PART 2 CARDIOVASCULAR SYSTEM Flashcards
four-chambered muscular organ approximately
the size of a fist. It is positioned in the mid-mediastinum of the
chest, behind the sternum
heart
Approximately two-thirds
of the heart lies to the left of the midline of the sternum between what ribs?
2nd and 6th ribs
The apex of the heart is formed by the
____________ and lies above the diaphragm at the level
of the _________ to the left
a.tip of the left ventricle
b.5th intercostal space
The base of the heart is
formed by the atria and projects to the right,___________. Posteriorly, the heart rests at the level of the ____________
a. lying below the 2nd rib
b.5th -8 thoracic vertebrae
Compressions must be done
at a depth of at least___________) for an average adult, avoiding excessive
chest-compression depths.
2 inches (5 cm
Externally, surface grooves called ______ the boundaries
of the heart chambers.
sulci mark
The heart is enclosed in a sac called
pericardium
Tough, loose-fitting and inelastic sac
surrounding the heart
Fibrous pericardium
Consisting of two layers:
Serous pericardium
Inner lining of the fibrous pericardium
parietal layer
Covering the outer surface
of the heart and great vessels
Visceral layer or epicardium
A thin layer of fluid called the __________ separates the
two layers of the serous pericardium.
pericardial fluid
abnormal amount of fluid can accumulate between the layers,
resulting in a
pericardial effusion
compresses the heart muscle, leading
to a serious decrease in blood flow to the body. This, ultimately,
may lead to shock and death.1,4
cardiac tamponade
The heart wall consists of three layers
(1) outer epicardium,
(2) middle myocardium, and (3) inner endocardium.
Support for the four interior chambers and valves of the heart
is provided by ___________, which form a
fibrous “skeleton.”
four atrioventricular (AV) rings
is the backflow of blood through a malfunctioning
leaky valve
REGURGITATION
is a pathologic narrowing or constriction
of a valve outlet, which causes blood to back up and
increased pressure in the proximal chamber and vessels
STENOSIS
______________
causes high resistance to the blood flow into the left ventricle from the left
atrium. This increased resistance causes a backflow into the pulmonary circulation,
leading to pulmonary edema with fluid collecting in the alveoli and interstitial
spaces in the lungs, impairing oxygenation and breathing.
Mitral stenosis
(decreased oxygen supply
Tissue Ischemia
Complete obstruction of a coronary
artery may cause tissue death or infarct, a condition called
Myocardial Infarction
___________ is the name given to three
types of coronary artery diseases (CAD) that are associated with
gradual and/or sudden obstruction of the coronary arteries
a. Acute Coronary Syndrome (ACS)
three
types of coronary artery diseases (CAD)
(1) unstable angina or angina pectoris, (2) Non-ST segment elevation myocardial infarction (NSTEMI) and (3) ST-segment
elevation myocardial infarction (STEMI).
Classic signs of tissue ischemia (decreased oxygen
supply) are chest pain and shortness of breath resulting in a clinical condition
called
angina pectoris
Symptoms of a _________ include tightness
or pain in the chest, neck, back or arms, as well as fatigue, lightheadedness,
abnormal heartbeat and anxiety. Women are more likely to have atypical
symptoms than men
myocardial infarction
Because
the thebesian veins bypass or shunt around the pulmonary circulation
as part of the normal anatomy, this phenomenon is
called an anatomic shunt.
a.thebesian veins
myocardial tissue possesses
the following four key properties:
- Excitability
- Inherent rhythmicity or automaticity
- Conductivity
- Contractility
is the ability of cells to respond to electrical,
chemical or mechanical stimulation
excitability
is the unique ability of
the cardiac muscle to initiate a spontaneous electrical impulse
(depolarization and repolarization).
Although such impulses can
arise from anywhere in the cardiac tissue. This ability is highly
developed in specialized areas called the _____________
a. Inherent rhytmicity or automaticity
b. heart pacemaker or nodal
tissues.