Challenges in the approach to a patient with aortic stenosis and cardiac amyloidosis with ATTR mutation associated with negative scintigraphy - A case report oleh Gabriela Carvalho Monnerat Magalhães, Luciana Coutinho Bezerra, Beny Binensztok, Maysa Ramos Vilela, Ellen Fernanda das Neves Braga, Adriana Soares Xavier de Brito, Gabriel Cordeiro Camargo, Luiz Felipe Camillis, Helena Cramer Veiga Rey, Clara Weksler