Background: Persistent truncus arteriosus (TA) is a rare congenital heart condition with reported incidence of 1.2% among all congenital heart malformations. Majority of patients with TA die early in childhood due to complications such as heart failure.
Case presentation: An 18-year-old adult with unsuspected congenital heart disease since birth, not detected in childhood. Six months prior to his presentation, he complained of easy fatigability and paroxysmal nocturnal dyspnea. Chest radiography demonstrated normal heart size and electrocardiogram showed biventricular hypertrophy. Echocardiograph showed truncus arteriosus type II with large outlet ventricular septal defect. The patient was put on medical therapy including bed rest, fluid restriction and then surgical correction was done. The patient’s symptom improved after the surgical correction.
Conclusion: TA is a rare, serious congenital heart defect that can be detected in prenatal period by routine ultrasound screening. It is also very rare for TA to be silent and reach adulthood without clinical manifestation and a diagnosis.