The Heart (For Exam 3) Flashcards
What is included in the cardiovascular system?
heart and blood vessels
What part of the heart receives blood from the superior and inferior venae cavae, which receive deoxygenated blood from the upper and lower body?
the right atrium
The right ventricle pumps the deoxygenated blood to the lungs through the…
pulmonary trunk and arteries
The freshly-oxygenated blood is returned (from the lungs) to the heart by the _______, which empty into the _______.
pulmonary veins ; left atrium
The left ventricle pumps oxygenated blood to the upper and lower body (except for the lungs) through the…
aorta
What is included in the pulmonary circuit?
parts of the heart and the blood vessels that deliver the blood to the lungs and then returns into the heart (right ventricle, the pulmonary trunk, pulmonary arteries, pulmonary veins, and left atrium)
What is included in the systemic circuit?
parts of the heart and blood vessels that deliver blood to the body (not including the lungs) and returns it to the heart (left ventricle, aorta, superior vena cava, inferior vena cava, and right atrium)
Vein
any vessel bringing blood to the heart
Artery
any vessel that carries blood away from the heart
What is in the thoracic cavity?
heart and lungs
Mediastinum
space between the lungs
Where is the heart located?
behind the sternum with its apex pointing to the left at the 5th intercostal space
What is the diaphragmatic surface?
the part of the heart that rests on the diaphragm
What is the sternocostal surface?
the anterior surface of the heart
What parts of the heart are visible from an anterior view?
right atrium and right ventricle
What parts of the heart are visible from a posterior view?
left atrium and left ventricle
Pericardium
membranous sac enclosing the heart
- outer layer is fibrous connective tissue, attached around the base of the great vessels
- inner layer is lined with a serous membrane called parietal pericardium
Pericardial Space
space between the visceral and parietal pericardium
What are the “corners” of the heart?
L2
L5
R3
R4
Cardiac Tamponade
condition where excess fluid (such as blood) accumulates in the pericardial space and restrict filling of the chambers (and therefore ejection of blood from the heart)
Myocardium
- muscle of the heart
- thicker in ventricles than the atria
- covering on the outside by epicardium (serous membrane) and inside by endocardium (endothelium and connective tissue)
- rough appearance is ventricles is called trabeculae carneae
- striated bands in atria called pectinate muscle
The superior and inferior vena cava…
return venous blood from the body (except for the lungs) to the right atrium
The pulmonary trunk…
delivers blood from the right ventricle to the lungs
Four pulmonary veins carry blood from the ______ to the _____.
lungs ; left atrium
The aorta carries blood from the left ventricle to…
all of the tissues of the body (except for the lungs)
Do the atria contract at the same time?
yes
While the ventricles contract, the atria…
relax to refill
What makes up the cusps of the valves in the heart?
reflections of endocardium
Where are atrioventricular valves located?
between the atria and their respective ventricle
The right atrioventricular valve has ____ cusps and is called the _________ valve.
3 ; tricuspid
The left atrioventricular valve has ___ cusps and is called the ______ (or mitral) valve
2 ; bicuspid
As the ventricles contract, the increased pressure causes the flaps of the valves to…
close
The cusps of the atrioventricular valves have _______ attached to _______
chordae tendinae ; papillary muscles
The papillary muscles contract with the ventricular wall and pull the chordae tendinae taught to…
prevent the valve from prolapsing into the atrium
During contraction of the ventricles, blood is pumped into the…
pulmonary trunk and aorta
During relaxation of the ventricles, blood is…
prevented from returning to them by the semilunar valves
Where is the pulmonary semilunar valve located?
between the right ventricle and pulmonary trunk
Where is the aortic semilunar valve located?
between the left ventricle and aorta
What happens during ventricular contraction (systole)?
antrioventricular valves close and semilunar valves open
What happens during ventricular relaxation (diastole)?
atrioventricular valves open and semilunar valves close
The right and left coronary artery arise from the base of the…
aorta, just above the aortic semilunar valve
What does the right and left coronary artery do?
supply oxygenated blood to the myocardium
When do the right and left coronary arteries fill?
during relaxation of the ventricles
Are the coronary arteries under low or high pressure?
low
- this allows us to replace coronary arteries with veins
The right coronary artery gives off the __________ and then travels to the back of the heart to descend as the ________.
right marginal artery ; posterior interventricular artery
The left coronary divides into the ________ and __________.
anterior interventricular artery ; circumflex artery
The circumflex artery courses around to the back of the heart (in the atrioventricular sulcus) and provides branches to the…
left ventricle
Cardiac veins carry deoxygenated blood from the…
myocardium
The great cardiac vein runs with the…
anterior interventricular artery
The middle cardiac vein runs with the…
posterior interventricular artery
The small cardiac vein runs with the…
right marginal artery
The veins all empty into the…
coronary sinu
Where is the coronary sinus?
between the left atrium and left ventricle on the posterior heart
The coronary sinus opens into the…
right atrium
The anterior interventricular artery is also called the…
descending branch
Congestive Heart Failure
decreased pumping efficiency, heart enlarges
Arrhythmia
abnormal heart rhythm
Atrial Fibrillation
random firing in the atria
- can cause clots, stroke
Ventricular Fibrillation
random firing in the ventricles
- can cause cardiac arrest
Myocardial Infarction
heart attack, due to lack of blood supply to the myocardium
Heart Murmur
abnormal heart sounds caused by faulty valve(s)
Cardiomegaly
enlargement of the heart
Atherosclerosis
narrowing of arteries due to plaque (fatty deposits)
- increases peripheral resistance
Pericarditis
inflammation of the pericardium caused by a virus or bacteria
Tachycardia
high heart rate
Bradycardia
low heart rate
Atrial Septal Defect
when the opening between the left and right atrium (foramen ovale) doesn’t close after birth
Angina Pectoris
chest pain
Hypertrophic Cardiomyopathy
myocardium thickens due to increased pressure
- the ventricle has to pump against increased peripheral resistance, leading to the thickening
Dilated Cardiomyopathy
ventricular wall distends due to reduced ejection of blood from high peripheral resistance
- can lead to heart failure
What does it mean that the heart exhibits autorhythmicity?
it beats itself
Specialized cardiac muscle cells, collectively called the conducting system, spreads impulses through the…
myocardium
The heartbeat is initiated by a group of specialized cells called the _________, near the superior vena cava.
sinoatrial (SA) node
The SA node is also known as the…
pacemaker
The SA node depolarizes how many beats per minute?
72
What is the flow of electrical impulses through the heart?
- SA node
- AV node
- AV bundle
- left and right bundle branches
- Purkinje fibers
What does the vagus nerve do to the heart rate?
decreases it
Turbulence in the heart can lead to…
stroke due to clotting
Aneurysm
dilation within an artery that can cause stroke, bleeding if it bursts
- prevent by reducing athersclerosis
Fascia Adherens (Desmosomes)
help bind adjacent cells together and help transmit the contractile force to adjacent cells
Gap Junctions
allow ions to pass between cells, allowing transmission of impulse to spread through network of cardiac muscle cells (to help entire chamber contract at the same time)
Cardiac Cycle
time from the start of one heartbeat to the initiation of the next
Steps in the Cardiac Cycle
- atrial systole
- early ventricular systole
- late ventricular systole
- early ventricular diastole
- late ventricular diastole
Atrial Systole
contraction of the atria initiated by the SA node, causing the ventricles to fill
Early Ventricular Systole
atria relax and ventricles begin contracting, causing the AV valves to close (“lub”)
Late Ventricular Systole
continued contraction of the ventricles cause the semilunar valves to open and blood is ejected into the arterial trunks (the atria are still relaxed)
Early Ventricular Diastole
the ventricles begin to relax and the semilunar valves close to prevent blood from back-flowing into the ventricles (“dub”)
Late Ventricular Diastole
continued relaxation of ventricles causes AV valves to open and atrial contractions fill ventricles
