Final answer:
Persistent truncus arteriosus is a congenital heart defect where the common arterial trunk fails to divide properly. This condition causes changes in blood flow and pressure, requiring surgical intervention to prevent complications.
Step-by-step explanation:
Persistent truncus arteriosus is a congenital heart defect in which the truncus arteriosus, the common arterial trunk that usually separates into the aorta and pulmonary artery, fails to divide properly. As a result, blood from both the systemic and pulmonary circulation mixes in the common arterial trunk. This leads to various hemodynamic changes, including increased blood flow to the lungs, increased pulmonary pressure, and increased workload on the left ventricle.
Without surgical intervention, persistent truncus arteriosus can lead to congestive heart failure and other complications. Treatment usually involves surgical repair to separate the aorta and pulmonary artery and close the ventricular septal defect.