Date post: | 07-Mar-2016 |
Category: |
Documents |
Upload: | hc-communications |
View: | 214 times |
Download: | 0 times |
The Cardiovascular System-The Heart
Chapter 15
Objective 1 Describe the location of the heart and
the structure and functions of the pericardium.
Figure 15.1
Question 1 Your heart is found in the thoracic
cavity with 2/3 of its mass lying to the left of the body’s midline.
Question 2 The apex of the heart is formed by
the left ventricle and it rests on the diaphragm.
Question 3 The major blood vessels enter and
exit from the base of the heart.
Figure 15.2, Question 4 Explain cardiac tamponade.
Because the pericardium cannot stretch, fluid builds up and compresses the heart
Objective 2 Describe the layers of the heart wall
and the chambers of the heart
Question 5 Name the three layers of the heart
wall. Epicardium (external) Myocardium (middle) Endocardium (inner)
Question 6 Name the four chambers of the heart
Left atrium Right atrium Left ventricle Right ventricle
Question 7 Figure 15.3
Objective 4 Describe the structure and functions
of the valves of the heart.
Question 8 The atrioventricular (AV) valves on
the right side are also known as the tricuspid valve.
Question 9 What is the purpose of the chordae
tendineae? To prevent the valves from pushing up
into the atria.
Figure 15.4 Question 10- The AV valves on the left
side are known as the bicuspid or mitral valve.
Question 11 Define valvular heart disease.
Any condition in which one or more of the heart valves operate improperly.
Question 12 What happens if regurgitation
continues? This leads to congestive heart failure The heart can no longer pump enough to
supply the oxygen demands of the body
Objective 5, Figure 15.5 Explain how blood flows through the
heart.
Objective 6 Describe the clinical importance of
the blood supply of the heart.
Question 13 Name the two coronary arteries and
the name of the one vein. Left and right coronary arteries The vein is the coronary sinus
Question 14. Define the following: Ischemia Angina pectoris Myocardial infarction infarction
Ischemia- local anemia due to obstruction of blood vessels.
Angina Pectoris- ischemia of the myocardium, this causes chest pain.
Myocardial infarction- a heart attack. Infarction- Death of an area of tissue
because of interrupted blood supply. (A blood clot in the coronary arteries could cause this)
Objective 7 Explain how each heartbeat is
initiated and maintained.
Question 15, Figure 15.6, p. 359 List the five steps for the conduction
system of the heart SA Node Action potential AV Node AV Bundle Right and left bundle to branches Purkinje fibers
Question 16 List five triggers of ectopic activity
(ectopic pacemaker). Caffeine Nicotine Electrolyte imbalances Hypoxia Toxic reactions to drugs
Objective 8 Describe the meaning and diagnostic
value of an electrocardiogram, ECG.
Objective 9 Describe the phases of the cardiac
cycle.
Question 17 Define
Systole-contraction (PQRS) Diastole- phase of relaxation (T wave)
Question 18 List the three stages of the cardiac
cycle. Atrial systole Ventricular systole Relaxation period
P wave- atria depolarize, atria contract
QRS Complex- ventricles depolarize, ventricles contract
T wave-ventricles repolarize
Question 19 What causes heart sounds? Explain
lubb and dupp. Turbulence in blood flow created by
closure of the valves causes heart sounds.
Lubb- AV valves close, ventricles contract
Dupp- seimlunar valves close
Question 21 Explain mitral stenosis and mitral
valve prolapse (MVP). Mitral stenosis- narrowing of the mitral
valve by scar formation or congenital defect.
MVP- a portion of the mitral valve is pushed too far and the cusps do not close properly. About 10% of healthy people have this.
Objective 10 Define cardiac output, explain how it
is calculated and describe how it is regulated.
Question 22 How do you calculate cardiac output?
Stroke volume X beats per minute
Question 23 What is normal stroke volume for a
resting adult? 70 mL
Question 24 What is the normal heart rate in beats
per minute? 75 bpm 5.25L/min
Question 25 Name the three factors that regulate
stroke volume and ensure that the left and right ventricles pump equal volumes of blood. The degree of stretch in the heart before
it contracts. The forcefulness of individual ventricular
muscle fibers. The pressure required to eject blood
from the ventricles.
Question 26 Explain congestive heart failure
(CHF). The heart is a failing pump. More and more blood is left in the
ventricles at the end of each cycle. The heart stretches.
Question 27 Name the four causes of CHF.
Coronary artery disease Long term high blood pressure Myocardial infarctions Valve disorders
Omit Question 28.
Question 29 Explain how hormones and ions
regulate the heart rate. Epinephrine and norepinephrine enhance
the heart’s pumping effectiveness, increase heart rate and contraction force.
Thyroid hormones increase heart rate High K+ or Na+ decrease the heart rate
and contraction force.
Objective 11 Explain the relationship between
exercise and the heart.
Question 31 To benefit the heart aerobic exercise
must be for at least 20 minutes. How many times a week? 3-5
Question 32 What does sustained exercise do to
benefit the cardiovascular system? Increases the oxygen demand
Question 33A A. Explain coronary artery disease.
Atherosclerotic plaques in the coronary arteries reduce the blood flow to the myocardium.
Question 33B What are the risk factors?
High cholesterol High blood pressure Smoking Obesity Diabetes Type A Personality Sedentary lifestyle
Question 33C What are the treatment options?
Moderate exercise Reduce fat in the diet Drugs: nitroglycerine, beta blockers,
cholesterol lowering, clot dissolving Surgical and nonsurgical procedures to
increase blood supply to the heart
Question 34 Define atherosclerosis and its causes.
Large to medium-sized lesions High LDL levels Prolonged high blood pressure Carbon monoxide in cigarette smoke Cytomegalovirus (Herpes virus) Diabetes mellitus
Question 35 Explain the following congenital
defects. Patent ductus arteriosus Interventricular septal defect Valvular stenosis Tetralogy of Fallot
Question 35 Patent ductus arteriosus- the ductus
arteriosus between the aorta and pulmonary trunk remains open.
Interventricular septal defect- incomplete closure of the interventricular septum
Question 35 Valvular stenosis- narrowing of one of
the valves Tetralogy of Fallot- there are four
defects Interventricular septum defect An aorta from both ventricles instead of
just the left Narrowed pulmonary semilunar valve Enlarged right ventricle
Question 36 Define arrhythmia and name eight
causes Arrhythmia- an irregularity in heart
rhythm
Eight causes Caffeine Nicotine Alcohol Anxiety Drugs Hyperthyroidism Potassium deficiency Heart disease
Question 37 One serious arrhythmia is called heart
block (AV block)
Question 38 Define the following:a. Atrial flutter- rapid atrial contractions,
atrial rhythm averages 240-360 bpm.b. Atrial fibrillation- an uncoordinated
contraction of atrial muscles. They quiver individually instead of contract together.
Question 38c. Ventricular fibrillation- haphazard,
asynchronous ventricular muscle contractions. Circulatory failure and death occur.
Match the followingJ. 39. Sudden cardiac death- the
unexpected cessation of circulation and breathing due to heart disease.
A. 40. Cardiac angiography- A cardiac catheter is used to inject a radiopaque dye, clot dissolving drugs or tissue plasminogen activator (t-PA)
E. 41. Cor pulmonale (CP)- Right ventricular hypertrophy caused by hypertension (high blood pressure).
G. 42. Incompetent valve- any valve that does not close properly and permits backflow of blood.
D. 43. Cardiomegaly- Heart enlargement
B. 44. Cardiac arrest- A clinical term meaning cessation of an effective heartbeat. The heart may be completely stopped or in ventricular fibrillation.
I. 45. Paroxysmal tachycardia- A period of rapid heartbeats that begins and ends suddenly.
C. 46. Cardiac catheterization- 1. Procedure to visualize the heart’s
coronary arteries, chambers, valves and great vessels.
2. The flow of blood and oxygen can be measured
F. 47. Cardiac resuscitation- The artificial establishment of normal or near normal respiration and circulation. Follow the ABC’s. Airway, Breathing and Circulation.
H. 48. Palpitation- A fluttering of the heart or abnormal rate or rhythm of the heart.