Improved results after heart-lung transplantation: a 17-year experience

Immunosuppression considerations in simultaneous organ transplant

Solid organ transplantation is a life-saving procedure for patients in the end stage of heart, lung, kidney, and liver failure. For patients with more than one failing organ, simultaneous organ transplantation has emerged as a viable treatment option. Immunosuppression strategies and outcomes for simultaneous organ transplant recipients have been reported, but often involve limited populations. Transplanting dual organs poses challenges in terms of balancing immunosuppression with immunologic risk and allograft damage from surgical complications. Furthermore, transplanting certain organs can impose considerations on the management of immunosuppression. For example, liver allografts may confer immunologic privilege and lower rates of rejection of other allografts. This review article evaluates immunosuppression strategies for simultaneous kidney-pancreas, liver-kidney, heart-kidney, heart-liver, heart-lung, lung-liver, and lung-kidney transplants. To date, no comprehensive review exists to address immunosuppressive strategies in simultaneous organ transplant populations. Our review summarizes the available literature and provides evidence-based recommendations regarding immunosuppression strategies in simultaneous organ transplant recipients.

Combined Heart Lung Transplantation: An Updated Review of the Current Literature

Heart lung transplantation is a viable treatment option for patients with many end-stage heart and lung pathologies. However, given the complex nature of the procedure, it is imperative that patients are selected appropriately, and the clinician is aware of the many unique aspects in management of this population. This review seeks to describe updated organ selection policies, perioperative and postoperative management strategies, monitoring of graft function, and clinical outcomes for patients after combined heart-lung transplantation in the current era.

Impact of congenital heart disease on outcomes of pediatric heart-lung transplantation

HLT is reserved for children with cardiopulmonary disease not amendable to alternative therapies. Children with CHD with or without ES may be considered for HLT. Outcomes of HLT in this population are not well described. To test the hypothesis that CHD without ES is associated with worse graft survival and identify factors associated with poor outcome, a retrospective analysis of the UNOS database was performed. One hundred and seventy-eight pediatric HLTs were performed between 1987 and 2011. CHD was the diagnosis in 65 patients, of which 34 had CHD without ES. Patients with CHD without ES had decreased patient survival (median 1.31 yr) compared with CHD with ES (4.80 yr, p = 0.05). On multivariable analysis, the following were associated with graft failure: CHD without ES (adjusted HR 1.69, 95% CI 1.09-2.62), younger age (1.04, 1.01-1.08), pretransplant mechanical ventilation (1.75, 1.01-3.06), pretransplant ECMO (3.07, 1.32-7.12), pretransplant PRAs (1.53, 1.06-2.20), and transplant era (1.85, 1.16-2.94). In children with CHD who require HLT, underlying physiology influences outcomes. Those without ES have a worse prognosis. The diagnosis of CHD without ES and preoperative factors may inform decisions in a complex patient population.

Heart-lung transplantation in patients with pulmonary atresia and ventricular septal defect

OBJECTIVE

Heart-lung transplantation for patients with pulmonary atresia and ventricular septal defect is challenging. The aim of the study was to present a single-center experience with heart-lung transplantation in this difficult group of patients.

METHODS

A retrospective review identified 9 patients aged 4.1 to 45.6 years (median, 25.4 years) with pulmonary atresia and ventricular septal defect who underwent heart-lung transplantation. Four (44.4%) patients had previous heart operations: 3 of them had palliative procedures (systemic-to-pulmonary shunts), and 1 had multistage correction. A standard transplantation method was used, with the exception of 1 patient with heterotaxy syndrome who underwent a modified operation. Major aortopulmonary collateral arteries were controlled by using various techniques.

RESULTS

Follow-up ranged between 2 days and 12.6 years (median, 1.2 years). The hospital mortality rate was 22.2% (n = 2). In the late postoperative period, 3 patients died. The survival curve was similar to that of patients with other diagnoses undergoing heart-lung transplantation. The median length of intensive care unit stay was 58 days (range, 22-82 days), and the median length of hospital stay was 83 days (range, 35-136 days). The most common early complication was bleeding requiring re-exploration. In all cases the bleeding was proved to be from collateral vessels.

CONCLUSIONS

Heart-lung transplantation in patients with pulmonary atresia and ventricular septal defect requires carefully planned and meticulously performed surgical intervention. This management should be taken into consideration as a future option if the specific anatomy is uncorrectable in early childhood, and the palliative procedures should be avoided.

Estudio comparativo de dos soluciones de preservación en la función inicial del trasplante bipulmonar en humanos

OBJECTIVE

Compare the influence of two preservation liquids, Euro-Collins (EC) and Perfadex (P) in the pulmonary graft function in the initial phase of lung transplant in humans.

DESIGN

Retrospective study.

SCOPE

Lung transplant unit of the ICU of a university hospital.

PATIENTS

A total of 79 patients were subjected to a transplant of both lungs. The pulmonary grafts were preserved with EC in 23 cases and with P in 56 cases.

VARIABLES OF INTEREST

Pulmonary function was assessed on admission in the intensive care unit (ICU) with the PaO2/FiO2 ratio. Mortality, graft dysfunction stay in ICU and time of mechanical ventilation were also assessed at 30 days.

RESULTS

The PaO2/FiO2 ratio was significantly greater in the P group than in the EC both on admission (p<0.006) and at 12 hours (p=0.032) in the ICU. Graft dysfunction incidence was less in group P than in EC (p<0.045). There were no differences in regards to mortality at 30 days, stay in ICU and time of mechanical ventilation between both groups.

CONCLUSION

Preservation of the pulmonary graft with P as preservation liquid compared with EC is associated with better graft function in the initial phases of transplant of both lungs and with a decrease in the incidence of graft dysfunction.

Are heart-lung transplant recipients protected from developing bronchiolitis obliterans syndrome?

BACKGROUND

Heart-lung transplant recipients, when compared with heart transplant recipients, are relatively spared from allograft coronary artery disease. This study was undertaken to investigate whether heart-lung transplant recipients are also spared from experiencing bronchiolitis obliterans syndrome (BOS) when compared with double-lung transplant recipients. In addition, the risk factors for developing BOS after lung transplantation were analyzed.

METHODS

Heart-lung and bilateral sequential double-lung transplant recipients were reviewed retrospectively from 1990 to 2000 using the Stanford Transplant Database. The heart-lung transplant group consisted of 77 heart-lung transplant recipients and the double-lung transplant group consisted of 51 double-lung transplant recipients. The rates of BOS, survival, acute rejection, and cytomegalovirus infection at 1, 3, and 5 years were measured.

RESULTS

There were no significant differences in patient demographics between the two groups. Rates of survival and acute rejection were similar in the two transplant groups. The incidence of cytomegalovirus infection was significantly higher in heart-lung transplant recipients. Freedom from BOS was similar in the two transplant groups. Risk factors for the development of BOS in the heart-lung and double-lung transplant recipients included male donor, younger recipient age, a diagnosis other than cystic fibrosis, nonuse of cardiopulmonary bypass, and the use of OKT3 induction therapy.

CONCLUSIONS

Heart-lung transplant recipients exhibit BOS at a rate similar to double-lung transplant recipients. The immunoprotective effect the lung allograft presumably provides the heart is not reciprocated by the heart in preventing the development of BOS.

Combined lung and liver transplantation: the United States experience

BACKGROUND

Combined transplantation of the lungs and liver is indicated for patients who would not be expected to survive transplantation of either organ alone. No single center has accumulated a significant experience, and as a result the expectations for this operation in the current era are unknown.

METHODS

Patients that have undergone combined lung-liver transplantation in the United States were enrolled through the United Network for Organ Sharing Organ Procurement and Transplantation Network database. In addition, the English-language literature was searched for additional cases of combined lung-liver transplantation.

RESULTS

Eleven patients have undergone combined lung and liver transplantation in the United States at different centers. The 1- and 5-year patient survival rates are of 79% and 63%, respectively, and no patient has required retransplantation. These patient survival rates are equivalent to similar a combined lung-liver case series from the United Kingdom (P=0.37, log-rank test) and isolated orthotopic liver transplantation in the United States (P=0.59, log-rank test), and are comparable to patient survival rates following isolated lung transplantation in the United States.

CONCLUSIONS

Patient survival of combined lung-liver transplantation is comparable to that of isolated liver and isolated bilateral lung transplantation. This option should be considered for patients with end-stage lung disease and liver disease when transplantation of a single organ transplantation is precluded by severe disease in the other organ system.

Transcript signatures of lymphocytic bronchitis in lung allograft biopsy specimens

BACKGROUND

Rejection and obliterative bronchiolitis are barriers to sustained graft function in recipients of transplanted lungs. Early detection is hindered by inadequate tests and an incomplete understanding of the molecular events preceding or accompanying graft deterioration.

METHODS

Hypothesizing that genes involved in immune responses and tissue remodeling produce biomarkers of rejection, we measured the expression of 192 selected genes in 72 sets of biopsy specimens from human lung allografts. Gene transcripts were quantified using a 2-step, multiplex, real-time polymerase chain reaction approach in endobronchial and transbronchial biopsy specimens from transplant recipients without acute infections undergoing routine surveillance bronchoscopy.

RESULTS

Comparisons of histopathology in parallel biopsy specimens identified 6 genes correlating with rejection as manifested by lymphocytic bronchitis, a suspected harbinger of obliterative bronchiolitis. For example, beta2-defensin and collagenase transcripts in inflamed bronchi increased 37-fold and 163-fold, respectively. By contrast, these transcripts did not correlate with acute rejection in transbronchial specimens. Further, no correspondence was noted between histopathologic bronchitis and parenchymal rejection when endobronchial and transbronchial samples were obtained from the same patient.

CONCLUSIONS

Our highly sensitive method permits quantitation of many gene transcripts simultaneously in small, bronchoscopically acquired biopsy specimens of allografts. Transcript signatures obtained by this approach suggest that airway and alveolar responses to rejection differ and that endobronchial biopsy specimens assess lymphocytic bronchitis and chronic rejection but are not proxies for transbronchial biopsy specimens. Further, they reveal changes in airway expression of the specific genes involved in host defense and remodeling and suggest that the measurement of transcripts correlating with lymphocytic bronchitis may be diagnostic adjuncts to histopathology.

Multi-organ transplantation: is there a protective effect against acute and chronic rejection?

BACKGROUND

Heart-lung transplantation (Tx) is known to offer a protective effect against acute cardiac rejection. This study was undertaken to evaluate acute and chronic heart and/or lung rejection in the setting of multiple-transplanted organs from the same donor compared with single-organ transplantation.

METHODS

Acute (treated rejection episodes of heart or lungs) and chronic (allograft vasculopathy in hearts and bronchiolitis obliterans syndrome [BOS] in lungs) rejection events were analyzed in 348 heart transplant (H) recipients, 24 heart-lung (HL) recipients, 82 double-lung (L) recipients and 8 heart-kidney (HK) recipients >18 years of age, who were transplanted between 1990 and 2002.

RESULTS

Survival at 3 years differed among groups as follows: HK, 100%; H, 82%; HL, 74%; and L, 70%. The probability of acute rejection within the first 3 months was higher in H recipients than in HL (81% vs 22%; p < 0.0001) or HK (81% vs 12%; p = 0.00009) recipients. Acute cardiac rejection occurred more frequently during the first 2 years in isolated H recipients compared with HL (2.8 vs 0.27 episodes; p < 0.0001) and HK (2.8 vs 0.54; p < 0.001) recipients. Acute lung rejection occurred more frequently in the first 2 years in L than HL (2.4 vs 1.0 episodes; p = 0.02) recipients. Chronic cardiac rejection (allograft vasculopathy) was more likely within 3 years after H compared with HL (32% vs 16%; p = 0.04) or HK (32% vs 0%; p = 0.14). The onset of chronic lung rejection (BOS) within 3 years was similar in HL and L recipients (39% vs 40%; p = 0.9).

CONCLUSIONS

Recipients of multiple organs from a single donor undergo less acute rejection of the heart or lungs compared with isolated heart or lung transplant recipients. Cardiac allograft vasculopathy is decreased significantly when cardiac transplantation is combined with a lung allograft. A lower incidence of cardiac allograft vasculopathy is observed when cardiac transplantation is combined with a renal allograft, and may prove statistically significant when more cases have been accumulated. These phenomena may result from immune modulation of the recipient by simultaneous transplant of disparate tissues or introduction of immune-modulating hematopoietic elements.

Ten years of "extended" life: quality of life among heart transplantation survivors

BACKGROUND

Long-term quality of life (QOL) outcome in heart transplant recipients still remains uncertain. This study evaluates the health status and QOL of survivors with associated predictors 10 years after heart transplantation.

PATIENTS AND METHODS

A total of 276 patients who underwent heart transplantation in the Department of Cardiac Surgery, University of Pavia, between 1985 and 1992 were included in a cross-sectional study. Patients still alive 10 years after transplantation (n=122) were asked to complete the SF36 questionnaire and then received a full clinical examination. All QOL instruments that were used had acceptable reliability and validity. Descriptive statistics, Kaplan-Meier estimate, correlation coefficients, and general linear regression were used to analyze the data.

RESULTS

Survival rates 1, 5, and 10 years after transplantation were 87%, 77%, and 57%, respectively, and the average life expectancy was 9.16 years. The mental QOL of patients 10 years after heart transplantation was similar to that among the general population. The physical QOL was worse among patients when compared with the QOL of the general population, with predictors including older age, being married, the presence of complications, and impaired renal function.

CONCLUSIONS

Heart transplantation ensures a relatively high QOL even 10 years after surgery. Predictors of a poor QOL were determined, which may help to identify those patients for whom a poor outcome is likely so treatment can be tailored accordingly.

Upregulated hypoxia-inducible factor-1 DNA binding activity to the vascular endothelial growth factor-A promoter mediates increased vascular permeability in donor lung grafts

BACKGROUND

Transplantation-induced hypoxia results in enhanced vascular permeability and tissue vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) overexpression in donor lung grafts. Promoter studies have uncovered a hypoxia-inducible factor (HIF)-1 binding site (HBS) in 5'-flanking region of VEGF gene that regulates the hypoxia-induced expression of VEGF; and ET-1 potently stimulates VEGF-A production. We hypothesized that HIF-1 regulates VEGF-mediated vascular permeability in lung grafts.

METHODS

We studied the mRNA and protein expression of HIF-1 and its protein-binding capacity to the HBS of the VEGF gene in biopsies of preserved donor and control lungs, using real-time reverse transcription-polymerase chain reaction, Western blotting, and electrophoretic mobility shift assay. Wet-to-dry lung weight ratio was measured in donor and control lungs.

RESULTS

While HIF-1 alpha mRNA expression was unchanged, HIF-1 beta was downregulated (p < 0.05) in donor versus control lungs. Protein expression of both, HIF-1 alpha and -beta was significantly upregulated in donor lung grafts. HIF-1 binding to the HBS of the VEGF promoter as well as tissue fluid content were increased in donor lung biopsies versus controls (p < 0.05).

CONCLUSIONS

These data indicate that upregulated HIF-1 DNA binding activity to the HBS of VEGF-A most likely contributes to elevated VEGF levels in preserved lung grafts. Unchanged HIF-1 alpha mRNA expression did not affect HIF-1 alpha protein levels. Endothelin-1 increases HIF-1 alpha accumulation and activates HIF-1 transcription complex in vitro. Therefore, ET-1-mediated increased HIF-1 alpha protein stability most likely leads to transcriptional activation of VEGF during lung graft preservation. Targeting HIF might be of benefit to counteract edema formation in preserved lung grafts.