ATTRv is a severe and progressive disease that arises when the transthyretin protein aggregates with amyloid and accumulates in various organs and tissues throughout the body. These protein deposits eventually disrupt proper organ and nerve function, leading to neuropathy and cardiomyopathy, which, when left unchecked, can severely interfere with activities of daily living and worsen the quality of life. ATTRv can also lead to premature death, with patients living for a median of 4.7 years after diagnosis.