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Flashcards in The cardiac cycle Deck (25):

What occurs during the Diastole phase?

The heart ventricles are relaxed and the heart fills with blood.


What occurs during the Systole phase

The ventricles contract and pump blood out of the heart and to arteries.


What occurs during the 1st diastole period (late diastole)?

The atria and ventricles are relaxed and the atrioventricular valves are open.
- Oxygen-depleted blood returning to the heart from the body passes through the superior and inferior vena cava and flows to the right atrium.


What occurs during 2.Atrial systole?

Atrial contraction forces a small amount of additional blood into ventricles.


What occurs during 3.Isovolumic ventricular contraction?

First phase of ventricular contraction pushes AV valves closed but does not create enough pressure to open semilunar valves.


What occurs during 4.Ventricular ejection?

As ventricular pressure rises and exceeds pressure in the arteries, the semilunar valves open and blood is ejected.


What occurs during 5.Isovolumic ventricular relaxation?

As ventricles relax, pressure in ventricles falls, blood flows back into cusps of semilunar valves and snaps them closed.


What is systolic pressure?

Systolic pressure is the pressure of the blood in the arteries when the heart pumps.
- It is the higher of two blood pressure measurements.


What is diastolic pressure?

The diastolic pressure is specifically the minimum arterial pressure during relaxation and dilatation of the ventricles of the heart when the ventricles fill with blood.


What is the mean arterial pressure (MAP)?

The mean arterial pressure (MAP) is an average blood pressure in an individual during a single cardiac cycle.


What is pulse pressure?

Pulse pressure is the difference between the systolic and diastolic blood pressure.
- It is measured in millimeters of mercury (mmHg). It represents the force that the heart generates each time it contracts.


What is end diastolic volume (EDV)?

End-diastolic volume (EDV) is the volume of blood in the right and/or left ventricle at end load or filling in (diastole) or the amount of blood in the ventricles just before systole.
- Greater EDVs cause greater distention of the ventricle.


What is stroke volume?

Stroke volume (SV) is the volume of blood pumped from the left ventricle per beat


What is ejection fraction?

Ejection fraction (EF) is a measurement, expressed as a percentage, of how much blood the left ventricle pumps out with each contraction. -
- An ejection fraction of 60 percent means that 60 percent of the total amount of blood in the left ventricle is pushed out with each heartbeat.


What phase of the cardiac cycle and mechanical event is the a-wave?

- End diastole phase
- Atrial contraction


What phase of the cardiac cycle and mechanical event is the c-wave?

- Early systole phase
- Tricuspid bulging (IVC)


What phase of the cardiac cycle and mechanical event is the v-wave?

- Late systole phase
- systolic filling of the atrium.


What is phonocardiography?

Phonocardiography is the recording of all the sounds made by the heart during a cardiac cycle.
- Using the phonocardiogram.


Know how to interpret the pressure-volume loop



How are the 2 major sounds in phonocardiography caused?

- The first sound is caused by the closing of the mitral and tricuspid valves.
- The second is created by the closing of the aortic and pulmonic valves.


What is the interval between the two sounds in phonocardiography called?

A murmur


In phonocardiography when does normal contraction start?

When mitral & tricuspid valves closing


In phonocardiography when does normal contraction end?

When Aortic & pulmonary valves closing


What is stenosis?

Stenosis means the abnormal narrowing of a body channel.


What defects can be picked up on a phonocardiogram?

- Stenosis of aortic/pulmonary or regurgitation through mitral/tricuspid.
- Stenosis of mitral/tricuspid or regurgitation through aortic/pulmonary.
- Septal defect