Apoptotic death of infiltrating cells in human cardiac allografts is regulated by IL-2, FASL, and FLIP

INTRODUCTION

In vitro studies have shown that apoptotic cell death is triggered by a IL-2-dependent activation of the Fas-FasL pathway and that this pathway can be inhibited by FLIP.

METHODS

To define whether FLIP regulates apoptotic death of graft infiltrating T-cells during IL-2-mediated rejection, we analyzed endomyocardial biopsies (EMB) from cardiac allograft recipients for CD3, DNA strand breaks (TUNEL assay), FLIP (mRNA and protein), and FasL mRNA expression.

RESULTS

Apoptosis was present in CD3+ T-cell infiltrates. The number of TUNEL-stained mononuclear cells was inversely correlated with FLIP mRNA expression levels (P=.09). FLIP protein was present in 5% to 10% of the infiltrating cells and was constitutively produced by cardiomyocytes irrespective of the rejection grade. Rejection biopsies had elevated IL-2 and FasL mRNA expression levels compared to the expression levels before and after acute rejection (P=.03 and P=.11), while FLIP mRNA expression levels were significantly decreased during rejection (P=.05).

CONCLUSION

Our results indicate that during the IL-2-induced rejection process, infiltrated T cells become more sensitive to apoptosis.

Functional heme oxygenase-1 promoter polymorphism in relation to heart failure and cardiac transplantation

We investigated the functional promoter repeat polymorphism (GT)(n) in the oxidative stress-induced enzyme heme oxygenase-1 in relation to heart failure and complications after transplantation. No influence of the polymorphism on the development of heart failure, graft survival, acute rejection, or transplant atherosclerosis was found.

Noninvasive home telemonitoring for patients with heart failure at high risk of recurrent admission and death: the Trans-European Network-Home-Care Management System (TEN-HMS) study

OBJECTIVES

We sought to identify whether home telemonitoring (HTM) improves outcomes compared with nurse telephone support (NTS) and usual care (UC) for patients with heart failure who are at high risk of hospitalization or death.

BACKGROUND

Heart failure is associated with a high rate of hospitalization and poor prognosis. Telemonitoring could help implement and maintain effective therapy and detect worsening heart failure and its cause promptly to prevent medical crises.

METHODS

Patients with a recent admission for heart failure and left ventricular ejection fraction (LVEF) <40% were assigned randomly to HTM, NTS, or UC in a 2:2:1 ratio. HTM consisted of twice-daily patient self-measurement of weight, blood pressure, heart rate, and rhythm with automated devices linked to a cardiology center. The NTS consisted of specialist nurses who were available to patients by telephone. Primary care physicians delivered UC. The primary end point was days dead or hospitalized with NTS versus HTM at 240 days.

RESULTS

Of 426 patients randomly assigned, 48% were aged >70 years, mean LVEF was 25% (SD, 8) and median plasma N-terminal pro-brain natriuretic peptide was 3,070 pg/ml (interquartile range 1,285 to 6,749 pg/ml). During 240 days of follow-up, 19.5%, 15.9%, and 12.7% of days were lost as the result of death or hospitalization for UC, NTS, and HTM, respectively (no significant difference). The number of admissions and mortality were similar among patients randomly assigned to NTS or HTM, but the mean duration of admissions was reduced by 6 days (95% confidence interval 1 to 11) with HTM. Patients randomly assigned to receive UC had higher one-year mortality (45%) than patients assigned to receive NTS (27%) or HTM (29%) (p = 0.032).

CONCLUSIONS

Further investigation and refinement of the application of HTM are warranted because it may be a valuable role for the management of selected patients with heart failure.

Preferential depletion of blood myeloid dendritic cells during acute cardiac allograft rejection under controlled immunosuppression

Allo-Ag presentation to Ag-specific T-lymphocytes by donor or recipient dendritic cells (DCs) induces acute rejection (AR) after solid organ transplantation. It is postulated that myeloid (mDC) and plasmacytoid (pDC) subsets circulate differentially between bone marrow, heart and lymphoid tissues after cardiac transplantation (HTx). We investigated peripheral blood DC subset distribution, maturation and lymphoid homing properties in relation to endomyocardial biopsy (EMB) rejection grade after clinical HTx. Twenty-one HTx recipients under standard immunosuppression were studied in a 9-month follow-up. mDC and pDC numbers were analyzed by flow cytometry in fresh venous whole blood samples collected during the EMB procedures and before histological diagnosis of AR. Subsets were further characterized for maturation marker CD83 and lymphoid homing chemokine receptor CCR7. Although numbers of both DC subsets remained low for the whole post-HTx period, we observed a negative association of mDCs with rejection grade. Repeated measurements analysis revealed that only mDCs decreased during AR episodes. Rejectors had lower mDC numbers after a 3-month follow-up compared to nonrejectors. Furthermore, patients during AR exhibited low proportions of mDCs positive for CD83 or CCR7. These findings suggest peripheral blood mDC depletion in association with selective lymphoid homing of this subset during AR after clinical HTx.

Population pharmacokinetics of cyclosporine in kidney and heart transplant recipients and the influence of ethnicity and genetic polymorphisms in the MDR-1, CYP3A4, and CYP3A5 genes

OBJECTIVE

Our objective was to determine the relationship between single nucleotide polymorphisms (SNPs) in the multidrug resistance 1 (MDR-1) gene and the cytochrome P450 (CYP) genes CYP3A4 and CYP3A5 and the pharmacokinetics of cyclosporine (INN, ciclosporin).

METHODS

Cyclosporine pharmacokinetics of 151 kidney and heart transplant recipients undergoing maintenance therapy was described by use of nonlinear mixed-effects modeling (NONMEM) according to a 2-compartment pharmacokinetic model with first-order absorption and elimination. All patients were genotyped for the CYP3A4*1B and *3 , CYP3A5*3 and *6 , and MDR-1 3435C-->T SNPs.

RESULTS

For a typical 70-kg white patient, the following parameters were estimated: absorption rate constant, 1.27 h -1; absorption time lag, 0.47 hour; oral volume of distribution of the central and peripheral compartment, 56.3 and 185.0 L, respectively; oral clearance (Cl/F), 30.7 L/h; and oral intercompartmental clearance, 31.7 L/h. Estimated interpatient variability of Cl/F was 28%. Cl/F was significantly correlated with weight and ethnicity; Cl/F was 13% higher (95% confidence interval, 8%-18%; P < .005) in white patients than in black and Asian patients. In carriers of a CYP3A4*1B variant allele, Cl/F was 9% (95% confidence interval, 1%-17%; P < .05) higher compared with CYP3A4*1 homozygotes, and this effect was independent of ethnicity or weight. Incorporation of these covariates into the NONMEM model did not markedly reduce interpatient variability of Cl/F. None of the other SNPs studied significantly influenced any of the pharmacokinetic parameters.

CONCLUSION

Patients carrying a CYP3A4*1B variant allele have a significantly higher oral cyclosporine clearance compared with patients homozygous for CYP3A4*1 . However, this genetic effect on cyclosporine disposition was small, and genotyping of transplant recipients for CYP3A4 is thus unlikely to assist in planning initial cyclosporine dosing.

Intragraft heme oxygenase-1 and coronary artery disease after heart transplantation

Peri-operative tissue injury triggers the development of Transplant Coronary Artery Disease (TCAD). Animal studies have shown that induction of heme oxygenase (HO)-1 protects the donor organ from the development of TCAD. To investigate the role of HO-1 in TCAD after clinical heart transplantation, we measured intragraft mRNA expression of HO-1, HIF-1alpha, TGF-beta, FLIP, and the Bcl-2/Bax balance. Immunohistochemical staining of HO-1 was performed to determine its origin. Myocardial biopsies taken at the end of the transplantation procedure (time 0), at 1 week and at 10 months after transplantation were studied from recipients with or without angiographic signs of accelerated TCAD, diagnosed after 1 year. At time 0, no differences in mRNA expression for any of the measured parameters were found between TCAD positive and negative patients. At 1 week, mRNA expression of HO-1 and TGF-beta was higher in grafts that developed accelerated TCAD (p=0.001 and p=0.0002). These higher mRNA levels were accompanied by a pro-apoptotic shift in Bcl-2/Bax (p=0.02), suggesting proneness for apoptosis via the mitochondrial pathway. Immunohistochemical staining showed that HO-1 was mainly produced by infiltrating macrophages. At 10 months, again HO-1 and TGF-beta levels were high in TCAD positive patients (p=0.02 and p=0.05), but the expression of apoptotic markers was comparable at this time point. Our results suggest that a higher HO-1 by macrophages in our patient population might be an adaptive response to tissue injury and inflammation, reflecting damage due to the transplantation procedure that finally results in TCAD.

The relative importance of cyclosporine exposure in heart, kidney or liver transplant recipients on maintenance therapy

We investigated the relationship between cyclosporine exposure and the presence of cyclosporine-related side effects and assessed the advantage of the cyclosporine concentration 2 h post-dose (C(2)) over pre-dose concentration (C(0)) monitoring. Cyclosporine area-under-the-concentration-time curves were measured during the absorption phase (AUC(0-4 h)) in 49 liver, 28 heart and 26 kidney transplant recipients (time since transplantation >6 years) with or without cyclosporine-related side effects on maintenance therapy. The cyclosporine C(0) correlated well with AUC(0-4) (r=0.77), whereas C(2) levels correlated strongly with AUC(0-4) (r=0.92). Although we observed a trend towards higher CsA concentrations in transplant recipients with side effects than in patients without CsA toxicity, the large majority of those differences were not statistically significant. Thus, as cyclosporine exposure was not clearly related to the presence of side effects, and C(0) correlated fairly with AUC(0-4), the advantage of monitoring cyclosporine treatment using C(2) rather than C(0), may be limited for patients on cyclosporine maintenance therapy.

Ten-year follow-up of recipients of a kidney or heart transplant who received induction therapy with a monoclonal antibody against the interleukin-2 receptor

OBJECTIVES

Twelve years ago, we performed two randomized clinical trials to investigate safety and efficacy of induction therapy with BT563, a highly potent murine monoclonal antibody against the interleukin-2 receptor after kidney and heart transplantation. We analyzed the long-term safety and efficacy data from all 120 patients who participated in the two randomized trials after kidney and heart transplantation 10 years ago.

MATERIALS AND METHODS

One of these two trials was a randomized, double-blind, placebo-controlled trial, with 60 primary and secondary kidney allograft recipients (cadaveric and living-related donors). The control group was treated with the standard regimen at that time, consisting of cyclosporin and prednisone. In the study group, BT563 was added for 10 days. The second trial was a randomized, double-blind trial, with 60 recipients of a primary heart transplant. In that study, we compared induction therapy with BT563 with the standard regimen at that time, consisting of cyclosporin, prednisone, and OKT3 (both induction agents were given for 7 days).

RESULTS

Patient survival in the kidney trial was excellent: in the BT563 group, 24 patients were alive (80%), and in the placebo, group 21 (70%) 10 years after transplantation. Also, graft survival was good: in the BT563 group, 63.3% of the kidneys (19/30) were functioning, in the placebo group, 72.4% (21/29) were functioning (P = 0.455). Also, in the heart study, patient (and graft) survival was excellent: 18 patients were alive in the BT563 group (58%), and in the OKT3 group, 21 (72%) patients were alive (P = ns). No increase in the incidence of malignancies was observed between patients treated with BT563 compared with the control groups. Patients following heart transplantation more often suffered from a malignancy than did patients after kidney transplantation (20/60 vs 10/59).

CONCLUSIONS

We report follow-up data on all patients participating in the two randomized trials, and our data reflect a total of 932 years of patient follow-up. Patient and graft survival appear to be excellent in both the BT563-treated patients and the control groups. BT563 treatment was not associated with an increased likelihood of developing infections or malignancies.

Peripheral blood dendritic cells in human end-stage heart failure and the early post-transplant period: evidence for systemic Th1 immune responses

OBJECTIVES

Dendritic cells (DCs) are antigen presenting cells that play a central role in inflammation, allograft rejection and immune tolerance. Myeloid (mDC) and plasmacytoid (pDC) subsets regulate immune reactions by polarising naive T-helper cells into a Th1 or Th2 response, respectively. In this study we examined total peripheral blood DCs, mDC and pDC subsets in chronic heart failure (CHF) and clinical heart transplantation (HTx).

METHODS

We compared 16 heart transplant patients before and after HTx to 14 healthy controls. Whole blood was collected pre-HTx and 1-week post-HTx from patients and at corresponding time-points from controls. All patients received induction and maintenance immunosuppression post-HTx. mDCs and pDCs were measured by flow cytometry and were further characterised for maturation and homing potential to the secondary lymphoid organs with CD83 and CCR7, respectively. Data were expressed as absolute numbers/microl whole blood, percentage (%) mDC or pDC of total blood DCs and % positive DCs for CD83 and CCR7.

RESULTS

CHF patients had more peripheral blood DCs compared to controls (P<0.01) while only the mDC fraction was increased compared to controls (P=0.01). Percentage CD83(+) and CCR7(+) mDCs was also higher than control levels (P<0.05). One week post-HTx, total DCs, mDCs and pDCs decreased below controls (P<0.001). At the same time % mDCs in peripheral blood increased markedly compared to CHF and control levels (P<0.001). The %CD83(+) mDC, %CD83(+) pDC and %CCR7(+) mDC also returned to control levels and only %CCR7(+) pDC decreased below control levels (P=0.005).

CONCLUSIONS

Total peripheral blood DCs are elevated during CHF due to an increase in the mature fraction of the mDC subset suggesting a possible Th1 response in end-stage heart failure. The decrease in total DCs and mature mDCs and pDCs seen post-HTx, probably reflects immunological quiescence through adequate immunosuppression. Peripheral blood DC monitoring may provide a new insight into mechanisms of heart failure and allograft rejection by safe weaning from immunosuppression after clinical HTx.

Abdominal aortic aneurysms after heart transplantation

BACKGROUND

In recent years abdominal aortic aneurysms were diagnosed in several heart transplant recipients at our center. Only case reports or small series have been reported previously and little is known about abdominal aortic aneurysms after heart transplantation. Therefore, the goals of this study were to estimate the incidence of this condition after heart transplantation, to identify risk factors for its development, and to assess its clinical consequences.

METHODS

Our investigation was a retrospective, single-center cohort study of 368 consecutive patients transplanted between 1984 and 1999.

RESULTS

During a mean follow-up of 75 +/- 49 months, 37 of the 368 (10%) transplant recipients and 36 of 202 (18%) of the sub-group with a history of ischemic heart disease were found to have an abdominal aortic aneurysm. All patients were male, and all except 1 had a history of ischemic heart disease. A history of ischemic heart disease prior to heart transplantation was the sole independent risk factor for developing an aneurysm by multivariate analysis. Aneurysm-related events occurred earlier and more frequently in the 7 transplant recipients who already had a dilated abdominal aorta prior to transplantation. The abdominal aortic aneurysm was the direct or indirect cause of death in at least 9 patients.

CONCLUSIONS

Abdominal aortic aneurysms are relatively frequent after heart transplantation, occur at a younger age than in the general population, and have serious clinical consequences. Close ultrasonographic follow-up of patients with a history of ischemic heart disease or with an abnormal abdominal aorta prior to heart transplantation seems indicated.

Development of the Rotterdam Quality of Life Questionnaire for Heart Transplant Recipients

BACKGROUND

Heart transplantation is a unique and life-threatening event followed by role and lifestyle adjustments, feelings of dependency, and fears about infections and rejection of the donor heart. Generic quality of life measures are unlikely to cover aspects pertinent to transplant recipients. The disease-specific measures available are lengthy and not feasible for use in clinical practice.

AIM

The purpose of the current study was to develop a brief and reliable disease-specific instrument to measure quality of life in heart transplant patients.

STUDY DESIGN

Survey.

METHODS

The Rotterdam Quality of Life Questionnaire for Heart Transplant Recipients was developed according to a series of steps that included in-depth interviews with heart transplant patients, transcription of interviews to form a comprehensive item pool, reduction of the item pool through submission to a panel of healthcare professionals and transplant patients, and further reduction of the item pool through construct formation and statistical analyses. From July to September 2000, all surviving patients (n=237) following heart transplantation at the Erasmus Medical Centre, Rotterdam were asked to fill in the 55-item questionnaire, 205 (86%) of whom replied.

RESULTS

Twelve of the 55 original items were identified as contributing to overall quality of life in heart transplant patients based on four à priori selected constructs. Submission of the 12 items to a factor analysis confirmed that the four-factor structure accounted for 62% of the variance. The reliability of the four subscales was adequate. Mean scores on subscales reflected light to moderate impairment in quality of life.

CONCLUSION

The Rotterdam Quality of Life Questionnaire for Heart Transplant Recipients is a brief disease-specific instrument that measures quality of life in heart transplant patients. Although further studies are required to elaborate on the psychometric properties of the scale, the preliminary reliability of the scale looks promising.

Amiodarone therapy before heart transplantation as a predictor of thyroid dysfunction after transplantation

BACKGROUND

In recent years we have observed new cases of thyroid disease occurring after heart transplantation (HTx). In these patients, the presence of this disease complicates their post-transplant course and occasionally results in life-threatening thyrotoxicosis. The present study examines the incidence and risk factors of thyroid disease in these patients with special emphasis on the use of amiodarone before HTx. Recommendations for follow-up of thyroid disease in HTx patients are discussed.

METHODS

A study was performed on a cohort of 380 patients who received HTx in Rotterdam between January 1, 1985 and April 1, 2001. Twenty patients (5%) developed thyroid dysfunction after HTx, 10 of whom had been treated with amiodarone before HTx.

RESULTS

Cumulative survival curves showed that most patients (60%) developed thyroid dysfunction within the first year after HTx (median interval between HTx and diagnosis was 9 months). Using univariate Cox regression analysis, amiodarone was a significant predictor for the development of thyroid dysfunction (hazards ratio 5.2, 95% confidence interval 2.5 to 10.8). After adjustment for age, gender, heart disease and Quetelet index, amiodarone remained a significant predictor.

CONCLUSIONS

Our study clearly shows that, despite discontinuation of amiodarone treatment at the time of the HTx procedure, patients remain at risk for developing thyroid disease. HTx recipients treated with amiodarone before HTx should therefore be monitored carefully for development of thyroid dysfunction, especially within the first post-transplant year.

Anti-CD25 monoclonal antibody therapy affects the death signals of graft-infiltrating cells after clinical heart transplantation

BACKGROUND

To define whether immunosuppressive agents that block the interleukin (IL)-2 pathway could prevent activation-induced cell death of activated T cells in the graft, we measured expression of IL-2, IL-2 receptor alpha chain (CD25), IL-15, Fas, and Fas ligand by real time reverse transcription-polymerase chain reaction in cardiac allografts.

METHODS

We characterized the phenotype of the infiltrating cells (CD3, CD68, CD25) by immunohistochemistry. The proportion of apoptotic graft-infiltrating cells was determined by TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) staining. We analyzed endomyocardial biopsy specimens from cardiac allograft recipients who were treated with anti-CD25 monoclonal antibody (mAb) induction therapy (daclizumab) or with matching placebo in combination with cyclosporine, steroids, and mycophenolate mofetil.

RESULTS

Treatment with anti-CD25 mAb affected the number of infiltrating CD3 and CD68 cells and the IL-2-regulated apoptotic pathway. During anti-CD25 mAb treatment, significantly lower intragraft IL-2 and CD25 mRNA transcription levels and decreased numbers of CD25+ T cells were found compared with the levels measured in endomyocardial biopsy specimens from placebo-treated patients (5- to 10-fold, P=0.002 and P<0.0001, respectively). In these samples the intragraft mRNA expression levels of IL-15 were also lower (P=0.02). Inhibition of the IL-2 pathway by anti-CD25 mAb therapy was accompanied by reduced mRNA and protein of Fas ligand and not by reduced Fas expression (P=0.001 and P=0.03). TUNEL staining revealed that the proportion of graft-infiltrating cells was lower in the anti-CD25 mAb patient group than the proportion of apoptotic cells in patients receiving placebo (P=0.06).

CONCLUSION

Our data suggest that immunosuppressive agents that affect the IL-2 pathway hinder the mechanism of activation-induced cell death by which the immune system eliminates alloreactive cells.

[Twenty-five years of cyclosporin use in transplantation medicine]

Cyclosporin has greatly improved the short and medium-term outcomes for solid organ transplantation. However, the effect on the long-term outcome has been less impressive. This can partly be attributed to the side effects of cyclosporin, and partly to the fact that the use of cyclosporin has not led to a reduced incidence of chronic allograft nephropathy. Efforts to minimise these side effects have led to the development of the microemulsion form of cyclosporin and improved methods for therapeutic drug monitoring (dosage based on blood levels instead of body weight). Finally, the introduction of new immunosuppressive drugs has made it possible to further reduce the dose of cyclosporin; this might eventually lead to cyclosporin-free immunosuppressive regimens.

Differential intragraft cytokine messenger RNA profiles during rejection and repair of clinical heart transplants. A longitudinal study

After clinical heart transplantation, ischemia, acute rejection, and repair mechanisms can trigger the up-regulation of cytokines. To investigate the cytokine profile early after transplantation, we monitored messenger RNA (mRNA) expression levels of tumor necrosis factor-alpha (TNF-alpha), monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-beta (TGF-beta), platelet-derived growth factor-A (PDGF-A), and basic fibroblast growth factor (bFGF) by reverse transcriptase-polymerase chain reaction (RT-PCR) in serial endomyocardial biopsies ( n=123) from 16 cardiac allograft recipients during the first 3 post-operative months. In the first month, mRNA expression levels of MCP-1, TNF-alpha, TGF-beta, and bFGF were significantly higher than in the period thereafter (acute rejection episodes excluded). Acute rejection (International Society for Heart and Lung Transplantation (ISHLT) rejection grade >2) was strongly associated with the level of TNF-alpha mRNA. After acute rejection episodes, rising mRNA expression levels of PDGF-A and bFGF were found. The association between TNF-alpha mRNA and acute rejection reflects the importance of this cytokine in allogeneic responses. Elevated growth factor expression levels indicate repair responses after tissue damage due to either the transplantation procedure (surgery, ischemia, reperfusion) or acute allograft rejection.

Recipient gene polymorphisms in the Th-1 cytokines IL-2 and IFN-gamma in relation to acute rejection and graft vascular disease after clinical heart transplantation

IL-2 and IFN-gamma are associated with acute rejection (AR) and graft vascular disease (GVD) after clinical heart transplantation. Polymorphisms in the genes of IL-2 (T-330G in the promoter) and IFN-gamma (CA repeat in the first intron) influence the production levels of these cytokines. Therefore, these polymorphisms might have an effect on the outcome after transplantation. To investigate possible effects of genetic variations in IL-2 and IFN-gamma genes on AR and GVD, we analyzed the IL-2 T-330G and the IFN-gamma CA repeat polymorphism in DNA of 301 heart transplant recipients. No associations were found for allele or genotype distributions between patients with or without AR (IL-2 allele frequency: P=0.44, genotype distribution: P=0.46; IFN-gamma allele frequency P=0.10, genotype distribution 12 repeats allele: P=0.21). Also, no associations were found analyzing the number (0 vs. 1 vs. >or=1) of AR (IL-2 allele frequency: P=0.59; genotype distribution: P=0.37; IFN-gamma allele frequency: P=0.27, genotype distribution 12 repeats allele: P=0.41) or analyzing the polymorphisms in patients with AR within the first month or thereafter (IL-2 allele frequency: P=0.45, genotype distribution: P=0.38; IFN-gamma allele frequency: P=0.21, genotype distribution 12 repeats allele: P=0.41). Analyzing both polymorphisms in relation to GVD, resulted in comparable allele and genotype distributions (IL-2 allele frequency: P=0.75; genotype distribution: P=0.77; IFN-gamma allele frequency: P=0.70, genotype distribution 12 repeats allele: P=0.63). In conclusion, we did not detect an association between the IL-2 T-330G promoter polymorphism and CA repeat polymorphism in the first intron of the IFN-gamma gene and AR or GVD after heart transplantation.

Cardiac sarcoidosis: Case-studies and a brief review of the literature

Sarcoidosis is a multi-system granulomatous disorder of unknown aetiology. Symptomatic cardiac involvement occurs in approximately 5% of patients. The prevalence of sarcoidosis in the Netherlands is unknown, but estimated to be approximately 20 per 100,000 population (3200 patients). We report on five patients who presented with different manifestations of cardiac sarcoidosis, and give a brief review on the current management of this condition. Magnetic Resonance Imaging (MRI) can be of great help in diagnosing this condition as well as in the follow-up of the response to therapy.

Effect of HLA-DR matching on acute rejection after clinical heart transplantation might be influenced by an IL-2 gene polymorphism

BACKGROUND

To examine whether genetic factors are involved in the development of acute rejection (AR), we investigated a (CA)m(CT)n repeat in the 3'-flanking region of the interleukin (IL)-2 gene.

METHOD

We genotyped 290 heart transplant recipients with and without AR (International Society for Heart and Lung Transplantation criteria > or =3A) and 101 controls.

RESULTS

The frequency of allele 135 of the repeat and its genotype distribution (carriers/noncarriers) were significantly associated with freedom from AR (P=0.03 and P=0.02, respectively). We also found interaction between allele 135 and HLA-DR matching. More carriers of allele 135 with no or one mismatch remained free from AR compared to patients without the allele (P=0.01). This was not found in the HLA-DR group with two mismatches.

CONCLUSION

HLA-DR matching might only be effective in reducing AR after heart transplantation in recipients who carry allele 135 of the (CA)m(CT)n repeat in the 3'-flanking region of the IL-2 gene.

Prediction of mortality in heart transplant recipients by stress technetium-99m tetrofosmin myocardial perfusion imaging

Cardiac allograft vasculopathy is a major cause of mortality in heart transplant recipients. The aim of this study was to assess the prognostic value of stress myocardial perfusion imaging in heart transplant recipients. We studied 166 patients (age 54 +/- 10 years, 140 men) by symptom-limited bicycle exercise or dobutamine (up to 40 microg/kg/min) stress myocardial perfusion imaging 7.4 +/- 2.5 years after heart transplantation. An intravenous dose of 370 MBq of technetium-99m tetrofosmin was injected at peak stress and 24 hours after the stress test. An abnormal test was defined as reversible or fixed perfusion defects. Perfusion abnormalities were detected in 55 patients (33%). During a median follow-up of 2.5 years, 54 deaths (33%) occurred, 16 of which were due to cardiac causes. The incidence of perfusion abnormalities was higher in patients with subsequent cardiac death than in patients without subsequent cardiac death (69% vs 29%, p = 0.01). In an incremental multivariate Cox analysis, cardiac death was not predicted by age, gender, duration of transplantation, number of rejection episodes, or cytomegalovirus infection. In the next step, stress test parameters were added. The peak rate-pressure product was the only significant predictor at this step (risk ratio 0.84, 95% confidence interval 0.73 to 0.97, chi-square 7.7, p = 0.006). In the final step, the presence of abnormal myocardial perfusion was an independent predictor of cardiac death (risk ratio 3.5, 95% confidence interval 1.6 to 11.7, chi-square 4.7, incremental to clinical and stress test variables, p = 0.01). It is concluded that stress myocardial perfusion imaging with technetium-99m tetrofosmin single-photon emission computed tomography provides incremental data for the prediction of cardiac death in heart transplant recipients.

[The application of electric heart assist devices in 3 patients with end-stage heart failure as a bridge to transplantation]

Left-ventricular assist devices have already gained an international place in the treatment of end-stage heart failure. It is expected that in future they will be increasingly used as a temporary bridging following the recovery from heart failure and to a lesser extent as a bridge to heart transplantation. Three patients with end-stage heart failure, men aged 68, 57 and 49 years, received a left-ventricular assist device (LVAD) as a bridge to transplantation. The device chosen was a Heartmate Vented Electric System (ThermoCardiosystems; Woburn, Massachusetts, US). In this system a pump is implanted under the diaphragm and connected to the apex of the left ventricle and the pars ascendens aortae. The first two patients reached the time of transplantation and used the LVAD for 367 and 416 days respectively. The third patient died after the pump had been implanted, due to progressive right-ventricle failure. The first patient died shortly after the heart transplantation.