semilunar valves


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Related to semilunar valves: cardiac cycle, tricuspid valve

semilunar valves

The crescent-shaped valves, each having three cusps, situated one at the beginning of the AORTA and the other at the origin of the PULMONARY ARTERY. These valves allow blood to flow only in a direction away from the heart.
References in periodicals archive ?
The back pressure of blood in the aorta against the heart's aortic semilunar valve is higher than that against the pulmonic semilunar valve of the pulmonary trunk.
The earliest anlage of the semilunar valves was first observed in 2.5 cm CVRL buffalo foetus in aorta (Figure 15) and pulmonary artery.
At early embryonic stages endocardial cushion tissue is positioned in the primitive AVC and OFT, which later on will contribute to formation of the TV and MV and Ao and PT semilunar valves. Some clinical studies argued that AV valve regurgitation is a common phenomenon during the first trimester of pregnancy [20].
A loud, single [S.sub.2] indicates pulmonary hypertension (with RV overload) or congenital heart disease involving the semilunar valves. Murmurs are graded 1-6/6, and are timed as early, middle or late systolic.
The semilunar valves are formed from three small tubercles of tissue that are (overriding), a small pulmonary outflow tract, and the inability of the ventricular septum to close.