NHA EKG Technician Certification Exam Study Guide-Question and Answers-Complete solution guide-A+ Rated
NHA EKG Technician Certification Exam
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... [Show More] Guide-Question and AnswersComplete solution guide-A+ Rated
Where is the heart located?
in the thoracic cavity, between the lungs, in the mediastinum cavity, above
diaphragm, below sternum, in front of the spine
Which ventricle has a thicker wall?
left ventricle
What are the semilunar valves?
pulmonary and aortic
What are the atrioventricular valves?
tricuspid and bicuspid (mitral)
What supports the atrioventricular valves to help prevent back flow of blood?
chordae tendineae anchored to papillary muscles
What is the S1 sound?
"lub" and AV valves closing
What is the S2 sound?
"dub" and semilunar valves closing
What is systole?
when the ventricles contract and expel blood; between S1 and S2 beats
What is diastole?
when the ventricles relax and fill will blood; between S2 and the next S1
What is the blood flow through the heart?
vena cava, right atrium, tricuspid valve, right ventricle, pulmonic valve, pulmonary
artery, lungs, pulmonary veins, left atrium, bicuspid (mitral) valve, left ventricle,
aortic valve, aorta, arteries, arterioles, capillaries, venules, veins
What is the epicardium?
the outermost layer of the heart where coronary arteries run along; visceral layer of
pericardium
What is the myocardium?
the middle, thick, muscular layer of the heart that does the contracting; this is
damaged during an MI
What is the endocardium?
the innermost layer of the heart that lines the heart chambers, folds back on itself to
form heart valves, and is watertight to prevent leakage; the cardiac conduction
system is here
What is the pericardium?
the double-walled sac that encloses the heart with two layers, the visceral layer and
the parietal layer; it supports, protects, and anchors the heart to the diaphragm and
great vessels and a small amount of pericardial fluid is between the layers to
decrease friction
What is the superior vena cava?
a large vein that returns deoxygenated blood to the right atrium from the head,
neck, upper chest, and arms
What is the inferior vena cava?
a large vein the returns deoxygenated blood to the right atrium from the lower
chest, abdomen, and legs
What is the aorta?
the largest artery in the body that takes oxygenated blood from the left ventricle to
systemic circulation to feed all organs of the body
What are the five great vessels?
superior vena cava, inferior vena cava, pulmonary artery, pulmonary veins, aorta
What are the phases of diastole?
1. Rapid filling: atria is full of blood and high pressure, ventricles have just
emptied and low pressure, pressure difference causes AV valves to open and flow
from atria to ventricles; steady stream
2. Diastasis: the pressure in the atria and ventricles equalizes as blood flows to the
ventricles; blood flow slows
3. Atrial Kick: the last phase, atria empty and contract to squeeze all blood out,
high pressure in ventricles and low pressure in atria, AV valves pushed up and
slam shut; S1 heard at this phase, provides 15-30% of ventricular filling, heart
rhythm abnormalities in this phase result in decreased cardiac output
What are the phases of systole?
1. Isovolumetric contraction: ventricles full, but not full enough to open semilunar
valves, muscle contracts inward to increase pressure, no blood flow and valves are
still closed; greatest consumption of myocardial oxygen
2. Ventricular ejection: semilunar valves open, blood pours out of ventricles to
aorta and pulmonary artery, half of the blood empties fast, then blood flow slows
3. Protodiastole: blood flow slows as pressure in ventricles, aorta, and pulmonary
artery equalizes
4. Isovolumetric relaxation: ventricles relax and pressure is low, aorta and
pulmonary artery have high pressures, so semilunar valves slam shut; S2 sound
heard at this phase
What are the two kinds of heart cells?
contractile cells and conduction system cells
What part of the nervous system controls the heart? [Show Less]