Aortic Stenosis Flashcards
What is range velocity for mild to critical stenosis for AS?
mild < 3 m/sec
moderate 3–4
severe 4 - 4.5
critical > 4.5
What is range aortic valve area for normal to critical stenosis for AS?
normal 2.5 - 4.0 cm2 mild 1.5 - 2.0 moderate 1.0 - 1.5 severe 0.7 - 1.0 critical < 0.7
What is range mild transvascular gradient for mild to critical stenosis for AS?
mild < 25 mmHg
moderate 25 - 40
severe 40 - 50
critical > 50
What patient’s require bacterial endocarditis PPX?
1) prosthetic cardiac valve or prosthetic material used for valve repair
2) prior infectious endocarditis
3) unrepaired cyanotic congenital heart disease
4) 6mo post-op period following a repaired congenital heart defect using prosthetic material or a device
5) repaired congenital heart disease with residual defects at the site or adjacent to the site of a prosthetic patch or device
6) cardiac transplant recipients who develop cardiac valvopathy
Heparin 5000SQH: time to hold before epidural, when to restart after epidural
wait 4-6hrs for placement
can restart immediately, takes 2hrs for drug effect
Heparin gtt: time to hold before epidural, when to restart after epidural
wait 2-4hrs after stopping
delay starting for 1hr after placement
LMWH: time to hold before epidural, when to restart after epidural
low dose lovenox 40mg
delay for 12hrs following low dose
high dose lovenox 1mg/kg BID
delay 24hrs for high dose
Abciximab: time to hold before epidural, when to restart after epidural
delay for 1-2 days
Apixaban: time to hold before epidural, when to restart after epidural
delay for 72hrs (longer with renal impairment)
wait to restart until 6hrs after
How much does atrial kick contribute to cardiac output in normal patient? Pt with aortic stensois?
normal 20%
AS 30 - 40% due to decreased compliance of the left ventricle
What causes concentric ventricular hypertrophy?
results from pressure overload
sarcomeres are added in paralleled (thickening rather than lengthening)
ventricular volume is not increased
What causes eccentric ventricular hypertrophy?
results from volume overload
sarcomeres are added in series (lengthening rather than thickening)
ventricular volume is increased
how long do you postpone elective surgery for angioplasty, BMS, DES?
angioplasty - 14 days
BMS - 1 month
DES - 6 months (can do 3mo if risk of delaying surgery more than risk of stent thrombosis). Continue plavix for 1 year after.