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Background: Although acute cellular rejection after heart transplantation (HTX) can be controlled by full-dose calcineurin inhibitor (CNI)-based immunosuppressive regimens, cardiac allograft vasculopathy (CAV), nephrotoxicity, and malignancy remain ongoing problems. To evaluate the potential beneficial effects of sirolimus and CNI reduction, we compared de novo low-dose tacrolimus and sirolimus with standard tacrolimus and mycophenolate mofetil (MMF)-based immunosuppression after HTX., Methods: We analyzed a long-term follow-up cohort of 126 patients who underwent HTX during the period 1998-2005 and received either de novo low-dose tacrolimus/sirolimus (lowTAC/SIR; n = 61) or full-dose tacrolimus/MMF (TAC/MMF; n = 64)., Results: Freedom from treatment switch was less in the low TAC/SIR group than in the TAC/MMF group (51.7% vs 73.0%, p = 0.038) 8 years after HTX. Freedom from acute rejection was 90.6% in the low TAC/SIR group vs 80.3% in the TAC/MMF group (p = 0.100). There was no difference in freedom from International Society for Heart and Lung Transplantation CAV grade ≥ 1 (55.4% vs 60.0%, p = 0.922), time until CAV diagnosis (4.2 ± 2.0 years vs 3.2 ± 2.4 years, p = 0.087), and CAV severity (p = 0.618). The benefit of reduced early maximum creatinine for low TAC/SIR treatment (1.8 ± 0.9 mg/dl vs 2.4 ± 1.1 mg/dl in TAC/MMF group, p < 0.001) did not continue 5 years and 8 years after HTX (1.4 ± 0.4 mg/dl vs 1.7 ± 1.2 mg/dl, p = 0.333, and 1.6 ± 1.1 mg/dl vs 1.6 ± 0.8 mg/dl, p = 0.957). The trend for superior survival at 5 years with low TAC/SIR treatment (93.1% vs 81.3% in TAC/MMF group, p = 0.051) could not be confirmed after 8 years (84.7% vs 75.0%, p = 0.138). Multivariate analysis at 8 years did not reveal any benefit of low TAC/SIR treatment., Conclusions: Reduction of de novo CNI did not result in superior long-term renal function. Low-dose mechanistic target of rapamycin inhibition did not achieve any benefit in CAV prevention compared with full-dose TAC/MMF after HTX., (Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Objectives: Calcineurin inhibitor-induced nephrotoxicity reduces long-term patient survival after heart transplant. Proliferation signal inhibitors, in combination with or replacing calcineurin inhibitors, may preserve or improve renal function. We evaluated the effect of calcineurin inhibitor-reduction and withdrawal in everolimus-based immunosuppression on renal function after a heart transplant., Materials and Methods: Twenty-four patients with creatinine clearance < 1 mL/s (60 mL/min) were switched from tacrolimus and mycophenolate mofetil to low-dose tacrolimus/everolimus if their heart transplant was ≤ 1 year ago (group 1, n=13) and to everolimus/mycophenolate mofetil if their heart transplant was > 1 year ago (group 2, n=11). Serum creatinine levels and calculated creatinine clearance were analyzed up to 12 months after conversion., Results: The switch in immunosuppression was associated with a significant decrease/increase of serum creatinine/creatinine clearance in both groups between baseline and month 12 (group 1, creatinine, 221.0 ± 70.7 to 159.1 ± 44.2 μmol/L (2.5 ± 0.8 to 1.8 ± 0.5 mg/dL); creatinine clearance, 0.75 ± 0.45 to 1.01 ± 0.50 mL/s (45.1 ± 26.7 to 60.5 ± 29.7 mL/min) (P < .01 each); group 2, creatinine, 247.5 ± 79.6 to 159.1 ± 44.2 μmol/L (2.8 ± 0.9 to 1.8 ± 0.5 mg/dL), creatinine clearance, 0.57 ± 0.23 to 0.93 ± 0.33 mL/s (34.1 ± 13.8 to 55.7 ± 19.6 mL/min) [P < .05 each]) with no significant group difference in the creatinine and the creatinine clearance levels after switching. No acute rejections or deaths occurred during the 12-month follow-up. Four patients (36.4%) from group 2 and 1 patient (7.7%) from group 1 discontinued everolimus because of adverse events., Conclusions: Everolimus allows calcineurin inhibitor-reduction and withdrawal after a heart transplant, resulting in improved renal function. However, adverse effects are common and lead to a high reconversion rate.

Background: Despite improvements in immunosuppressive therapy, the most advantageous combination for cardiac transplant recipients has not been established. This randomized controlled trial was performed to evaluate the efficacy and safety of 3 immunosuppressive protocols., Methods: Between 2003 and 2005, 78 de novo cardiac transplant recipients were randomized 2:2:1 to receive steroids and tacrolimus plus mycophenolate mofetil (TAC/MMF; n = 34), TAC and sirolimus (TAC/SRL; n = 29), or SRL and MMF (SRL/MMF) plus anti-thymocyte globulin (ATG; n = 15). Steroids were withdrawn after 6 months., Results: The 5-year survival was 85.3% for TAC/MMF, 93.1% for TAC/SRL, and 86.7% for SRL/MMF (p = 0.31 for TAC/MMF vs TAC/SIR; p = 0.47 for TAC/MMF vs SIR/MMF and p = 0.86 for TAC/SIR vs SIR/MMF). Despite the use of ATG, patients in the SRL/MMF group revealed numerically fewer freedom from acute rejection episodes: TAC/MMF, 82.4%; TAC/SRL, 85.2%; SRL/MMF, 73.3% (p = 0.33). Mean creatinine at 5 years revealed preservation of renal function in the SRL/MMF vs the TAC/MMF group (p = 0.045): TAC/MMF, 1.70±0.91 mg/dl; TAC/SRL, 1.44±0.65 mg/dl; and SRL/MMF, 1.25±0.46 mg/dl. Freedom from cardiac allograft vasculopathy was improved in the SRL/MMF group (93.3%) compared with TAC/MMF (73.5%) and TAC/SRL (80.8%) groups, reaching no statistical significance. Freedom from cytomegalovirus infection was TAC/MMF, 72.2%; TAC/SRL, 89.7%; and SRL/MMF, 86.7%. There was a trend toward improved freedom from cytomegalovirus infection with TAC/SRL vs TAC/MMF (p = 0.076). More frequent discontinuations of study medication occurred in SRL-based immunosuppression protocols (TAC/SRL vs TAC/MMF, p = 0.034; SRL/MMF vs TAC/MMF, p = 0.003)., Conclusions: The 3 strategies yield no survival advantage at 5 years, with higher numeric rates of rejection and adverse effects in the calcineurin inhibitor-free arm. A trend was observed in favor of freedom from cardiac allograft vasculopathy and preservation of renal function in the calcineurin inhibitor-free arm. However, the clinical relevance on outcomes is unclear because only few patients were receiving the assigned treatment protocols., (Copyright © 2013 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Purpose: Despite improvements in immunosuppressive therapy, chronic rejection, renal toxicity and malignancy are the major obstacles for long-term success after heart transplantation. We performed the worldwide first pilot-trial to evaluate the efficacy and safety of a de-novo calcineurin-inhibitor (CNI)-free immunosuppressive protocol. Between May 2003 and April 2005, 15 de-novo cardiac transplant recipients were assigned to receive sirolimus, mycophenolate mofetil and steroids. Antilymphocyte induction was given for 5 days; steroids were withdrawn after 6 months. A total of six of 15 patients received cytomegalovirus (CMV)-prophylaxis for high-risk CMV constellation (R-/D+)., Results: Survival at 1 and 5 years was 87.5%. Freedom from biopsy-proven rejection was 71.3% at 1 year and 59.4% at 5 years. Freedom from angiographically detectable vasculopathy was 100% after 5 years and only one CMV infection occurred. Mean serum creatinine was 1.43 ± 0.31 mg/dl prior to heart transplantation (HTx), 1.29 ± 0.56 mg/dl at 1 year and 1.23 ± 0.53 mg/dl at 5 years. Cholesterol was 203 ± 32 mg/dl at 1 year and 199 ± 40 mg/dl at 5 years despite statins, and hypertriglyceridaemia (223 ± 97 mg/dl) persisted after 5 years. No new-onset diabetes occurred. Surgical interventions for pericardial effusions were necessary in five patients. Nine patients discontinued sirolimus treatment temporarily because of side-effects (four acute rejections, three delayed wound healing and two gastrointestinal toxicity), all nine patients were reintroduced to sirolimus after the side-effects resolved., Summary: CNI-free immunosuppression is possible and long-term results are favourable for survival, malignancy, renal function, CMV infections and vasculopathy. On the other hand, de-novo CNI-free immunosuppression after HTx is less efficacious in preventing acute rejection and has an inferior side-effect profile.

Background: Calcineurin-inhibitor-(CNI)-induced renal failure is one major cause of morbidity in cardiac transplantation (HTx). In this prospective, randomized, multicenter trial, the impact of immunosuppressive conversion toward CNI-free (mycophenolate mofetil [MMF] and sirolimus) or a CNI-reduced immunosuppressive regimen on renal function, efficacy, and safety was evaluated., Methods: Since 2004, 63 HTx-patients (0.5-18.4 years after HTx) with CNI-based immunosuppression and reduced creatinine clearance less than 60 mL/min (39+/-15 mL/min) were included in this trial. Patients in the CNI-free-Group (group 1) were converted to sirolimus that was started with 2 mg/day until target trough levels (8-14 ng/mL) were achieved. Subsequently, CNIs were withdrawn. In CNI-reduction-Group (group 2), CNI target trough levels were reduced by 40%. In both groups MMF was continued and trough level adjusted (1.5-4 microg/mL)., Results: Patients demographics and survival (mean follow-up time: 16.7+/-9 months) was equal (100%). Renal function improved significantly after complete CNI withdrawal while remaining unchanged with CNI-reduction (Creatinine clearance after 12 months: 53+/-24 mg/dL [group 1] vs. 38+/-20 mg/dL [group 2], P=0.01). End-stage renal failure (hemodialysis) was avoided by CNI-withdrawal and occurred only after CNI reduction (n=6; P=0.01). Acute rejection episodes were more common in group 2 (4 vs. 2). Graft function remained stable (echocardiography) within both groups. Adverse events were more common in group 1 (65%) than in group 2 (n=40%) and were responsible for discontinuation in 4 and 0 cases, respectively., Conclusions: Conversion toward a CNI-free immunosuppression (Mycophenolate, sirolimus) is superior to CNI-reduced immunosuppression in improving renal failure in late HTx-recipients. However, this benefit is relativized by the increased incidence and severity of sirolimus/MMF-associated side effects.

The mammalian-target-of-rapamycin/mTOR-inhibitor sirolimus as a component of the immunosuppressive strategy after solid organ transplantation is effective at preventing allograft rejection. However, recent reports indicate that sirolimus is associated with altered sex hormone levels and impaired sperm quality parameters. Herein, we report on a case of sirolimus-associated infertility in a young male heart-lung transplant recipient and provide a detailed synopsis of potential mechanisms by which sirolimus may negatively influence spermatogenesis. Testicular immunohistochemistry, the course of sex hormone and sperm quality parameters of our patient support the hypothesis that mTOR might act as an important key regulator in the reproductive system. Fortunately, due to withdrawal of sirolimus as part of the maintenance, immunosuppression improved sperm quality and sex hormone parameters could be observed. Recently, these improvements even resulted in a spontaneous pregnancy of the patient's wife more than 1 year after the drug was withdrawn. In our view, oligospermia as a possible and at least partly reversible side-effect of mTOR inhibitors has to be taken into consideration, particularly, when administrated to young male patients.

Heart transplant recipients treated with long-term calcineurin inhibitors (CNIs) experience significant nephrotoxicity and transplant vasculopathy. Signal proliferation inhibitors might prevent the development of transplant vasculopathy. In an open, prospective pilot study, 33 primary heart transplant recipients received tacrolimus (Tac) and sirolimus (rapamycin, Rapa) with steroids. To reduce both nephrotoxicity and transplant vasculopathy at the same time, both Tac and Rapa exposure was kept low (6 to 8 ng/ml). Steroids were withdrawn successfully from all patients within 6 months. Just one acute rejection occurred at 54 days post-transplant, resulting in 0.03 acute rejection episode per patient at 1-year (primary end-point) and 2-year follow-up. Transplant vasculopathy assessed by angiogram was absent at 2 years. Graft and patient survival were 100% at 1 and 2 years. Accordingly, the survival estimate for freedom from first acute rejection, transplant vasculopathy, graft loss or death was 0.97 at 1 and 2 years. The regimen was well tolerated with only 3 patients requiring a change of study medication. Mean serum creatinine increased during the first year but returned to baseline at 2 years.

Background: Bronchiolitis obliterans syndrome (BOS) is the major problem after lung and heart-lung transplantation (LTx/HLTx). Sirolimus (Sir) and Mycophenolate (MMF) showed a promising efficacy in the treatment of BOS in animal models. The first clinical experience in converting LTx/HLTx-recipients with BOS from calcineurin inhibitor-(CNI)-based immunosuppression to a Sir-MMF based immunosuppression is reported herein., Methods: Six LTx- and five HLTx-recipients (eight men; 0.9 to 8 years after transplantation) with CNI-based immunosuppression (plus MMF) in whom BOS was diagnosed were included in the study. Mean patient age was 37+/-13 years (range 17-62 years). Sir was started with 6 mg and continued adjusted to according target trough levels (8-14 ng/ml). Subsequently, the CNIs were tapered down and finally stopped. Follow up included self determined pulmonary function tests, microbiological screening, chest radiographs, and laboratory studies, Results: Two acute rejection episodes occurred during the study period. The incidence of infection was 2.2+/-1.3 infections/patient-year after conversion. Mean FEV1 decreased after a mean follow up of 14.8+/-1.4 months: from 2.1+/-0.7 l prior conversion to 1.3+/-0.6l after conversion (P=0.03). However, graft function remained stable in three patients and progression of BOS slowed down in three patients. Overall, 2 of 10 patients died due to ongoing BOS while awaiting retransplantation, Conclusions: After BOS was diagnosed, conversion to MMF and Sir stabilized graft function only in some of the converted patients. Therefore, earlier administration of Sir-based immunosuppression might be a more promising approach. Whether conversion to CNI-free immunosuppression can actually ameliorate the extent or progression of BOS has to be investigated in randomized trials.

The impact of sirolimus on hormone levels involved in the hypothalamus-pituitary-gonad axis in male heart transplant recipients was investigated. A pair-matched analysis with 132 male heart transplant recipients on either sirolimus based- or calcineurin inhibitor-based immunosuppression was performed. Matching criteria were age, years after transplantation and creatinine levels. Measured parameters were testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), sexual hormone-binding globulin (SHBG) and free androgen index (FAI). Mean testosterone was 3.86 +/- 1.41 ng/mL in the sirolimus group and 4.55 +/- 1.94 ng/mL in the controls (p = 0.025). Serum LH was 12.82 +/- 11.19 mlU/mL in the sirolimus patients and 6.2 +/- 5.25 mlU/mL in the controls (p = 0.015). Follicle stimulating hormone levels were 13.31 +/- 18.4 mlU/mL vs. 7.32 +/- 5.53 mlU/mL, respectively (p = 0.015). The analysis revealed a significant decrease in testosterone and a significant increase in FSH and LH in the sirolimus group. The duration of sirolimus treatment correlated positively with SHBG (p < 0.01), LH (p < 0.05) and FSH (p < 0.05) and negative with the FAI (p < 0.05). Sirolimus trough levels correlated with LH and FSH levels (p < 0.01). Heart transplant recipients treated with sirolimus revealed significantly lower testosterone levels and a significant increase in gonadotropic hormones. These effects were trough-level dependent. All candidates awaiting organ transplantation should be informed about these adverse effects.

Chronic renal failure triggered by calcineurin inhibitor (CNI)-based immunosuppression is a common complication after cardiac transplantation. Sirolimus and mycophenolate mofetil (MMF) are 2 newer immunosuppressive agents with no documented nephrotoxic side effects. This case report describes a patient with ongoing chronic renal failure 10 months after cardiac transplantation on cyclosporine-based immunosuppressive therapy. Conversion of the immunosuppressive regimen from cyclosporine to sirolimus and MMF resulted in freedom from acute rejection, excellent cardiac graft function and consistently improved renal function. This case illustrates the beneficial potential of sirolimus and MMF as CNI-free and safe long-term immunosuppression in a patient with chronic renal failure after heart transplantation.

Objective: Calcineurin inhibitor (CNI)-related renal failure is a common problem after cardiac transplantation (HTx). The aim of this prospective study was to evaluate the safety and efficacy of a completely CNI-free immunosuppressive regimen [mycophenolate mofetil (MMF) and sirolimus (Sir)] in HTx-recipients with late post-transplant renal impairment., Methods: Since 2001, 30 HTx-patients (25 men, 6 women; 0.2-14.2 years after transplantation) with CNI-based immunosuppression and a serum creatinine >1.9 mg/dl were included in the study. Creatinine and cystatin levels were monitored to detect renal function. Conversion was started with 6 mg Sir or 500 mg MMF according to the pre-existing regimen and was continued with the dose adjusted to achieve target trough levels between 8 and 14 ng/ml (Sir) or 1.5 and 4 microg/ml (mycophenolate). Subsequently, the CNIs were tapered down and stopped. Clinical follow-up included endomyocardial biopsies, echocardiography and laboratory studies. Additionally, every HTx-patient treated at our centre between 1996 and 2001 due to chronic renal failure without immunosuppressive conversion and fulfilling the inclusion criteria were retrospectively analysed and acted as control group., Results: Patient demographics and 1-year survival [93 (conversion) vs 90% (control)] were compared. No acute rejection episode was detected in either group. Renal function improved significantly in the conversion group (creatinine: 3.18+/-0.71 vs 2.22+/-0.79 mg/dl, P=0.001; cystatin pre- vs post-conversion: 2.95+/-1.06 vs 2.02+/-1.1 mg/l, P=0.01). In three patients haemodialysis therapy was stopped completely after conversion. In the control group renal impairment was deteriorating, creatinine increased from 2.44+/-0.8 to 3.28+/-1 mg/dl (P=0.01). In 10 out of 33 patients chronic haemodialysis had to be initiated within 1 year. Although side effects of CNI-free immunosuppression were common (76%), no patient had to be excluded due to adverse effects., Conclusions: Conversion from CNI-based immunosuppression to MMF and Sir in HTx-patients with chronic renal failure was safe, preserved graft function and improved renal function.

Background: Calcineurin-inhibitor (CNI)-related renal failure is a common problem after cardiac transplantation (HTx). The aim of this study was to introduce a CNI-free immunosuppressive regimen to HTx recipients with late posttransplant renal impairment and to evaluate the impact of conversion to this new immunosuppression (mycophenolate mofetil [MMF] and sirolimus [Sir]) treatment on renal function., Methods and Results: Thirty-one HTx patients (25 men, 6 women; 0.2-14.2 years after transplantation) with CNI-based immunosuppression and a serum creatinine greater than 1.9 mg/dL were included in the study. Creatinine and cystatin levels were monitored to detect renal function. Mean patient age was 50+/-14 (range 19-74) years. Conversion was started with 6 mg Sir, continued with 2 mg, and the dose was adjusted to achieve target trough levels between 8 and 14 ng/mL. MMF was continued with trough level adjusted (1.5-4 microg/mL). Subsequently, the CNIs were tapered down and stopped. Clinical follow-up (first and every 3 months after conversion) included endomyocardial biopsies, echocardiography, and laboratory studies. Survival was 90% after a mean follow-up of 13+/-95 months. No acute rejection episode was detected during the study period. Renal function improved significantly after conversion: creatinine preconversion vs. postconversion: 3.14+/-0.76 mg/dL vs. 2.14+/-0.83 mg/dL, P =0.001. Cystatin preconversion vs. postconversion: 2.95+/-1.06 mg/L vs. 2.02+/-1.1 mg/L, P =0.01. In three patients, hemodialysis therapy was stopped completely after conversion. Graft function remained stable. Fractional shortening preconversion vs. postconversion: 36.9+/-6% vs. 36.4+/-6%. There were no serious adverse events. One patient had to be excluded because of noncompliance., Conclusions: Conversion from CNI-based immunosuppression to MMF and Sir in HTx patients with chronic renal failure was safe, preserved graft function, and improved renal function.