Refractory Heart Failure of Unknown Etiology May Be Cardiac Amyloid If Preceded by Hereditary Neurological Symptoms.

Transthyretin cardiac amyloidosis results from the deposition of transthyretin amyloid fibrils in the myocardium. This happens because of the misfolding of genetically normal (wild type - ATTR) or mutant (hereditary ATTR) transthyretin. The clinical presentation of hereditary ATTR cardiac amyloidosis is dependent on the exact site of the amino acid substitution.