Physiology: Cardiac Cycle + Coronary Circulation Flashcards
- Is the following change in the pressure-volume loop due to
- increased contractility
- increased afterload
- or increased preload
increased preload
For the following valve, give the location, site of auscultation, and phase of the cardiac cycle when open
Pulmonic Valve
- B/W RV and pulmonary trunk
- Left 2nd intercostal at the the sternal border
- Open during systole
What is occurring at points A through D, in relation to the heart valves?
How do papillary muscles work?
- Contract when the ventricular walls contract.
-
They do not help the valves to close.
- Instead, they pull the vanes of the valves inward toward the ventricles to prevent their bulging too far backward toward the atria during ventricular contraction.
- Is the following change in the pressure-volume loop due to
- increased contractility
- increased afterload
- or increased preload
increased contractility
What is happening between 4 and 1 on the figure?
What is happening between 1 and 2 on the figure?
What is happening between 2 and 3 on the figure?
Label what is happening to the heart chambers A through G
- Coronary blood flow per gram of tissue is about 10 times the whole-body average.
- How is this high blood flow maintained?
- Despite the high blood flow, the myocardium must extract 65%–75% of the O2 to meet its needs. What does this do to the blood O2 content?
Where do the first and second heart sounds occur on this figure?
For the following valve, give the location, site of auscultation, and phase of the cardiac cycle when open
Aortic Valve
- B/W LV and aorta
- Right 2nd intercostal space at the sternal border
- Systole
What is happening between 3 and 4 on the figure?
For the following valve, give the location, site of auscultation, and phase of the cardiac cycle when open
Tricuspid Valve
- Between RA and RV
- Left 5th intercostal space at the sternal border
- Open during diastole
In the coronary circulation, what are the vasoactive metabolites and what are the mechanical effects of systole?
- Vasoactive metabolites
- Hypoxia
- Adenosine
- Mechanical effects of systole
- Compresses the coronary circulation
Compare the myocardial capillary density to the skeletal muscle capillary density? How does this difference affect diffusion and nutrient/gas exchange?
What heart sound does the following describe?
- MV and tricuspid valve closure; the MV closes before the tricuspid, so this sound may be split (but usually not discernible)
The first heart sound
- Is the following change in the pressure-volume loop due to
- increased contractility
- increased afterload
- or increased preload
increased afterload
In the coronary circulation, what is the most important control mechanism and what is the least important control mechanism?
- Most important:
- Local metabolic control
- Least important:
- Sympathetic control
For the following valve, give the location, site of auscultation, and phase of the cardiac cycle when open
Mitral Valve
- Between LA and LV
- Left 5th intercostal space at the midclavicular line
- Open during diastole
- About __% of coronary blood flow occurs during diastole at basal heart rates, so coronary perfusion is driven chiefly by ______ BP, not ______ pressure.
- About 80% of coronary blood flow occurs during diastole at basal heart rates, so coronary perfusion is driven chiefly by diastolic BP, not systolic pressure.
Label A through D
What heart sound does the following describe?
- Aortic and pulmonary valve closure; the AoV (A2) closes before the pulmonic valve (P2)); inspiration causes increased physiological splitting of this sound.
Second heart sound
