The arteries are vessels whose walls
are formed by three layers (inner layer
or endothelium, middle layer and
outer layer or adventitia), with a
predominance of fibers muscle and
elastic fibers in the middle layer.
Cardiovascular system.
The cardiovascular system
consists of the heart and blood
vessels: arteries, veins and
capillaries.
Blood vessels.
They form a network of ducts that carry
blood from the heart to the tissues and
from the tissues to the heart.
Arterioles.
The arterioles are small arteries
whose function is to regulate the
flow to the capillaries.
Repolarization.
Recovering the resting membrane potential is due to the opening of potassium channels and the
closing of calcium channels.
Cardiac cycle.
A cardiac cycle includes all electrical
phenomena (action potential and its
propagation) and mechanical
(systole: contraction; diastole:
relaxation)
Preload or degree of stretching.
Of myocardial fibers during diastole
determines the strength of
myocardial contraction.
Afterload.
It is the pressure that must overcome
the ventricle during systole to open the
atrioventricular valves.
Heart Rate.
Is the number of times the heart
contracts in one minute (bpm). Proper
heart rate is essential for the proper
functioning of the heart.
Depolarization.
When excitation fibers sinus node arrives
to atrial fibers causes the rapid opening of
the sodium channels, which starts the
rapid depolarization.
Blood pressure.
Blood pressure is the hydrostatic
pressure of the blood against the
vessel wall containing it.
Cardiac output.
Is the amount of blood pumped by
the heart into the aorta each
minute.
Blood flow.
Is the volume of blood flowing through any
tissue per unit time (ml / min). The total
blood flow is the cardiac output.
Arterial anastomosis:
It is the union of two arterial
branches that supply the same
region.
Cardiac muscle.
Infarction or heart muscle consists of
striated muscle fibers shorter and less
circular than skeletal muscle fibers.
Arteriovenous anastomoses:
Is direct communication between an
artery and a venule so that no blood flows
through the capillary network.
Stroke volume
Is the volume of blood pumped
by a ventricle in shrinkage.
Anastomosis.
It is called anastomosis to
the union of two or more
vessels.
Plateau.
In a second phase, slow calcium channel that
open facilitate the entry of calcium ions into
myocardial fiber.
Vascular resistance.
Vascular resistance is the force that resists the
flow of blood, primarily as a result of this friction
against the vessel wall.