Valvular Heart Disease

How can you assess cardiac reserve?
Exercise tolerance

Mitral stenosis, what is it?
fusion of the mitral valve leaflets from healing from acute rheumatic fever. Mitral valve area is <1cm2 (normal 4-6cm2), a mean LAP around 25mmHg to compensate! Left atrial enlargement predisposes to A Fib (clotting issues)

Symptoms of Mitral Stenosis
DOE when CO is increased
leads to CHF

Goals of management of anesthesia with Mitral Stenosis
avoid sinus tach or rapid ventric response rate during a fib (will lead to htn)
no increases in central blood volume
no drug-induced decreases in SVR
avoid hypoxemia and/or hypoventilation that may exacerbate pulm HTN and cause RVF

Induction considerations with Mitral stenosis?
use drugs that won’t increase HR (avoid Ketamine) or abruptly decrease SVR (avoid pure propofol)

Maintenance phase considerations with mitral stenosis?
minimize marked and sustained changeds in HR, SVR, PVR, and myocardial contractility. Use monitors as warranted.

Mitral regurgitation, what is it?
usually d/t rheumatic fever and almost always a/w mitral stenosis. LA volume overload by retrograde flow of a portion of the LVSV into the LA

Where can you see the regurgitant flow?
V wave present on the recording of the PAOP

Anesthesia mgt goals of mitral regurgitation?
avoid sudden decreases in HR
avoid sudden increases in SVR
Monitor V-wave size as reflection of regurgitant flow
Minimize drug-induced myocardial depression

Induction considerations with mitral regurgitation?
avoid excessive and abrupt changes in SVR or decreases in HR

Maintenance of anesthesia with mitral regurgitation?
Influenced by degree of LV dysfunction
-Absence of severe LV dysfunction: maintenance often with nitrous oxide plus a volatile anesthetic
-Severe LV dysfunction: opioid technique to minimize the likelihood of drug-induced myocardial depression

Aortic stenosis, what is it?
If alone, usually r/t abnormal bicuspid valve, but if from rheumatic fever almost always occurs in association w/ MVS

Hemodynamically significat aortic stenosis is normally a/w:
transvalvular pressure gradient > 50mm Hg
aortic valve orifice area <1cm2 (normal 2.5-3.5cm2)

Triad of symptoms with aortic stenosis
angina pectoris (often in absence of ischemic heart disease)
dyspnea on exertion
history of syncope

Goals of management of anesthesia of aortic stenosis
Avoid events that would further decrease cardiac output!
-maintain NSR and avoid bradycardia!
-avoid sudden increases or decreases in SVR (do NOT do regional anesthesia r/t sympathectomy)
-optimize intravascular fluid volume to maintain venous return and LV filling

WTF is aortic regurgitation?
Several things can cause it, but the problem is a decrease in forward LVSV d/t regurgitation of part of the SV from the aorta back into the LV

Management of anesthesia goals with aortic regurgitation?
maintain forward left ventricular stroke volume
-avoid sudden decreases in HR
-avoid sudden increases in SVR
-minimize drug-induced myocardial depression (consider balanced technique over high gas technique as opioids do NOT depress contractility!)

Induction and maintenance considerations with aortic regurgitation
Induction with drugs that will maintain forward left ventricular stroke volume
maintenance depends on degree of LV dysfunction
Little LV dysfunction:nitrous oxide plus volatile agent
Severe LV dysfunction: high opioid anesthetic

Overall, what are some maintenance of anesthesia considerations for the valvular heart diseases?
Maintenance of IV fluid folume with prompt replacement of blood loss–maintain forward LVSV
Avoid bradycardia and treat it promptly with atropine
Monitor based on complexity of surgery

Leave a Reply

Your email address will not be published. Required fields are marked *