Thrombophilia increases the risk of venous thrombosis, but is rarely responsible for aortic thrombosis. Aortic mural thrombus (AMT) may be associated with a protein C deficiency. However, it is necessary to determine whether the protein C deficiency is congenital/hereditary or secondary/acquired (consumption of protein C during the process of thrombus formation). This study describes a 77-year-old Japanese woman with incidentally diagnosed AMT, who had a protein C deficiency (activity 54%, antigen 42%). Sequencing of the protein C gene revealed a heterozygous mutation of c.1268delG, p.Gly423Valfs＊82 in exon 9, indicating a congenital protein C deficiency. These findings indicate that very late onset AMT can occur in an adult with congenital protein C deficiency.
Keywords: Aortic mural thrombosis; Congenital thrombophilia; Protein C deficiency.