The infundibulum (also known as ''conus arteriosus'') is a conical pouch formed from the upper and left angle of the

right ventricle A ventricle is one of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the upper ...

in the

chordate A chordate () is an animal of the phylum Chordata (). All chordates possess, at some point during their larval or adult stages, five synapomorphies, or primary physical characteristics, that distinguish them from all the other taxa. These fiv ...

heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...

, from which the

pulmonary trunk A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the ''main pulmonary artery'' or ''pulmonary trunk'' from the heart, and ...

arises. It develops from the

bulbus cordis The bulbus cordis (the bulb of the heart) is a part of the heart development, developing heart that lies ventral to the primitive ventricle after the heart assumes its S-shaped form. The superior end of the bulbus cordis is also called the conotrun ...

. Typically, the infundibulum refers to the corresponding internal structure, whereas the conus arteriosus refers to the external structure. Defects in infundibulum development can result in a heart condition known as

tetralogy of Fallot Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, is a congenital heart defect characterized by four specific cardiac defects. Classically, the four defects are: *pulmonary stenosis, which is narrowing of the exit from the ri ...

. A tendinous band extends upward from the right atrioventricular fibrous ring and connects the posterior surface of the infundibulum to the

aorta The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ...

. The infundibulum is the entrance from the right ventricle into the pulmonary artery and pulmonary trunk. The wall of the infundibulum is smooth.

Additional images

File:Gray490.png, Front view of

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

heart and lungs.

References

Cardiac anatomy {{circulatory-stub