Endocardial infiltrates in the transplanted heart: clinical significance emerging from the analysis of 5026 endomyocardial biopsy specimens.

UNLABELLED: To further elucidate the significance of endocardial infiltrates in heart transplant patients, the presence, frequency, and type of endocardial infiltrates were evaluated in 5026 endomyocardial biopsy specimens obtained from 200 heart transplant patients 0 to 75 months after heart transplantation. The relationship of endocardial infiltrates to immunologic, clinical, and demographic variables was then explored. Endocardial infiltrates were detected in 557 endomyocardial biopsy specimens (11%) from 117 heart transplant patients (58%) at 6.3 +/- 9.4 months (mean +/- SD; range, 0 to 49 months) after heart transplantation. Heart transplant patients with endocardial infiltrates were younger (p = 0.03), had a greater incidence of idiopathic dilated cardiomyopathy before heart transplantation (p = 0.05), and included a greater percentage of females (p < 0.05). Both total and treated rejection rates were significantly higher in patients with endocardial infiltrates versus those without endocardial infiltrates (p = 0.0001). Rejection on the subsequent endomyocardial biopsies was more often present in endocardial biopsy specimens with endocardial infiltrates than in those without endocardial infiltrates, both in the presence (37% versus 24%; p < 0.001) and absence (33% versus 19%; p < 0.0001) of concomitant findings of rejection. No association was identified between endocardial infiltrates and posttransplantation lymphoproliferative disorder, cytomegalovirus infection, Epstein-Barr virus infection, or cardiac allograft vasculopathy. Multivariate regression analysis confirmed that the occurrence of endocardial infiltrates is associated with rejection when adjustment is made for patient's age, gender, heart disease before transplantation, follow-up time, and number of endomyocardial biopsies after heart transplantation (p = 0.0001). CONCLUSIONS: (1) Endocardial infiltrates may occur with or without associated endomyocardial biopsy findings of rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

HLA-DR incompatibility predicts heart transplant rejection independent of immunosuppressive prophylaxis.

To determine whether immunosuppressive prophylaxis reduces the effect of HLA-DR incompatibility on rejection, we compared clinical and immunologic variables of patients given horse antithymocyte globulin, OKT3, or no immunosuppressive prophylaxis. Median follow-up was 27 months. Groups were similar in race; preoperative HLA reactivity; ABO matching; number of HLA-A, -B, -C, and -DR mismatches; and rejection severity. Patients given immunosuppressive prophylaxis were younger (p = 0.04), had a greater frequency of preoperative ischemic disease (p = 0.03), and had a higher 6-month rejection rate (p = 0.02). A highly significant association was found between the number of mismatches at the HLA-DR locus and rejection severity (p = 0.005). Within the OKT3-based immunosuppressive prophylaxis group and the no immunosuppressive prophylaxis group a significant association was found between the number of HLA-DR mismatches and rejection severity (p = 0.01 and p = 0.009, respectively). A similar trend was identified in the group given horse antithymocyte globulin-based immunosuppressive prophylaxis. Logistic regression, used to identify independent predictors of rejection, showed that the number of HLA-DR mismatches and not the use or type of immunosuppressive prophylaxis is significantly associated with rejection (p = 0.0009). One-year patient survival was 83% in the group with two HLA-DR mismatches and 85% in the group with one or no HLA-DR mismatch. Thus the lower rejection rates in patients with one or no HLA-DR mismatch were not associated with a 1-year survival, which was better than that of patients with two HLA-DR mismatches. The potential benefit of HLA-DR matching on rejection and patient survival must be confirmed by larger prospective studies.

Heart transplantation as a treatment option for end-stage heart disease in patients older than 65 years of age.

Because of the critical donor organ shortage for heart transplantation, selection of recipients should be based on the potential for maximum benefit. To evaluate the effects of advancing age on outcome after heart transplantation, we compared the clinical variables of 12 recipients aged 65 years or older (66.1 +/- 0.9 years [x +/- standard deviation]; range, 65 to 67 years) with those of 57 patients aged 55 to 64 years (59.3 +/- 2.7 years) at the time of the procedure. The two study groups were similar in sex, race, pretransplantation heart disease, immunocompatibility, maintenance immunosuppression, and length of first hospitalization at the time of the procedure. Groups were also similar regarding the incidence of malignancies, fractures, diabetes, neurologic complications, and renal dysfunction occurring over the follow-up period. Patients 65 years of age or older had a significantly higher number of hospital days (36 +/- 29 versus 15 +/- 18 days; p < 0.02) and increased frequency of infections/month (0.7 +/- 0.3 versus 0.3 +/- 0.4 infections/month; p < 0.03) during the first postoperative year. Older patients had a higher incidence of cytomegalovirus infections (50% versus 19%; p < 0.06), lower rates of rejection at 1 and 6 months after operation (p < 0.03), and more severe functional limitation (p < 0.002) than patients aged 55 to 64 years. One-year actuarial survival was not significantly different in the two groups. The results of our study suggest that, because of lower rejection and higher infection rates, heart transplantation recipients older than 65 years of age should receive less intense immunosuppression.(ABSTRACT TRUNCATED AT 250 WORDS)

Pretransplantation risk factors for death after heart transplantation: a multiinstitutional study. The Transplant Cardiologists Research Database Group.

Risk factors for death after heart transplantation were identified by analyzing the total primary heart transplantation experience (n = 911) among 25 institutions from January 1, 1990, through June 30, 1991. Overall actuarial survival was 93% at 1 month and 84% at 12 months. The hazard function for death was highest early after heart transplantation and fell rapidly over the first 6 months, with a gradually declining hazard thereafter. The two most common causes of death were infection (n = 29) and early graft failure (n = 28), accounting for 45% of the overall deaths. By multivariable analysis, risk factors for death during the study period included very young recipient age (p = 0.004), advanced age (p = 0.009), ventilator support at time of transplantation (p = 0.09), abnormal renal function (p = 0.1), lower pretransplantation cardiac output (p = 0.009), higher pulmonary vascular resistance in children (p = 0.006), longer donor ischemic time (p = 0.001), older donor age (p = 0.001), and donor and recipient not both blood type O (p = 0.009). The recipient age effect was greatest in patients under 5 years of age (1-year survival rate 68% versus 85% for all others, p = 0.002). Patients aged 60 years and older had a 1-year survival rate of 81%. Patients who were ventilator dependent at transplantation fared especially poorly, with a 3-month survival rate of 65%. Transplantation of a blood group O heart into a non-O recipient had a somewhat lower 1-year survival rate than did blood group O into an O recipient (82% versus 88%, p = 0.06). The adverse effect of a longer ischemic time was most notable after 4 hours (1-month survival rate 71% for more than 4 hours versus 85% for less than 4 hours, p = 0.0003). Inference: These multiinstitutional-derived risk factors for early-term death after heart transplantation may help improve patient and donor selection and focus further scientific investigations to increase the safety of heart transplantation.

High-risk cardiac operation: a viable alternative to heart transplantation.

To determine if high-risk heart operation with circulatory support standby is an acceptable alternative to direct heart transplantation, we reviewed 21 patients who were accepted as heart transplant candidates but offered a heart operation because of the availability of circulatory support. Preoperative left ventricular ejection fraction was 0.25 +/- 0.08 (mean +/- standard deviation), and New York Heart Association functional class was 3.4 +/- 0.7. The patients underwent 16 bypass graft operations, 4 mitral and 2 aortic valve replacements, and 4 defibrillator implantations (combined procedures in 5 patients). An intraaortic balloon pump was placed in 12 patients. One patient required biventricular assist device support but was weaned in 11 days. Twenty patients were discharged 14.8 +/- 11.5 days postoperatively. One patient died 15 days postoperatively of amiodarone-induced respiratory failure, and 1 died suddenly 2 months postoperatively. At 10.5 +/- 6 months postoperatively, 19 patients (90%) are alive. Mean functional class is 1.9 +/- 0.9. None of the patients has undergone transplantation, but 2 are awaiting donor organs. We conclude that in selected heart transplant candidates high-risk heart operation is a viable alternative to direct heart transplantation.

Role of humoral immunity in acute cardiac allograft dysfunction.

To elucidate the pathogenic mechanisms of acute allograft dysfunction that is not caused by acute cellular rejection, we have studied the clinical and immunopathologic characteristics of 11 heart transplant recipients who had acute allograft dysfunction in the absence of interstitial mononuclear cell infiltrates on endomyocardial biopsy samples. Six of eleven patients (54%) had a striking increase in levels of anti-HLA antibodies in close temporal proximity with the episode of acute allograft dysfunction. Cardiac allograft function improved in all patients with intensification of immunosuppression.

Gastrointestinal complications and endoscopic findings in heart transplant patients.

To determine the scope of gastrointestinal complications in heart transplant recipients, we examined the frequency and nature of gastrointestinal complications by reviewing the indications and findings of endoscopic and surgical procedures involving the gastrointestinal tract in 159 patients. All patients were treated with prednisone, azathioprine, and cyclosporine after transplantation. Sixty-seven patients (42%) had gastrointestinal symptoms significant enough to warrant either endoscopic, radiologic, or surgical procedures. Forty-seven patients (30%) underwent esophagogastroduodenoscopy or upper gastrointestinal roentgenography with a high frequency of esophagitis, gastritis, duodenitis, and gastroduodenal ulcers. Thirty-two patients (20%) underwent barium enema or endoscopic procedures of the lower gastrointestinal tract, with the most frequent findings being benign polyps and colitis. Opportunistic infections, especially with cytomegalovirus, were frequent and were only diagnosed by endoscopic procedures, indicating an advantage of endoscopy over barium studies in these patients. Twenty-three patients (15%) underwent surgical procedures for gastrointestinal complications with 2.5% mortality. Hence, significant gastrointestinal complications that are common in heart transplant recipients, can be safely managed surgically when surgical intervention is indicated.

Risk/benefit ratio of perioperative OKT3 in cardiac transplantation.

This study shows that perioperative OKT3 provides no benefit in terms of the time of onset or frequency of rejection or patient survival. However, it does result in an increased incidence of infection, particularly CMV infection. Thus, the risk/benefit ratio of perioperative OKT3 does not appear favorable. However, a multicenter, randomized trial including a larger number of patients and longer patient follow-up will be required to definitively answer the question.

Endomyocardial biopsy findings after photopheresis treatment of cardiac transplant rejection.

Photopheresis is a potential therapy for allograft rejection in which reinfusion of mononuclear cells exposed to ultraviolet-A irradiation after pretreatment with 8-methoxypsoralen may initiate immunosuppressive responses. Endomyocardial biopsies (EMBs) of cardiac transplant recipients with moderate acute rejection (IHSLT grades 2 and 3) treated with photopheresis (7 patients/9 treatments) and followed for six months or more were evaluated and compared with biopsies of patients treated with corticosteroids (7 patients/8 treatments) and followed for a similar time period. The first posttreatment EMB showed improvement in 100% of corticosteroid-treated patients, compared with 56% of photopheresis-treated patients (p < 0.005). Interstitial infiltrates of >90% T-lymphocytes were present in a greater percentage of photopheresis-treated patients than in corticosteroid-treated patients on the first five posttreatment EMBs (p < 0.005) as follows: EMB 1, 90% vs. 25%; EMB 2, 90% vs. 25%; EMB 3, 78% vs. 0%; EMB 4, 56% vs. 0%, EMB 5, 56% vs. 0%. Postphotopheresis EMBs also showed giant cell reaction in 1 patient and extensive band-like infiltrates in 3 patients. Our results suggest that interstitial T-cell infiltrates are more prevalent and persist longer after photopheresis than after corticosteroid treatment of heart allograft rejection. Whether these T-lymphocytes are alloreactive or mediate immunosuppressive signals is unknown. The use of new immunosuppressive therapies may modify endomyocardial biopsy findings, requiring adjustment of the diagnostic criteria for assessing and grading allograft rejection.

Photopheresis versus corticosteroids in the therapy of heart transplant rejection. Preliminary clinical report.

BACKGROUND: Photopheresis is a technique in which reinfusion of mononuclear cells exposed to UV-A light ex vivo after in vivo treatment with 8-methoxypsoralen initiates host-immunosuppressive responses. METHODS AND RESULTS: To determine if photopheresis safely reverses International Society for Heart and Lung Transplantation (ISHLT) rejection grades 2, 3A, and 3B without hemodynamic compromise, 16 heart transplant patients with ISHLT rejection grades 2, 3A, and 3B were randomized to photopheresis or corticosteroid therapy. The average number of mononuclear cells treated with each photopheresis procedure was 9.8 +/- 9.1 x 10(9) (mean +/- SD). Photopheresis and corticosteroids reversed eight of nine and seven of seven episodes of rejection, respectively. The median time from initiation of treatment to rejection reversal was 25 days (range, 6-67 days) in the photopheresis group and 17 days (range, 8-33 days) in the corticosteroid group. Hemodynamics were normal before either treatment and did not change after reversal of rejection. No adverse reactions occurred with photopheresis, and all patients in either treatment group are alive. CONCLUSIONS: These preliminary, short-term results in prospectively randomized patients indicate that photopheresis may be as effective as corticosteroids for treating ISHLT rejection grades 2, 3A, and 3B. The apparently low toxicity and potential efficacy of photopheresis warrant further analysis of its role in the prevention and treatment of heart transplant rejection.

Cytomegalovirus infections in heart transplant recipients: relationship to immunosuppression.

To determine the relationship of cytomegalovirus infections (CMVI) to immunosuppression in heart transplants, we retrospectively compared demographic and clinical variables in 154 consecutive heart transplant patients. Forty-one CMVI were compared; of these, 30 (73%) were identified in tissue, and nine (22%) were identified by blood or urine culture. Twenty (49%) of the CMVI were self-limited, and 21 (51%) were progressive, requiring treatment. When comparing patients with and without CMVI, demographic variables, mean preexisting heart disease, cyclosporine level, cumulative corticosteroid dose, and the use of anti-T-cell antibodies were examined. Only the use of OKT3 was significantly associated with the subsequent development of CMVI. Although CMVI subsequently developed in 30 of 79 (38%) patients who had received OKT3, CMVI developed in only 11 of 75 (15%) patients who had not received OKT3 (p = 0.01). Furthermore, the incidence of CMVI increased with increasing total OKT3 dose (none, 11 of 64 [17%]; < or = 75 mg, 23 of 66 [35%]; > 75 mg, 6 of 14 [43%]; p = 0.01). Logistic regression showed that the only two variables predictive of CMVI were the use of OKT3 (p = 0.0023) and ischemic rather than idiopathic heart disease before transplantation (p = 0.0098). Rejection rates, incidence of allograft vasculopathy, and 1-year actuarial survival were not influenced by previous CMVI. Pneumocystis carinii pneumonia occurred more frequently in patients with CMVI than in those without (13 of 41 [32%] patients versus 3/113 [3%] patients; p < 0.001). No correlation existed between CMVI and lymphoproliferative disorder (p = 0.84).(ABSTRACT TRUNCATED AT 250 WORDS)

Cytomegalovirus and other herpesviruses: do they have a role in the development of accelerated coronary arterial disease in human heart allografts?

In conclusion, a great deal of indirect and inferential data point to herpesviruses as having a role in atherogenesis. It has been shown that the herpesviruses are able to remain within vascular tissue in a latent state, allowing for reactivation to occur with subsequent sequelae of an active infection. Herpesviruses affect the cellular metabolic activity of cells, induce the accumulation of lipids, and inhibit the production of matrix proteins. They have the ability to inhibit endothelial cell binding to the basement membrane. It is also known that the herpesviruses, particularly CMV, can initiate a variety of immunologic responses that may contribute to endothelial damage, precipitating atherogenesis. We are only beginning to understand how CMV may participate in ACAD. Greater attention must be focused on the exact cause-and-effect relationship between CMV infection and ACAD. Even the presence of CMV genomes in arterial walls of allografts must be viewed conservatively in the knowledge of CMV ubiquity and other probable contributions to ACAD. If CMV is involved in the development of ACAD, as an active or latent infection, directly or indirectly, it probably involves numerous coexistent mechanisms (Figure 5).

Cardiac allograft vasculopathy: relationship with acute cellular rejection and histocompatibility.

This article reviews the literature and summarizes the data obtained at Loyola University of Chicago about the relationship between rejection, histocompatibility, and cardiac allograft vasculopathy. Both the studies concerning the relationship between rejection and cardiac allograft vasculopathy and those evaluating the impact of histocompatibility on cardiac allograft vasculopathy have produced conflicting results. Most studies are retrospective and include a small number of patients followed up for short periods of time and treated with variable immunosuppressive regimens. In addition, the diagnosis of cardiac allograft vasculopathy is based on angiographic detection of coronary arterial abnormalities, a method that is known to underestimate the presence and severity of cardiac allograft vasculopathy. The ability to assess the impact of histocompatibility on the development of cardiac allograft vasculopathy is also limited by the lack of uniformity in the type and number of HLA variables analyzed, the extreme polymorphism of the HLA antigens and variability in serologic tissue typing techniques and quality. The results of our study suggest that complete mismatch at the HLA-B and -DR loci is associated with higher rejection rates and severity and with increased mortality. We also noted a trend toward a higher incidence of cardiac allograft vasculopathy in patients with complete mismatch at the HLA-DR locus. Future experimental and clinical studies should be done with use of molecular tissue typing techniques to further elucidate the impact of histocompatibility on cardiac allograft vasculopathy. The role of non-HLA antigens in the development of cardiac allograft vasculopathy requires further definition. Because in heart transplantation the short donor ischemic times compatible with a successful outcome limit the feasibility of prospective donor/recipient tissue typing, the development of immunosuppressive drugs that effectively reduce the detrimental effects of tissue incompatibility is crucially needed.

Successful treatment of heart transplant rejection with photopheresis.

Photopheresis is a potential therapy for rejection in which reinfusion of mononuclear cells exposed to ultraviolet-A light ex vivo, after treatment with 8-methoxypsoralen in vivo, initiates host immune responses that specifically inhibit the cytotoxicity of the photomodulated mononuclear cells. Between May 1990 and January 1991, 7 heart transplant (HT) patients (age 42.2 +/- 16.7 [mean +/- SD] years) on triple immunosuppression (cyclosporine, corticosteroids, and azathioprine) had 9 episodes of non-hemodynamically compromising moderate rejection that were treated with photopheresis. These episodes of rejection occurred at an average of 114.4 +/- 180.5 (range 8-575) days after HT. After oral administration the mean serum level of 8-methoxypsoralen achieved was 129.0 +/- 72.4 ng/ml. An average of 10.4 +/- 9.6 x 10(9) mononuclear cells were treated with each photopheresis procedure. Photopheresis was performed twice when less than 5 x 10(9) mononuclear cells had been treated with the first procedure. Of 9 rejection episodes treated with photopheresis, 5 required 1 procedure and 4 required 2 procedures. Photopheresis was used to treat a single episode of rejection in 5 pts. and 2 separate rejection episodes in 2 additional pts. Eight of 9 episodes of rejection were successfully reversed by photopheresis as assessed by endomyocardial biopsy (EMB) performed 7 days after treatment. Immunohistochemical analysis of EMB samples revealed that postphotopheresis cell counts for T cells, B cells, and macrophages were reduced compared to pretreatment values and correlated with the histopathologic resolution of rejection. Hemodynamics were normal prephotopheresis and remained unchanged at the time when the postphotopheresis EMB showed no evidence rejection No adverse effects have been observed with photopheresis. Over a follow-up period of 5.3 +/- 4.0 months, rejection and infection rates/pt./follow-up months were 0.3 +/- 0.4 and 0.04 +/- 0.07, respectively. The preliminary, short term results of this pilot study indicate that photopheresis may be efficacious in the treatment of moderate rejection in hemodynamically stable HT patients and thus may be an alternative to corticosteroid pulses.

Comparison of results after heart transplantation: mechanically supported versus nonsupported patients.

Between March 1984 and July 1990 our team transplanted 168 hearts. One hundred twelve patients did not require mechanical support (group I). Fifty-six patients required mechanical support (group II). Intraaortic balloon counterpulsation was used in 37 patients (66%). The total artificial heart (TAH) was used in 16 patients (29%), and the ventricular assist device (VAD) was used in three patients (5%). The time spent on the device ranged from 1 to 35 days. No statistical difference was noted on the survival between the two groups. The 30-day and 1-year survival rate was 95% (106 patients) and 71% (79 patients) in group I and 91% (51 patients) and 68% (38 patients) in group II. As of July 31, 1990, 70% in group I and 68% in group II are alive. No significant differences were found between the two groups for the following variables (after heart transplantation): length of stay, 30-day survival, 1-year survival, and complications. The only significant difference found between the two groups was the incidence of infections: group I, 23%; group II, 51.7% (p = 0.001). Mechanical support as a bridge to transplantation provides excellent support until a donor becomes available. No difference was found in the 30-day and 1-year survival between the two groups.