Liver Transplantation for Familial Amyloid Polyneuropathy Non-VAL30MET Variants: Are Cardiac Complications Influenced by Prophylactic Pacing and Immunosuppressive Weaning?

Perioperative Characteristics of Siblings Undergoing Liver or Kidney Transplant

OBJECTIVES

Reasons for chronic liver and kidney failure may vary; sometimes more than 1 family member may be affected, and may require a transplant. The aim of this study was to examine the similarities or differences between the perioperative characteristics of siblings undergoing liver or kidney transplant.

MATERIALS AND METHODS

The medical records of 6 pairs of siblings who underwent liver transplant and 4 pairs of siblings who underwent kidney transplant at Baskent University Hospital between 1989 and 2014 were retrospectively analyzed. Collected data included demographic features; comorbidities; reasons for liver and kidney failure; perioperative laboratory values; intraoperative hemodynamic parameters; use and volume of crystalloids, colloids, blood products, cell saver system, and albumin; duration of anesthesia; urine output; and postoperative follow-up data.

RESULTS

The mean age of the 6 sibling pairs who underwent liver transplant was 16.3 ± 12.2 years. All 12 patients had Child-Pugh grade B cirrhosis, with mean disease duration of 7.8 ± 3.9 years. There were no significant differences between siblings with respect to intraoperative blood product transfusion, crystalloid and colloid fluid replacements, hypotension frequency, blood gas analyses, urinary output, duration of anhepatic phase, inotropic agent administration, postoperative laboratory values, need for mechanical ventilation and vasopressors, occurrence of acute renal failure and infections, and duration intensive care unit stay (P > .05). The mean age of the 4 sibling pairs who underwent kidney transplant was 21.3 ± 6.4 years, with mean duration of renal insufficiency of 2.2 ± 1.6 years. There were no significant differences between siblings with respect to intraoperative crystalloid and colloid fluid administration, duration of anesthesia, intraoperative mannitol and furosemide administration, and postoperative laboratory values (P > .05).

CONSLUSIONS

In conclusion, the 6 sibling pairs who underwent liver transplant and 4 sibling pairs who underwent kidney transplant in our cohort had similar perioperative characteristics.

Survival After Transplantation in Patients With Mutations Other Than Val30Met: Extracts From the FAP World Transplant Registry

Background

Liver transplantation (LTx) has been performed for hereditary transthyretin amyloidosis (ATTR) since 1990. Outcomes for a relatively large series of LTx ATTR patients with the Val30Met (mutation are available, but for non-Val30Met patients, only a few reports with a small number of patients exist. Here, we present outcomes for non-Val30Met ATTR patients after LTx, as reported to the Familial Amyloid Polyneuropathy World Transplant Registry (FAPWTR).

Methods

Data regarding outcome were extracted for all non-Val30Met patients reported to the registry. Survival rates were analyzed by the Kaplan-Meier method and log-rank test.

Results

The total number of patients with a non-Val30Met mutation in the registry was 264 (174 men and 90 women), representing 57 mutations. The 10-year survival varied markedly for the 9 most common mutations, ranging from 21% for Ser50Arg to 85% for Val71Ala. Poor survival was noted for all mutations with leptomeningeal complications except for those with the Tyr114Cys mutation.

Conclusions

Large differences in survival were observed relative to different mutations and between mutations with similar phenotypes. Excellent survival was noted for mutations, such as Leu111Met, Val71Ala, and Leu58His. Patients with mutations other than Val30Met are not a homogeneous group, and the term non-Val30Met should be used with caution or avoided. Moreover, for several mutations, data are too limited to allow evaluation of the efficacy of LTx, and continuous international collaboration is important for obtaining treatment guidance.

Dissecting the structure, thermodynamic stability, and aggregation properties of the A25T transthyretin (A25T-TTR) variant involved in leptomeningeal amyloidosis: identifying protein partners that co-aggregate during A25T-TTR fibrillogenesis in cerebrospinal fluid

Deposition of amorphous aggregates and fibrils of transthyretin (TTR) in leptomeninges and subarachnoid vessels is a characteristic of leptomeningeal amyloidosis (LA), a currently untreatable cerebral angiopathy. Herein, we report the X-ray structure of the A25T homotetramer of TTR, a natural mutant described in a patient with LA. The structure of A25T-TTR is indistinguishable from that of wild-type TTR (wt-TTR), indicating that the difference in amyloidogenicity between A25T-TTR and wt-TTR cannot be ascribed to gross structural differences. Using pressure-induced dissociation of the tetramer, we show that A25T-TTR is 3 kcal/mol less stable than L55P-TTR, the most aggressive mutant of TTR described to date. After incubation for 15 days at 37 °C (pH 7.3), A25T-TTR forms mature amyloid fibrils. To mimic the environment in which TTR aggregates, we investigated aggregation in cerebrospinal fluid (CSF). Unlike L55P-TTR, A25T-TTR rapidly forms amyloid aggregates in CSF that incorporated several protein partners. Utilizing a proteomics methodology, we identified 19 proteins that copurified with A25T-TTR amyloid fibrils. We confirmed the presence of proteins previously identified to be associated with TTR aggregates in biopsies of TTR amyloidosis patients, such as clusterin, apolipoprotein E, and complement proteins. Moreover, we identified novel proteins, such as blood coagulation proteins. Overall, our results revealed the in vitro characterization of TTR aggregation in a biologically relevant environment, opening new avenues of investigation into the molecular mechanisms of LA.

Liver transplantation and combined liver-heart transplantation in patients with familial amyloid polyneuropathy: a single-center experience

Liver transplantation (LT) is the only curative option for patients with familial amyloid polyneuropathy (FAP) at present. Twenty patients with FAP underwent LT between May 1998 and June 2007. Transthyretin mutations included predominantly the Val30Met mutation but also 10 other mutations. Seven patients received a pacemaker prior to LT, and because of impairment of mechanical cardiac function, 4 combined heart-liver transplants were performed, 1 simultaneously and 3 sequentially. The first patient, who underwent simultaneous transplantation, died. Seven patients died after LT, with 5 dying within the first year after transplantation. The causes of death were cardiac complications (4 patients), infections (2 patients), and malnutrition (1 patient). One-year survival was 75.0%, and 5-year survival was 64.2%. Gly47Glu and Leu12Pro mutations showed an aggressive clinical manifestation: 2 patients with the Gly47Glu mutation, the youngest patients of all the non-Val30Met patients, suffered from severe cardiac symptoms leading to death despite LT. Two siblings with the Leu12Pro mutation, who presented only with grand mal seizures, died after LT because of sepsis. In conclusion, the clinical course in patients with FAP is very variable. Cardiac symptoms occurred predominantly in patients with non-Val30Met mutations and prompted combined heart-liver transplantation in 4 patients. Although early LT in Val30Met is indicated in order to halt the typical symptoms of polyneuropathy, additional complications occurring predominantly with other mutations may prevail and lead to life-threatening complications or a fatal outcome. Combined heart-liver transplantation should be considered in patients with restrictive cardiomyopathy.

Combined heart and liver transplantation: a single-center experience

BACKGROUND

Simultaneous combined orthotopic heart and liver transplantation (CHLTx) remains a lifesaving procedure for the patients suffering from coincident end-stage heart and liver disease and several metabolic disorders. We analyze the long-term outcome of the patients undergoing CHLTx.

METHODS

Between January 1992 and May 2007, 15 CHLTx were attempted at the Mayo Clinic including two combined heart, liver, and kidney transplantations and one combined heart, lung, and liver transplantations. Pretransplant cardiac diagnoses were familial amyloidosis (11), hemochromatosis (1), restrictive cardiomyopathy and cardiac cirrhosis (1), previously operated congenital heart disease and cardiac cirrhosis (1), and primary pulmonary hypertension with primary biliary cirrhosis (1).

RESULTS

Heart and liver transplantation were performed as a single combined procedure in 13 (93%) hemodynamically stable patients, and there was no perioperative mortality. Survival rates for the CHLTx recipients at 1 year, 5 years, and 10 years were 100%, 75%, and 60%, respectively, and did not differ from survival after isolated heart transplantation (93%, 83%, and 65%, respectively, P=0.39). Freedom from cardiac allograft rejection (ISHLT > or =grade 2) for CHLTx was 83% at 1 month, did not change with time, and was lower than after isolated heart transplantation (P=0.02). At the mean follow-up of 61.6+/-53.6 months, normal left ventricular ejection fraction and good liver allograft function were demonstrated. Three patients developed end-stage renal failure secondary to calcineurin nephrotoxicity.

CONCLUSION

Simultaneous heart and liver transplantation is feasible and achieved excellent results for selected patients.