Adult Echocardiography Practice Exam

Which structure serves as the outflow tract from the right ventricle to the lungs?

1. Infundibulum

2. Thebesian valve

3. Supraventricularis

4. Eustachian valve

The correct answer is: Infundibulum

The infundibulum, also known as the conus arteriosus, is the structure that serves as the outflow tract from the right ventricle to the pulmonary artery, leading to the lungs. Located at the superior part of the right ventricle, it aids in channeling blood smoothly from the ventricle into the pulmonary artery during systole. The muscular walls of the infundibulum help reduce turbulence and facilitate efficient blood flow into the pulmonary circulation. This anatomical arrangement is crucial for proper oxygenation of blood, which is then delivered throughout the body. The other structures mentioned do not function as outflow tracts from the right ventricle. The Thebesian valve is a small valve found at the entrance of the coronary sinus into the right atrium, involved in directing blood flow from the coronary veins. The supraventricularis typically refers to a concept related to atrial structures, and the Eustachian valve, which is rudimentary in adults, serves to direct blood from the inferior vena cava into the right atrium, not from the right ventricle to the lungs.