When arrhythmia hides a tumor: a case of atrial fibrillation unmasking superior vena cava syndrome. Emergency Care Journal, [S. l.], v. 21, n. 4, 2025. DOI: 10.4081/ecj.2025.13961. Disponível em: https://www.pagepressjournals.org/ecj/article/view/13961. Acesso em: 6 jun. 2026.