Transthyretin amyloid cardiomyopathy: from cause to novel treatments.

Abstract

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive disorder marked by amyloid deposition in the heart, ultimately impairing cardiac function. Recent treatment advances have paralleled an evolving understanding of ATTR-CM pathophysiology. One emerging hypothesis suggests that an imbalance between in vivo amyloid production and natural clearance may drive disease progression, a conceptual framework that still requires validation. Transthyretin (TTR) stabilizers, such as tafamidis and acoramidis, mitigate amyloid formation by promoting the native tetrameric conformation of circulating TTR, thereby slowing functional decline and prolonging survival. Similarly, TTR gene silencers inhibit hepatic TTR synthesis, and gene-editing therapy with nexiguran ziclumeran offers an additional strategy to reduce amyloid production. However, these approaches do not enhance the body's limited capacity to clear existing amyloid deposits, underscoring the need for novel agents that accelerate amyloid removal. Promisingly, monoclonal antibodies targeting TTR amyloid are under development, with early clinical trials suggesting that this passive immunotherapy may reverse disease progression and improve heart function. Ultimately, optimal management of ATTR-CM will require further elucidation of the complex interplay between amyloid formation, its structural and functional impacts, its clearance mechanisms, and the potential for myocardial reverse remodelling.