HRR: physiology of valve disease Flashcards
What is diastole?
AV valves are open and there is little resistance to flow, while SL valves are closed with no leakage.
What is systole?
AV valves are closed with no leakage and SL valves are open with little resistance to flow.
What is stenosis?
Obstruction to valve flow at a phase when the valve should be open; the pressure gradient serves as the hallmark.
What is regurgitation?
Inadequate valve closure leads to back flow.
Can a valve be both stenosis and regurgitant?
Yes.
What are the basic anatomical elements of the mitral valve?
Chordae tendinae, papillary muscles, anterior and posterior leaflets.
What is the main cause of mitral stenosis?
Rheumatic.
What are some signs of mitral stenosis?
SOB with exertion or laying down, fatigue, swollen feet or legs, palpitations, coughing up blood, chest pain, dizziness.
Describe some issues with mitral stenosis.
Increased LA pressure leads to pulmonary hypertension, and RV pressure overload can lead to RV hypertrophy, RV failure, tricuspid regurgitation, and systemic congestion.
What are some paradoxes of mitral stenosis?
The LV can be unaffected and pulmonary symptoms can diminish as the RV fails.
How does mitral stenosis impact preload?
It decreases it.
How will the pressure of the LA be impacted in mitral stenosis?
The pressure will be higher.
Mitral stenosis is a substrate for…
A fib.
What happens to a PV loop for the LV in mitral stenosis?
It shifts left due to lower volumes and has a slightly lower peak pressure. The curve will also narrow due to SV being decreased. The LVEDV is also decreased.
What are signs of mitral regurgitation?
Murmur, SOB with exertion or laying down, fatigue, swollen feet or ankles, excessive urination, cough.
What is the pathophysiology of mitral regurgitation?
The LA pressure is increased, and it is also dilated. The LV can also experience volume overload and dilate and experience eccentric hypertrophy. The process can lead to pulmonary hypertension, A fib, and low CO.
What happens to SV in mitral regurgitation?
It increases; there is a forward and a reverse SV.
A tall V wave is seen in…
Mitral regurgitation.
Mitral regurgitation is a substrate for…
A fib.
What happens to the PV loop in mitral regurgitation?
It’s huge. The isovolumetric relaxation and contraction are gone, giving it a blob appearance. SV increases due to an increase in LVEDV from excess being pumped in as regurgitation from the previous cycle. The peak pressure decreases as well.
What is the difference between compensated and decompensated mitral regurgitation?
In compensated, the body’s reflexes can account for the changes in the system. HR and systemic resistance will increase, creating bigger EDV and ESV than normal. This makes a large SV and EF. In decompensated, the body cannot overcome the issue. EDV is huge, but so is ESV and EF is low.
Describe left ventricle events in chronic decompensated mitral regurgitation.
- Increase in EDV and ESV
- Increase in wall stress and LV dilation
- LV dysfunction
- Decreased LV SV
- Lower EF.
Describe left atria events in chronic decompensated mitral regurgitation.
- Volume overload
- L dilation
- Increased pressure
- Pulmonary congestion
- Pulmonary HTN and dyspnea
- Congestive heart failure symptoms.
What are the cusps of the aortic valve?
Left, right, and posterior.
What will a congenital bicuspid aortic valve cause?
Aortic stenosis.
What are the main etiologies of aortic stenosis?
Degenerative calcification, congenital, and rheumatic.
What are some signs of aortic stenosis?
Murmur, chest pain, fatigue, palpitation, SOB, pulsus tardus.
Describe the pathophysiology of aortic stenosis.
LA pressure increases and it dilates. The LV has a volume overload, dilates, and undergoes eccentric hypertrophy. The LV can also experience concentric hypertrophy. Issues can include pulmonary hypertension, LA arrhythmia, and low CO.
What happens to LEDP in aortic stenosis?
It increases.
What happens to SV in aortic stenosis?
Reduced.
What happens to pulse pressure in aortic stenosis?
Reduced; this is because the systolic pressure decreases from less blood being ejected into the aorta, and the diastolic pressure increases due to reduced compliance. a decrease in systolic and increase in diasotlic results in a smaller pulse pressure
What happens to the PV loop in aortic stenosis?
It looks like a skyscraper. The afterload really increases, making the loop tall. EDV is slightly larger, ESV is much larger, and SV is much smaller.
Can the body overcome aortic stenosis?
Yes; the body will increase HR and systemic resistance to increase output. Frank-Starling mechanisms invoke to try to make an okay SV.
What causes angina with aortic stenosis?
The thickened wall means blood has farther to travel from epicardium to endocardium during diastole, which can create subendocardial ischemia and cause angina.
How can aortic stenosis cause sudden death?
Subendocardial ischemia can lead to lack of oxygen in the heart tissue and cause ventricular arrhythmia and death.
Describe the pathophysiology of aortic regurgitation.
LV volume overload leads to dilation and increased L pressure. The LA also dilates and there is increased optic use pressure.
What are the compensatory mechanisms for aortic regurgitation?
Eccentric LV hypertrophy, increased LV compliance, peripheral vasodilation.
What happens to aortic systolic and diastolic pressures in aortic regurgitation?
Systolic increases, diastolic decreases.
What does aortic regurgitation do to afterload?
Increase it.
Describe the PV loop in aortic regurgitation.
Another blob, but shifted right. LVEDV increases, SV increases (a lot is regurgitated) and peak pressure increases. The isovolumetric periods aren’t true ones.
