Valvular Heart Disease Flashcards
What percent of people have valvular disease in the US?
2.5%
What do you usually see with valvular heart disease?
Hemodynamic burden on the left or right ventricle
Pressure overload
Volume overload
Valvular heart disease coexists with what?
IHD
What two valvular diseases produce pressure overload?
Mitral stenosis
Aortic stenosis
What two valvular diseases produce volume overload?
Mitral regurg
Aortic regurgitation
50% of pts with aortic stenosis >50 years have what?
Ischemic heart disease
CAD pts with mitral or aortic valve disease ____ long term prognosis
Worsens
When assessing valvular disease, what are you looking for?
- Severity of cardiac disease
- Degree of impaired myocardial contractility
- Presence of associated major organ system disease
What are compensatory mechanisms in someone with valve disease?
- increased SNS
- myocardial hypertrophy
- current therapy
It’s important to evaluate and define ______ and _______ in valve disease pts
Exercise tolerance
Cardiac Reserve
Classification of pts with heart disease chart
Angina pectoris causes what?
Increased myocardial O2 demand
Ventricular hypertrophy
What symptoms will you get with impaired myocardial contractility?
Dyspnea/orthopnea
Easy fatiguability
Heart failure
- Basilar rales
- JVD
- 3rd heart sound
An increase in SNS (compensatory) will cause:
- Anxiety
- diaphoresis
- resting tachycardia
Causes of heart murmurs:
- Turbulent blood flow across abnormal valves
- Increased flow across normal valves
______ of the murmur in the cardiac cycle is the most important
Timing
(mid systolic vs holosystolic vs diastolic)
Distinguishing ________ murmurs from ________ murmurs due to structural heart disease is important because the presence of heart disease can change perioperative management and patient outcomes.
Functional
Pathologic
What are the characteristics we need to identify of a murmur?
Timing
Location
Radiation
Intensity
What is a functional murmur?
a heart murmur that is primarily due to physiologic conditions outside the heart, as opposed to structural defects in the heart itself.
midsystolic murmur can be ______ whereas any other murmur is very likely _______ and requires TTE
Functional
Pathologic
What happens during systole?
Aortic and pulmonic valves: open
Mitral and tricuspid valves: closed
What are characteristics of a systolic murmur?
- Stenosis of the aortic or pulmonic valves
- Incompetence of the mitral or tricuspid valves
What happens during diastole?
Aortic and pulmonic valves: closed
Mitral and tricuspid valves: open
What are characteristics of a diastolic murmur?
- Stenosis of the mitral or tricuspid valves
- Incompetence of the aortic or pulmonic valves
What are characteristics of a mid systolic murmur?
- Occur between distinct S1 and S2 heart sounds
- Crescendo–decrescendo pattern
- Can be functional
Where is a mid systolic murmur best heard?
Where does it radiate to?
- right upper sternal border
- radiates to the carotids suggests aortic stenosis
Where is a mid holosystolic murmur best heard?
Where does it radiate to?
- apex
- radiates to the axilla suggests mitral regurgitation
What does crescendo usually mean?
What about descresendo?
Gradually getting louder
Gradually getting softer
What 4 things usually occur between distinct first (S1) and second (S2) heart sounds and often have a crescendo–decrescendo pattern?
Midsystolic murmurs
Characteristic of functional murmur
Aortic stenosis
Hypertrophic cardiomyopathy
Characteristic of murmurs chart
Auscultation of murmurs picture:
Where is the aortic valve heard best?
2nd ICS RSB
Where is the pulmonic valve heard best?
2nd ICS LSB
Where is the tricuspid valve heard best?
5th ICS LSB
Where is the mitral valve heard best?
5th ICS MCL
________ may occur in patients with valvular heart disease, even in the absence of coronary artery disease
Why?
Angina pectoris
the demands of this thickened muscle mass may exceed the ability of even normal coronary arteries to deliver adequate amounts of oxygen
Types of diagnostics for valve disease
EKG
CXR
Echo
Angiography
What can an EKG diagnose?
(from valve disease lecture)
Left atrial enlargement
- broad, notched P waves
Left or right axis deviation
- left and right ventricular hypertrophy
Dysrhythmias
Possible ischemia/previous MI
What can CXR diagnose?
(from valve disease lecture)
Cardiomegaly
Left mainstem bronchus elevation
Valvular calcifications
On aposteroanterior chest radiograph,cardiomegaly can be established if the heart size exceeds _____% of the internal width of the thoracic cage
50
Enlargement of the left atrium can result in what?
elevation of the left mainstem bronchus
What can an echo diagnose or look at?
(from valve disease lecture)
- Cardiac anatomy and function
- Presence of hypertrophy
- Cavity dimensions
- Valve area
- Transvalvular pressure gradients
- Magnitude of valvular regurgitation
- Significance of murmurs
- Ventricular EF
- Evaluate prosthetic valve function
What can an angiography diagnose?
(from valve disease lecture)
- Presence and severity of valvular stenosis and/or regurgitation
- Coronary artery disease
- Intracardiac shunting
- Transvalvular pressure gradients
- Clinical vs echocardiographic findings
What are the two types of valves replacements and their differences?
Mechanical:
- Metal or carbon alloy
- Very durable… 20-30 years
- Highly thrombogenic
- Young pts
Bioprothetic
- Porcine or bovine
- Shorter lasting… 10-15 years
- Low thrombogenic potential
- Elderly pts
The temporary discontinuation of anticoagulant therapy puts patients with _______ heart valves or ______ at risk of arterial or venous thromboembolism.
Why?
Mechanical
A-fib
Due to a rebound hypercoagulable state and to the prothrombotic effects of surgery
When major surgery is planned, warfarin is typically discontinued _______ preoperatively.
3-5 days
What is administered after discontinuation of warfarin and continued until the day before or the day of surgery?
Intravenous (IV) unfractionated heparin or subcutaneous low-molecular-weight heparin (LMWH)
______ administration during the first trimester can be associated with fetal defects and fetal death
Warfarin
Mitral stenosis pt population characteristics
- Rare in the US
- Rheumatic heart disease
- Primarily affects women
- Asymptomatic for 20-30 years
Mitral stenosis pathophysiology
- Mechanical obstruction to LV filling d/t decrease in size of mitral valve orifice
- Diffuse thickening and fibrosis of mitral leaflet cusps, subvalvular apparatus, and commissural fusion
- Calcification of the annulus and leaflets
A normal mitral valve orifice area is ______. At what area do symptoms develop?
4-6 cm2
<2 cm2
What 3 things are maintained at rest by an increase in left atrial pressure?
mild mitral stenosis, left ventricular filling and stroke volume
What do commissures define?
a distinct area where the anterior and posterior leaflets come together at their insertion into the annulus
What does a sub-valvular apparatus consist of?
left ventricular free wall, two papillary muscles, and the chordae tendineae.
During ________, the sub-valvular apparatus prevents the mitral leaflets from prolapsing into the left atrium.
Ventricular systole
Leaflet thickening and calcification in mitral stenosis occur primarily due to:
the chronic stress of turbulent flow through a deformed valve
Mitral stenosis s/s
What are these associated with?
Dyspnea on exertion
Orthopnea
Paroxysmal nocturnal dyspnea
Pulmonary edema
Pulmonary HTN
Atrial fibrillation
The increase in LAP
When mitral stenosis is severe, any additional stress such as fever or sepsis may precipitate:
Pulmonary edema
Over time with mitral stenosis , changes in the pulmonary vasculature result in what?
Pulmonary hypertension
Eventually right sided heart failure
What might you see on CXR in mitral stenosis?
- Mitral calcification
- Pulmonary edema or vascular congestion
- Elevated left main bronchus
- Straightening of left heart border
What might you see on echo with mitral stenosis?
Calcification
Left atrial thrombus
Left atrial enlargement
What might you see on EKG with mitral stenosis?
Notched P waves
A-fob
What type of murmur in mitral stenosis?
Rumbling diastolic murmur at apex, radiates to left axilla
- Opening snap early in diastole
Mitral stenosis treatment
Rate control
- β-blockers, calcium channel blockers, digoxin
Left atrial pressure
- Diuretics
Anticoagulation - risk of stroke 7-15% per year
- Arterial thromboembolism vs venous thrombosis
Surgical correction
- Percutaneous valvotomy
- Surgical commissurotomy
- Valve replacement
What is the anesthetic goal in mitral stenosis?
Normal HR
Normal volume
Normal afterload
What are anesthetic considerations that could worsen pulmonary edema or decreased CO?
Excessive pre op IV fluid
Trendelenburg
How can you control fib RVR in mitral stenosis?
Cardioversion or IV administration of amiodarone
β-blockers
calcium channel blockers
What can you give to maintain SVR and BP with mitral stenosis?
Phenylephrine, vasopressin
What things could be diuretic induced complications with mitral stenosis?
Hypokalemia, orthostatic hypotension
What things could worsen pulmonary HTN in mitral stenosis during surgery?
Hypoventilation, hypercarbia, hypoxemia
In mitral stenosis, what are considerations for neuraxial anesthesia?
Maintain BP, preload, HR
What 2 induction drugs should be avoided in mitral stenosis?
Ketamine
- should be avoided because of its propensity to increase the heart rate
histamine releasing NMBs (pancuronium, atracurium)
- tachycardia or hypotension
T/F
Mitral regurgitation is more common than mitral stenosis
What % of the population has MR?
True!
2%
Mitral regurgitation is commonly associated with:
IHD
Ruptured papillary muscle
Endocarditis
Mitral valve prolapse
Cardiomyopathy
Why is acute mitral regurgitation often a sequelae of CAD?
myocardial ischemia and infarction cause papillary muscle dysfunction and, in some cases, papillary muscle rupture
Mitral regurg patho:
Decrease in forward LV SV and CO
Left atrial volume overload and pulmonary congestion
- Transforms LV
- Eccentric hypertrophy
- Compliance of left atrium
Regurgitant volume
- Size of the mitral valve orifice
- Pressure gradient across the mitral valve
Mitral regurgitation s/s
History of IHD, endocarditis, papillary muscle dysfunction
Holosystolic murmur at apex
- Radiates to axilla
Cardiomegaly
Atrial fibrillation
What might you see on EKG with mitral regurgitation?
Left atrial and LV hypertrophy
Atrial fibrillation
What might you see on CXR with mitral regurgitation?
Cardiomegaly
Left atrial and LV hypertrophy
What might you see on echo with mitral regurgitation?
Left atrial thrombus
Mitral regurgitation treatment
Transcatheter mitral valve repair
- MitraClip
Vasodilators, biventricular pacing
- ACE-I, β-blockers (carvedilol)
- MV repair > MV replacement
Why might early surgery be warranted in mitral regurgitation?
To prevent left ventricular dysfunction from. becoming severe or irreversible
T/F
In pts with mitral regurgitation, symptomatic pts can wait to have surgery if the EF is normal
False
They should undergo surgery, even if the EF is normal!
In asymptomatic patients with primary MR, surgical intervention is warranted in those with an LV ejection fraction of ____% to ____% or an LV end-systolic dimension greater than ____ mm.
30%-60%
40 mm
In symptomatic patients with severe primary MR, surgical intervention is undertaken if the LV ejection fraction is greater than _____% and LV end-systolic dimension is less than ____ mm.
30%
55 mm
Why is MV repair preferred to replacement?
it restores valve competence and maintains the functional aspects of the mitral valve apparatus
Anesthetic goal in mitral regurgitation
Prevention of what is important?
Improve forward LV SV and decrease regurgitant fraction
Decreased CO
In most pts with MR, CO can be maintained or improved with what?
Increase in HR
Decrease in SVR
- give vasodilators (nitroprusside)
Maintenance of ___________ is very important for maintaining left ventricular volume and cardiac output in mitral regurgitation
Intravascular fluid volume
Aortic stenosis is commonly associated with what?
Calcific aortic stenosis
Bicuspid aortic valve
Aortic stenosis develops earlier in life with ______ than with a ________
Bicuspid aortic valve
Tricuspid aortic valve
Aortic stenosis affects as many as ____% of all adults older than age _____
25%
65 years
What percent of the population have a BAV?
1%-2%
What age does aortic stenosis develop with BAV vs the age it develops with tricuspid?
Age 30-50
Age 60-80
What else is BAV associated with?
dilatation of the aortic root and/or ascending aorta that occurs at a younger age compared to that seen with a stenotic tricuspid aortic valve
Aortic stenosis patho
Obstruction to ejection of blood into the aorta
Increased LV pressure
Normal valve area 2.5 - 3.5 cm2
- Severe AS valve area < 1cm2
Always associated with AR
Concentric LV hypertrophy
- increase in myocardial oxygen requirements
What is concentric hypertrophy?
thickening of LV d/t chronic pressure overload, susceptibility to ischemia d/t oxygen supply–demand imbalance
Aortic stenosis s/s
Systolic or midsystolic murmur: right upper sternal border
- Crescendo–decrescendo pattern
- Radiates to neck, mimics carotid bruit
Critical AS
Angina pectoris
- Increased risk of peri-op mortality and MI
Syncope
Dyspnea on exertion
Aortic stenosis symptoms correlate with an average time to death of ___, ____, and ____ years without AVR
5, 3, 2
What percent of symptomatic aortic stenosis pts die within 3 years without a valve replacement?
75%
Dyspnea in aortic stenosis typically occurs as a result of:
diastolic dysfunction, caused by elevated LV filling pressures in the noncompliant, hypertrophied left ventricle
What would you expect to see on CXR in aortic stenosis?
Prominent ascending aorta d/t post-stenotic aortic dilation
Aortic valve calcification
What would you expect to see on EKG on pts with aortic stenosis?
LV hypertrophy
ST Depression
T wave inversion
What would you expect to see on echo on pts with aortic stenosis?
- Tri-leaflet vs bi-leaflet valve
- Thickened and calcified
- Valve area and transvalvular pressure gradients
- LV hypertrophy
- LV systolic or diastolic dysfunction
What would you expect to see on exercise stress testing on pts with aortic stenosis?
Poor exercise tolerance &/or abnormal BP with exercise
In the asymptotic elderly population with severe aortic stenosis, elevated levels of what may suggest early clinical decompensation?
BNP
In symptomatic patients with adecreased ejection fraction, elevated _____ has been associated with decreased ____ year survival after AVR
BNP
1 year
Asymptomatic aortic stenosis has a ____ onset and ____ of symptoms. Often leads to _____
Rapid
Progression
Sudden death
Aortic stenosis treatment
- Balloon valvotomy for adolescents/young adults
- Transcatheter aortic valve replacement(TAVR)
What is often done at the same time as AVR in patients with both aortic stenosis and significant coronary artery disease?
Coronary revascularization
There is regression of _____ and ____ increases with AVR
left ventricular hypertrophy
EF
Percutaneous aortic balloon valvotomy can be beneficial in adolescents and young adults with:
congenital or rheumatic aortic stenosis
Certain factors that must be considered for a high risk TAVR pt:
- age is over 65 years,
- transfemoral TAVR is feasible
- aortic valve is trileaflet
- absence of high-risk anatomic features such as adverse aortic root, low coronary ostia height, or LV outflow tract calcification
Aortic stenosis anesthetic considerations
Prevention/avoidance of hypotension and decreased CO
Maintain NSR
- Avoid bradycardia or tachycardia
Optimize intravascular fluid volume
Aggressive treatment of hypotension
CPR is typically not effective
In aortic stenosis, a decrease in HR can cause:
Overdistention of the LV
In aortic stenosis, HR determines what 3 things?
determines the time available for ventricular filling, ejection of the stroke volume, and coronary perfusion
Why is CPR typically ineffective in aortic stenosis pts?
it is essentially impossible to create an adequate stroke volume across a stenotic aortic valve with cardiac compressions done either externally or internally.
During induction of aortic stenosis pts, what are some important considerations?
GA > epidural or spinal
Avoid decreased SVR
What meds should you avoid for induction with aortic stenosis pts?
Opioids that cause histamine release (morphine, hydromorphone)
Ketamine
Pancuronium/atracurium
What can you give for hypotension in aortic stenosis pts?
Alpha agonists (neo)
What should you avoid for a junctional rhythm or bradycardia in aortic stenosis?
Ephedrine, atropine, glycopyrrolate
What should you give for tachycardia in aortic stenosis?
Beta blockers (esmolol)
What is aortic regurg?
What are the causes?
Failure of aortic leaflets caused by disease of the aortic leaflets or aortic root
- Endocarditis
- Rheumatic fever
- Bicuspid aortic valve (BAV)
- Anorexigenic drugs
- Aortic dissection (acute)
What are anorexigenic drugs?
substances that tend to suppress appetite orhunger sensationor both
phentermine, methamphetamine
Aortic regurgitation pathophysiology
Decreased CO d/t regurgitant SV
Combined LV pressure and volume overload
Usually slow onset
Magnitude of regurgitation depends on:
- Time available for regurgitant flow (HR)
- Pressure gradient across the aortic valve (SVR)
When does aortic regurgitation occur?
Diastole
In aortic regard, what is the volume overload a consequence of?
the regurgitant volume itself and is therefore directly related to the severity of the leak.
In aortic regurg, pulse pressure in proportional to what?
Increased stroke volume increases what?
Systolic HTN increases what?
Stroke volume
Aortic elastance
SBP
Afterload
What type of hypertrophy is seen in aortic regurgitation?
Why?
Eccentric
it’s enlarging to accommodate volume overload
Aortic regurg symptoms
Early or mid-diastolic murmur, at the left sternal border
- Low-pitched diastolic rumble (Austin-Flint murmur)
Hyperdynamic circulation
- Widened pulse pressure
- Decreased DBP
- Bounding pulses
LV failure (end stage)
- Dyspnea, orthopnea, fatigue and coronary ischemia
Acute AR – severe LV volume overload
- Coronary ischemia, rapid deterioration LV function, and HF
What might you see on EKG/CXR in a pt with arortic regurg?
LV enlargement and hypertrophy
What might you see on echo in a pt with aortic regurg?
- Leaflet prolapse or perforation
- Associated aortic abnormalities
Medical and surgical treatment for aortic regurg
Medical
- Decrease systolic HTN, LV wall stress, and improve LV function
- Diuretics, ACE-I, CCB
Surgical
- AVR
- Aortic root replacement
Why is immediate surgical intervention necessary in acute aortic regurg?
the acute volume overload results in heart failure
Anesthetic goal in pts with aortic regurg
Maintain forward LV SV
Avoid bradycardia
- HR: > 80 bpm
Avoid increased SVR
Minimize myocardial depression
- Vasodilator to reduce afterload
- Inotrope to increase contractility
Why must the HR be maintained >80 in aortic regurg?
In bradycardia, by increasing the duration of diastole and thereby the time for aortic regurgitation, produces acute left ventricular volume overload
Anesthetic considerations of aortic regurg
GA is usual choice
Induction
- Inhaled anesthetic or IV drugs
- Avoid decreased HR or increased SVR
- NMBDs w/ minimal or no effect on BP
Intravascular fluid volume - normal levels to provide adequate preload
What valve disease do we worry about the most?
Aortic stenosis
