1. Department of General Surgery of Universitary Hospital and Clinics Hospital, University of São Paulo Medical School (FMUSP), 05403-000 São Paulo, SP, Brazil
2. Section of Vascular Surgery, Clinics Hospital, University of São Paulo Medical School (FMUSP), Avienda Dr. Enéas de Carvalho Aguiar 255, 05403-000 São Paulo, SP, Brazil