Early cardiac involvement in senile systemic amyloidosis: a case report

Senile systemic amyloidosis (SSA) is caused by the deposition of wild-type transthyretin (TTR)-derived amyloid fibrils. This type of amyloidosis is not rare in elderly individuals over the age of 80 and is usually detected on postmortem microscopic examination of myocardium. We report a 67-year-old male patient who was clinically diagnosed as having SSA with cardiac involvement. The initial event was cerebral infarction conceivably due to cardiac embolism. Endomyocardial biopsy was performed twice, which led to a definitive diagnosis of amyloidosis at the second biopsy. This amyloid was immunolabeled by an anti-TTR antibody and direct DNA sequencing of the TTR gene did not detect any mutation. Clinical confirmation of SSA in individuals before the age of 70 is infrequent and cardiac amyloidosis associated with this disease might have been the cause of cerebral embolism in our patient. Additionally, it is important to distinguish cardiac amyloidosis of SSA from that of primary immunoglobulin light chain (AL)-derived amyloidosis, because the treatment and prognosis differ considerably from those of primary AL amyloidosis.