Mediastinum and heart Flashcards
Where is the mediastinum located?
Between the right and left lung
what are gap junctions?
specialized connections between each muscle fibers. if one cell is polarized, all the cells will polarize. this helps keep the heart synchronized
what node is known as the pacemaker node?
SA node
Where is the apex of the heart located?
left 5th intercostal space
what are the cardiac vessels?
veins: superior vena cava (low oxygen), pulmonary veins (high oxygen)
arteries: pulmonary trunk (low oxygen), ascending aorta, aortic arch
Structures of the RIGHT atrium
auricle, pectinate muscle, crista terminale (connection of two vena cava), fossa ovalis, openings of SVC and IVC, opening of coronary sinus, TRIcuspid valve
Structures of RIGHT ventricle
trabeculae carnae, papillary muscles with moderate band, chordae tendineae, tricuspid valve, pulmonary valves
structures of LEFT atrium
Auricle (smaller than R side), pectinate muscle, pulmonary veins, fossa ovalis, BIcuspid valve
structures of LEFT ventricle
trabeculae carnae, papillary muscle, bicuspid valve, chordae tendineae, aortic valve
what are the locations for valve auscilation?
aortic valve: R 2nd intercostal space
pulmonary valve: L 2nd intercostal space
tricuspid valve: L 5th intercostal space
mitral valve: L 5th intercostal space mid-clavicular line
what is the goal of pulmonary circulation?
gas exchange
What are the steps of pulmonary circulation?
RA through triscupsid vavle into RV into the pulmonary trunk to the R and L pulmonary arteries into the R and L lungs to the pulmonary veins and back to LA
What is the goal of systemic circulation?
delivery of oxygen and nutrients to the whole body
What are the steps of systemic circulation?
LA through bicuspid valve into the LV to the ascending aorta, aortic arch, descending aorta to the whole body
When do pulmonary and systemic circulation occur?
simultaneously
what is the cardiac cycle?
the beginning of one heart beat to the beginning of the next
What happens during diastole?
atrioventricular valves open and pulmonary/aortic valves close to allow the blood to drain to the ventricles
heart at rest
**coronary arteries are getting blood
What happens during systole?
pulmonary/ aortic valves open, atrioventricular valves close, atria contracts to push more blood into the ventricles, then ventricles contract to project the blood
Pathway of blood
1 deoxygenated blood comes into sup/ inf vena cave
2 goes into the RA
3 through tricuspid valve
4 into RV
5 through pulmonary valve
6 into pulmonary arteries
7 to the R and L lungs
8 into pulmonary veins
9 into LA
10 through bicuspid valve into LV
11 through aortic valve
12 into aorta
13 to the whole body
cardiac cycle
1 atrial systole
2 atrial diastole
3 ventricular systole part 1
4 ventricular systole part 2
5 ventricular diastole early
6 ventricular diastole late
conducting system
SA node to L/R atrial contraction to AV node to bundle of his to L/R bundle branches to purkinje fibers
Base HR of SA node
60-100 BPM
Base HR of AV node
40-60 BPM
Sympathetic innervation of the heart
increases HR T1-T4 cervical cardiac sympathetic n. and thoracic cardiac sympathetic n.
