Chapter 8 - Cardiovascular System Flashcards
What is a heart in the cardiovascular system
It is the pump
What is the function of the cardiovascular system
It carries the products of other systems
What is the vessels in the cardiovascular system
The transport tubes
What is blood in the cardiovascular system
Carries nutrients wastes and gases and hormones, defensive proteins and cells
Where is the heart located
In the thoracic cavity in the mediastinum. Area between lungs on top of diaphragm
What is the mediastinum
The inter-plural space
What surrounds the heart
Pericardium. Fibrous outer layer and double serous layer
Between which ribs is the heart located in dogs and cats
The third and seventh rib
Between which ribs is the heart located for horses and ruminants
Between the second and sixth rib
What are the layers of the heart
Pericardium myocardium and endocardium
What is endocardium made up of
Simple squamous epithelium
What is pericardial effusion
Abnormal accumulation of serous fluid between visceral and Parietal layers. Outer fibrous layer is not elastic, thus heart cannot fully explain during contractions. Pressure is relieved by aspiration of serous fluid.
Describe the systemic circulation of blood
Blood flow between heart and body tissues
Describe the pulmonary circulation blood flow
Blood flow between heart and lungs
Describe blood flow through the body
One-way flow through the heart and blood vessels. Valves in heart and veins prevent backflow
What is the function of the coronary vessels
Service the heart tissue, located on external surface. Can be considered part of systemic circulation
What is a systole
A cardiac contraction
What is a diastole
Cardiac relaxation
What are auricles
Flaps of the atria
What are coronary vessels
Vessels that service heart tissue
What is the interval ventricular sulcus
It separates the ventricles
What is the coronary sulcus
Separates atriums
Which side is the tricuspid valve for the heart best auscultated on
The right side
Describe the hearts location
The apex Curves caudally
Describe the blood delivery system
The heart to the artery to the arteriole to the capillary to the venule to the vein to the heart
What do arteries do
Carry blood away from the heart. Oxygenated except for pulmonary circulation and umbilical vessels of fetus
What to capillaries do
Contact tissue cells. Directly serve cellular needs. Site of diffusion
What do veins do
Carry deoxygenated blood toward heart
What is the lumen (in blood vessel)
Central blood containing space
How many layers does the lumen have
Three layers in the walls of arteries and veins. Smooth muscle, connective tissue and endothelium
Where are the capillaries located in the lumen
In the endothelium only
Describe arteries
Blood under higher pressure. Thicker walls more elastic fibers and smooth muscle
Describe veins
Blood under lower pressure. Valves prevent backflow skeletal muscles help push blood
Describe capillaries
Found in all tissue except for cartilage, epithelia, cornea and lens of Eye. ligaments and tendons are poorly vascularized. Provide direct access to almost every cell
What are the functions of capillaries
Exchange of gasses, nutrients, waste, hormones, defense.
Describe fetal circulation
The placenta is an organ of gas, nutrients, waste, exchange thus blood flow to the kidneys and lungs from G.I. tract is minimal
Describe the umbilical cord
Vein carries oxygenated blood flow from placenta to fetus via the ductus venosus. Arteries carry deoxygenated blood from fetus to placenta. Blood entering the right atrium can bypass lungs by the foreman ovale or ductus arteriosus.
What is pda
Patent ductus arteriosus. Vessel. Does not close afterbirth causing in adequate oxygenation. Most common congenital heart problem and dogs
What are the clinical signs of PDA
Shortness of breath, coughing, general weakness, exercise intolerance
How do you diagnose PDA
Auscultation for a murmur or an electro cardiogram
What is the treatment for PDA
Surgically close the ductus arteriosus
What are the signs of persistent right aortic arch condition
During normal fetal development or changes in the blood vessels. This vascular ring should’ve disappeared prior to birth it remains constricting the esophagus in the area dorsal to the heart.
What is it called when the esophagus is constricted between the ligamentum arteriosum and the aorta
PRAA
What is in atrial systole
The contraction of the atria. Blood moves from atria to the ventricles
What is a Ventricular systole
The contraction of ventricles. Blood moves from ventricles to arteries
What is an atrial diastole
The relaxation of the atria. Atria refills with blood
What is a ventricular diastole
The relaxation of ventricles. Ventricles begin to refill with blood
What is the lub sound mean
The closing of the AV valves. Mitral valve is best heard on the left side. Tricuspid valve is best heard on the right side
What is the dup sound mean
The closing of the semilunar valve. Both pulmonary and aortic valve’s best heard on left side
How does the heart conduct
Cardiac muscles able to generate its own electrical impulse to signal contraction
What does the sinoatrial node do
Initiates heart beat by depolarizing the cells. Depolarization and eventual repolarization continue throughout the heart.
What is the order of cardiac conduction
The SA node to the AV node to the AV bundles to the purkinje fibers
How do you measure cardiac conduction
Measured by an electrocardiogram
Why is there a delay between the depolarization of the SA node and the AV node
So the atrium can fill with blood
What does an electrocardiogram do
It measures cardiac electrical activity to depolarization and repolarization
What is the cardiac output
Amount of blood that leaves the heart. Cardiac output is equal to heart rate plus stroke volume
What is the heart rate dependent on
The rate of SA node depolarization. The cardiac output is influenced by exercise, autonomic nervous system and blood pressure
Describe digital pulses in horses
Normally the pulse is weak. If there’s a significant problem in the foot such as abscess or laminitis pulse will be stronger due to constriction of vessels in foot
What does afferent mean
Sends signal towards an organ
What does efferent mean
Sends a signal away from an organ
What is mitral valve disease
Mitral valve doesn’t close properly. Causes endocarditis or endocardiosis, ruptured cordae tendinae. Endocardiosis is most common in small dogs. Can lead to pulmonary edema and congestive heart failure
What is congestive heart failure
Progressive disorder due to problems with blood flow through heart. Blood backs up. Right side causes ascites and left causes pulmonary edema
