ANATOMY: CARDIOVASCULAR Flashcards
Explain the pulmonary and systemic circulation
Pulmonary circulation is the portion of the cardiovascular systemwhich carries deoxygenated blood away from the heart, to the lungs, and returns oxygenated (oxygen-rich) blood back to the heart.
- Is the movement of blood from the heart to the lungs, and back to the heart again
- This type of circulation adds oxygen and removes carbon dioxide from the blood
Systemic circulation is the part of the cardiovascular system which carries oxygenated blood away from the heart to the body, and returns deoxygenated blood back to the heart.
- Is the circulation of blood between the heart and the body
- Brings blood to and from the cells
- Can be subdivided into
–Coronary circulation: supplies blood directly to the heart muscle
–Hepatic-portal circulation
–Cerebral circulation
Explain which blood vessel carries venous blood from the heart to the lungs.
Explain which vessel carries oxygenated blood from the lungs to the heart
The pulmonary artery carries deoxygenated blood from the right ventricle into the lungs for oxygenation.
The pulmonary veins carry oxygenated blood from the lungs into the left atrium to be returned to systemic circulation.
State the number of pulmonary veins entering the heart.
Two pulmonary veins emerge from each lung hilum, receiving blood from three or four bronchial veins apiece and draining into the left atrium. An inferior and superior vein drains each lung, so there are four veins in total. The veins are fixed to the pericardium. The pulmonary veins travel alongside the pulmonary arteries.
State the functions of coronary circulation
Coronary circulation is the circulation of blood in the blood vessels of the heart muscle (myocardium). The vessels that deliver oxygen-rich blood to the myocardium are known as coronary arteries. The vessels that remove the deoxygenated blood from the heart muscle are known as cardiac veins. These include the great cardiac vein, the middle cardiac vein, the small cardiac vein and the anterior cardiac veins.
State the functions of hepatic portal circulation
Carries nutrients from the gastrointestinal tract to maintain glucose level in the body
How many pulmonary veins enter the heart?
4
What is the functin of the cerebral circulation?
move blood throught the brain
How much oxygen does the brain consume?
20%
10 secs w/o blood and your unconcious
How does venus blood drain from upper extremity?
path flow from upper limb to right atrium
What are the branches in the Aorta?
- Ascending between the heart and the aortic arch
- Aortic Arch
- Thoracic Aorta (Decending)
- Abdominal Aorta - below diaphragm to common iliac arteries (decending)
What are the major branchges of the Arch of Aorta?
- Right & Left Common cartoid artery
- Right & Left subclavian artery
- Brachiocephalic artery
What is the portal vein?
the main vessel in teh PV system & drains blood from the GI and spleen to the liver
How is the PV vein formed?
by confluence of the mesenteric & splenic veins, also recieves blood from inferiror mesenteric, gastirc and cystic veins
Where does the liver get blood supply?
Hepatic portal vein ~75% of liver blood & carries venious blood drained from spleen, GI track, and associated organs.
(oxygen poor and nutrient rich)
What is the Circle of Willis?
Anterior & Posterior communicating artery
Anteriror & Posterior cerebran artery
Basilar artery
Vertebral artery
Where does the liver get it’s oxygen?
The common hepatic artery is one of the final branches of the celiac artery. It supplies oxygen-rich blood to the liver, pylorus, pancreas, and duodenum.
The common hepatic artery splits into the proper hepatic artery and the gastroduodenal artery. The proper hepatic artery enters the porta hepatis where it splits into the left and right hepatic arteries that supply the liver.
What are the two major arteries of the brain?
Vertebral Artery
Internal Carotoid Artery
What is the mediastinum?
The central compartment of the thoracic cavity that contains the heart, great vessels, trachea, esophagus, thymus, thoracic duct, phreneic nerve, cardiac nerves and lymph.
It extends from the sternum to the vetebra column, the first rib to the diaphgram and between the lungs.
The heart is in the middle.
What is the pericardium?
membrane aroudn the heart and the roots of the great vessels
- Fibrous - tough outer layer of connective tissue
- Serous - thin layer
- Parietal layer: lines surface of fibrous
- Visceral layer (epicardium): adheres to heart
What is the pericardial cavity?
narrow space b/w the visceral and parietal layers of the serous pericardium and it contains a thin film of lubrication
What is pericardial effusion?
collection of excess fluid in the pericardial cavity
What forms the layers of the heart wall?
List the borders/margins of the heart
- right border: right atrium
- left border: left ventrical and left auricle
- inferior border: right ventricle and slightly left ventricle
- superior border: both atria
What are semilunar valves?
each of a pair of valves in the heart, at the bases of the aorta and the pulmonary artery, consisting of three cusps or flaps that prevent the flow of blood back into the heart
have 3 cusps shaped like half-moons
aortic and pulmonary valve
unlike AV valves, are not attached to the chordae tendinae
What are the atrioventricular valves?
two heart valves through which blood flows from the atria to the ventricles; prevents return of blood to the atrium
located b/w atrium and ventricle
tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, between the right atrium and the right ventricle
mitral valve is valve between the left atrium and the left ventricle of the heart, consisting of two tapered cusps
What is systole?
Systole is the contraction phase of the cardiac cycle (contrast with diastole) that results in the ejection of blood into an adjacent chamber or vessel
pulmonary/aortic semilunar valves are open
bicuspid/tricuspid mitral are closed
What is diastole?
Diastole, in the cardiac cycle, period of relaxation of the heart muscle, accompanied by the filling of the chambers with blood
pulmonary/aortic semilunar valves are closed
bicuspid/tricuspid mitral are open
How does the heart get arterial blood supply?
by two coronary arteries, right/left arise from the aortic sinuses in the initial portion of the ascending aorta and supply O2 blood to muslce and other tissues of the heart
What does the right coronary artery supply?
- right atrium and right ventricle
- sino-atrial & atrioventricular nodes
- interatiral septum
- a portion of the left atrium
- the posteroinferior 1/3 of the interventricular septum
- a portion of the posterior part of the left ventricle
What does the left coronary artery supply
- most of the left atrium & left ventricle
- anterior 2/3 of the interventricular septum
- the atrioventricular bundle and its branches
What is coronary artery disease?
develops when your coronary arteries — the major blood vessels that supply your heart with blood, oxygen and nutrients — become damaged or diseased.
What do cardiac veins do?
remove deoxgenated blood from the heart
What is the coronary sinus?
largest vein of the heart (drain to right atrium)
The coronary sinus accepts blood from where?
- great cardiac v
- middle cardiac v
- small cardiac v
NOT from anterior cardiac v (drains directly to right atrium)
What forms the cardiopulmonary nerve plexus of the heart?
Sympathetics:
Off chain T1-4, postganglionic, increase heart rate, dialate cardiac vessels
Parasympathetics:
Vegus CN X, preganglionic, decrease heart rate, constrict vessels
What does the conducting system of the heart do and what are the components?
specialized muscle fibers coordinate contractions of the heart chambers that give it an automatic rhythmic beat that initiate a normal heart beat.
The components:
- Sinoatrial node
- atrioventricular node
- atrioventricular bundle of His
- right and left bundle branches
- Purkinje fibers
What is the major arterial supply of the lower extremity?
femoral artery
The major venous drainage of the lower extremity are divided into what two groups?
-
Superficial: originates from the dorsal venous arch in the foot
- Great saphenous vein
- Small saphenous vein
-
Deep: generally follow the arteries
- major deep vein draining the lower limb is the femoral vein
- becomes the external iliac vein when it passes underneath the inguinal ligament to enter the abdomen
What are the major systemic veins?
- Superior vena cava
– carries de-oxygenated blood from the upper half of the body to the right atrium
– Formed by the right and left brachiocephalic veins
– The azygos vein joins it just before it enters the right atrium
- Inferior vena cava
– Carries de-oxygenated blood from the lower half of the body into the right atrium
– Formed by the union of the left and right common iliac veins
– Anastomoses with the azygos vein system (which runs on the right side of the vertebral column) and venous plexuses next to the spinal cord
What is the azygos vein and how is it formed?
The azygos vein is a vein running up the right side of the thoracic vertebral column draining itself towards the superior vena cava. It connects the systems of superior vena cava and inferior vena cava and can provide an alternative path for blood to the right atrium when either of the inferior venae cavae is blocked
The hemiazygos vein and the accessory hemiazygos vein are on the left
How is blood circulated in a fetus?
• Closure of the ductus arteriosus and foramen ovale
Oxygenated blood is shunted from the pulmonary system to the systemic circulation by two ways
– foramen ovale (fossa ovalis in adults)
– ductus arteriosus (ligamentum arteriosum in adults)
- Shunting allows for by- passing the pulmonary circulation
- The ductus venosus (ligamentum venosum in adults) shunts less than a third of the blood flow of the umbilical vein directly to the inferior vena cava
– Allows oxygenated blood from the placenta to bypass the liver
What structures define the posterior surface (the base) of the heart?
Posterior surface (base):
The posterior surface (base) of the heart is defined by the left atrium and a portion of the right atrium.
What are the 4 possible branches of the right coronary artery?
The right coronary artery (RCA) originates within the sinus of the right aortic cusp and is supplied by the ascending aorta.
The RCA travels in the coronary sulcus between RA and RV and passes around right border of heart between the posterior and diaphragmatic surfaces.
The RCA gives rise to the 4 branches below:
Marginal branch — The marginal branch arises from the RCA before it crosses the right border of the heart and travels along the acute margin just superior to the inferior border (see image); supplies the right ventricle.
Sinoatrial nodal artery (60% from proximal RCA, 40% from left circumflex artery (LCX)) — The sinoatrial nodal artery has a variable course of travel and can encircle the SVC either posteriorly or anteriorly; during posterior circling, the artery travels left of the SVC, circles around the posterior aspect of the vessel, and emerges anteriorly on the right side of the SVC to supply the SA node.
Posterior descending artery (PDA) — The posterior descending artery is also known as the posterior interventricular artery (PIV), emerges from the RCA after leaving the coronary sulcus and descends toward the apex of the heart (70% of population).
Atrioventricular nodal artery — The atrioventricular nodal artery supplies the AV node (90% of patients AV nodal artery, 10% LCX).
The artery that supplies the PDA is the structure that determines coronary dominance:
Right dominant — PDA is supplied by the RCA (85% of population)
Left dominant — PDA is supplied by the LCX (8% of population)
Co-dominant — PDA is supplied by both the RCA and LCX (7% of population)
