Aortic valve Stenosis Flashcards
1
Q
Aortic valve anatomy:
A
- made of 3 leaflets: left, right, posterior
- opens during systole
- closes during diastole
2
Q
Aortic stenosis: def
A
- aortic valve doesn’t open all the way, gets harder to pump out to the body
3
Q
Aortic stenosis: causes
A
- mechanical stress over time, causing fibrosis and calcification, occurs with patients over 60 years old
- bicuspid aortic valve, only has 2 leaflets, are at greater risk of developing fibrosis and calcification as the mechanical stress is not well distributed
- chronic rheumatic fever -> can cause repeated inflammation and repair -> fibrosis -> can cause commissural fusion (an important distinction from the type caused by mechanical stress over time)
4
Q
Aortic stenosis: consequences
A
- since it’s harder to open and push blood past the hardened valve -> left ventricle generates higher pressures each time it contracts to get the same amount of blood through -> left ventricle thickens: concentric left ventricular hypertrophy -> struggles to deliver blood to the organs -> risk of developing heart failure
5
Q
Aortic stenosis: symptoms
A
- syncope
- chest pain and angina due to thickening
- exertional dyspnea
Patients might not initially experience symptoms at rest, only during exercise, because of the higher blood requirement - microangiopathic hemolytic anemia: damage to red blood cells as they’re forced through the smaller valve -> splitting them into smaller fragments called schistocytes -> leading to hemoglobinuria (hemoglobin in the urine)
6
Q
Aortic stenosis: D
A
- auscultation: crescendo-decrescendo murmur, mid-systolic murmur
- ECG: BBB, LVH
- CXR
- TTE: Transthoracic Echocardiogram
7
Q
Aortic stenosis: severity and prognosis
A
- classified according to pressure gradient and valve area, poor if no surgery
8
Q
Aortic stenosis: treatment
A
- aortic valve replacement
- contraindications: nitrates, ACEi
