Combined heart and liver transplantation: protection of the cardiac graft from antibody rejection by initial liver implantation

Anesthesia for Combined Heart-Liver Transplantation: A Narrative Review

In 1984, 21 years after the first liver transplantation, Thomas Starzl achieved a milestone by performing the world's first combined heart-liver transplantation. While still uncommon, the practice of combined heart-liver transplants is on the rise globally. In this review, the authors delve into the current literature on this procedure, highlighting the evolving landscape and key considerations for anesthesiologists. Over the years, there has been a remarkable increase in the number of combined heart-liver transplantations conducted worldwide. This surge is largely attributed to the growing population of adult survivors with single-ventricle physiology, palliated with a Fontan procedure, who later present with late Fontan failure and Fontan-associated liver disease. Research indicates that combined heart-liver transplantation is an effective treatment option, with reported outcomes comparable with isolated heart or liver transplants. Managing anesthesia during a combined heart-liver transplant procedure is challenging, especially in the context of underlying Fontan physiology. International experience in this field remains somewhat limited, with most techniques derived from expert opinions or experiences with single-organ heart and liver transplants. These procedures are highly complex and performed infrequently. As the number of combined heart-liver transplants continues to rise globally, there is a growing need for clear guidance on periprocedural surgical and anesthetic management. Anesthesiologists overseeing these patients must consider multiple factors, balancing various comorbidities with significant hemodynamic and metabolic shifts. An increase in (multicenter) studies focusing on specific interventions to enhance patient and organ outcomes is anticipated in the coming years.

Incidence of acute rejection and patient survival in combined heart-liver transplantation

Combined heart-liver transplantation (CHLT) is indicated for patients with concomitant end-stage heart and liver disease or patients with amyloid heart disease where liver transplantation mitigates progression. Limited data suggest that the liver allograft provides immunoprotection for heart and kidney allografts in combined transplantation from the same donor. We hypothesized that CHLT reduces the incidence of acute cellular rejection (ACR) and the development of de novo donor-specific antibodies (DSAs) compared with heart-alone transplantation (HA). We conducted a retrospective analysis of 32 CHLT and 280 HA recipients in a single-center experience. The primary outcome was incidence of ACR based on protocol and for-cause myocardial biopsy. Rejection was graded by the International Society of Heart and Lung Transplantation guidelines with Grade 2R and higher considered significant. Secondary outcomes included the development of new DSAs, cardiac function, and patient and cardiac graft survival rates. Of CHLT patients, 9.7% had ACR compared with 45.3% of HA patients (p < 0.01). Mean pretransplant calculated panel reactive antibody (cPRA) levels were similar between groups (CHLT 9.4% vs. HA 9.5%; p = 0.97). Among patients who underwent testing, 26.9% of the CHLT and 16.7% of HA developed DSA (p = 0.19). Despite the difference in ACR, patient and cardiac graft survival rates were similar at 5 years (CHLT 82.1% vs. HA 80.9% [p = 0.73]; CHLT 82.1% vs. HA 80.9% [p = 0.73]). CHLT reduced the incidence of ACR in the cardiac allograft, suggesting that the liver offers immunoprotection against cellular mechanisms of rejection without significant impacts on patient and cardiac graft survival rates. CHLT did not reduce the incidence of de novo DSA, possibly portending similar long-term survival among cardiac allografts in CHLT and HA.

Symptomatic Val122del mutated hereditary transthyretin amyloidosis: Need for early diagnosis and prioritization for heart and liver transplantation

BACKGROUND

Hereditary transthyretin (ATTRv) amyloidosis is an autosomal dominant disease linked to transthyretin gene mutations which cause instability of the transthyretin tetramer. After dissociation and misfolding they reassemble as insoluble fibrils (i.e. amyloid). Apart from the common Val30Met mutation there is a very heterogeneous group of non-Val30Met mutations. In some cases, the clinical picture is dominated by a rapidly evolving restrictive and hypertrophic cardiomyopathy.

METHODS

A case series of four liver recipients with the highly clinically relevant, rare and particularly aggressive Val122del mutation is presented. Medical and surgical therapeutic options, waiting list policy for ATTRv-amyloidosis, including the need for heart transplantation, and status of heart-liver transplantation are discussed.

RESULTS

Three patients needed a staged (1 patient) or simultaneous (2 patients) heart-liver transplant due to rapidly progressing cardiac failure and/or neurologic disability. Domino liver transplantation was impossible in two due to fibrotic hepatic transformation caused by cardiomyopathy. After a follow-up ranging from 3.5 to 9.5 years, cardiac (allograft) function was maintained in all patients, but neuropathy progressed in three patients, one of whom died after 80 months.

CONCLUSIONS

This is the first report in (liver) transplant literature about the rare Val122del ATTRv mutation. Due to its aggressiveness, symptomatic patients should be prioritized on the liver and, in cases with cardiomyopathy, heart waiting lists in order to avoid the irreversible neurological and cardiac damage that leads to a rapid lethal outcome.

Simultaneous Heart-Liver Transplantation for Congenital Heart Disease in the United States: Rapidly Increasing With Acceptable Outcomes

BACKGROUND AND AIMS

There are more adults than children living with congenital heart disease (CHD) in the United States, with a growing proportion requiring heart-liver transplantation (HLT). Our aim was to ascertain the frequency, outcomes, and prognostic factors in this patient population.

APPROACH AND RESULTS

United Network for Organ Sharing data on adult patients who underwent heart transplantation (HT) from 2009 through March 2020 were analyzed. The primary study outcome was patient survival. Cox proportional-hazards modeling assessed for mortality associations. There were 1,084 HT recipients: 817 (75.4%) CHD HTs only, 74 (6.8%) CHD HLTs, 179 (16.5%) non-CHD HLTs, and 14 (1.3%) heart-liver-kidney transplants. The number of CHD HLTs increased from a prior rate of 4/year to 21/year in 2019. Among patients with CHD, the 5-year survival rates were 74.1% and 73.6% in HTs only and HLTs, respectively (P = 0.865). There was a higher rate of allograft failure attributable to rejection in CHD HTs only compared with CHD HLTs (3.2% versus 0.4%; P = 0.014). Only 25 out of 115 HT-performing hospitals undertook CHD HLTs. Higher-volume centers (averaging one CHD HLT per year) had a 5-year patient survival rate of 83.0% compared with 61.3% in lower-volume centers (P = 0.079). Among HLT recipients, total bilirubin (hazard ratio [HR], 1.06; 95% confidence interval [CI], 1.01-1.12) and diabetes (HR = 2.97, 95% CI = 1.21-7.31) were independently associated with increased mortality risk, whereas CHD and age were not.

CONCLUSIONS

The rate of HLT for adult CHD in the United States is rising dramatically. The survival outcomes between CHD HT only and CHD HLT groups are comparable; however, the HLT group had lower rates of acute rejection. Among HLT recipients, diabetes and elevated bilirubin are associated with increased posttransplant mortality risk. An average of one CHD HLT per year could be considered a minimum quality metric at transplant centers.

Heart-After-Liver Transplantation Attenuates Rejection of Cardiac Allografts in Sensitized Patients

BACKGROUND

In patients undergoing heart transplantation, significant allosensitization limits access to organs, resulting in longer wait times and high waitlist mortality. Current desensitization strategies are limited in enabling successful transplantation.

OBJECTIVES

The purpose of this study was to describe the cumulative experience of combined heart-liver transplantation using a novel heart-after-liver transplant (HALT) protocol resulting in profound immunologic protection.

METHODS

Reported are the results of a clinical protocol that was instituted to transplant highly sensitized patients requiring combined heart and liver transplantation at a single institution. Patients were dual-organ listed with perceived elevated risk of rejection or markedly prolonged waitlist time due to high levels of allo-antibodies. Detailed immunological data and long-term patient and graft outcomes were obtained.

RESULTS

A total of 7 patients (age 43 ± 7 years, 86% women) with high allosensitization (median calculated panel reactive antibody = 77%) underwent HALT. All had significant, unacceptable donor specific antibodies (DSA) (>4,000 mean fluorescence antibody). Prospective pre-operative flow cytometric T-cell crossmatch was positive in all, and B-cell crossmatch was positive in 5 of 7. After HALT, retrospective crossmatch (B- and T-cell) became negative in all. DSA fell dramatically; at last follow-up, all pre-formed or de novo DSA levels were insignificant at <2,000 mean fluorescence antibody. No patients experienced >1R rejection over a median follow-up of 48 months (interquartile range: 25 to 68 months). There was 1 death due to metastatic cancer and no significant graft dysfunction.

CONCLUSIONS

A heart-after-liver transplantation protocol enables successful transplantation via near-elimination of DSA and is effective in preventing adverse immunological outcomes in highly sensitized patients listed for combined heart-liver transplantation.

Considerations and experience driving expansion of combined heart-liver transplantation

PURPOSE OF REVIEW

Heart transplantation concomitant with a liver transplant may be warranted when end-stage heart failure results in irreversible liver failure. Previously reported outcomes have been excellent yet the specific immunoprotective role of the liver allograft is not known. We review the current literature about the immunologic benefit for combined heart and liver transplantation (CHLT).

RECENT FINDINGS

The total number of combined heart and liver transplants continues to increase and accounts for approximately 25 cases per year. Familial amyloid polyneuropathy with cardiac cirrhosis is the most common indication for CHLT while adult congenital heart disease (CHD) with associated cirrhosis is increasing in frequency. The majority of recent registry data suggest a statistically equivalent to modestly improved survival advantage for CHLT compared with isolated heart transplantation. Direct mechanisms accounting for this survival advantage are not proven, but combined heart and liver transplants experience lower rates of acute cardiac rejection and cardiac allograft vasculopathy (CAV).

SUMMARY

Combined heart and liver transplants remain a small percentage of the total heart transplants worldwide, but the majority of recent literature confirms the safety and viability of this option for patients with end-stage heart and liver disease. Equivalent to modestly improved survival outcomes, lower rates of acute cardiac rejection and CAV warrant further investigation into the liver allograft's immunoprotective effect on the transplanted heart. The key mechanisms of tolerogenicity have important implications for surgical technique and immunosuppression requirements. Future directions include development of criteria for heart-liver transplant candidacy and identification of equitable allocation protocols.

Combined Thoracic and Abdominal Organ Transplantation: Special Considerations

Combined thoracic-abdominal organ transplants are infrequently performed procedures indicated for patients with failure of two or more transplantable organs. In this review, we discuss recipient selection, surgical considerations, anesthetic management, and outcomes associated with common combinations of thoracic-abdominal transplant operations. General principles regarding the postoperative care of these patients are also discussed. These procedures present a unique challenge requiring specialized knowledge, technical expertise, and leadership from the anesthesiology team throughout the perioperative period.

32 Doses of Bortezomib for Desensitization Is Not Well Tolerated and Is Associated With Only Modest Reductions in Anti-HLA Antibody

BACKGROUND

We previously showed that bortezomib (BTZ) partially depletes plasma cells, yet has limited efficacy for desensitization in kidney transplant candidates when up to 16 doses is given.

METHODS

This study aimed to determine the safety and efficacy of 32 doses of BTZ (1.3 mg/m of body surface area) in 10 highly sensitized kidney transplant candidates with alloantibodies against their intended living donor.

RESULTS

Dose reduction was needed in 2 patients and 2 others completely discontinued therapy for adverse events. Anti-HLA antibodies mean fluorescence intensity (MFI) values were stable prior to BTZ (P = 0.96) but decreased after therapy (mean decrease of 1916 [SE, 425] MFI, P < 0.01). No patient developed a negative crossmatch against their original intended donor, and the calculated panel-reactive antibodies based on MFI of 2000, 4000, and 8000 was unchanged in all patients.

CONCLUSIONS

These data suggest that 32 doses of BTZ monotherapy was not well tolerated and resulted in only a modest reduction in anti-HLA antibodies.

Impact of CXCR4/CXCL12 Blockade on Normal Plasma Cells In Vivo

Plasma cells (PCs) are a major source of alloantibody in transplant patients and are resistant to current therapy. Because receptor-ligand interactions in stromal microenvironments play important roles in the localization, development, and survival of normal PCs, we hypothesized that interfering with CXCR4/CXCL12 interactions with plerixafor might cause PC depletion and enhance the efficacy of the proteasome inhibitor bortezomib. PCs in mouse spleen, bone marrow, and peripheral blood demonstrated CXCR4 expression. We then treated with plerixafor in doses ranging from 240 μg/kg in a single dose to a 1-mg/kg daily dose for 10 days. CXCR4/CXCL12 blockade with plerixafor resulted in increased mobilization of PCs into the peripheral blood. Splenectomy completely abrogated this effect, suggesting that all plerixafor-mobilized cells were from the spleen. The total number of PCs in the spleen and marrow remained constant despite treatment with plerixafor. Bortezomib caused a reduction in PCs, but adding plerixafor did not increase killing. We conclude that CXCR4/CXCL12 interactions are important for the retention of a subpopulation of PCs in the spleen, but this interaction has minimal effect on PCs in the marrow. The lack of enhancement of bortezomib-mediated depletion suggests that factors other than CXCR4/CXCL12 interactions are responsible for drug resistance.

Single-center outcomes of combined heart and liver transplantation in the failing Fontan

Long-term outcomes of the Fontan operation include Fontan failure and liver disease. Combined heart-liver transplantation (CHLT) is an option for select patients although limited data exist on this strategy. A retrospective review of Fontan patients 18 years or older referred for cardiac transplant evaluation between 2000 and 2013 at the Hospital of the University of Pennsylvania was performed. All patients were considered for potential CHLT. Clinical variables such as demographics, perioperative factors, and short-term outcomes were reviewed. Of 17 referrals for cardiac transplantation, seven Fontan patients underwent CHLT. All patients who underwent CHLT had either advanced fibrosis or cirrhosis on liver biopsy. There were no perioperative deaths. The most common postoperative morbidity was acute kidney injury. Short-term complications include one episode of acute liver rejection but no cardiac rejection greater than 1R. CHLT is an acceptable therapeutic option for patients with failing Fontan physiology who exhibit concomitant advanced liver fibrosis. However, optimal patient selection is currently undefined, and long-term outcomes are not known.

Liver Allograft Provides Immunoprotection for the Cardiac Allograft in Combined Heart-Liver Transplantation

When transplanted simultaneously, the liver allograft has been thought to have an immunoprotective role on other organs; however, detailed analyses in simultaneous heart-liver transplantation (SHLT) have not been done to date. We analyzed patient outcomes and incidence of immune-mediated injury in 22 consecutive SHLT versus 223 isolated heart transplantation (IHT) recipients between January 2004 and December 2013, by reviewing 3912 protocol- and indication-specific cardiac allograft biopsy specimens. Overall survival was similar (86.4%, 86.4%, and 69.1% for SHLT and 93.3%, 84.7%, and 70.0% for IHT at 1, 5, and 10 years; p = 0.83). Despite similar immunosuppression, the incidence of T cell-mediated rejection (TCMR) was lower in SHLT (31.8%) than in IHT (84.8%) (p < 0.0001). Although more SHLT patients had preexisting donor-specific HLA antibody (22.7% versus 8.1%; p = 0.04), the incidence of antibody-mediated rejection was not different in SHLT compared with IHT (4.5% versus 14.8%, p = 0.33). While the left ventricular ejection fraction was comparable in both groups at 5 years, the incidence and severity of cardiac allograft vasculopathy were reduced in the SHLT recipients (42.9% versus 66.8%, p = 0.03). Simultaneously transplanted liver allograft was associated with reduced risk of TCMR (odds ratio [OR] 0.003, 95% confidence interval [CI] 0-0.02; p < 0.0001), antibody-mediated rejection (OR 0.04, 95% CI 0-0.46; p = 0.004), and cardiac allograft vasculopathy (OR 0.26, 95% CI 0.07-0.84; p = 0.02), after adjusting for other risk factors. These data suggest that the incidence of alloimmune injury in the heart allograft is reduced in SHLT recipients.

Combined heart-liver transplantation: Indications, outcomes and current experience

Combined heart-liver transplantation is a rare, life-saving procedure that treats complex and often fatal diseases including familial amyloidosis polyneuropathy and late stage congenital heart disease status-post previous repair. There were 159 combined heart-liver transplantations performed between January 1, 1988 and October 3, 2014 in the United States. A multitude of potential techniques to be used for combined heart and liver transplant including: orthotopic heart transplant (OHT) and orthotopic liver transplant (OLT) on full cardiopulmonary bypass (CPB), OHT with CPB and OLT with venovenous bypass (VVB), OHT with CPB and OLT without VVB, en-bloc technique and sequential transplantation. Outcomes of combined heart-liver transplant have been demonstrated to be comparable to outcomes of isolated heart and isolated liver transplant. The liver graft may provide some tolerance of other allografts.

Current Antioxidant Treatments in Organ Transplantation

Oxidative stress is one of the key mechanisms affecting the outcome throughout the course of organ transplantation. It is widely believed that the redox balance is dysregulated during ischemia and reperfusion (I/R) and causes subsequent oxidative injury, resulting from the formation of reactive oxygen species (ROS). Moreover, in order to alleviate organ shortage, increasing number of grafts is retrieved from fatty, older, and even non-heart-beating donors that are particularly vulnerable to the accumulation of ROS. To improve the viability of grafts and reduce the risk of posttransplant dysfunction, a large number of studies have been done focusing on the antioxidant treatments for the purpose of maintaining the redox balance and thereby protecting the grafts. This review provides an overview of these emerging antioxidant treatments, targeting donor, graft preservation, and recipient as well.

Combined heart-liver transplantation: a single-center experience

Combined orthotopic heart and liver transplantation (CHLT) is a lifesaving procedure for patients with end-stage heart-liver disease. We reviewed the long-term outcome of patients who have undergone CHLT at the University of Bologna, Italy. Fifteen patients with heart and liver failure were placed on the transplant list between November 1999 and March 2012. The pretransplant cardiac diagnoses were familial amyloidosis in 14 patients and chronic heart failure due to chemotherapy with liver failure due to chronic hepatitis in one patient. CHLT was performed as a single combined procedure in 14 hemodynamically stable patients; there was no peri-operative mortality. The survival rates for the CHLT recipients were 93%, 93%, and 82% at 1 month and 1 and 5 years, respectively. Freedom from graft rejection was 100%, 90%, and 36% at 1, 5, and 10 years, respectively, for the heart graft and 100%, 91%, and 86% for the liver graft. The livers of eight recipients were transplanted as a "domino" with mean overall 1-year survival of 93%. Simultaneous heart and liver transplantation is feasible and was achieved in this extremely sick cohort of patients. By adopting the domino technique, we were able to enlarge the donor cohort and include high-risk patients.

Combined liver and lung transplantation with extended normothermic lung preservation in a patient with end-stage emphysema complicated by drug-induced acute liver failure

Isolated lung transplantation (LuTx) and liver transplantation are established treatments for irreversible lung and liver failure. Combined liver and lung transplantation (cLiLuTx) is a less common, but approved therapy of combined organ failure, mostly applied in patients suffering from progressive cystic fibrosis and advanced liver disease. We report a patient who was listed for LuTx due to end-stage chronic obstructive pulmonary disease and who developed drug-induced acute hepatic failure. The only therapeutic option was hyper-urgent cLiLuTx. To correct the poor coagulation in order to reduce the per-operative risk of bleeding, the liver was transplanted first. In anticipation of the longer lung preservation time, cold flushed lungs were preserved on a portable lung perfusion device for ex vivo normothermic perfusion for 11 h 15 min, transplanted sequentially off-pump, and reperfused after a total ex vivo time of 13 h 32 min and 16 h for the first and second lung, respectively. Ten months later, the patient is doing well and no rejection occurred. Normothermic ex vivo lung perfusion may help to prolong preservation time, facilitating long-distance transport and combined organ transplantation.

Down-regulating humoral immune responses: implications for organ transplantation

Alloantibody can be a major barrier to successful organ transplantation; however, therapy to control antibody production or to alter its impact on the allograft remains limited. The goal of this review is to examine the regulatory steps that are involved in the generation of alloreactive B cells, with a specific emphasis on how known mechanisms relate to clinical situations in transplant recipients. Thus, we will examine the process of activation of mature, naïve B cells and how this relates to de novo antibody production. The role of long-lived plasma cells in persistent antibody production and the factors regulating their longevity will be explored. The regulation of memory B cells and their possible roles in alloimmunity also will be assessed. Finally, we will review current therapeutic approaches aimed at controlling alloantibody and assess their efficacy. By examining the pathways to antibody production mechanistically, we hope to identify important gaps in our current knowledge and gain insight into possible new therapeutic approaches to overcoming antibody in transplant patients.