Cardiovascular system

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Cardiovascular
system
(simplified)
Καρδιαγγειακό
σύστημα
(απλοποιημένο)
the circulatory system, also known as the
cardiovascular system
What is it?

The circulatory system is a vast network
of organs and vessels that is responsible
for the flow of blood, nutrients,
hormones, oxygen and other gases to and
from cells. Without the circulatory
system, the body would not be able to
fight disease or maintain a stable internal
environment — such as proper
temperature and pH — known as
homeostasis (ομοιόσταση/ Η ικανότητα
του οργανισμού να διατηρεί το εσωτερικό
του περιβάλλον σταθερό ανεξάρτητα από
τις συνθήκες του εξωτερικού
περιβάλλοντος ).
Three independent systems that
work together
Many view the circulatory system (also
known as the cardiovascular system) as
simply a highway for blood. Yet, it is made
up of three independent systems that
work together according to the US
National Library of Medicine (NLM):
1. the heart (cardiovascular);
2. lungs (pulmonary);
3. arteries, veins, coronary and portal
vessels (systemic/ συστημικός =
affecting an entire system).
The heart
The heart is a muscular organ in humans and other animals, which pumps
blood containing oxygen and nutrients through a network of blood vessels
to all parts of the body.
Blood passes through the heart twice.
What?
In
humans, other mammals, and birds, the
heart is divided into four chambers:
upper
and
left and right atria;
lower left and right ventricles.
Commonly the right atrium and ventricle are
referred together as the right heart and
their left counterparts as the left heart.

In a healthy heart blood flows one way
through the heart due to heart valves,
which prevent backflow.[3]

The heart is enclosed in a protective sac,
the pericardium, which also contains a
small amount of fluid.

The wall of the heart is made up of three
layers:
1.epicardium,
2.myocardium,
3.endocardium.
Muscle tissue

The myocardium is the muscle
tissue of the heart, and forms a
thick middle layer between the
outer epicardium layer (tissue) and
the inner endocardium layer
(tissue).

Cardiac muscle cells, unlike most
other tissues in the body, rely on an
available blood and electrical supply
to deliver oxygen and nutrients and
remove waste products such as
carbon dioxide. The coronary
arteries help fulfill this function.
Protected
The pericardium (from the Greek
περί, and κάρδιον,) is a doublewalled sac containing the heart
and the roots of the great vessels.
The pericardial sac has two layers,
a serous layer (ορογόνος
υμένας/στρώμα) and a fibrous
(ινώδες) layer. It encloses the
pericardial cavity (κοιλότητα)
which contains pericardial fluid.
The pericardium gives protection
against infection, and provides the
lubrication (λίπανση) for the
heart.
Valves
With the atria and major vessels removed, all four valves are clearly visible
Ventricles (κοιλίες)
right and left ventricles, from above
Where?
The heart is located in the
middle compartment of the
mediastinum (μεσοθωράκιο) in
the chest (the central
compartment of the thoracic
cavity).
The muscle mass is greater on the left
side and the apex (κορυφή) of the heart is
pointed slightly to the left.
How?
Blood low in oxygen from the
systemic circulation enters the
right atrium from the superior and
inferior vena cavae and passes to
the right ventricle. From here it is
pumped into the pulmonary
circulation, through the lungs
where it receives oxygen and gives
off carbon dioxide. Oxygenated
blood then returns to the left
atrium, passes through the left
ventricle and is pumped out
through the aorta to the systemic
circulation−where the oxygen is
used and metabolized to carbon
dioxide. In addition, the blood
carries nutrients from the liver and
gastrointestinal tract to various
organs of the body, while
transporting waste to the liver and
kidneys.
Iconic symbol
The stethoscope is used for auscultation (ακρόαση) of the heart, and is one of the
most iconic (εμβληματικός ) symbols for medicine. A number of diseases can be
detected primarily by listening for heart murmurs (φύσημα).
3D echocardiogram
3D echocardiogram showing the mitral valve (right), tricuspid and mitral valves
(top left) and aortic valve (top right). The closure of the heart valves causes the
heart sounds.
Angina /ændʒənə/ (Στηθάγχη)

Angina pectoris, commonly known as
angina, is the sensation of chest pain,
pressure, or squeezing (ζούλιγμα), a
sudden intense pain in the chest, often
accompanied by feelings of suffocation,
caused by momentary lack of adequate
blood supply to the heart muscle.

The term derives from the Latin angere
("to strangle") and pectus ("chest"), and
can therefore be translated as "a
strangling (πνίγομαι, στραγγαλίζομαι)
feeling in the chest".
Diagram of discomfort caused by coronary
artery disease. Pressure, fullness,
squeezing or pain in the center of the
chest. Can also feel discomfort in the
neck, jaw, shoulder, back or arm.
Atherosclerosis
Atherosclerosis is a condition affecting the circulatory system. If the coronary
arteries are affected angina pectoris (στηθάγχη) may result or at worse a heart
attack.
Veins

In the circulatory system, veins (from
the Latin vena) are blood vessels that
carry blood toward the heart. Most veins
carry deoxygenated blood from the
tissues back to the heart; exceptions are
the pulmonary (πνευμονικός) and
umbilical (ομφάλιος) veins, both of
which carry oxygenated blood to the
heart. In contrast to veins, arteries carry
blood away from the heart. Veins are
less muscular than arteries and are often
closer to the skin. There are valves in
most veins to prevent backflow.
Arteries

Arteries (from Greek ἀρτηρία
(artēria), meaning "windpipe,
artery") are blood vessels that
carry blood away from the
heart.

While most arteries carry
oxygenated blood, there are
two exceptions to this, the
pulmonary and the umbilical
arteries.
Vital
The circulatory system is vital for
sustaining life.
Its normal functioning is responsible
for
1. the delivery of oxygen and
nutrients to all cells,
2. the removal of carbon dioxide
and waste products,
3. the maintenance of optimum pH,
and
4. the circulation of proteins and
cells of the immune
(ανοσοποιητικό) system.
Βιβλιογραφία
 https://commons.wikimedia.org/wiki
 https://el.wikipedia.org/wiki
 http://www.wordreference.com
 http://www.thefreedictionary.com/angina
 http://www.hygeia.gr
 https://www.google.gr
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