The most common clinical symptom leading to a diagnosis of ATTR-CM is HF [9], but if the disease can be diagnosed early, before the onset of symptoms or at least while compensatory functions are still working, the prognosis may be improved by early initiation of TTR-specific therapies such as suppression of TTR synthesis, TTR stabilization, and TTR disruption/resorption [1,27,28,29]. This evidence concerns the gene TTR and hydrops fetalis.