Cardiac II: Valvular Heart Disease

Question 1

What do you want HR and rhythm to be with AS?

Answer 1

70-80 bpm and NSR

Question 2

What will tachycardia cause with AS?

Answer 2

tachycardia leads to decreased time for ventricular filling which causes decreased LVEDV that then causes decreased SV and decreased CO

Question 3

What is the problem with bradycardia and AS?

Answer 3

bradycardia causes a decrease in CO which will cause LV over distension which compresses the sub endocardium which causes myocardial oxygen supply to decrease

Question 4

In a patient with AS what will you want your preload to be and why?

Answer 4

Increased

You need adequate LVEDP (volume) to fill the non-compliant LV

Question 5

What happens to the LV in aortic stenosis?

Answer 5

aortic stenosis is increased pressure needs to overcome the stenotic valve, thus the L ventricle wall becomes thicker , this is known as concentric hypertrophy

Question 6

How can you ensure adequate intravascular volume with AS?

Answer 6

Administer IVF

Question 7

Formula for BP?

Answer 7

SVR X CO

Question 8

SVR that you want with a patient who has AS?

Answer 8

Maintain or increase

Question 9

Tell me about stroke volume and CO in the AS patient?

Answer 9

stroke volume is fixed by the stenotic aortic valve, therefore CO is dependent on HR

(BP = SVR X CO)

Question 10

Do you want hypotension with AS?

Answer 10

NO!

Hypotension decreases aortic root pressure which decreases CPP which leads to myocardia ischemia

Question 11

How should you treat hypotension in the AS patient?

Answer 11

treat with an alpha 1 agent, this will increase SVR and CPP without increasing HR

Question 12

CPR in the patient with AS….??

Answer 12

Chest compressions during CPR won’t generate sufficient intracardiac pressure to overcome the stenotic aortic valve.

Question 13

Where is afterload set in the AS patient?

Answer 13

at the aortic valve (which is stenotic)

Question 14

Regional anesthesia and AS?

Answer 14

Spinal is avoided in severe AS (<0.8) because it rapidly reduces SVR which leads to profound hypotension (BP = SVR X CO).

A reduction in SVR reduces CPP which leads to cardiovascular collapse

Question 15

Can you do epidural anesthesia in a patient with AS?

Answer 15

If the patient does not have severe AS epidural can be done on a individual basis.
Slow onset LA should be used and a lower block height tends to cause a less dramatic drop in hemodynamics.

Question 16

What does the AS patients arterial waveform look like?

Answer 16

typically no dicrotic notch

slower systolic upstroke (pulsus tardus)

small amplitude with narrow pulse pressure due to reduced SV (pulsus parvus)

dampened waveform overall

Question 17

Most common cause of Aortic Stenosis?

Answer 17

Bicuspid aortic valve and calcification

Question 18

Tell me your goals /concerns with the aortic stenosis patient?

Answer 18

You are concerned with rate, volume, and afterload.

Maintain NSR
Increase Preload
Afterload is kept high

WHY?
Tachycardia reduces filling time. Bradycardia creates LV distension

Volume: increase preload, keep CVP and PAOP high /normal

Afterload is set by the stenotic aortic valve. SVR must be kept high to help perfuse the coronary arteries (CPP = AoDBP - LVEDP)

Question 19

Stenosis requires full, fast, and forward or slow, full, and tight?

Answer 19

Stenosis = Slow, full, and tight

Question 20

Regurgitation requires full, fast, and forward or slow, full, and tight?

Answer 20

Regurgitation = Fast, Full, forward

Question 21

What dysrhythmia is common with mitral valve disease associated with left atrial enlargement?

Answer 21

A - fib

Question 22

Which cardiac lesions require a slow heart rate to prolong the duration of diastole and improve left ventricular filling and coronary blood flow?

Answer 22

aortic and mitral stenosis

Question 23

Which valvular lesions require a faster heart rate and afterload reduction?

Answer 23

aortic and mitral regurgitation

Question 24

Which induction drug do you want to avoid and why if a patient has mitral stenosis?

Answer 24

Ketamine because it typically increases the HR