence of atrial fibrillation (AF) in various populations of patients with organ transplantation (OT). We used a large national data set from Taiwan to investigate the incidence of AF after OT. Frequency matching method used to match controls: OT patients were 4:1. Kaplan-Meier analyses with the use of the Aalen-Johansen estimator was employed for estimating the cumulative incidences of new-onset AF. The Fine-Gray competing risks model was also employed to analyze the risk of AF for the OT cohort compared with the non-OT cohort. 6955 OT patients and 27,820 controls were included in this study. OT did lead to a 3.09-fold risk for AF [95% confidence interval (CI) = 2.07-4.62], especially in the subgroup of female gender [adjusted subhazard ratio (aSHR) = 6.66, 95% CI = 3.85-11.5], age ≤ 49 years (aSHR = 8.19, 95% CI = 3.99-16.8) and without comorbidity (aSHR = 4.61, 95% CI = 2.71-7.87). Moreover, liver recipients tended to be more likely to develop new-onset AF among those OT patients (aSHR = 4.07, 95% CI = 2.63-6.30) as compared to the controls. This study demonstrates an increased incidence of AF after OT. Heightened awareness and clinician vigilance are warranted to facilitate early diagnosis and improved outcomes.

Life-Saving Combined Heart-Kidney Transplantation in a Previous Sequential Heart and Kidney Transplant Recipient

Purpose

Solid organ re-transplantation in the context of allograft failure is a challenging clinical and ethical problem. Ideally, solid organ re-transplantation after initial allograft failure should be performed in all recipients, but this is often not clinically or logistically feasible.

Methods

This report details what we believe is the first combined heart–kidney transplant in a recipient of a previous sequential heart and kidney transplant.

Results

Eight years after a combined heart and kidney transplant after initially receiving a sequential heart and kidney transplant, a 31-year-old man is doing extremely well, with no rejection episodes or significant complications after transplantation.

Summary

This case confirms that combined heart and kidney transplantation is a viable option for tackling the complex issue of graft failure in recipients of previous cardiac and renal grafts.

LEARNING POINTS

Increase in short-term risk of rejection in heart transplant patients receiving granulocyte colony-stimulating factor

BACKGROUND

Neutropenia is a significant adverse event after heart transplantation (HT) and increases infection risk. Granulocyte colony-stimulating factor (G-CSF) is commonly used in patients with neutropenia. In this work, we assessed the adverse effects of G-CSF treatment in the setting of a university hospital.

METHODS

Data on HT patients from January 2008 to July 2016 were reviewed. Patients who received G-CSF were identified and compared with patients without a history of therapy. Baseline characteristics, rejection episodes, and outcomes were collected. Data were analyzed by incidence rates, time to rejection and survival were analyzed using Kaplan-Meier curves, and odds ratios were generated using logistic regression analysis.

RESULTS

Two hundred twenty-two HT patients were studied and 40 (18%) received G-CSF for a total of 85 total neutropenic events (0.79 event/patient year). There were no differences in baseline characteristics between the groups. In the 3 months after G-CSF, the incidence rate of rejection was 0.067 event/month. In all other time periods considered free of G-CSF effect, the incidence rate was 0.011 event/month. This rate was similar to the overall incidence rate in the non-GCSF group, which was 0.010 event/month. There was a significant difference between the incidence rates in the G-CSF group at 0 to 3 months after G-CSF administration and the non-GCSF group (p = 0.04), but not for the other time periods (p = 0.5). Freedom from rejection in the 3 months after G-CSF administration was 87.5% compared with 97.5% in the non-GCSF group (p = 0.006).

CONCLUSIONS

G-CSF administration was found to be associated with significant short-term risk of rejection. This suggests the need for increased surveillance during this time period.

Melatonin attenuated brain death tissue extract-induced cardiac damage by suppressing DAMP signaling

We tested the hypothesis that melatonin prevents brain death (BD) tissue extract (BDEX)-induced cardiac damage by suppressing inflammatory damage-associated molecular pattern (DAMP) signaling in rats. Six hours after BD induction, levels of a DAMP component (HMGB1) and inflammatory markers (TLR-2, TLR-4, MYD88, IκB, NF-κB, IL-1β, IFN-γ, TNF-α and IL-6) were higher in brain tissue from BD animals than controls. Levels of HMGB1 and inflammatory markers were higher in BDEX-treated H9C2 cardiac myoblasts than in cells treated with healthy brain tissue extract. These increases were attenuated by melatonin but re-induced with luzindole (all P < 0.001). Additional male rats (n = 30) were divided into groups 1 (negative control), 2 (healthy brain tissue extract implanted in the left ventricular myocardium [LVM]), 3 (BDEX-LVM), 4 (BDEX-LVM + melatonin), and 5 (BDEX-LVM + melatonin + luzindole). Collagen deposition/fibrosis and LVM levels of MTR2, HMGB1, inflammatory markers, oxidative stress, apoptosis, mitochondrial damage and DNA damage were highest in group 3, lowest in groups 1 and 2, and higher in group 5 than in group 4. Heart function and LVM levels of MTR1 and anti-inflammatory, mitochondrial-integrity and anti-oxidative markers exhibited a pattern opposite that of the inflammatory markers in the five groups (all P < 0.0001). These results indicate melatonin inhibits BDEX-induced cardiac damage by suppressing the DAMP inflammatory axis.

Change in lymphocyte to neutrophil ratio predicts acute rejection after heart transplantation

AIMS

Most immunosuppressive drugs provide targeted immunosuppression by selective inhibition of lymphocyte activation and proliferation. This study evaluated whether a change in the lymphocyte to neutrophil ratio (LNR) is related to acute rejection.

METHODS

In 74 cardiac transplant recipients peripheral blood lymphocyte and neutrophil counts were measured soon after (baseline) and three, six, and 12months after heart transplantation. The primary endpoint was the incidence of acute rejection.

RESULTS

Significant acute rejection after heart transplantation occurred in 20 patients (27%) during a median follow-up of 49.4 [IQR 37.4-61.1] months. LNR significantly increased over time (0.1149±0.1354 at baseline, 0.2330±0.2266 at 3months, 0.2961±0.2849 at 6months, and 0.3521±0.2383 at 12months; P<0.001), especially during the first 3months in the group without acute rejection. The area under the curve of the change in LNR during the first three months (ΔLNR) for acute rejection was 0.565 (95% CI 0.420 to 0.710, P=0.380) on ROC curve analysis. The best cutoff value of Δ LNR to differentiate those with and without acute rejection was ≤0.046 by ROC curve analysis. Kaplan-Meier analysis revealed that the low ΔLNR group (≤0.046) had a significantly higher rate of acute rejection than the high ΔLNR group (>0.046) (37.5% vs. 19.0%, log-rank: P=0.0358). The low ΔLNR for the first 3months was an independent predictor of clinically significant acute rejection after adjusting for cytomegalovirus donor seropositive and recipient seronegative.

CONCLUSIONS

The results of this study suggest that ΔLNR over the first 3months after heart transplantation is a strong and independent predictor of acute rejection after heart transplantation. ΔLNR can be used as an early biomarker for predicting of acute rejection after heart transplantation.

Exosomal miR-142-3p is increased during cardiac allograft rejection and augments vascular permeability through down-regulation of endothelial RAB11FIP2 expression

Aims

Exosome-mediated microRNA transfer is a recently discovered mode of cell-to-cell communication, in which microRNAs act as paracrine molecules, exerting their regulatory effects in recipient cells. T cells and endothelial cells are two main players in the mechanism of acute cellular cardiac rejection. The aim of this study was to investigate the role of exosomal microRNAs in the crosstalk between T cells and endothelial cells and its implications for the molecular mechanisms that drive acute cellular rejection in heart transplantation.

Methods and results

Exosomes isolated from serum samples of heart transplant patients with and without acute cardiac allograft rejection were profiled and showed enrichment of miR-142-3p, miR-92a-3p, miR-339-3p and miR-21-5p. Treatment of endothelial cells with the respected serum exosomes resulted the increased of miR-142-3p level in endothelial cells. Using T cells isolated from healthy donors and activated with either anti-CD3/CD28 antibody or IL-2/PHA, we could show that miR-142-3p is released from activated cells, is contained in exosomes and can be transferred to human vascular endothelial cells in vitro. Transcriptome analysis of endothelial cells treated with activated T cell supernatant with or without exosomes was used to identify mRNA targets of transferred miR-142-3-p. Overexpression of miR-142-3p in endothelial cells resulted in a significant down-regulation of RAB11FIP2, and interaction of miR-142-3p with its predicted target site was confirmed with a reporter assay. Moreover, treatment of endothelial cells with serum exosomes from heart transplant patients with acute cellular rejection resulted in down-regulation of RAB11FIP2 expression and increase in vascular endothelial permeability.

Conclusion

We have identified a novel mechanism whereby miR-142-3p, a microRNA enriched in exosomes during acute cellular rejection, is transferred to endothelial cells and compromises endothelial barrier function via down-regulation of RAB11FIP2. This study sheds new light on the interaction between host immune system and cardiac allograft endothelium during acute cellular rejection.

Therapeutic effects of adipose-derived mesenchymal stem cells against brain death-induced remote organ damage and post-heart transplant acute rejection

We tested the hypothesis that allogenic adipose-derived mesenchymal stem cells (ADMSCs) alleviated brain death (BD)-induced remote organ damage and events of post heart-transplant acute rejection. To determine the impact of BD on remote organ damage, adult-male F344 rats (n=24) were categorized sham-control (SC), BD and BD^MSC (allogenic ADMSC/1.2 × 10⁶ cells/derived from F344 by intravenous transfusion 3 h after BD procedure). To determine the protective effect of allogenic ADMSCs, animals (n=8/each group in F344/Lewis) were categorized into groups BD-T(F344 heart transplanted into Lewis by 6h after BD), BD-T^MSC(D1/3) (BD induction for 6h then heart transplantation, and allogenic ADMSCs transfusion at days 1 and 5 after heart transplantation), BD-T^MSC(3h) (BD + ADMSC/1.2 × 10⁶ cells at 3h and heart transplantation at 6h after BD) and BD-T^{MSC(3h, D1/3)} [BD + ADMSC/1.2 × 10⁶ cells at 3h and heart transplantation at 6h after BD, then ADMSC therapy by days 1/3]. At day 5 post procedure, liver, kidney and heart specimens showed higher molecular-cellular levels of inflammation, immune reaction, apoptosis and fibrosis in BD than in SC that were reversed in BD^MSC (all P < 0.0001). These molecular-cellular expressions and circulating/splenic levels of innate/adoptive immune cells were higher in BD-T, lowest in BD-T^{MSC(3h, D1/3)} and higher BD-T^MSC(3h) in than BD-T^MSC(D1/3), whereas heart function showed an opposite pattern among the four groups (all P < 0.001). In conclusion, ADMSCs suppressed BD-caused remote organ damage and heart-transplant rejection.

Thalidomide treatment prevents chronic graft rejection after aortic transplantation in rats - an experimental study

Cardiac allograft vasculopathy (CAV) affects approximately 30% of cardiac transplant patients at 5 years post-transplantation. To date, there are few CAV treatment or prevention options, none of which are highly effective. The aim of the study was to investigate the effect of thalidomide on the development of CAV. The effect of thalidomide treatment on chronic rejection was assessed in rat orthotopic aortic transplants in allogeneic F344 or syngeneic Lew rats (n = 6 per group). Animals were left untreated or received thalidomide for 30 days post-transplant, and evidence of graft CAV was determined by histology (trichrome and immunohistochemistry) and intragraft cytokine measurements. Animals that received thalidomide treatment post-transplant showed markedly reduced luminal obliteration, with concomitant rescue of smooth muscle cells (SMCs) in the aortic media of grafts. Thalidomide counteracted neointimal hyperplasia by preventing dedifferentiation of vascular SMCs. Measurement of intragraft cytokine levels after thalidomide treatment revealed downregulation of matrix metalloproteinase 8 and monocyte chemotactic protein 1, cytokines involved in tissue remodelling and inflammation, respectively. Importantly, no negative side effects of thalidomide were observed. Thalidomide treatment prevents CAV development in a rodent model and is therefore potentially useful in clinical applications to prevent post-transplant heart rejection.

Testing the Efficacy of Contrast-Enhanced Ultrasound in Detecting Transplant Rejection Using a Murine Model of Heart Transplantation

One of the key unmet needs to improve long-term outcomes of heart transplantation is to develop accurate, noninvasive, and practical diagnostic tools to detect transplant rejection. Early intragraft inflammation and endothelial cell injuries occur prior to advanced transplant rejection. We developed a novel diagnostic imaging platform to detect early declines in microvascular perfusion (MP) of cardiac transplants using contrast-enhanced ultrasonography (CEUS). The efficacy of CEUS in detecting transplant rejection was tested in a murine model of heart transplants, a standard preclinical model of solid organ transplant. As compared to the syngeneic groups, a progressive decline in MP was demonstrated in the allografts undergoing acute transplant rejection (40%, 64%, and 92% on days 4, 6, and 8 posttransplantation, respectively) and chronic rejection (33%, 33%, and 92% on days 5, 14, and 30 posttransplantation, respectively). Our perfusion studies showed restoration of MP following antirejection therapy, highlighting its potential to help monitor efficacy of antirejection therapy. Our data suggest that early endothelial cell injury and platelet aggregation contributed to the early MP decline observed in the allografts. High-resolution MP mapping may allow for noninvasive detection of heart transplant rejection. The data presented have the potential to help in the development of next-generation imaging approaches to diagnose transplant rejection.

Postoperative management of heart transplantation patients

Heart transplant recipients are at risk for a number of post-transplantation complications such as graft dysfunction, rejection, and infection. The rates of many complications are decreasing over time, and prognosis is improving. However, these patients continue to experience significant morbidity and mortality. This review focuses on the optimal management of heart transplant recipients in the postoperative period, based on current knowledge. More information is needed about the best ways to predict, prevent, and treat primary graft dysfunction, right ventricular failure, and cellular and antibody-mediated rejection.

Perioperative Management of Cardiac Transplant Recipients Undergoing Noncardiac Surgery: Unique Challenges Created by Advancements in Care

Advancements in postcardiac transplant care have resulted in significant reductions in morbidity and increased life expectancy for cardiac transplant recipients. Consequently, many cardiac transplant recipients are living long enough to require subsequent noncardiac surgery. The perioperative care of heart transplant recipients presents a unique challenge as many of the common preoperative risk assessments do not apply to a transplanted heart, immunosuppressive medications have side effects and potential for drug-drug interactions, and the denervated heart results in an altered autonomic physiology and response to medications. Further adding to the challenge is that many of these noncardiac surgeries need to be performed urgently at nontransplant centers that may not be familiar with the care of these patients. This review aims to summarize the current data regarding preoperative assessment, perioperative immunosuppression management, intraoperative and anesthetic considerations, and outcomes of cardiac transplant recipients undergoing noncardiac surgery.

Use of Anti-Thymocyte Globulin for Induction Therapy in Cardiac Transplantation: A Review

The most common causes of death after heart transplantation (HTx) include acute rejection and multi-organ failure in the early period and malignancy and cardiac allograft vasculopathy (CAV) in the late period. Polyclonal antibody preparations such as rabbit anti-thymocyte globulin (ATG) may reduce early acute rejection and the later occurrence of CAV after HTx. ATG therapy depletes T cells, modulates adhesion and cell-signaling molecules, interferes with dendritic cell function, and induces B-cell apoptosis and regulatory and natural killer T-cell expansion. Evidence from animal studies and from retrospective clinical studies in humans indicates that ATG can be used to delay calcineurin inhibitor (CNI) exposure after HTx, thus benefiting renal function, and to reduce the incidence of CAV and ischemia-reperfusion injury in the transplanted heart. ATG may reduce de novo antibody production after HTx. ATG does not appear to increase cytomegalovirus infection rates with longer prophylaxis (6-12 months). In addition, ATG may reduce the risk of lymphoproliferative disease and does not appear to confer an additive effect on acquiring lymphoma after HTx. Randomized, controlled trials may provide stronger evidence of ATG association with patient survival, graft rejection, renal protection through delayed CNI initiation, as well as other benefits. It can also help establish optimal dosing and patient criteria to maximize treatment benefits.

CD16+ Monocytes and Skewed Macrophage Polarization toward M2 Type Hallmark Heart Transplant Acute Cellular Rejection

Background

During acute heart transplant rejection, infiltration of lymphocytes and monocytes is followed by endothelial injury and eventually myocardial fibrosis. To date, no information is available on monocyte–macrophage-related cellular shifts and their polarization status during rejection. Here, we aimed to define and correlate monocyte–macrophage endomyocardial tissue profiles obtained at rejection and time points prior to rejection, with corresponding serial blood samples in 25 heart transplant recipients experiencing acute cellular rejection. Additionally, 33 healthy individuals served as control.

Materials and methods

Using histology, immunohistochemistry, confocal laser scan microscopy, and digital imaging expression of CD14, CD16, CD56, CD68, CD80, and CD163 were explored to define monocyte and macrophage tissue profiles during rejection. Fibrosis was investigated using Sirius Red stainings of rejection, non-rejection, and 1-year biopsies. Expression of co-stimulatory and migration-related molecules on circulating monocytes, and production potential for pro- and anti-inflammatory cytokines were studied using flow cytometry.

Results

At tissue level, striking CD16+ monocyte infiltration was observed during rejection (p < 0.001). Significantly more CD68+CD163+ M2 macrophages were documented during rejection compared to barely present CD68+CD80+ M1 macrophages. Rejection was associated with severe fibrosis in 1-year biopsies (p < 0.001). Irrespective of rejection status, decreased frequencies of circulating CD16+ monocytes were found in patients compared to healthy individuals. Rejection was reflected by significantly increased CD54 and HLA-DR expression on CD16+ monocytes with retained cytokine production potential.

Conclusion

CD16+ monocytes and M2 macrophages hallmark the correlates of heart transplant acute cellular rejection on tissue level and seem to be associated with fibrosis in the long term.

Clopidogrel-Precipitated Rhabdomyolysis in a Stable Heart Transplant Patient

Objective:

To report the case of an orthotopic heart transplant recipient who developed rhabdomyolysis precipitated by the addition of clopidogrel to the existing regimen of cyclosporine and atorvastatin, which had been tolerated for more than 3 years without adverse effects or laboratory evidence of myositis.

Case Summary:

Fourteen years after cardiac transplantation, a 58-year-old woman began a planned 4 week course of clopidogrel 75 mg/day following coronary angioplasty and placement of a stent in the left circumflex coronary artery. Almost 4 weeks later, she presented with severe muscle pain and weakness and laboratory evidence of rhabdomyolysis, with marked elevations of plasma creatine kinase (96 000 U/L) and urine myoglobin (332 872 μg/L.) as well as early acute renal failure (serum creatinine 2.9 mg/dL). Symptoms and laboratory abnormalities resolved with cessation of cyclosporine, atorvastatin, and clopidogrel. Clopidogrel was not restarted, while atorvastatin and cyclosporine were; the patient had no recurrence of symptoms up to 15 months later.

Discussion:

Both atorvastatin and cyclosporine, as well as clopidogrel's active thiol derivative, are metabolized by the cytochrome P450 3A4 isoenzyme. Cyclosporine is also a moderate inhibitor of this isoenzyme. We postulate that competition between atorvastatin and clopidogrel for CYP3A4 receptors, already partially inhibited by cyclosporine, led to increased atorvastatin concentrations, resulting in the acute onset of rhabdomyolysis. This theory is further supported by the patient's continued ability to tolerate the combination of atorvastatin and cyclosporine, without clopidogrel, on rechallenge. Use of the Naranjo probability scale revealed that rhabdomyolysis was probably precipitated by the addition of clopidogrel to the stable baseline regimen of cyclosporine and atorvastatin.

Conclusions:

Practitioners must be conscious of the potential for adverse effects when prescribing clopidogrel to heart transplant patients who are concomitantly receiving cyclosporine and a statin. If concomitant administration is required, careful clinical and laboratory monitoring of the patient is necessary.

Heart Transplantation-The Pediatric Cardiac Critical Care Perspective

OBJECTIVES

Although there have been tremendous advancements in the care of severe pediatric cardiovascular disease, heart transplantation remains the standard therapy for end-stage heart disease in children. As such, these patients comprise an important and often complex subset of patients in the ICU. The purpose of this article is to review the causes and management of allograft dysfunction and the medications used in the transplant population.

DATA SOURCES

MEDLINE, PubMed, and Cochrane Database of systemic reviews.

CONCLUSIONS

Pediatric heart transplant recipients represent a complex group of patients that frequently require critical care. Their immunosuppressive medications, while being vital to maintenance of allograft function, are associated with significant short- and long-term complications. Graft dysfunction can occur from a variety of etiologies at different times following transplantation and remains a major limitation to long-term posttransplant survival.

Skeletal Myoblast Cell Sheet Implantation Ameliorates Both Systolic and Diastolic Cardiac Performance in Canine Dilated Cardiomyopathy Model

Background

Improving both systolic and diastolic function may be the most important factor in treating heart failure. In this study, we hypothesized that cell-sheet transplantation could improve these function in the damaged heart.

Methods

We generated a dilated cardiomyopathy model in beagles by continuous ventricle pacing at 240 beats per minute. After 4 weeks, the beagles underwent skeletal myoblast cell sheet transplantation (SMCST) or a sham operation, and rapid ventricle pacing continued for an additional 4 weeks. Six of the e8 beagles treated by SMCST were still alive 4 weeks after the procedure. We evaluated SMCST's cardiotherapeutic effects by comparing beagles treated by SMCST with beagles that underwent a sham operation (control, n = 5).

Results

Diastolic function, as well as systolic function improved significantly in the SMCST group as compared with the sham group (control vs SMCST group, median [interquartile range]: E/E', 16 [0.9] vs 11 [1.0]; P < 0.001; tau, 47 [6.0] vs 36 [4.4] ms: P = 0.005. Ejection fraction, 22 (6.0) versus 46 (7.5) %, P < 0.001; end-systolic elastance, 2.5 (0.4) versus 8.2 (3.5) mm Hg/ml, P = 0.001). Histological examination revealed that the volume of collagen I and the collagen I/III ratio in the myocardium were significantly higher in the control than that in the SMCST group (collagen I, 6.0 [0.8] vs 2.6 [1.3]; P = 0.006; collagen I/III ratio, 4.8 [1.7] vs 1.2 [0.4]; P = 0.010).

Conclusions

The potential of SMCST to ameliorate both systolic and diastolic performance was proven. The SMCST may be an alternative therapy of conventional medical treatment in the dilated cardiomyopathy heart.

Low Incidence of Malignancy After Heart Transplantation in Taiwan

BACKGROUND

Malignancy is the leading cause of death in Taiwan. The risk of malignancy is higher in heart transplant recipients than in the general population. We reviewed the malignancy incidence among the patients who underwent heart transplantation (HT) at the National Taiwan University Hospital (NTUH) during the past 28 years. We found that the incidence of malignancy is low in Taiwan and that the pattern of malignancy is different from that in the Western population.

METHODS

From July 1987 to March 2015, 518 patients underwent HT at NTUH. Forty-four patients who died within 1 month after transplantation were excluded from this study. Thus, a total of 476 patients were enrolled in this study. There were 393 male and 83 female patients, with a mean age of 45 years at transplantation. The major indications for HT were dilated cardiomyopathy (52%) and ischemic cardiomyopathy (33%). After HT, all patients received triple immunosuppressive therapy, including a calcineurin inhibitor (cyclosporine or tacrolimus), cell-cycle inhibitor (azathioprine, mycophenolate mofetil, or everolimus), and steroid. After 1995, induction with rabbit anti-human thymocyte globulin was routinely performed. Survival was estimated by means of the Kaplan-Meier method.

RESULTS

Twenty-seven patients without pre-transplantation malignancy developed malignancies after HT. The median survival time (MST) of these 27 HT patients was 76.8 months. After malignancy was diagnosed, the overall MST was 20.7 months. The 3- and 5-year overall survival rates were 44% and 27%, respectively. Twenty-one patients (77.8%) died, 10 of them because of cancer. The most common malignancy was non-Hodgkin lymphoma (n = 6), followed by skin cancer (including 2 keratoacanthomas, 2 squamous cell carcinomas, and 1 basal cell carcinoma; n = 5) and lung squamous cell carcinoma (n = 3). The univariate analysis identified cancer stage (P = .044) and comorbidity (P = .002) as factors associated with poor malignancy survival. In the multivariate analysis, comorbidity was an independent prognostic factor for greater risk of death because of post-transplantation malignancy (P = .002).

CONCLUSIONS

In Taiwan, the risk of malignancy after HT is low (5.7%), as is the incidence of skin cancer. The most common malignancy was non-Hodgkin lymphoma, followed by skin cancer and lung cancer. Comorbidity was an independent factor for overall survival in cancer patients who previously underwent HT.

Ribonuclease (RNase) Prolongs Survival of Grafts in Experimental Heart Transplantation

BACKGROUND

Cell damage, tissue and vascular injury are associated with the exposure and release of intracellular components such as RNA, which promote inflammatory reactions and thrombosis. Based on the counteracting anti-inflammatory and cardioprotective functions of ribonuclease A (RNase A) in this context, its role in an experimental model of heart transplantation in rats was studied.

METHODS AND RESULTS

Inbred BN/OrlRj rat cardiac allografts were heterotopically transplanted into inbred LEW/OrlRj rats. Recipients were intravenously treated every other day with saline or bovine pancreatic RNase A (50 μg/kg). Toxic side effects were not found (macroscopically and histologically). Heart tissue flow cytometry and quantitative morphological analyses of explanted hearts at postoperative day 1 or postoperative day 4 showed reduced leukocyte infiltration, edema, and thrombus formation in RNase A-treated rats. In allogeneic mixed lymphocyte reactions, RNase A decreased the proliferation of effector T cells. RNase A treatment of rats resulted in prolonged median graft survival up to 10.5 days (interquartile range 1.8) compared to 6.5 days (interquartile range 1.0) in saline treatment (P=0.001). Treatment of rats with a new generated (recombinant) human pancreatic RNase 1 prolonged median graft survival similarly, unlike treatment with (recombinant) inactive human RNase 1 (each 50 μg/kg IV every other day, 11.0 days, interquartile range 0.3, versus 8.0 days, interquartile range 0.5, P=0.007).

CONCLUSIONS

Upon heart transplantation, RNase administration appears to present a promising and safe drug to counteract ischemia/reperfusion injury and graft rejection. Furthermore, RNase treatment may be considered in situations of critical reperfusion after percutaneous coronary interventions or in cardiac surgery using the heart-lung machine.

Cardiac Transplantation in the New Era

The prevalence of heart failure continues to rise due to the aging population and longer survival of people with conditions that lead to heart failure, eg, hypertension, diabetes, and coronary artery disease. Although medical therapy has had an important impact on survival of patients and improving quality of life, heart transplantation remains the definitive therapy for patients that eventually deteriorate. Since the first successful heart transplantation in 1967, significant improvements have been made regarding donor and recipient selection, surgical techniques, and postoperative care. However, the number of potential organ donors has not changed and the growing number of patients in need for transplantation has resulted an increase in waiting list time, and the need for mechanical support. To overcome this issue, the United Network for Organ Sharing implemented an allocation system to prioritize the sickest patients on the list to receive organs. Despite the careful selection of patients, pretransplant immunological screening, and multidrug immunosuppressive regimens, acute and chronic rejections occur and potentially limit graft and patient survival. Treatment for rejection largely depends on the type of rejection, the presence of hemodynamic compromise, and time after transplantation. The limiting factor for long-term graft survival is allograft vasculopathy, an immune-mediated process causing diffuse narrowing of the coronary arteries. Percutaneous coronary intervention and coronary artery bypass surgery are often not an option for this vasculopathy due to the lack of focal lesions, and retransplantation is the only option in appropriate patients.