Week 7 - Circulation Flashcards
Base of the heart is
the top
Apex of the heart is
the bottom - 5th intercostal space
Point of Maximal Impulse
Apex - because it touches the chest wall
Vein Characteristics
- low pressure
- use valves/muscles (to move blood)
- deoxy blood except for in pulmonary circuit
Artery Characteristics
- high pressure
- oxy blood except in pulmonary circuit
- Aorta is largest in body
Aneurysm
- a weak spot in the vessel which can rupture
- a bulge that can burst (dissection)
Causes
- unhealthy behaviours
- Hypertension
- smoking
- atherosclerosis
- high cholesterol
Coronary Sinus
is in the right atrium, is where de-oxy blood enters the right atrium from the myocardium
Coronary Arteries
- in the left aorta feed the myocardium during diastole
- after pumping blood out through the aorta, what is left over in top arch of aorta drops back down towards heart due to gravity. These arteries (located just above the semilunar valve) collect the blood and take it to the muscles of the heart
which ventricle is largest/strongest?
Left ventricle - pumps into systemic circulation (the body)
What controls/impacts heart beat?
Heart beats are controlled by the pacer (SA node) but can be impacted by the medulla oblongata (ANS control)
Atrial Kick
is the atrial contraction that occurs to help fill the ventricles
Lub
- S1
- AV closure
- End of diastole
Dub
- S2
- Semilunar valve closure
- End of Systole
Atrioventricular Valves (S_)
S1
- tricuspid
- mitral
Semilunar Valves (S_)
S2
- pulmonic
- aortic
Valves are repaired/replaced with:
Mechanical or biological
Mechanical Valve Repair
carbon and metal
lasts 20-30yrs, blood thinners
Biological Valve Repair
human donor (rare)
lasts 10-15yrs
often do not need blood thinner
typically cow tiss around heart or pig valve
Aortic Valve - Repaired or Replaced
Repair
Mitral Valve - Repaired or Replaced
Replaced
Myocardial pump
moves O2, nutrients, and other substances while eliminating wastes
Myocardial Blood Flow
Vena Cava
RV
RA
Lungs
LA
LV
Body
Diastole
ventricles relax and filling
120
Systole
ventricles contract and empty
Normal Diastole/Systole
120-139/80-89
Pulse Pressure
difference between systolic and diastolic
- 30-50
Starlings Law
the stretch ability of the heart
- says that when the muscle stretches there is going to be increased strength in the contraction
- this rule does not apply with heart disease leading to ineffective ventricular ejection and pooling or back-up
What happens with low BP
Sympathetic
vasoconstriction
increased CO
What happens with high BP
Parasympathetic (Vagus)
vasodilation
decreased CO
Endo
within or inner
Epi
above or surrounding
Myo
muscle
Cardium
cardiac
Endocardium
- regulates contractions, is smooth and non-adherent for blood flow
- also an elastic layer to help with contractions and a connective layer to attach to the muscle
Epicardium
- CT and fat: heart anchor and extra protection
- coronary arteries are situated here*
- innermost lay of the pericardium or visceral (closer to organ)
Myocardium
- contractions, this is where the coronary artery innervates to feed the heart muscle with O2
- told by the pacemaker to contract
Blood stem cell
an immature cell that can develop into all types of blood cells, including WBCs, RBCs, and platelets
Albumin
- produced by the liver
- helps to keep fluid in the vascular system
- major part of the protein in our blood
- prevents blood from seeping out of vessels
Lymphatic Sys
helps to absorb fats, and any extra fluids that may leak out of the cardiovasc sys
megaly
irregular enlargement
