Valvular Heart Disease Flashcards
1
Q
Aortic Stenosis
A
essentials of DX:
- congenital bicuspid aortic valve (usually asx until middle or old age)
- “degenerative” or calcific aortic stenosis; same risk factors as atherosclerosis
- sxs likely once the mean gradient is >40 mmHg
- delayed and diminished carotid pulses
- soft, absent, or paradoxically split S2
- harsh systolic murmur, sometimes w/ thrill along LSB, often radiating to neck; may be louder at apex in older pts
- ECG usually shows LVH; calcified valve on radiography or fluoroscopy
- Echo/Doppler is diagnostic
- sx indicated for sxs; low surgical risk; percutaneous valve replacement may be option for high risk surgical placement
- sx considered for asx pts w/ severe aortic stenosis
- emerging role of BNP as marker of early LV myocardial failure
2 clinical scenarios for aortic stenosis:
- congenitally abnormal unicuspid or bicuspid valve instead of tricuspid
- sxs in young or adolescent if stenosis is severe but more often emerge at 50-65 yo when calcification and degeneration of valve manifest
- dilated descending aorta (50% of pts) and sometimes coarctation of aorta
- offspring of pts w/ bicsupid valve have much higher incidence of disease
- degenerative or calcific aortic stenosis
- related to Ca deposition due to processes similar to in atherosclerosis
***aortic stenosis produces progressive afterload increase to LV; to reduce wall stress, ventril hypertrophies and increases wall thickness (concentric hypertrophy)l sometimes severe LVH ensues***
S:
- LV failure, angina pectoris, or syncope my be presenting sxs and signs of significant aortic stenosis
- importantly all sxs tend to occur with exertion!
O:
- slightly narrowed, thickened, or roughened valves (aortic sclerosis) or aortic dilation may produce typical ejetion mumur of aortic stenosis
- characteristic systolic ejection murmur is heard at the aortic area and usually transmitted to neck and apex
- in mild or moderate cases where valve is still pliable, ejection click may precede murmur
- severe cases = palpable LV thrill or heave, weak to absent aortic second sound or reveresed splitting of the second sound if present
- when valve is very narrow, ventricular systole is prolonged and carotid pulse of delayed upstroke and low amplitude
