The cardiac system Flashcards
Where is the heart located in most veterinary species?
In the chest cavity
What is the function of the cardiovascular system?
To continuously pump blood around the animals body and as such allow blood to fulfill its functions
Name the 4 main chambers of the heart
The left atrium, the left ventricle, the right atrium and the right ventricle.
What is the name of the heart muscle
The myocardium
Starting at the lungs describe the order in which the blood flows through the chambers of the heart
Lungs -> Left Atrium -> Left Ventricle -> Body and Brain -> Right Atrium -> Right Ventricle -> Lungs.
What is the area in the heart that controls heart rate?
The sinoatrial node
What is the name of the part of the cardiac conduction system that slows conduction of electrical signals to the ventricles to allow atrial contraction to be completed?
The atrioventricular node
In which direction, apex to base or base to apex do the ventricles contract? Why?
Apex to base. Contraction occurs in this direction because it is the direction in which the blood must be pushed to leave the ventricles and enter the aorta or the pulmonary artery.
What is the name for the period during the cardiac cycle when the myocardium is working?
Systole
What is the name for the period during the cardiac cycle when the myocardium is relaxing?
Diastole
What is the role of the cardiac muscle cell in the SA node?
To automatically generate the electrical impulses that trigger each heartbeat.
What microscopic structures allow cardiac muscle cells to transmit electrical impulses to neighboring cells?
Gap junctions
What anatomical structures create the heart sounds?
The heart valves
What 2 abnormalities in heart valves create heart murmurs?
Insufficiency or an inability to close properly and stenosis or an abnormal narrowing.
What features of heart murmurs are used when describing them?
Their intensity, their timing during the cardiac cycle and the location of their point of maximum intensity.
What is the definition of cardiac output (CO)?
The volume of blood ejected from the left ventricle in a set period of time usually 1 minute.
What determines cardiac output?
Stroke volume (SV) multiplied by heart rate (HR).