12.1 A Part 2 Flashcards
In words what is arterial diastolic pressure?
the pressure in the aorta and systemic arteries at the time of opening of the aortic valve
In words what is end diastolic pressure?
the pressure in the ventricle at the end of diastole
Arterial diastolic pressure has a value of roughly what?
80 mm Hg
End diastolic pressure usually sits at about how many mm Hg?
0-10 mm Hg
What is an S3 heart sound?
the sound of the ventricle wall vibrating from rapid ventricular filling, usually because of ventricular hypertrophy
What is an S4 heart sound?
occurs during atrial contraction due to vibration of the mitral or tricuspid valve leaflets as blood flows into the ventricle, usually due to atrial hypertrophy
Atrial hypertrophy will commonly result in what additional heart sound?
S4
Ventricular hypertrophy will commonly result in what additional heart sound?
S3
What is the venous a wave?
an increase in right atrial pressure produced by atrial contraction near the end of diastole
What is the venous c wave?
a slight increase in right atrial pressure that results from bulging of the tricuspid valve into the right atrium during ventricular contraction
What is the venous v wave?
a gradual rise in right atrial pressure due to atrial filling by venous return during ventricular systole
Why is there physiological splitting of S2?
- inspiration increases chest cavity volume, lowering atrial pressure
- this increases venous return to the right heart
- the right ventricle becomes more filled
- right stroke volume increases
- the time for ejection increases
- causes delayed closure of the pulmonic valve
Wide splitting of S2 is characterized by what changes?
an increase in the A/P split during expiration and even more so during inspiration
Wide splitting of S2 occurs when what occurs?
- prolonged right ventricle ejection
- due to right bundle branch block or pulmonic stenosis
How does a right bundle branch block cause wide S2 splitting?
the slower depolarization of the right ventricle prolongs ejection
How does pulmonic stenosis lead to wide S2 splitting?
the high resistance of a stiff pulmonic valve prolongs ejection from the right ventricle
What is paradoxical splitting of S2?
you can hear an S2 split during expiration in which the pulmonic valve closes before the aortic and no split during inspiration
What are two possible causes of paradoxical splitting?
left bundle branch block or aortic stenosis
Normal cardiac output has what range?
5 - 6 liters/minute
What is cardiac index?
a way to normalize values for cardiac output based on body size
What is a normal cardiac index value?
2.6 - 4.2 liters/minute/square meter of body surface area
Which has a higher pressure typically, right or left atrium?
left atrium by just a little
Left atrial pressure usually has what range?
1 - 10 mm Hg
What is the range of left ventricular pressure during diastole?
3-12 mmHg