Cardiac Abnormalities Flashcards
Stenotic
Doesn’t open fully
- Chamber upstream has to develop more systolic pressure in order to achieve a given flow thru valve
- Inc. “pressure” work (after load) –> hypertrophy
Insufficient
Doesn’t close completely
- Regurgitant blood flow represents an additional volume that must be ejected to get sufficient forward flow
- Inc. “volume” work (stroke volume) -> chamber dilation
What is aortic stenosis?
Aortic valve doesn’t open fully
-Inc. resistance to flow
What are the signs of aortic stenosis?
- Significant pressure difference between LV and Aorta.
- Intraventricular pressure rises VERY HIGH during systole [150 mmHg] (KNOW)
- Aortic pressure is subnormal in systole
- Low pulse pressure
- High ejection velocity of blood leads to systolic murmur
What does aortic stenosis cause?
- Cardiac muscle hypertrophy and increase left ventricular muscle mass
- Left axis deviation
- Very high ventricular after load!!
What is mitral stenosis?
- Mitral valve doesn’t open fully
- Increased resistance to flow
What are the signs of mitral stenosis?
- Left atrial pressure raised up around 40-45 mm Hg
- Pressure difference for more than a few mmHg across the mitral valve during diastole
- Elevated left atrial pressure
- Turbulent flow of blood leads to diastolic murmur
What can mitral stenosis do to the heart?
Induce hypertrophy of left atrial muscle
What is the physiological consequence of mitral stenosis?
- High left atrial and pulmonary capillary pressures
- High pulmonary capillary pressures (increased hydrostatic pressure) can cause pulmonary edema and interfere with gas exchange in lungs (symptoms: SOB/dyspnea)
What is aortic insufficiency?
Leaflets of aortic valve do not seal –> blood regurgitates back into LV during diastole
What are the characteristic signs of aortic insufficiency?
- Aortic pressure falls faster/farther than normal diastole
- Low diastolic pressure
- Large pulse pressure
- Ventricular EDV and EDP are higher than normal bc extra blood reenters the chamber
- Turbulent flow of blood reentering LV causes a diastolic murmur
What is the physiological consequence of aortic insuffiency?
-Reduced ejection fraction, increased volume workload
Often aortic valve is BOTH stenotic and insufficient & BOTH. . .
systolic & diastolic murmurs will be heard
What is mitral regurgitation (insufficiency)?
Leaflets of mitral valve do not seal -> blood regurgitates back into left atrium during systole
What are the characteristic signs of mitral regurgitation (insufficiency)?
- Left atrial pressure is abnormally high [50 mmHg]
- Left ventricular EDV and EDP increase
- Systolic murmur