Heart pt 1 Flashcards
Heart location
-Posterior to sternum between 2nd and 6th rib
The heart is rotated ___and the ____ half faces anteriorly.
Apex points ___ and ____.
Left, Right
Down, left
Mediastinum
Space in between lungs, heart located in the middle mediastinum
Pericardium
Two types of connective tissue sheaths around the heart
- Fibrous
- Serous
3 layers of the heart
- myocardium
- endocardium
- epicardium
Serous pericardium function
- Bursa reduces friction (lubricant in pericardial cavity)
- fist in a balloon model
Serious pericardium layers
- parietal layer: outter layer, adhered to inner surface of fibrous pericardium
- visceral layer: invests heart (also called epicardium
Fibrous pericardium
- thick layer of connective tissue that loosely surrounds heart
- adheres to sternum, diaphragm and parietal pleura (Long bursa)
Cardiac muscle
Myocardium
Myocardium 3 parts
- Bulbospiral muscle- wrings out heart
- pectinate muscle: thin atrial cardiac muscle fiber
- trabecular carneae: thick ventricle cardiac muscle fibers on inner surface
Endocardium
Connective tissue lining interior surface
Epicardium
Connective tissue adhered to exterior surface = visceral serous pericardium
Right heart transports
Deoxygenated venous blood to lungs
Left heart transports
Oxygenated blood from lungs to peripheral tissues
_____ and ______ maintain one way flow through heart
Atrioventricular (AV)
Semilunar valves
Tricuspid AV valve
Conducts blood from right atrium to right ventricle
Pulmonary valve
Conducts blood from right ventricle into pulmonary trunk/arteries
Bicuspid (mitral) AV valve
Conducts blood from the left atrium into left ventricle
Aortic valve
Conducts blood from left ventricle into aorta
Right atrium:
______ and ______ bring deoxygenated blood from body into atrium
Superior and inferior vena cava (SVC and IVC)
Right atrium:
Fossa ovalis
Site of foramen, a prenatal aperture that directs blood from right to left atrium
Right atrium:
_____ and _____ contract to push blood into ventricle
Pectinate muscles and vestigial auricle
Opening of coronary sinus located in _____
Right atrium
Right ventricle:
Tricuspid valve
- 3 cusps
- papillary muscles
- cordinae tendinae
- moderator band (part of bundle of His)
Right ventricle:
Trabeculae carnae
Dense smooth muscle bundles in wall
Right ventricle:
Pulmonary semi lunar valves
Guides blood out through pulmonary trunk
__ pulmonary veins bring oxygenated blood into the Left atrium
4
_____ atrium has thin walls and little Pectinate muscle
Left atrium
Location of left auricle
Left atrium
Left ventricle:
Bicuspid valve has
Two cusps and cordinea tendinae a attached to papillary muscles
Left ventricle:
Thick layer of ____ and _____
Myocardium and Trabeculae carnae
Left ventricle:
_____ guides blood through the aorta
Aortic semi lunar valve
Atrioventricular valves:
Held in place by _____ attached to ____
Chordae tendinae
Papillary muscles
Atrioventricular valves:
_____ separates cusps
_____ closes valves
Entry of blood
Ventricular contraction creates pressure that
Atrioventricular valves:
Papillary muscle contraction prevents
Eversion during systole
Stem from aortic sinuses and give off descending branches
Right and Left coronary arteries
Left coronary artery branches-
- left anterior descending (interventricular) artery
- circumflex artery (“anastomoses” with right coronary artery)
Anastomoses
where two arteries meet, allows for equal amount of blood flow through the region
Right coronary artery branches-
posterior descending (interventricular) -marginal (inferior margin of hear)
Ejection of blood from heart is _____ (contraction)
Filling of the heart is ______
- systole
- diastole
Systole valves and function
- atrioventricular valves: contraction increases blood pressure in ventricle, pushing cusps together to close valve
- semilunar valves: blood ejection pushes cusps aside
Diastole valves and function
- AV opens cusps
- Semilunar valves: retro flow from pulmonary trunk and aorta fills sinuses behind cusps and closes valve
First heart sound
Second heart sound
Lub= closure of AV valve Dub= closure of semilunar valve
Semilunar valve location
-base of pulmonary trunk and aorta
aortic/pulmonary sinuses:
spaces behind cusps of semilunar valve which catch blood during diastole
what creates sound of the heart
turbulence, collision of fluids
enlarged heart is a compensation for
blood not being properly ejected
Coronary vein (below) parallels ______ artery
Great cardiac-
Middle cardiac parallels-
Small cardiac parallels-
- anterior descending
- posterior descending
- marginal
What drains most of the coronary blood into the right atrium
coronary sinus
coronary blood perfusion occurs during
diastole as the semilunar valves close
coronary atherosclerosis
atherosclerotic plaques reduce blood flow and deprive tissue of oxygen downstream from blockage
collateral circulation in the heart
gradual ischemia induce formation of collateral arteries that compensate for coronary artery occlusion
increased collusion = decreased ability to compensate
treatment for blocked coronary arteries
- coronary bypass: inserting a shunt from aorta to affected area beyond occlusion
- -sections for repair taken from saphenous leg veins for small arteries
- -internal thoracic arteris repair larger arteries
- angio plasty
angina pecotris
“a strangling feeling in the chest”
not enough blood to tissues which accelerates heart and drives more blood through the already occluded system
angina symptoms
pain pressure heaviness tightness squeezing burning choking assoc. with lack of oxygen precipitated by emotional stress or exertion
angina treatment
vasodilate arteries
reduce load of heart
angina referred pain
produced by sensation of somatic sensory pathways co-localized with heart pain pathways at same levels of spinal cord
CT Angiography
series of X-rays used to mathematically reconstruct the inner densities of an organ with 3D image
clear picture of soft internal structures
Echocardiogram
sonogram of heart, ultrasound images to assess blood flow
