A. Zuckermann

Complete revascularization in coronary artery bypass grafting with and without cardiopulmonary bypass.

BACKGROUND The feasibility of complete revascularization on the beating heart without cardiopulmonary bypass (CPB) as compared with the standard operation with CPB in elective low-risk patients with multivessel disease has not been clearly demonstrated in a prospective trial. METHODS Eighty selected low-risk patients were enrolled. In preoperative study with coronary angiography, the decision was made whether complete revascularization without CPB could be performed. Patients were randomly assigned to receive CABG either with (n = 40) or without CPB (n = 40). Randomization criteria were age, sex, and left ventricular ejection fraction. Completeness of revascularization as well as short- and mid-term clinical outcome in a 13.4 +/- 6.5 month follow-up period were monitored. RESULTS Twenty-six of 40 (65%) patients undergoing CABG without CPB underwent complete revascularization. In 5 of these patients (12.5%) suitable vessels were discarded for technical reasons and 9 patients (22.5%) were switched to CABG with CPB owing to the deeply intramyocardial course of target vessels (n = 5) or to hemodynamic instability (n = 4). In the group of patients operated on with CPB, 34 of 40 patients (85%) received complete revascularization. In 6 patients (15%) suitable vessels were discarded for technical reasons. Mean number of bypass grafts was 3.1 +/- 0.8 with CPB and 2.6 +/- 0.5 without CPB (p = 0.043). Clinical outcome and hospital stay were comparable in both groups. No patient died during the study period. No myocardial infarction was observed. Three patients undergoing CABG without CPB underwent successful PTCA 3 months after surgery. CONCLUSIONS CABG without the use of CPB is effective for complete revascularization in the majority of selected low-risk patients. Nevertheless, it has to be stated that the rate of incomplete revascularization in this early series of CABG without CPB is higher, and compromises the basic principle of complete revascularization.

Tacrolimus versus cyclosporine after lung transplantation: a prospective, open, randomized two-center trial comparing two different immunosuppressive protocols

BACKGROUND The need for better immunosuppressive protocols after lung transplantation led us to investigate tacrolimus (Tac) in combination with mycophenolate mofetil (MMF) and steroids or cyclosporine (CsA) in combination with MMF and steroids in a prospective, open, randomized trial after lung transplantation. METHODS Between September 1997 and April 1999, 50 lung transplant recipients were randomized to receive either Tac (n = 26) or CsA (n = 24) in combination with MMF and steroids. All patients underwent induction therapy with rabbit antithymocyte globulin (ATG) for 3 days. Freedom from acute rejection (AR), patient survival, infection episodes, and side effects were monitored. RESULTS There was no difference in patient demographics between the two groups. Six-month and 1-year survival was similar (84.6% and 73.1% in the Tac group vs 83.3% and 79.2% in the CsA group). Freedom from AR at 6 months and 1 year after lung transplantation was slightly higher in the Tac group (57.7% and 50% vs 45.8% and 33.3%, p = not significant [n.s.]), whereas the number of treated rejection episodes per 100 patient days in the Tac group was significantly lower (0.225 vs 0.426, p < .05). Four patients in the CsA group had to be switched to Tac. Two patients in the CsA group had to be retransplanted. Incidence of infections was similar in both groups with a trend toward more fungal infections in the Tac group (n = 7 vs n = 1, p = n.s.). CONCLUSIONS The combination of Tac and MMF seems to have slightly higher immunosuppressive potential compared with CsA and MMF. The effectiveness of Tac as a rescue agent is not paralleled with undue signs of overimmunosuppression.

Comparison between mycophenolate mofetil- and azathioprine-based immunosuppressions in clinical lung transplantation.

BACKGROUND The aim of the study was to assess the impact of mycophenolate mofetil (MMF) on the early phase after lung transplantation. PATIENTS AND METHODS Thirty-eight consecutive patients between November 1994 and January 1997 were treated with cyclosporine, prednisolone, antithymocyte globuline induction therapy, and either MMF (n = 21) or azathioprine (Aza) (n = 17). Four patients from the MMF group and 2 patients from the Aza group were intubated and in the ICU prior to transplantation. Demographic data and primary diagnosis were comparable. MMF was administered at a dosage of 2 gm/day whereas Aza was initiated at 2 mg/kg/day and adapted by leukocyte count. Three-month survival and incidence of rejections and infections were compared. RESULTS Six-month survival in the MMF group was 76% compared to 65% in the Aza group (n.s.). The mean number of acute rejection episodes in the MMF and Aza group were 0.29+/-0.10 and 1.53+/-0.29 (p<0.01) respectively. Transbronchial biopsy (TBB) results > or =grade 2 ISHLT were seen in 10% of MMF and in 43% of Aza-treated patients; completely free from rejection were 17 MMF and 3 Aza patients. The mean number of infections per patient in the MMF and Aza group were 1.57+/-0.29 and 2.29+/-0.40 respectively, bacterial (1.10 vs. 1.71), viral (0.35 vs. 0.33), and fungal (0.14 vs. 0.24) infections were the same in both groups. CONCLUSIONS These data result suggest that mycophenolate mofetil therapy is more effective in preventing rejection episodes in patients early after lung transplantation than therapy with azathioprine. We therefore conclude that MMF is a safe and effective drug to optimize immunosuppressive therapy in the early phase after lung transplantation.

Effect of mycophenolate mofetil therapy on inosine monophosphate dehydrogenase induction in red blood cells of heart transplant recipients

Mycophenolic acid is reported to provide effective immunosuppression by inhibiting inosine monophosphate dehydrogenase. In an attempt to monitor the biological effects of long‐term therapy with mycophenolate mofetil, we measured levels of guanosine 5′ triphosphate and adenosine 5′ triphosphate in red blood cells (RBCs) of patients after heart transplantations.

Effect of mycophenolate mofetil therapy on lymphocyte activation in heart transplant recipients

BACKGROUND Mycophenolic acid is reported to provide effective immunosuppression by inhibiting inosine monophosphate dehydrogenase. In an attempt to monitor the effects of therapy with mycophenolate mofetil, we measured the expression of the activation markers CD25, CD38, CD69 and HLA-DR on lymphocytes of patients after heart transplantation. METHODS Thirty-six patients enrolled in the study were randomly assigned to one of two groups. Patients in the control group (n = 15) received cyclosporine, azathioprine and prednisone. Patients in the study group (n = 21) were switched from azathioprine to mycophenolate mofetil (MMF) 3 months after heart transplantation. The expressions of the activation markers CD25, CD38, CD69 and HLA-DR on B cells, T cells and natural killer (NK) cells in peripheral blood were determined by flow cytometry. RESULTS In patients treated with MMF a significant reduction of the B-cell count was observed in comparison to a healthy control group and patients under therapy with azathioprine. The decline of B cells in the MMF group started 3 months after onset of therapy and, after 1 year, was nearly halved. In addition, the percentages of CD38-positive B cells, activated T cells (CD4(+)/CD25(+), CD8(+)/CD38(+)) and HLA-DR-expressing NK cells were reduced during therapy with MMF. CONCLUSIONS Our studies have shown administration of MMF to be associated with a reduction of B lymphocytes and a downregulation of activation markers on B cells. In contrast to in vitro findings, our data indicate that the immunosuppressive effect of MMF in vivo is exhibited mainly on B cells.

Effects of interleukin-1, -2, -4, -6, interferon-gamma and granulocyte/macrophage colony stimulating factor on human vascular endothelial cells

Human vascular endothelial cells (HUVEC) exhibit various immunological functions, i.e. expression of HLA class-II antigens after incubation with IFN-gamma or antigen presenting function. It has also been reported that HUVEC are able to produce IL-1, IL-6, GM-CSF and immunologically active cleavage products of arachidonic acid. In our study we investigated whether various cytokines, namely IL-1, IL-2, IL-6, GM-CSF and IFN-gamma, do alter the proliferative capacity of HUVEC, the production of van Willebrandt factor (vWF) and the expression of MHC class-II antigens. HUVEC were prepared by the collagenase digestion of human umbilical veins. Monolayers of cells were incubated with cytokines in different concentrations for 24 and 48 h. IFN-gamma inhibits the HUVEC [3H]thymidine uptake in a dose-dependent manner. Suppression of proliferation (40.1%) could be observed after 24 h incubation with 100 U IFN-gamma/ml. IL-1 was a more effective inhibitor of HUVEC proliferation (54% at 10 U/ml and 24 h incubation and 48.4% after 48 h) than IFN-gamma. IL-6 and GM-CSF showed an increasing effect on proliferation with 226% and 151% of the control group, respectively. IFN-gamma after an incubation period of 12 h and IL-1 after 24 h reduced the vWF content by about 30%. Bright MHC class-II expression was induced only by IFN-gamma. In conclusion, some of the immunoregulative cytokines might play an important role in the control of HUVEC proliferation.

Phenotypic Patterns of Mononuclear Cells in Dilated Cardiomyopathy

BACKGROUND Immunological factors in the pathogenesis of idiopathic dilated cardiomyopathy (IDC) were suggested previously on the basis of the demonstration of mononuclear cell infiltrates and autoantibodies against the myocardium. The present study investigated whether tissue leukocyte subpopulations isolated from hearts with IDC (n = 6) differ in phenotype from those of tissues without IDC (n = 7). METHODS AND RESULTS Leukocytes were quantified as reactive cells per square millimeter in perivascular, interstitial, and parenchymal tissue sections. Freshly isolated heart-tissue T cells and peripheral-blood T cells from the same patients were analyzed by triple staining and flow cytometry to identify T-cell subpopulations as well as their states of differentiation (expression of CD45RA and Leu-8 versus CD45RO) and activation (IL-2R, IL-7R, very late antigen-1, HLA-DR). All types of infiltrating cells (T cells, B cells, macrophages, granulocytes) are increased in hearts with IDC compared with normal hearts, but only CD8+ T cells and macrophages are increased relative to the other leukocyte subpopulations. CD45RO+/CD45RA-/Leu-8- cells constitute the majority of heart-tissue T cells in both normal hearts and hearts with IDC. Strikingly, hearts with IDC are infiltrated by eightfold greater numbers of perivascularly located IL-2R(+)- (26% of all T cells) and CD45RO(+)-activated memory T cells; moreover, in contrast to normal heart, approximately 40% of both CD4+ and CD8+ heart-tissue T cells express activation markers. CONCLUSIONS Both normal hearts and hearts with IDC are populated by leukocytes. The quantitative increase in IDC, associated with a dramatically altered activation status of heart-tissue T cells, suggests a direct role of infiltrating leukocytes in the pathogenesis of IDC.

Long-term survival (>10 years) of patients >60 years with induction therapy after cardiac transplantation.

OBJECTIVE Cardiac transplantation has become an established method for end-stage heart disease. Short- and mid-term outcome has been known to be similar between younger and older (>60 years) recipients. So far, nothing is known about long-term outcome of old patients and the potential long-term effects of antibody induction therapy in these patients. The purpose of this study was to analyse long-term outcome of old cardiac transplant recipients who underwent antibody induction therapy. METHODS Since 1989, 203 patients (total n = 882) above 60 years have been transplanted at our center. On these patients n = 66 were above 65 years. Survival, incidences of rejection, infection, cancer, graft arteriosclerosis and the amount of renal insufficiency were compared with patients <60 years (n = 679), transplanted during the same period of time. Freedom from specific event was computed by Kaplan-Meier analysis and compared by log-rank test. RESULTS Ten year survival was similar in all groups (<60 years: 53.7%; 60-64 years: 53.1% and >65 years: 60.2%; P = NS). Causes of death were similar in all patient groups. There were significant fewer rejection episodes in the older patient group (freedom from rejection: 74.9 vs. 83.5 vs. 90.6; P = 0.03). Yet significantly more number of patients >65 years were without steroid maintenance therapy (43.1%) compared to other patient groups (8.2 vs. 9.3%; P < 0.05). There was no difference in overall freedom from severe infection (74.1 vs. 67.7 vs. 85.3%; P = NS), whereas there was a trend towards more CMV disease in the oldest patient group (82.7 vs. 88.6 vs. 70.8%; P=0.06). The incidence of cancer was similar in all groups (freedom from cancer: 82.2 vs. 84.7 vs. 79.1%; P = NS), as well as there was no difference in severe graftsclerosis between all patients (79.2 vs. 93.7 vs. 93.3%; P = NS). There was no difference in development of chronic renal dysfunction (creatinine > 2.0 mg/dl) between the three groups (10 vs. 14 vs. 16%; P = NS). CONCLUSIONS Old recipients of cardiac transplants have a similar long-term outcome than younger recipients. They were less prone to rejections, had a similar incidence of severe infections and showed a trend towards more CMV disease. All patients had a very low rate of graft arteriosclerosis that was similar amongst the groups. Age-related decline of the immune system further enhanced by immunomodulation of antibody induction therapy might be accounted for the results as well as steroid-free immunosuppression.

Long-term results of CMV hyperimmune globulin prophylaxis in 377 heart transplant recipients

BACKGROUND Cytomegalovirus (CMV) has emerged as the most important pathogen to affect the post-operative course after heart transplantation. We performed a retrospective analysis to evaluate the efficiency of CMV hyperimmune globulin (CMVIG) prophylaxis in preventing CMV disease in aggressively immunosuppressed patients after heart transplantation. METHODS We studied 377 heart transplant recipients who received quadruple-immunosuppressive therapy and CMVIG as sole CMV prophylaxis. The study population was categorized into 4 groups according to donor and recipient CMV serology at the time of transplantation (D+/R+, D+/R-, D-/R+, D-/R-) and was monitored for CMV immediate early antigen in peripheral blood cells, in urine sediments, and in throat washings; for the presence of serum CMV immunoglobulin M and CMV immunoglobulin G; and for clinical evidence of CMV-related symptoms. In addition, we compared the incidence of cardiac allograft vasculopathy and infection among the groups. RESULTS During the first 5 years after transplantation, CMV disease developed in 79 patients (20.96%). Comparison among the groups showed significantly increased risk for CMV disease in allograft recipients of organs from seropositive donors (D+, 27.31%; D-, 11.33%; p = 0.0003). We observed 6 CMV-associated deaths, all in CMV-antibody-negative recipients. Additionally CMV-positive recipients had a greater incidence of cardiac allograft vasculopathy (p = 0.048), and a greater overall infection rate (p = 0.0034). CONCLUSIONS Cytomegalovirus hyperimmune globulin administration prevents CMV disease and infection in aggressively immunosuppressed heart transplant recipients. Because fatal CMV disease in CMV-negative recipients of organs from seropositive donors could not be prevented with CMVIG alone, we recommend the additional use of prophylactic ganciclovir in this CMV-mismatched population.

Treatment of non-healing skin ulcers with autologous activated mononuclear cells

The aim of this study was to investigate whether cultured autologous mononuclear cells (MNC) effectively initiate, accelerate and improve granulation and epithelialisation of skin ulcers. Thirty-three patients with chronic arterial occlusive disease (CAOD; n = 21) or venous post-thrombotic syndrome (PTS; n = 12) were treated with autologous MNC and compared with a control group of 30 patients who received tissue culture medium alone. Previous treatments had been unsuccessful for a mean of 9.23 (3-19) months. MNC were harvested from the peripheral blood of each patient by standard techniques, cultured for three days and applied to the ulcer twice a week. After 4.6 +/- 1.9 weeks, 29/33 ulcers were closed in the MNC group. Patients in the control group took 8.1 +/- 1.2 weeks for 17/30 ulcers. Thus ulcer healing was significantly speedier with MNC seeding; 48% of all ulcers were closed after 30 days of MNC treatment and 92% after 60 days. Patients with PTS responded significantly faster than patients with CAOD. In 90% of patients with painful ulcers MNC treatment resulted in pain relief, whereas in the control group only 50% of patients became pain-free.