CV checklist 2 Flashcards
P wave
Atrial depolarization
QRS wave
ventricular depolarization
T wave
repolarization of ventricles
Heart block
any interruption of the conduction impulse pathway
the part of the conduction system that is most commonly involved in heart block?
AV node
why do the ventricles continue to contract even though the signal from the SA node is not getting down to the ventricles?
special areas in the ventricles may create electrical signals to cause the ventricles to contract. This natural backup system is slower than the normal heart rate and isn’t coordinated with the contraction of the atria.
the two divisions of the ANS and their neurotransmitter chemicals??
the sympathetic division and the parasympathetic division
HR
Heart rate
what effect does epinephrine have on the SA node
increases heart rate
what effect does acetylcholine have on the SA node?
It slows it down
Blood pressure difference between the left and right ventricles
The left ventricle is thicker and more muscular than the right ventricle because it pumps blood at a higher pressure. The right ventricle is triangular in shape and extends from the tricuspid valve in the right atrium to near the apex of the heart.
where is BP the lowest among systemic arteries and veins?
Vena Cava
where is BP the highest among systemic arteries and veins?
Aorta
which is capable of vasodilation and vasoconstriction? arteries, veins, or both arteries and veins?
both
what is the definition of the term arteriole
a small branch of an artery leading into capillaries.
–what is the major structural difference between large arteries and arterioles
large to medium size arteries are mostly elastic and arterioles are muscular
what are the two basic functions of arterioles?
Arterioles are under the control of the sympathetic nervous system, and constrict and dialate to regulate blood flow. The functions of arterioles include: Transport blood from arteries to capillaries. Arterioles are the main regulators of blood flow and pressure.
Outline the pathway of circulation through the systemic blood vessels:
–start this at the left ventricle and end at the right atrium
left ventricle -> aorta -> arteries (large and medium sized) -> arterioles -> capillaries -> venules -> veins -> Cr and Cd vena cavae -> right atrium
what is the purpose of the valves located on the inside of veins?
The valves function to keep blood moving in one direction. … When the muscle is at rest, the valves close helping to prevent the backward flow of blood.
are veins capable of vasoconstriction and vasodilation?
yes
what is normal blood pressure for the Cr and Cd vena cavae?
close to 0
CVP – what does this stand for?
central venuous pressure
are the vena cavae central veins or peripheral veins? what about the cephalic vein?
central
peripheral
List the factors that assist in the return of systemic venous blood to the heart
valves
contraction of skeletal muscle
peristalsis
contraction of the diaphragm? when the diaphragm contracts (during inspiration) pressure in the abdominal cavity goes up and pressure in the thorax goes down.
arterial pulsation
–
gravity
the are two aspects to evaluation of the arterial pulse
the are two aspects to evaluation of the arterial pulse:
1. Pulse rate per minute – this will always normally be equal to the heart rate
2. Strength of the pulse
Example: when an animal is in shock its pulse will usually be rapid and weak
how is both pulse rate and heart rate per minute usually calculated
Count the number of times you hear the heart beat when listening with a stethoscope or the number of times you feel the pulse beat when palpating an artery for 15 seconds then multiply this number by 4.
Arteries used for palpation of the pulse in the:
Cat and dog?
Horse?
Cow?
Dog: femoral artery
Horse: The external maxillary artery
Cow: facial artery
what is the function of capillaries
They bring nutrients and oxygen to tissues and remove waste products.
what is the function of the endothelial pores in the capillary wall
Their walls are very thin to allow substances to easily and quickly diffuse, or pass through them. Capillaries are much thinner than arteries and veins, because their walls are made up of only a single layer of endothelial cells, the flat cells that line all blood vessels.
describe the makeup of the capillary wall
Capillary walls are thin and are composed of endothelium (a type of simple squamous epithelial tissue). Oxygen, carbon dioxide, nutrients, and wastes are exchanged through the thin walls of the capillaries.
What is the formula for calculation of cardiac output? Stroke volume is part of this formula. What is stroke volume?
CO = SV x HR
