Cardiovascular Physiology Lab Flashcards
Electrocardiogram
The pattern of electrical activity recorded at the body surface
Blood enters the atrial chambers of the heart at a ________ pressure
low
Blood leaves the ventricles at a ______ pressure
high
What does the high atrial pressure provide?
The energy to force blood through the circulatory system.
Sinuatrial (SA) Node
A group of specialized muscle cells that act as a pacemaker for the heart. They rhythmically produce action potentials that spread through the muscle fibers of the atria. The resulting contraction pushes blood into the ventricles.
Atrioventricular (AV) Node
The only electrical connection between the atria and the ventricles.
Three phases of the cardiac action potential
Rapid depolarization
Plateau depolarization
Repolarization back to resting membrane potential
P-wave
produced by atrial depolarization
QRS Complex
produced by ventricular depolarization; atrial repolarization is also occuring during this time, but its contribution is insignificant
T-wave
produced by ventricular repolarization
Atrioventricular (AV) Valves
Prevent backflow from ventricle to atrium. Located between the atrium and ventricle on each side of the heart
Semilunar Valves
prevent backflow of blood from the aorta and pulmonary artery into the respective ventricle. located between the ventricle and the artery on each side of the heart.
ECG in resting volunteer (lab procedure)
You will record the ECG , analyze the signal and observe the effects of slight movement on the signal
ECG and heart sounds (lab procedure)
You will use a stethoscope to listen to the heart and an event marker to determine the relationship between what you are hearing and the ECG being recorded at the same time.
ECG and phonocardiography (lab procedure)
You will record the heart sounds (phonocardiogram) together with the ECG.
Aim of heart sounds lab
Examine the relationship between the ECG and the characteristic sounds of the heart
Cardiac Output (CO)
The volume of blood that the heart ejects into the circulation each minute. The product of the heart rate (beats/min) and the stroke volume (liters/beat).
Stroke volume (SV)
The volume of blood ejected during each beat. (averages at 5.0 liters/min.
The nervous system controls heart rate via _________
The autonomic nerves
What happens to the vagal activity and the sympathetic activity during exercise?
Vagal activity diminishes and sympathetic activity increases.
*This together with increased levels of circulating epinephrine, results in an increased heart rate.
ECG and volume pulse at rest (lab procedure)
You will measure the ECG and volume pulse from a resting volunteer
ECG and volume pulse after exercise ( lab procedure)
You will measure the ECG and volume pulse in a volunteer at intervals after exercise, analyze the resultant signals, and compare them with the volunteers resting ECG and volume pulse.
Volume pulse after hand exercise (lab procedure)
You will measure changes in the finger pulse in a volunteer at intervals after hand exercise, analyze the resultant signals, and compare them with volunteers resting finger pulse.
