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1.
Clin Transplant ; 31(11)2017 Nov.
Article in English | MEDLINE | ID: mdl-28940521

ABSTRACT

BACKGROUND: The development of donor-specific antibodies (DSA) to human leukocyte antigens (HLA) has been associated with acute rejection and allograft failure after heart transplantation. Not all DSA, however, can fix complement. METHODS: To determine the association between complement-fixing DSA and heart transplant outcomes, we retrospectively analyzed results obtained using the C1q solid-phase assay that specifically detects complement-fixing DSA in parallel with the standard IgG assay in 121 adult heart transplant recipients. RESULTS: The 52 recipients who developed post-transplant DSA had a higher incidence of acute cellular rejection (58% vs 19%, P < .001) and antibody-mediated rejection (29% vs 7%, P < .001) than the 69 recipients without DSA. The 24 recipients with C1q+ DSA had more antibody-mediated rejection than the 28 recipients with C1q- DSA (46% vs 14%, P = .012), but there was no difference in the incidence of acute cellular rejection between these two groups. Patients with post-transplant DSA had higher mortality than patients with no DSA (29% vs 13%, P = .031), mainly due to increased incidence of acute rejection. No differences in survival were found between recipients with C1q+ DSA and C1q- DSA. CONCLUSIONS: Routine monitoring of DSA post-transplant, and their characterization using the C1q assay, may provide prognostic information for acute rejection after heart transplantation.


Subject(s)
Complement C1q/immunology , Graft Rejection/immunology , Graft Survival/immunology , HLA Antigens/immunology , Heart Transplantation , Isoantibodies/immunology , Tissue Donors , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Transplantation, Homologous
2.
Transplant Proc ; 45(6): 2406-9, 2013.
Article in English | MEDLINE | ID: mdl-23953556

ABSTRACT

BACKGROUND: We evaluated the potential effects of granulocyte colony-simulating factor (G- CSF) on the incidence of rejection and allograft vasculopathy in heart transplant recipients. METHODS: Of 247 patients undergoing heart transplantation from 2000 to 2007, 52 (21%) developed leukopenia (white blood cell [WBC] <2.5 × 10(9) cells/L) in the absence of active infection, rejection, or malignancy. In 24 (46%) patients a clinical decision was made to treat the leukopenia with G-CSF (G-CSF group), and 28 (54%) Patients received no G-CSF (non-GCSF group). Patients followed up for 1 year after the period of leukopenia were assessed for allograft vasculopathy and acute rejection incidence. RESULTS: At baseline, the G-CSF group and the non-GCSF group did not differ in age, gender, race, heart failure etiology, creatinine, left ventricular ejection fraction (LVEF) or immunosupressive regimen. During 1-year follow-up there were no deaths in the G-CSF group, and 1 death in the non-GCSF group (P = .34). The incidence of rejection or progressive allograft vasculopathy was lower in the G-CSF group when compared with the non-GCSF group (2 [8%] vs 15 [53%]; P < .01). Multivariate analysis identified both prior rejection episodes and G-CSF therapy as factors associated with the combined end-point of rejection or progressive allograft vasculopathy (odds ratio [OR] = 7.89 [1.67-37.2] and OR = 0.09 [0.02-0.52], respectively). CONCLUSIONS: G-CSF therapy appears to be associated with a decreased incidence of acute rejection episodes or allograft vasculopathy in heart transplant recipients, suggesting a potential immunomodulatory effect of G-CSF.


Subject(s)
Coronary Artery Disease/prevention & control , Graft Rejection/prevention & control , Granulocyte Colony-Stimulating Factor/therapeutic use , Heart Transplantation , Immunologic Factors/therapeutic use , Leukopenia/drug therapy , Acute Disease , Adult , Aged , Allografts , California/epidemiology , Chi-Square Distribution , Coronary Artery Disease/epidemiology , Female , Graft Rejection/epidemiology , Heart Transplantation/adverse effects , Humans , Incidence , Leukocyte Count , Leukopenia/blood , Leukopenia/diagnosis , Leukopenia/epidemiology , Male , Middle Aged , Multivariate Analysis , Odds Ratio , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome
3.
J Perinatol ; 33(4): 251-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23079774

ABSTRACT

Medical researchers have called for new forms of translational science that can solve complex medical problems. Mainstream science has made complementary calls for heterogeneous teams of collaborators who conduct transdisciplinary research so as to solve complex social problems. Is transdisciplinary translational science what the medical community needs? What challenges must the medical community overcome to successfully implement this new form of translational science? This article makes several contributions. First, it clarifies the concept of transdisciplinary research and distinguishes it from other forms of collaboration. Second, it presents an example of a complex medical problem and a concrete effort to solve it through transdisciplinary collaboration: for example, the problem of preterm birth and the March of Dimes effort to form a transdisciplinary research center that synthesizes knowledge on it. The presentation of this example grounds discussion on new medical research models and reveals potential means by which they can be judged and evaluated. Third, this article identifies the challenges to forming transdisciplines and the practices that overcome them. Departments, universities and disciplines tend to form intellectual silos and adopt reductionist approaches. Forming a more integrated (or 'constructionist'), problem-based science reflective of transdisciplinary research requires the adoption of novel practices to overcome these obstacles.


Subject(s)
Academic Medical Centers/methods , Patient Care Team/organization & administration , Premature Birth , Translational Research, Biomedical , Female , Humans , Interdisciplinary Communication , Interdisciplinary Studies , Interprofessional Relations , Pregnancy , Premature Birth/epidemiology , Premature Birth/etiology , Premature Birth/therapy , Research Design , Translational Research, Biomedical/methods , Translational Research, Biomedical/organization & administration , United States
4.
Clin Transplant ; 25(5): E475-86, 2011.
Article in English | MEDLINE | ID: mdl-21592231

ABSTRACT

Although malignancy is a major threat to long-term survival of heart transplant (HT) recipients, clear strategies to manage immunosuppression in these patients are lacking. Several lines of evidences support the hypothesis of an anticancer effect of proliferation signal inhibitors (PSIs: mammalian target of rapamycin [mTOR] inhibitors) in HT recipients. This property may arise from PSI's ability to replace immunosuppressive therapies that promote cancer progression, such as calcineurin inhibitors or azathioprine, and/or through their direct biological actions in preventing tumor development and progression. Given the lack of randomized studies specifically exploring these issues in the transplant setting, a collaborative group reviewed current literature and personal clinical experience to reach a consensus aimed to provide practical guidance for the clinical conduct in HT recipients with malignancy, or at high risk of malignancy, with a special focus on advice relevant to potential role of PSIs.


Subject(s)
Cell Proliferation/drug effects , Heart Diseases/complications , Heart Transplantation/adverse effects , Immunosuppressive Agents/therapeutic use , Neoplasms/drug therapy , Neoplasms/etiology , Postoperative Complications , Heart Diseases/surgery , Humans
5.
Am J Transplant ; 8(9): 1769-74, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18557718

ABSTRACT

Human heart transplantation started 40 years ago. Medical records of all cardiac transplants performed at Stanford were reviewed. A total of 1446 heart transplantations have been performed between January 1968 and December 2007 with an increase of 1-year survival from 43.1% to 90.2%. Sixty patients who were transplanted between 1968 and 1987 were identified who survived at least 20 years. Twenty-year survivors had a mean age at transplant of 29.4 +/- 13.6 years. Rejection-free and infection-free 1-year survivals were 14.3% and 18.8%, respectively. At their last follow-up, 86.7% of long-term survivors were treated for hypertension, 28.3% showed chronic renal dysfunction, 6.7% required hemodialysis, 10% were status postkidney transplantation, 13.3% were treated for diabetes mellitus, 36.7% had a history of malignancy and 43.3% had evidence of allograft vasculopathy. The half-life conditional on survival to 20 years was 28.1 years. Eleven patients received a second heart transplant after 11.9 +/- 8.0 years. The most common causes of death were allograft vasculopathy (56.3%) and nonlymphoid malignancy (25.0%). Twenty-year survival was achieved in 12.5% of patients transplanted before 1988. Although still associated with considerable morbidity, long-term survival is expected to occur at much higher rates in the future due to major advances in the field over the past decade.


Subject(s)
Academic Medical Centers , Graft Rejection/epidemiology , Graft Rejection/surgery , Heart Transplantation/mortality , Survivors , Adolescent , Adult , Female , Graft Survival , Heart Transplantation/statistics & numerical data , Humans , Immunosuppression Therapy , Immunosuppressive Agents , Male , Morbidity , Survival Analysis , United States/epidemiology
6.
Transplant Proc ; 39(10): 2937-50, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18089298

ABSTRACT

While advances in immunosuppressive therapy have allowed dramatic improvements in the control of acute allograft rejection, there is still a need to improve long-term graft and patient survival rates following renal and heart transplantation. Among the recognized threats to long-term organ survival are chronic allograft dysfunction in the form of chronic allograft nephropathy and cardiac allograft vasculopathy, with long-term patient morbidity and mortality further compromised by higher than normal rates of posttransplant cardiovascular disease, infection, and malignancy. A growing body of evidence finds that the selection and dosing of immunosuppressive therapies can have great influence on long-term transplantation outcomes. Early evidence suggests that the proliferation signal inhibitors (PSIs), everolimus and sirolimus, might offer effective immunosuppressive activity together with antiproliferative effects that may address some of the unmet needs in the long-term therapeutic management of the posttransplant patient. This review summarizes the emerging evidence for employing PSI-based immunosuppression to seek a balance between the goals of maximizing graft and patient survival, while minimizing the risks of adverse events and long-term complications. Based on the proceedings of an international gathering of nephrologists, cardiologists and surgeons at the inaugural PSI Forum meeting "Proliferation signal inhibitors in transplantation: questions at the cutting edge," this paper aims to provide both an evidence base and practical guidance for transplant physicians seeking to optimize their use of PSI treatment and highlights avenues of ongoing research into the clinical potential of this class of immunosuppressive therapy.


Subject(s)
Cell Division/drug effects , Immunosuppressive Agents/therapeutic use , Sirolimus/analogs & derivatives , Transplantation Immunology , Everolimus , Graft Rejection/prevention & control , Humans , Signal Transduction/drug effects , Sirolimus/therapeutic use , Transplantation, Homologous/immunology
7.
Am J Transplant ; 7(10): 2388-95, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17845572

ABSTRACT

The ongoing shortage of donors for cardiac transplantation has led to a trend toward acceptance of donor hearts with some structural abnormalities including left ventricular hypertrophy. To evaluate the outcome in recipients of donor hearts with increased left ventricular wall thickness (LVWT), we retrospectively analyzed data for 157 cardiac donors and respective recipients from January 2001 to December 2004. There were 47 recipients of donor heart with increased LVWT >or=1.2 cm, which constituted the study group and 110 recipients of a donor heart with normal LVWT < 1.2 cm that formed the control group. At 3 +/- 1.5 years, recipient survival was lower (50% vs. 82%, p = 0.0053) and incidence of allograft vasculopathy was higher (50% vs. 22%, p = 0.05) in recipients of donor heart with LVWT > 1.4 cm as compared to LVWT 1.4 cm (p = 0.003), recipient preoperative ventricular assist device (VAD) support (p = 0.04) and bypass time > 150 min (p = 0.05) were predictors of reduced survival. Our results suggest careful consideration of donor hearts with echocardiographic evidence of increased LVWT in the absence of hypovolemia, because they may be associated with poorer outcomes; such hearts should potentially be reserved only for the most desperately ill recipients.


Subject(s)
Heart Transplantation/pathology , Heart Transplantation/physiology , Heart Ventricles/pathology , Myocardium/pathology , Tissue Donors/statistics & numerical data , Ventricular Dysfunction, Left/pathology , Adult , Antihypertensive Agents/therapeutic use , Biopsy , Coronary Angiography , Echocardiography , Female , Heart Transplantation/immunology , Heart Transplantation/mortality , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Patient Selection , Retrospective Studies , Survival Analysis , Tissue Donors/supply & distribution , Tissue and Organ Harvesting/methods , Treatment Outcome , Ventricular Dysfunction, Left/diagnostic imaging
8.
Am J Transplant ; 6(5 Pt 1): 986-92, 2006 May.
Article in English | MEDLINE | ID: mdl-16611334

ABSTRACT

Sirolimus was introduced in de novo immunosuppression at Stanford University in view of its favorable effects on reduced rejection and cardiac allograft vasculopathy. After an apparent increase in the incidence of post-surgical wound complications as well as symptomatic pleural and pericardial effusions, we reverted to a mycophenolate mofetil (MMF)-based regimen. This retrospective study compared the outcome in heart transplant recipients on sirolimus (48 patients) with those on MMF (46 patients) in de novo immunosuppressive regimen. The incidence of any post-surgical wound complication (52% vs. 28%, p=0.019) and deep surgical wound complication (35% vs. 13%, p=0.012) was significantly higher in patients on sirolimus than on MMF. More patients on sirolimus also had symptomatic pleural (p=0.035) and large pericardial effusions (p=0.033) requiring intervention. Logistic regression analysis showed sirolimus (p=0.027) and longer cardiac bypass time (OR=1.011; p=0.048) as risk factors for any wound complication. Sirolimus in de novo immunosuppression after cardiac transplantation was associated with a significant increase in the incidence of post-surgical wound healing complications as well as symptomatic pleural and pericardial effusions.


Subject(s)
Heart Transplantation/immunology , Immunosuppressive Agents/adverse effects , Mycophenolic Acid/analogs & derivatives , Sirolimus/adverse effects , Wound Healing/drug effects , Female , Humans , Incidence , Male , Middle Aged , Mycophenolic Acid/adverse effects , Postoperative Complications/chemically induced , Postoperative Complications/epidemiology , Racial Groups , Retrospective Studies , Wounds and Injuries/epidemiology , Wounds and Injuries/immunology
9.
Am J Transplant ; 6(5 Pt 1): 993-7, 2006 May.
Article in English | MEDLINE | ID: mdl-16611335

ABSTRACT

UNLABELLED: The mycophenolate mofetil (MMF) trial involved 650 heart transplant patients from 28 centers who received MMF or azathioprine (AZA), both in combination with cyclosporine and corticosteroids. Baseline and 1-year intravascular ultrasound (IVUS) were performed in 196 patients (102 MMF and 94 AZA) with no differences between groups in IVUS results analyzed by morphometric analysis (average of 10 evenly spaced sites, without matching sites between studies). Baseline to first-year IVUS data can also be analyzed by site-to-site analysis (matching sites between studies), which has been reported to be more clinically relevant. Therefore, we used site-to-site analysis to reanalyze the multicenter MMF IVUS data. RESULTS: IVUS images were reviewed and interpretable in 190 patients (99 MMF and 91 AZA) from the multicenter randomized trial. The AZA group compared to the MMF group had a larger number of patients with first-year maximal intimal thickness (MIT)>or=0.3 mm (43% vs. 23%, p=0.005), a greater decrease in the mean lumen area (p=0.02) and a decrease in the mean vessel area (the area actually increased in the MMF group, p=0.03). CONCLUSION: MMF-treated heart transplant patients compared to AZA-treated patients, both concurrently on cyclosporine and corticosteroids, in this study have significantly less progression of first-year intimal thickening.


Subject(s)
Heart Transplantation/immunology , Immunosuppressive Agents/therapeutic use , Mycophenolic Acid/analogs & derivatives , Tunica Intima/pathology , Adrenal Cortex Hormones/therapeutic use , Adult , Azathioprine/therapeutic use , Cyclosporine/therapeutic use , Double-Blind Method , Drug Therapy, Combination , Female , Follow-Up Studies , Histocompatibility Testing , Humans , Male , Middle Aged , Mycophenolic Acid/therapeutic use , Time Factors , Tunica Intima/diagnostic imaging , Tunica Intima/drug effects , Ultrasonography
10.
Transplant Proc ; 37(4 Suppl): 4S-17S, 2005 May.
Article in English | MEDLINE | ID: mdl-15809102

ABSTRACT

Graft failure and mortality among heart transplant recipients remains higher than in populations receiving renal transplants. A major cause of graft loss is cardiac allograft vasculopathy (CAV), a condition characterized by diffuse thickening of coronary blood vessels. CAV often progresses silently, with major cardiac events (eg, ventricular arrhythmia) being the first presentation. Better diagnosis and monitoring of CAV is now possible with intravascular ultrasonography, a sensitive technique for measuring intimal thickness. To date, immunosuppressants have shown little efficacy for preventing CAV. However, a new class of agents, proliferation signal inhibitors (sirolimus and everolimus), have shown considerable efficacy in this regard and for preventing rejection. In an open-label trial, sirolimus therapy was associated with less intimal and medial proliferation than azathioprine. More robust evidence is available from a larger-scale, double-blind trial involving everolimus. At 12-month follow-up the incidence of CAV was significantly lower in patients receiving everolimus (35.7% and 30.4% for everolimus 1.5 and 3.0 mg/d vs 52.8% for azathioprine; P < .05). Sirolimus and everolimus were also associated with a lower rate of cytomegalovirus infection. As with other immunosuppressants, these agents are associated with adverse events (eg, hyperlipidemia), but they can be managed. Coadministration with calcineurin inhibitors (CNIs) can exacerbate CNI-related nephrotoxicity, but evidence suggests that everolimus administered with reduced-exposure cyclosporine in the maintenance phase preserves renal function without loss of immunosuppressive efficacy. Reduced CNI dosing in de novo patients is also a potential future benefit. Proliferation signal inhibitors have considerable potential for improving outcomes in heart transplantation.


Subject(s)
Heart Transplantation/standards , Cell Division , Clinical Trials as Topic , Coronary Vessels/pathology , Graft Rejection/pathology , Graft Rejection/prevention & control , Heart Transplantation/immunology , Heart Transplantation/pathology , Humans , Immunosuppressive Agents/therapeutic use , Postoperative Complications/epidemiology , Signal Transduction/physiology , Transplantation, Homologous , Treatment Failure , Treatment Outcome
11.
Transplant Proc ; 37(10): 4145-9, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16387066

ABSTRACT

The proliferation signal inhibitor everolimus is efficacious for reducing the incidence of acute rejection and cardiac allograft vasculopathy (CAV) in heart transplantation; and it has the potential to facilitate cyclosporine (CsA) minimization in this setting. Reducing CsA dose in heart transplantation is dependent on everolimus trough blood levels of 3 to 8 ng/mL being achieved. Physicians experienced in the use of everolimus aim for CsA trough blood levels of 175 to 200 ng/mL in everolimus-treated patients during the initial 3 months following heart transplantation. Modeling data from the heart pivotal study suggest that CsA trough blood levels of 100 ng/mL at 6 months posttransplant could be targeted without loss of efficacy, and antibody induction therapy may assist with this approach. Target CsA trough blood levels for maintenance patients could possibly be reduced from the current 80 to 100 ng/mL to 50 to 80 ng/mL. Maintenance patients with renal dysfunction or CAV may benefit from conversion to everolimus and subsequent reduction in CsA trough blood levels (eg, by 50%). Initial experience of everolimus with reduced CsA trough blood levels in heart transplantation is favorable, but there is scope for further study.


Subject(s)
Heart Transplantation/immunology , Immunosuppressive Agents/therapeutic use , Kidney/pathology , Sirolimus/analogs & derivatives , Cyclosporine/pharmacokinetics , Cyclosporine/toxicity , Everolimus , Graft Survival/drug effects , Humans , Immunosuppressive Agents/blood , Immunosuppressive Agents/pharmacokinetics , Immunosuppressive Agents/toxicity , Kidney/drug effects , Metabolic Clearance Rate , Sirolimus/blood , Sirolimus/pharmacokinetics , Sirolimus/therapeutic use , Sirolimus/toxicity
13.
Transplantation ; 72(10): 1647-52, 2001 Nov 27.
Article in English | MEDLINE | ID: mdl-11726825

ABSTRACT

BACKGROUND: Cytomegalovirus (CMV) disease was previously shown to be unaltered by a 28-day course of ganciclovir compared with placebo in seronegative recipients of hearts from seropositive donors (D+/R-). This study tests the hypothesis that a combination of ganciclovir plus CMV hyperimmune globulin (CMVIG) is more effective than ganciclovir alone for preventing acute CMV illness and its long-term sequelae. METHODS: The study population receiving CMVIG (n=80) included 27 heart transplant recipients (D+/R-) and 53 heart-lung and lung transplant recipients (R+ and/or D+). Each group was matched with historical controls who underwent transplantation within the preceding 2-3 years. Outcome measures compared were as follows: 3-year incidence of CMV disease; fungal infection; acute rejection; survival; rates and severity of transplant coronary artery disease (in heart patients) defined by intimal thickness (ultrasound) and coronary artery stenosis (angiographic); and incidence and death from obliterative bronchiolitis defined by pathological criteria on endobronchial biopsy specimens (in heart-lung/lung patients). RESULTS: Patients treated with CMVIG had a higher disease-free incidence of CMV, lower rejection incidence, and higher survival rate compared with the patients treated with ganciclovir alone. The coronary artery intimal thickness and the prevalence of intimal thickening were lower in the patients receiving CMVIG. Heart-lung and lung transplant patients treated with CMVIG had lower incidences of obliterative bronchiolitis and death from obliterative bronchiolitis and longer survival compared with the patients treated with ganciclovir alone. CONCLUSIONS: CMVIG plus ganciclovir seems to be more effective that ganciclovir alone for preventing the sequelae of CMV infection. A prospective randomized study is required to confirm these observations.


Subject(s)
Cytomegalovirus Infections/prevention & control , Ganciclovir/administration & dosage , Heart Transplantation/adverse effects , Heart-Lung Transplantation/adverse effects , Immunoglobulins/administration & dosage , Lung Transplantation/adverse effects , Adult , Aged , Cause of Death , Female , Humans , Immunoglobulins, Intravenous , Lymphoproliferative Disorders/prevention & control , Male , Middle Aged
14.
Pediatr Radiol ; 31(12): 827-35, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11727015

ABSTRACT

BACKGROUND: Migration of monocytes into the arterial wall is an early finding of atherosclerosis. Monocytes are attracted to sites of vascular endothelial cell injury, the initiating event in the development of atheromatous disease, by a chemokine known as monocyte chemoattractant protein-1 (MCP-1). Injured vascular endothelial and smooth muscle cells selectively secrete MCP-1. OBJECTIVE: This study was performed to determine if radiolabeled MCP-1 would co-localize at sites of monocyte/macrophage concentration in an experimental model of transplant-induced vasculopathy in diabetic animals. MATERIALS AND METHODS: Hearts from 3-month-old male Zucker rats, heterozygote (Lean) or homozygote (Fat) for the diabetes-associated gene fa, were transplanted into the abdomens of genetically matched recipients. Lean and Fat animals were then fed normal or high-fat diets for 90 days. RESULTS: At 90 days significant increases (P < 0.013) of MCP-1 graft uptake were seen at imaging and confirmed on scintillation gamma well counting studies in Lean (n = 5) and Fat (n = 12) animals, regardless of diet, 400 % and 40 %, above control values, respectively. MCP-1 uptake of native and grafted hearts correlated with increased numbers of perivascular macrophages (P < 0.02), as seen by immunostaining with an antibody specific for macrophages (ED 2). CONCLUSION: Radiolabeled MCP-1 can detect abnormally increased numbers of perivascular mononuclear cells in native and grafted hearts in prediabetic rats. MCP-1 may be useful in the screening of diabetic children for early atherosclerotic disease.


Subject(s)
Chemokine CCL2 , Coronary Artery Disease/diagnostic imaging , Coronary Vessels/diagnostic imaging , Heart Transplantation/diagnostic imaging , Animals , Blood Glucose , Chemokine CCL2/pharmacokinetics , Coronary Artery Disease/immunology , Coronary Vessels/pathology , Diabetes Complications , Disease Models, Animal , Heart Transplantation/immunology , Immunohistochemistry , Leukocytes, Mononuclear/diagnostic imaging , Male , Radionuclide Imaging , Rats , Rats, Zucker
15.
Circulation ; 104(21): 2615-9, 2001 Nov 20.
Article in English | MEDLINE | ID: mdl-11714659

ABSTRACT

BACKGROUND: Allograft coronary atherosclerosis (TxCAD) is the leading cause of death after the first year after transplantation. TxCAD is believed to be a form of chronic rejection of the cardiac allografts. This study was undertaken to determine whether TxCAD could develop in the absence of a cellular alloimmune response. METHODS AND RESULTS: Inbred lean Zucker rats (>26 generations) served as donors and recipients of the cardiac grafts. Donor hearts were explanted at 60 or 90 days. Explanted hearts were processed for coronary artery histological analysis. Cytokine expression was determined by reverse transcription-polymerase chain reaction, and the presence of T cells within the explanted hearts was evaluated by immunohistochemistry. Forty-six transplantations were made, and TxCAD developed in all but one of the transplanted hearts. Overall, one third of the vessels examined were affected by TxCAD, and in roughly half of these vessels, the disease was severe. Native hearts were free of atherosclerosis. Interleukin-2 was absent from the transplanted hearts, and T cells were present in minimal amounts (<1 per low-power field). CONCLUSIONS: TxCAD developed in the absence of a cellular alloimmune response in these genetically similar donors and recipients. The observed TxCAD was significant and comparable to what is found in rat allografting models.


Subject(s)
Coronary Artery Disease/etiology , Disease Models, Animal , Heart Transplantation/adverse effects , Animals , Blood Glucose/metabolism , Coronary Artery Disease/metabolism , Coronary Artery Disease/pathology , Cytokines/biosynthesis , Cytokines/genetics , Cytokines/immunology , Female , Immunohistochemistry , Lipids/blood , Male , RNA, Messenger/biosynthesis , Rats , Rats, Zucker , T-Lymphocytes/immunology , Transplantation Tolerance
16.
Clin Transplant ; 15(4): 247-52, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11683818

ABSTRACT

BACKGROUND: Hyperhomocysteinemia is an independent risk factor for coronary disease and elevated plasma homocysteine levels have been documented in heart transplant recipients. The aim of this study was to test the hypothesis that homocysteine levels are associated with presence or absence of transplant coronary artery disease. METHODS: Forty-three non-smoking adults were recruited, all of whom had received a heart transplant between 2 and 7 yr previously. All 43 had blood drawn for fasting homocysteine level on the day of presentation. All patients had undergone diagnostic coronary angiography within the past 6 months. RESULTS: For all patients, the average fasting plasma homocysteine level was 17.0+/-SD 6.6 micromol/L with a range from 6.0 to 36.9 micromol/L. Twenty-six patients (60%) had fasting plasma homocysteine levels above 15.0 micromol/L. On the basis of arteriography, patients were categorized as those with angiographically normal (n=22) or abnormal (n=21) coronary arteries. There was no difference in the mean plasma homocysteine level comparing patients with angiographically normal (17.2+/-SD 7.0 micromol/L) to those with abnormal (16.8+/-SD 6.2 micromol/L) coronary arteries. Plasma homocysteine levels increased with increasing plasma creatinine levels (r=0.63, p<0.0001) and with decreasing vitamin B6 levels (r=-0.56, p<0.0001). CONCLUSIONS: Mild hyperhomocysteinemia is a consistent finding among heart transplant recipients. This finding was not associated with transplant coronary artery disease in our patients. The combination of renal dysfunction and vitamin B6 deficiency may explain the unusual prevalence of hyperhomocysteinemia in heart transplant recipients.


Subject(s)
Coronary Disease/complications , Heart Transplantation/adverse effects , Homocysteine/blood , Hyperhomocysteinemia/complications , Adult , Aged , Coronary Angiography , Coronary Disease/blood , Creatinine/blood , Cross-Sectional Studies , Female , Humans , Hyperhomocysteinemia/blood , Linear Models , Male , Middle Aged , Vitamin B 12/blood , Vitamin B 6/blood
17.
Drug Saf ; 24(10): 755-66, 2001.
Article in English | MEDLINE | ID: mdl-11676303

ABSTRACT

Cardiovascular disease is now the leading cause of death in transplant recipients. This is due, in part, to the vulnerability of these patients to a complicated set of conditions including hypertension, diabetes mellitus, and post-transplant hyperlipidaemia (PTHL). PTHL is characterised by persistent elevations in total serum cholesterol, low density lipoprotein cholesterol and triglyceride levels. The causes of PTHL are complex and not fully understood, however several classes of immunosuppressants including the corticosteroids, rapamycins and calcineurin inhibitors, appear to play a role. PTHL has been observed in most studies in which patients received calcineurin inhibitor-based regimens, and has been observed with both tacrolimus and cyclosporin. Comparing these calcineurin inhibitors with regard to the relative incidence or severity of PTHL occurring during treatment is difficult because of the use of higher doses of corticosteroids in cyclosporin-based regimens, as compared with tacrolimus-based regimens. However, current expert opinion suggests that the discrepancies in the relative incidence and severity of PTHL are largely accounted for by this difference in corticosteroid dose. At this point in time, evidence for potential differences is scant and inconclusive. Further study is needed, not only to investigate differences in lipid profile, but also of the relative effects of these immunosuppressants on long term graft function as well as on cardiovascular morbidity and mortality. PTHL can be successfully managed with a combination of dietary management, reduction and, if appropriate, withdrawal of corticosteroids, and the administration of lipid-lowering drugs. With this combination of therapeutic options, the threats to long term health posed by PTHL may be effectively addressed.


Subject(s)
Calcineurin Inhibitors , Hyperlipidemias/etiology , Immunosuppressive Agents/adverse effects , Organ Transplantation/adverse effects , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/etiology , Clinical Trials as Topic , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hyperlipidemias/therapy , Immunosuppression Therapy/adverse effects , Immunosuppression Therapy/methods , Postoperative Complications
18.
Liver Transpl ; 7(9): 755-61, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11552207

ABSTRACT

Patients with end-stage liver disease and coronary artery disease (CAD) being considered for orthotopic liver transplantation (OLT) present a difficult dilemma. The availability of multiple screening tests and newer treatment options for CAD prompted this review. Recent data suggest that the prevalence of CAD in patients with cirrhosis is much greater than previously believed and likely mirrors or exceeds the prevalence rate in the healthy population. The morbidity and mortality of patients with CAD who undergo OLT without treatment are unacceptably high, making identification of patients with CAD before OLT an important consideration. Patients with documented CAD or major clinical predictors of CAD should undergo cardiac catheterization before OLT. Those with advanced CAD not amenable to interventional therapy or with poor cardiac function are not candidates for OLT. Dobutamine stress echocardiogram appears to be an excellent means of screening patients with intermediate or minor clinical predictors of CAD before OLT. Patients found to have mild or moderate CAD should be aggressively treated medically and, if necessary and feasible based on hepatic reserve, by percutaneous or, less likely, surgical intervention pre-OLT to correct obstructive coronary lesions. Prospective studies regarding optimal screening strategies for the presence of CAD and the indications, timing, and outcomes of interventional therapy in patients with advanced cirrhosis are lacking and much needed.


Subject(s)
Coronary Disease/diagnosis , Coronary Disease/therapy , Liver Transplantation , Coronary Disease/complications , Coronary Disease/epidemiology , Humans , Liver Failure/complications , Liver Failure/surgery , Prevalence , Treatment Outcome
19.
J Heart Lung Transplant ; 20(7): 709-17, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11448795

ABSTRACT

BACKGROUND: Tricuspid regurgitation (TR) is common after heart transplantation. However, the incidence of severe TR and the incidence of symptoms after echocardiographic diagnosis of severe TR have not been documented. The purpose of this study is to determine the incidence of severe TR and its clinical significance in the heart transplant population. METHODS: We reviewed echocardiograms (echo) of all heart transplant patients coming for regular echocardiographic follow-up between 1990 and 1995. We reviewed the charts of all patients who had echo diagnosis of severe TR. RESULTS: A total of 336 patients had echo follow-up during this time period. The number of months post-heart transplant to last echo was 54 +/- 50 (range, 1 to 265 months). Ninety patients had moderate TR and 23 patients had severe TR. Mean time from heart transplantation to diagnosis of severe TR was 43 +/- 38 months (range, 1 to 132). Using Cutler-Ederer analysis, at 5 years, 92.2% of surviving patients were free from severe TR. At 10 years, 85.8% of surviving patients were free from severe TR. Of the 23 patients with severe TR, 17 had charts available for review. The mean number of prior endomyocardial biopsies was 28 +/- 21 (range, 3 to 88). These patients were followed for 35 +/- 18 months after diagnosis. During this period, they developed significant heart failure and peripheral edema. Six patients eventually underwent tricuspid valve replacement. CONCLUSIONS: Moderate to severe TR commonly occurs following heart transplantation. Severe TR is associated with significant morbidity.


Subject(s)
Heart Transplantation/statistics & numerical data , Tricuspid Valve Insufficiency/epidemiology , Adult , Ascites/epidemiology , Bioprosthesis , Biopsy/statistics & numerical data , California/epidemiology , Cohort Studies , Comorbidity , Coronary Disease/epidemiology , Echocardiography , Follow-Up Studies , Graft Rejection , Heart Transplantation/adverse effects , Heart Transplantation/pathology , Heart Valve Prosthesis , Humans , Incidence , Middle Aged , Prevalence , Retrospective Studies , Tricuspid Valve/surgery , Tricuspid Valve Insufficiency/diagnostic imaging , Tricuspid Valve Insufficiency/surgery
20.
Circulation ; 103(17): 2144-52, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11331254

ABSTRACT

BACKGROUND: This study examines the hypothesis that metabolic abnormalities of dysmetabolic syndrome are risk factors for transplant coronary artery disease (TxCAD). METHODS AND RESULTS: Sixty-six patients without overt diabetes, 2 to 4 years after surgery, underwent intracoronary ultrasound (ICUS), measurement of plasma glucose and insulin after oral glucose (75 g), and fasting lipid and lipoproteins. TxCAD incidence by angiography or autopsy was prospectively determined during subsequent follow-up (8 years). Coronary artery intimal thickness (IT) and subsequent outcomes were compared in patients stratified as having "high" versus "low" plasma glucose (>8.9 mmol/L) and insulin (>760 pmol/L) 2 hours after glucose challenge; and "abnormal" versus "normal" fasting lipid and lipoprotein concentrations as defined by the National Cholesterol Education PROGRAM: Patients with high glucose or insulin concentrations had greater IT: 0.38+/-0.05 versus 0.22+/-0.02 mm, P0.3 mm than with IT

Subject(s)
Coronary Artery Disease/epidemiology , Heart Transplantation , Insulin Resistance , Metabolic Syndrome/blood , Postoperative Complications/epidemiology , Adult , Aged , Blood Glucose/analysis , Cause of Death , Cohort Studies , Coronary Artery Disease/blood , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/etiology , Cross-Sectional Studies , Disease-Free Survival , Glucose Tolerance Test , Heart Transplantation/mortality , Humans , Insulin/blood , Life Tables , Lipids/blood , Lipoproteins/blood , Metabolic Syndrome/complications , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/etiology , Postoperative Complications/metabolism , Prospective Studies , Risk Factors , Survival Analysis , Tunica Intima/diagnostic imaging , Ultrasonography
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