Posicionamento sobre Diagnóstico e Tratamento da Amiloidose Cardíaca – 2021

Abstract

Nota: Estes posicionamentos se prestam a informar e não a substituir o julgamento clínico do médico que, em última análise, deve determinar o tratamento apropriado para seus pacientes.

Taquicardia Ventricular Sustentada como Apresentação Isolada de Cardiomiopatia Amiloidótica por Transtirretina - Val50Met

“…No entanto, agora com a introdução do tratamento específico, principalmente se o paciente se encontra numa fase mais precoce de evolução da doença, em classe funcional I/II da NYHA é provável que esta recomendação seja modificada em diretrizes, por ser possível a expectativa de sobrevida razoável. 1…”

“…Entre elas, a amiloidose por transtirretina (ATTR), que pode ocorrer por uma variante genética e pelo envelhecimento. 1 Cerca de 120 variantes genéticas são reconhecidamente a causa da ATTR entre elas, uma das mais comuns é a representada pela Val50Met. A apresentação fenotípica da amiloidose TTR pela mutação Val50Met é majoritariamente neurológica, chamada de polineuropatia amiloidótica familiar (PAF), porém o envolvimento cardíaco está cada vez mais sendo reconhecido.…”

First Combined Heart-Liver Transplant in Amyloidosis Due to Transthyretin Mutation in Brazil: Impact of the Liver on Reducing anti-HLA Antibodies

“…Due to the reduced size of the left ventricular cavity and the frequent involvement of the right ventricle, there may be limitations to the use of long-term mechanical circulatory assist devices. 1 From an immunological point of view, CHLT shows a lower incidence of rejection, whether cellular or antibody-mediated. 3,4, Many mechanisms have been proposed to explain the tolerance properties of the liver which may possibly act simultaneously to reduce risk of rejection; among them, we can highlight the ability to secrete soluble class I HLA antigens, allied to the great capacity for absorption and neutralization of alloantibodies directed against HLA antigens.…”

Genetic Testing in Amyloidosis: For Whom?

“…Subsequently, the partial denaturation of the monomer can lead to incorrect assembly of this protein in various aggregate structures. 6 When this inappropriate assembly is caused by a mutation in the TTR gene, changing the amino acid sequence, it is known as variant or hereditary TTR amyloidosis (ATTRv). This mutation has an autosomal dominant character; its gene is located on chromosome 18, and several types of mutations have been described.…”

“…7 It is precisely in this scenario of differentiating between ATTRv (the hereditary form) and ATTRwt (the acquired form) that diagnostic genetic testing becomes strongest and is most highly indicated. In accordance with the "Position Statement on Diagnosis and Treatment of Cardiac Amyloidosis" 6 of the Brazilian Society of Cardiology, it has been given a class I recommendation with level of evidence B, based on the findings of the Spanish study that estimated the prevalence of allelic variants in the TTR gene through analysis of large-scale sequencing data. 8 Among genetic aspects, another important point that has been increasingly underscored is the screening of presymptomatic patients.…”