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. The V122I gene mutation is most common among people of African descent and usually manifests with cardiomyopathy. The mutations are transmitted in an autosomal dominant manner with variable penetrance and associated with clinical features occurring most commonly after the age of 40. The symptoms of heart failure (HF) may be preceded by several years of vague neurological symptoms which is more concerning if there is no clear explanation. A high index of suspicion is therefore crucial in ensuring prompt diagnosis and therapy, as this may favorably alter the gloomy prognosis associated with cardiac amyloidosis.