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Heart Murmurs & Valvular Heart Disease
Victor Politi, M.D., FACPMedical Director, SVCMC, School of Allied Health Professions, Physician Assistant Program
What is a Heart Murmur?
A sound produced as blood flows through the chambers and large blood vessels of the heart during the cardiac cycle of contraction and relaxation.
The heart beat normally makes two sounds: the first is Lub and the second is Dub,
these two sounds follow each other (Lub Dub) and are not separated by any extra sounds.
What is a Heart Murmur?
A heart murmur will be heard as a swishing or a whistling sound in addition to the normal Lub-Dub sound.
The moving blood sounds like running water in a garden hose.
What is a Heart Murmur?
A heart murmur is not a diagnosis or disease, it is a sign to alert our attention to check if there is anything wrong.
Heart murmurs come in different sounds which may help indicate whether the murmur is normal or abnormal.
What is a Heart Murmur?
Some murmurs are benign or harmless and are more of a finding than a condition.
A benign murmur is not associated with any significant underlying abnormality of the heart or its vessels.
What is a Heart Murmur?
Many young people can have benign/innocent flow murmurs and still have normal cardiac structure and function.
What is a Heart Murmur?
What causes a heart murmur?
Innocent/Benign Murmur Causes: Anemia Fever Venous Hum
a common innocent murmur heard during childhood. This murmur is heard as a soft humming sound at the base of the neck just above the collarbone. It results from the normal blood flow in the large neck veins (jugular veins).
Innocent/benign Causes: Venous Hum
Light compression of the neck vein will make the murmur transiently disappear, or the murmur will sound louder when turning the child's head to one side or another.
These simple maneuvers help differentiate a Venous Hum from the murmurs resulting from heart disease.
Innocent/benign Causes: Still’s Murmur
This heart murmur is named after the doctor who described it.
It is heard most frequently in active, healthy 3 to 7-year old children.
The murmur represents the normal sound of blood gushing out into the aorta during heart contraction.
It has a musical tone to it and thus is frequently described as "musical murmur"; it usually sounds softer during sitting and may sound very loud during fever, anxiety, or exercise.
Still’s Murmur
Pathologic Murmur
A pathologic heart murmur is one associated with a structural or functional abnormality of the heart.
Pathologic Murmurs
Narrow Valve- stenosis Valve insufficiency/regurgitationSeptal defects- Hole in the Heart
Valve insufficiency/regurgitation
As the heart valve closes some blood leaks back making a blowing sound.
A leaking valve is called insufficient or regurgitating.
Its importance depends on how much blood is leaking, what valve is involved, and how long it has been going on.
Septal defects – hole in heart
If the pressure in the heart chambers is not the same, the blood will flow from the high to the low-pressure chamber, producing a murmur sounding like a waterfall.
If the hole is small, it will make a very loud sound.
If the hole is large it may make a faint murmur that may go unnoticed for some time; therefore a faint murmur may sometimes indicate a serious problem.
If it is between the upper cardiac chambers, it is called Atrial Septal Defect (ASD), and is called Ventricular Septal Defect (VSD) if it is between the lower cardiac chambers.
The importance of septal defects depends on their size and site.
Septal defects – hole in heart
Most murmurs are produced as blood flows past the cardiac valves, which separate the chambers of the heart, or through the valves that lead to the great vessels of the lungs and the systemic circulation.
Mechanisms of Heart Murmurs
Mechanisms of Heart Murmurs
They are usually caused by one of the following mechanisms: Flow across partial obstruction (e.g. aortic
stenosis) Flow across valvular or intravascular
irregularity w/o obstruction (e.g. bicuspid aortic valve w/o true stenosis)
Increased flow through normal structures (e.g. aortic systolic murmur associated w/anemia)
Flow into dilated chamber (e.g. aortic systolic murmur associated w/aneurysmal dilatation of the ascending aorta)
Backward or regurgitant flow across an incompetent valve or defect (e.g. mitral regurgitation)
Shunting of blood out of a high pressure chamber or artery through abnormal passage (e.g. ventricular septal defect)
Mechanisms of Heart Murmurs
Midsystolic Ejection Murmurs
Most common type of murmurMay be:
1. Organic (i.e. secondary to structural cardiovascular
abnormality)
2. Functional (i.e. secondary to a physiologic alteration w/or w/o
heart dx)
3. Innocent(i.e. not associated with any functional or structural
abnormality)
Organic causes include: Aortic stenosis Pulmonoic stenosis
Midsystolic Ejection Murmurs
Pansystolic Regurgitant Murmurs
Heard when blood flows from a chamber of high pressure to one of lower pressure through a valve or other structure that should be closed.
Regurgitation (incompetence or insufficiency) means there is a leak!
The murmur begins immediately with the 1st heart sound and continues up to the 2nd heart sound.
Causes include: Mitral regurgitation LV LA Tricuspid regurgitation RV RA Ventricular septal defect LV RV
Pansystolic Regurgitant Murmurs
Diastolic Murmurs
Unlike systolic murmurs, diastolic murmurs are almost always indicative of heart disease.
Two general types may be distinguished:
The diastolic rumble originating in atrioventricular valves
The early diastolic murmurs of semilunar valve incompetence
Diastolic rumbling murmurs are caused by: Flow across distorted or stenotic mitral
or tricuspid valves Increased blood flow across normal
mitral or tricuspid valves
Diastolic Murmurs
Because these valves open only after the aortic and pulmonic valves close, a short period of silence separates S2 from the beginning of diastolic rumbles.
These murmurs are low in pitch, rumbling in quality, and heard best with the bell of the stethoscope in light skin contact.
Diastolic Murmurs
Semilunar valve incompetence may result either from valvular deformity or from dilatation of the valvular ring.
In either case blood regurgitates from the great vessel back into the ventricle.
Diastolic Murmurs
Murmurs of aortic regurgitation, together with most murmurs of pulmonic regurgitation, start immediately after the second sound and then diminish in intensity
In contrast to the rumbling atrioventricular valve murmurs, they are high pitched and blowing and best heard with the diaphragm pressed firmly on the chest.
Diastolic Murmurs
The most common examples of these two types of diastolic murmurs are:
Mitral stenosis Aortic regurgitation
Diastolic Murmurs
Points to Remember !
If the flow is excessive or turbulent, a murmur may be manifest.
Blood flowing through a tight valve will produce a murmur.
Blood that is leaking back across an improperly sealing valve also can cause a murmur.
Occasionally, abnormal communications (holes) between chambers of the heart can result in the presence of a murmur.
Diagnosing a Murmur
Diagnosing a heart murmur begins with auscultation of the heart.
The location, quality, pitch and variation in the sound are all important clues to whether the murmur is benign or pathologic.
Murmur Evaluation
One of the most useful tests in evaluating a murmur is an echocardiogram.
Other tests – EKG Chest x-ray
Valvular Heart Disease
90% of valvular disease is chronic, with decades between the onset of the structural abnormality and symptoms
The four heart valves prevent retrograde flow of blood during the cardiac cycle, allowing efficient ejection of blood with each contraction of the cardiac chambers
The mitral valve has two cusps, while the other three heart valves normally have three cusps
The right and left papillary muscles promote effective closure of the tricuspid and mitral valves, respectively.
Valvular Heart Disease
Mitral StenosisMitral RegurgitationAortic StenosisAortic RegurgitationTricuspid StenosisTricuspid Regurgitation
Mitral Stenosis
Mitral Stenosis- Pathophysiology
Despite its declining frequency, rheumatic heart disease is still the most common cause of mitral valve stenosis
Due to progressive dilation of the atria, many patients with mitral stenosis will go on to develop atrial fibrillation
Mitral Stenosis
Normal mitral valve 4-6cm2
When the valve narrows <1.5cm2, left atrial pressure must rise to maintain normal flow across the valve and a normal cardiac output
This results in a pressure difference between the left atrium and the left ventricle during diastole
Mitral Stenosis
In mild cases of mitral stenosis, the patient may be asymptomatic and cardiac output and left atrial pressure may be normal
In moderate cases (valve area < 1.5cm2) as left atrial pressure rises - dyspnea and fatigue appear
Mitral Stenosis
With severe stenosis, pulmonary venous congestion at rest and reduced cardiac output occur resulting in dyspnea, fatigue, and right sided heart failure
Mitral Stenosis - Clinical Findings
Dyspnea In 80% of cases, most common presenting
symptom Paroxysmal nocturnal dyspnea
hemoptysis 2nd most common symptom
OrthopneaSymptoms often precipitated by onset of
pregnancy or atrial fibrillation
Mitral Stenosis - Clinical Findings
Murmur duration varies - severity of stenosis &
heart rate middiastolic rumble, crescendos into S2
Heart Sounds long snapping S1
apical impulse is small and tapping due to underfilled left ventricle
Mitral Stenosis - Murmur
The pressure gradient and the length of the diastolic murmur reflect the severity of mitral stenosis
Mitral StenosisDiagnostic Studies
Echocardiography reveals thickened valve that opens poorly, closes
slowly rather than moving in opposite directions, the
anterior and posterior leaflets are fixed, moving together
rule out atrial myxoma (clinical presentation similar to mitral stenosis)
left atrial size can be accurately measuredincreased size - increased risk of atrial fibrillation or
systemic emboli
Mitral Stenosis - Diagnostic Studies
ECG may show notched or diphasic P waves and
right axis deviationX-ray
early finding- straightening of left heart border (left atrial enlargement)
subsequent findings - pulmonary congestion, redistribution of flow to upper lung fields, Kerley B lines, along with an increase in vascular markings
Kerley B lines are short, horizontal linear radiopacities at the periphery of the lung that represent thickened, interlobular septa
Mitral Stenosis -Treatment
Warfarin anticoagulation - after A-Fib Surgery - indications
uncontrolled pulmonary edema limiting dyspnea & intermittent pulmonary
edema pulmonary HTN w/right ventricular
hypertrophy or hemoptysis limitation of activity despite ventricular rate
control/medical therapy recurrent systemic embolic despite
anticoagulation w/moderate-severe stenosis
Mitral StenosisTreatment
Open mitral commissurotomy patients w/o substantial mitral
regurgitationValve replacement surgery
indicated when combined stenosis and insufficiency are present or when the mitral valve is so distorted and calcified that a satisfactory valvulotomy is impossible
Mitral Stenosis
Prosthetic valves Warfarin anticoagulant therapy required -
usually for at least initial 3 months with bioprosthesis - if atrial fibrillation persists - anticoagulation therapy should continue
possible problemsthrombosisparavalvular leakendocarditisdegenerative changes in tissue valves
Mitral StenosisTreatment
Balloon valvuloplasty effective in patients w/o mitral
regurgitation and in cases where valve calcification is not excessive
Mitral Regurgitation(Mitral Insufficiency)
(Mitral Incompetence)
Mitral Regurgitation
The mitral leaflets do not close normally during left ventricular systole, blood is ejected into the left atrium as well as through the aortic valve
this results in increased volume load on the left atria
Mitral Regurgitation
Mitral Regurgitation leads to left atrial enlargement - subsequently resulting in atrial fibrillation
Mitral Regurgitation
Case presentation varies depending upon the speed with which the condition develops
In acute cases, left atrial pressure elevates abruptly can result in pulmonary edema if severe
Mitral Regurgitation
Acute cases Typically, patient presents with dyspnea,
tachycardia, and pulmonary edema ECG-may show evidence of acute inferior wall
infarction (more common than anterior wall) absent to minor calcification of mitral valve no stenosis, little left ventricle dilation X-ray-minimally enlarged left atrium,
pulmonary edema - from papillary muscle rupture
Mitral Regurgitation
In chronic cases, the left atrium dilates, left atrial pressure rises little, even with large regurgitant flow slowly progressive- years to decades exertional dyspnea (1st symptom), and fatigue that
progress gradually over years pressure in the pulmonary veins show a transient rise
during exercise ECG-may demonstrate LVH x-ray-left ventricular/atrial enlargement in proportion to
severity of regurgitant volume
Mitral Regurgitation
Intermittent cases typically present with acute episodes of
respiratory distress due to pulmonary edema
can be asymptomatic between attacks
Mitral Regurgitation
Many causes - rheumatic disease myxomatous degeneration (mitral valve
prolapse) connective tissue disease (Marfan's
syndrome) infective endocarditis cardiac tumors (myxoma) - rare cause
Mitral Regurgitation
Nonrheumatic mitral regurgitation may develop suddenly after MI,valve perforation in infective endocarditis, or ruptured chordae tendineae in MVP
Inferior MI due to right coronary occlusion is the most common cause of ischemic mitral valve incompetence
Mitral Regurgitation
Rheumatic heart disease is the most common cause of chronic mitral incompetence
Mitral Regurgitation
Appetite suppressant drugs (fenfluramine and phentermine, or dexfenfluramine) have been associated with cardiac valve incompetence
Mitral Regurgitation
Murmur Acute; harsh apical systolic murmur,
begins with S1, may end before S2
Heart Sounds S1 and S2 are heard
Mitral Regurgitation - Diagnostic Studies
Echocardiography
TEE
Nuclear Medicine/MRI
Cardiac Cath
MVP
Click-murmur syndromeEtiology unknown - possibly congenitalUsually asymptomatic May be associated with
nonspecific chest pain dyspnea fatigue palpitations
MVP
Characteristic midsystolic click may be multiple, often followed by late
systolic murmur accentuated in standing position
Most commonly affects women 10% of cases - healthy young women many thin some with minor chest wall deformities
MVP
Usually no sequelae if only midsystolic click present
significant mitral regurgitation may develop in cases with late or pansystolic murmur (due to rupture of chordae tendineae)
MVP
Need for valve replacement increases with age men more than women require surgery 2% of patients over age 60 with
significant regurgitation require surgeryTo reduce risk of endocarditis -
antibiotic prophylaxis prior to dental work or surgery
MVP
Aggressive management necessary in cases of symptomatic ventricular tachycardia
Diagnosis primarily clinical - can be confirmed by echocardiogram
MVP
With MVP there is an increased incidence of - sudden death dysrhythmias TIA for persons under age 45
MVP
In cases of MVP w/o mitral regurgitation at rest, exercise provokes mitral regurgitation in 32% of patients
this is a predictor for a high risk of morbid events
Mitral regurgitation due to papillary muscle dysfunction/MI
Mitral regurgitation may subside as left ventricular dilatation diminishes or the infarction heals
Transient (sometimes severe) regurgitation may occur after an MI
In cases of persistent severe regurgitation, poor prognosis with or w/o surgery
Secondary Mitral Regurgitation
Papillary muscle dysfunction or dilation of the mitral annulus in patients with dilated cardiomyopathy of any origin
Valve replacement generally contraindicated due to poor risk:benefit ratio
However, valve replacement in cases where the Left EF >30% have shown good result in some studies
Aortic Stenosis
Aortic Stenosis
Blood flow into the aorta is obstructed, producing progressive LVH and low cardiac output
Most commonly, this is caused by progressive valvular calcification In younger patients with congenital
bicuspid valve In the elderly with normal three-cusp
valves
Aortic Stenosis
In the elderly the aortic valve becomes increasingly sclerotic and eventually stenotic
Degenerative valve disease is three -four times more frequent in men than women
More common in smokers and hypertensives
Aortic Stenosis
Congenital heart disease - most common cause
Rheumatic heart disease - second most common cause
degenerative heart disease (calcific aortic stenosis) 3rd most common cause overall Most common cause > age 70
Aortic Stenosis
Treatment surgery is indicated in all symptomatic
patients exceptions -
declining left ventricular functionvery severe left ventricular hypertrophyvery high gradientsseverely reduced valve areas
Aortic Stenosis
Anticoagulation with warfarin is required for mechanical prostheses but not essential with bioprosthesis
bioprosthetic valves undergo degenerative changes and usually require replacement with 7-10 years - newer ones may be more resilient
Aortic Stenosis
Ross procedure switching the patient’s pulmonary valve
to the aortic position, placing a bioprosthesis in the pulmonary position
(bioprosthesis do not deteriorate as fast on the right side of the heart)
This procedure has produced excellent results without anticoagulation
Aortic Stenosis
Percutaneous balloon valvuloplasty short term reduction in severity restenosis recurs rapidly in most adults
with calcified valves used on poor candidates for surgery or
to stabilize high risk patients prior to surgery
Aortic Stenosis
Classic triad of symptoms dyspnea chest pain syncope
Aortic Stenosis
Dyspnea is usually the first symptom, followed by paroxysmal nocturnal dyspnea, syncope on exertion, angina, and MI
Aortic Stenosis
Sudden death, usually from a dysrhythmia, occurs in 25% of cases
x-ray- early on - normal, eventually LVH and findings of CHF are evident if the valve is not replaced
ECG-demonstrates criteria for LVH, left or right bundle branch block is also present in 10% of cases
Aortic Stenosis
Murmur - harsh systolic ejection murmur
Heart sounds paradoxic splitting of S2, S3, and S4 may
be present; pulse of small amplitude; pulse has a slow rise and sustained peak
Aortic Regurgitation(Chronic Regurgitation)(Aortic Incompetence)
Aortic Regurgitation
20% of cases acute in natureInfective endocarditis - accounts for
majority of casesaortic dissection at the aortic root
causes the remainder of cases
Aortic Regurgitation
In acute cases, sudden increase in backflow of blood into the ventricle raises left ventricular end diastolic pressure, which may cause acute heart failure
Rheumatic heart disease and congenital disease cause the majority of chronic cases
Aortic Regurgitation
In acute disease - dyspnea most common presenting
symptom (50% of cases) many cases have acute pulmonary
edema with pink frothy sputum fever, chills - if endocarditis cause
Aortic Regurgitation
Dissection of the ascending aorta typically produces a tearing chest pain - may radiate between the shoulders
ECG changes w/aortic dissection - ischemia or findings of acute inferior MI - suggestive of right coronary artery involvement
Aortic Regurgitation
Chest xray- in acute state demonstrates acute pulmonary edema with less cardiac enlargement than expected
Aortic Regurgitation
In chronic disease, the ventricle progressively dilates to
accommodate the regurgitant blood volume
Marked peripheral vasodilation
Aortic Regurgitation
Chronic regurgitation 1/3 of patients have palpitations
associated with a large stroke volume and/or premature ventricular contractions
Frequently, these sensations are noticed in bed
Aortic Regurgitation
Chronic Regurgitation wide pulse pressure with prominent
ventricular impulse water hammer pulse may be noted
(peripheral pulse that has a quick rise in upstroke followed by peripheral collapse)
Aortic Regurgitation
Murmur high pitched blowing diastolic murmur
immediately after S2
Heart Sounds S3 may be present; wide pulse pressure
Aortic Regurgitation
An association between the appetite -suppressant drugs (fenfluramine and phentermine or dexfenfluramine) has also been found for aortic incompetence
Tricuspid Stenosis
Usually rheumatic in originshould be suspected when right
heart failure appears in course of mitral valve disease - marked by hepatomegaly, ascites, and dependent edema
May also occur in carcinoid syndrome
Tricuspid Stenosis
Typical diastolic rumble along lower left sternal border mimics mitral stenosis
in sinus rhythm, a presystolic liver pulsation noted
Echocardiography & dopplerCardiac Cath - diagnositic
Tricuspid Stenosis
Surgical options valvotomy prosthetic valve replacement balloon valvuloplasty (experience
limited) may be initial procedure
Tricuspid Regurgitation
Right ventricle overload - result of left ventricular failure of any cause
occurs in conjunction with right ventricular and inferior MI
IV drug users - tricuspid valve endocarditis and regurgitation common
Tricuspid Regurgitation
Other causes carcinoid syndrome lupus erythematosus myxomatous degeneration of the valve
(associated with MVP) Ebstein’s anomaly
Tricuspid Regurgitation
Signs/symptoms identical to those of right ventricular
failure In presence mitral valve disease -
early onset right heart failureharsh systolic murmur - lower left sternal
border - (separate from mitral murmur)
Tricuspid Regurgitation
Prominent regurgitant systolic v wave in right atrium and jugular venous pulse
regurgitant wave, systolic murmur increased with inspiration
Inspiratory S3 may be present
when secondary to mitral valve disease or other left sided disease my regress when underlying disease corrected
Tricuspid Regurgitation
Surgical repair valve repair or valvuloplasty of tricuspid
ring preferred to valve replacement
Questions ??
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