Amyloidosis is a term that encompasses a group of diseases characterized by the extracellular accumulation of a pathological protein in various organ systems. Transthyretin amyloidosis is of particular interest to abdominal surgeons because of the possibility of treating it with a liver transplantation. Transthyretin amyloidosis (ATTR) is caused by an error in the synthesis and deposition of transthyretin, a protein that is synthesized almost exclusively in the liver. ATTR can be further divided into two groups: wild type ATTR (wATTR) and hereditary ATTR (hATTR). wATTR is a sporadic disease that manifests in old age, more often in men. hATTR arises as a result of a mutation of the TTR gene, and is inherited in an autosomal dominant manner, and manifests itself at a younger age than wATTR. ATTR most often causes neuropathy and restrictive cardiomyopathy leading to cardiac decompensation. Patients with wATTR generally have disease limited to the heart, but since the disease is usually diagnosed in their seventh or eighth decade of life, they are not candidates for heart transplantation. Patients with hATTR are mostly younger patients who may be candidates for heart transplantation. Since the mutated gene is synthesized in the liver, it is necessary to consider a combined liver and heart transplant in such patients. The first synchronous heart and liver transplant was performed in 1984. on a 6-year-old girl diagnosed with familial hypercholesterolemia. Since then, synchronous transplants of multiple organs have been performed around the world, but still rarely and in strictly specialized centers, which is confirmed by the fact that in USA annualy less than 50 synchronous liver and heart transplantation are performed. This paper contains a summary of today's knowledge about transthyretin amyloidosis and methods of treatment, as well as a case report of a patient who underwent such synchronous liver and heart transplantation for hATTR for the first time in Croatia.