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In the developing fetus, the ductus arteriosus (DA) is a shunt connecting the pulmonary artery to the aortic arch that allows much of the blood from the right ventricle to bypass the fetus' fluid-filled lungs. During fetal development, this shunt protects the lungs from being overworked and allows the right ventricle to strengthen. Fetus at eight weeks A fetus (alternatively foetus or fœtus) is an unborn human offspring from the end of the 8th week of pregnancy (when the major structures have formed) until birth. ...
In medicine, a shunt is a device designed to drain excess cerebrospinal fluid from the brain and carry it to other parts of the body. ...
The pulmonary arteries carry blood from the heart to the lungs. ...
The largest artery in the human body, the aorta originates from the left ventricle of the heart and brings oxygenated blood to all parts of the body in the systemic circulation. ...
Red blood cells (erythrocytes) are present in the blood and help carry oxygen to the rest of the cells in the body Blood is a circulating tissue composed of fluid plasma and cells (red blood cells, white blood cells, platelets). ...
In the heart, a ventricle is a chamber which collects blood from an atrium (another heart chamber) and pumps it out of the heart. ...
The heart with relation to the lungs (from an older edition of Grays Anatomy) This x-ray of the human chest shows the lungs as dark regions The lung is an organ belonging to the respiratory system and interfacing to the circulatory system of air-breathing vertebrates. ...
Closure at birth
When the newborn takes its first breath, pulmonary vascular resistance falls due to physical opening of the pulmonary capillaries and attenuation of intrauterine hypoxic pulmonary vasoconstriction. Decreased pulmonary vascular resistance increases pulmonary blood flow while pulmonary vascular pressure falls below aortic pressure. At the same time, the lungs release bradykinin and falling prostaglandin levels cause constriction of the smooth muscle in wall of the DA, reducing flow. Additionally, because of reduced pulmonary resistance, more blood flows from the pulmonary arteries to the lungs and thus the lungs deliver more oxygenated blood to the left heart. This further increases aortic pressure so that flow in DA may transiently reverse. Pressure is the application of force to a surface, and the concentration of that force in a given area. ...
Bradykinin is a physiologically and pharmacologically active peptide of the kinin group of proteins, consisting of nine amino acids. ...
A prostaglandin is any member of a group of lipid compounds that are derived from fatty acids and have important functions in the animal body. ...
Smooth muscle is a type of non-striated muscle, found within the walls of hollow organs; such as blood vessels, bladders, uteri. ...
General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ...
In normal newborns, the DA is closed within 15 hours after birth, and is completely sealed after three weeks. A nonfunctional vestige of the DA, called the ligamentum arteriosum, remains near the adult heart. The ligamentum arteriosum is a small ligament between the pulmonary artery and aortic trunk. ...
Patent ductus arteriosus Failure of a child's DA to close after birth results in a condition called patent ductus arteriosus. If left uncorrected, patency leads to pulmonary hypertension and possibly congestive heart failure and cardiac arrhythmias. Patent ductus arteriosus (PDA) is a congenital heart defect wherein a childs ductus arteriosus fails to close after birth. ...
In medicine, pulmonary hypertension (PH) or pulmonary artery hypertension (PAH) is an increase in blood pressure in the pulmonary artery or lung vasculature. ...
Congestive heart failure (CHF) (also called congestive cardiac failure and heart failure) is the inability of the heart to pump a sufficient amount of blood throughout the body, or requiring elevated filling pressures in order to pump effectively. ...
A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ...
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