Tuesday, October 11, 2016

Heart Murmurs and Valvular Heart Disease

Heart Murmurs/Valvular Heart Disease*
  • Most common causes of mitral/aortic valve disorders are congenital defects; other causes include rheumatic heart disease, connective tissue disorders, infection, sensile conditions
  • Most common presenting symptoms: dyspnea, fatigue, decreased exercise tolerance
    • Other: Cough, rales, paroxysmal nocturnal dyspnea or hemoptysis, hoarseness
    • Physical exam - heart murmur +/- palpable thrill  
  • Diagnostic Studies
    • EKG - not useful for specific diagnosis → shows chamber hypertrophy
    • CXR
      • Aortic → left sided atrial enlargement, ventricular hypertrophy
      • Mitral → atrial enlargement only
    • Echo (transesophageal) and cardiac cath → definitive
  • Treatment
    • Surgical repair or replacement of defective valve
    • Good exercise tolerance → diuretics and vasodilators for pulmonary congestion and digoxin or BB for dysrhythmias
    • Anticoagulant therapy for thromboemboli prophylaxis
    • Antibiotics to prevent endocarditis and recurrent rheumatic fever


Mitral Valve Prolapse

Regurgitant flow across mitral valve
Decreased left ventricular volume results in earlier prolapse and click heard earlier in systole, closer to S1

Increased left ventricular volume results in delayed prolapse, click heard later in systole

Thin females with minor chest wall deformities

Associated: Ehlers-Danlos, Marfan Syndrome, Mitral Regurgitation
1. Mid-systolic click
2. Followed by a mid-to-late systolic murmur (mitral regurgitation)
3. Loud S2

“Click” is caused by prolapse of leaflets into left atrium and tensing of mitral valve apparatus
1. Maneuvers that increase left ventricular end diastolic volume (preload)/worsen: seated/standing → squatting
2. Maneuvers causing delay in prolapse: handgrip, standing from seated position, valsalva


Health Maintenance
1. Leads to mitral regurgitation
2. Predisposed to infective endocarditis
3. ADA no longer recommends prophylactic antibiotics for MVP


Mid-systolic (HAPI) Murmurs
Hypertrophic Cardiomyopathy
Asian descent
Elderly (distinct form)

Most: autosomal dominant trait

1. Systolic ejection, crescendo-
decrescendo harsh murmur
2. Heard best at LSB


1. Radiation: LSB
2. Decreased (better) with: squatting, lying down or straight leg raise; sustained handgrip
3. Worse (aggravated) with: exercise, valsalva, standing -Decreases preload and afterload
1. EKG: nonspecific ST and T wave changes, septal Q waves, LVH
2. Echo (KEY): LVH, asymmetric septal hypertrophy, small left ventricle, diastolic dysfunction
3. Bisferious pulse (carotid pulse with 2 upstrokes)
Aortic Stenosis
Elderly, syncopal episodes

Narrows valve opening, impeding the ejection function of the left side of the heart

Most common valvular disease in US
1. Crescendo-
decrescendo harsh systolic ejection click
2. Paradoxical split S2
3. Best heard on right near base of heart
4. Severe: Brisk upward deflection of carotids
-Thready carotid pulse
1. Radiation: carotids
2. Decreased (better) with: squat → stand
3. Worse (aggravated) with: sit, lean forward and squatting
1. EKG: Left ventricular hypertrophy
Pulmonary Stenosis
Congenital disorder

Left sided HF: DOE, jugular pulsation, parasternal lift
1. Preceding systolic sound during expiration
2. Systolic murmur
3. Best heard at 2nd-3rd LICS
1. Radiation: Left shoulder
2. Worse (aggravated) with: inspiration
1. EKG: right axis deviation
Innocent (Still’s) Murmur
Most common murmur of childhood (2-7 years of age)
1. ‘Musical’ or ‘vibratory’ Grade I-III early systolic murmur
2. Short, high-pitched
3. Loudest midway between apex and LLSB
1. Decreased (better) with: squat → stand, valsalva, sitting, inspiration  
2. Worse (aggravated) with: squatting, supine, fever, anemia, sinus tachycardia



Holosystolic (MTV) Murmurs
Mitral Regurgitation
Associated:  acute rheumatic fever, Marfan Syndrome

Retrograde blood flow and volume overload of the left atrium
1. High-pitched, holosystolic murmur
2. Heard best at Apex

1. Radiating to left sternal border (Axilla)
2. Worse with: isometric hand grip
3. Reduced (better) with: valsalva
1. EKG: left axis deviation or LVH
Tricuspid Regurgitation
H/o pulmonary HTN and cor pulmonale
1. Blowing holosystolic murmur
2. Heard best at LLSB
3. NO EJECTION CLICK
4. Opening snap + diastolic murmur
5. S3 may be present
6. Increased JVP
7. Palpable venous pulse in liver
1. Radiation: RSB, 5th ICS
2. Worse with: inspiration
3. Reduced (better) with: valsalva
1. EKG: right axis deviation
Ventricular Septal Defect (VSD)
L-to-R during systole
1. Harsh high-pitched holosystolic murmur
2. Heard best in 3-4th Left-ICS (parasternal line)
1. Radiation: diffuse
2. Worse with: isometric hand grip
3. Reduced (better) with: valsalva



Diastolic (ARMS) Murmurs
Aortic Regurgitation
Younger pt with h/o Marfan’s syndrome or older patient  

Volume overloading due to retrograde blood flow into the left ventricle

Classic: diastolic murmur at RSB due to backflow of blood across aortic valve
1. High-pitched Blowing diastolic murmur  
2. Decrescendo- crescendo (“V”) murmur
3. Heard best at left sternal border
1. Radiation: apex
2. Worse with: sitting up, leaning forward, exhaling & holding
1. Bounding “water hammer” pulse
2. Wide pulse pressure
3. Rumbling sound at apex (Austin Flint Murmur) - retrograde blood across aorta mixes with anterograde blood from left atrium
Mitral
Stenosis
Common after rheumatic fever

Impedes blood flow between left atrium and ventricle
Enlarged left ventricle
1. Loud first heart sound: wide closing excursion of leaflets
2. Prominent P2 of second heart sound (split S2): elevated pulm-art pressures
3. Opening Snap: sudden tensing of leaflets after they’ve completed their opening excursion
4. Low pitched (Mid)-diastolic rumble - increased flow across stenotic MV during atrial contraction
5. Heard best at apex
1. Radiation: none
2. Worse with: left lateral decubitus position (exhale & hold)
1. Hemoptysis, presents in 30-40s

Complications
1. Leads to pulmonary hypertension and heart failure → high LA pressures = high pulmonary vasculature and right heart pressures


Congenital Heart Disease
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Cyanotic Defects
Tetralogy of Fallot
6-10%
R → L shunting
Crescendo-
decrescendo holosystolic at LSB
1. Right ventricular hypertrophy
2. Pulmonic Stenosis
3. Overriding aorta
4. VSD

1. Cyanosis
2. Blubbing
3. Increased RV impulse at LLSB
4. Loud S2
1. Radiation: back
2. Reduced with: squatting (increases SVR)



EMERGENCY
1. Polycythemia; tet spells (hypercyanotic) include extreme cyanosis, hyperpnea, and agitation
2. Tet-spells: irritability, tachypnea, cyanosis worse with exertion (feeding or intense crying)
Pulmonary Atresia
1-3%

Presentation depends on presence of tricuspid regurgitation

TX: Indomethacin
1. Cyanosis with tachypnea at birth
2. Tachypnea without dyspnea
3. Hyperdynamic apical pulse
4. Single S1/S2
5. Sudden onset severe cyanosis and acidosis

EMERGENCY

Hypoplastic Left Heart Syndrome
7-9%

More often in males, 25% of cardiac death before age 7
1. Shock
2. Early heart failure
3. Respiratory distress
4. Single S2


Transposition of the great Vessels
5-7%
No exchange between right and left circulation

TX: Prostaglandins
1. Systolic ejection murmur if associated with VSD or pulmonary stenosis
2. Cyanosis in newborn (MC)
3. Tachypnea without respiratory distress
4. If large, sx of CHF and poor feeding
5. Single loud S2

1. Absent LE pulses if aortic arch obst


Non-Cyanotic Defects
  • Mnemonic: All Ventricles Provide Circulation (AVPC)
Atrial Septal Defect
7% of all defects
Cause: patent foramen ovale
1. Wide, fixed splitting of S2
2. Systolic ejection murmur at 2nd LCIS
3. Early to mid systolic rumble

Signs/SX
1. Failure to thrive
2. Fatigue
3. RV heave


VSD
Most common of all congenital heart defects

Outlet VSDs more common in Japanese and Chinese
1. Systolic murmur
2. Symptomatology depends on size of defect - from asymptomatic to CHF
1. Radiation: 3-4th LLSB

PDA
12-15% of significant congenital heart disease; higher in premature infants
1. Continuous (machinery-like) murmur
2. Wide pulse pressure
3. Hyperdynamic apical pulse


Coarctation of the Aorta


TX: PGE to maintain ductus arteriosus
1. Systolic ejection click (may be continuous)
2. Infants - CHF
3. Older children - systolic hypertension or new murmur or underdeveloped lower extremities
1. Radiation: LUSB and left scapular area

1. Differences between arterial pulses and blood pressure in UE/LE is pathognomonic
-BP right arm > left
2. Absent femoral pulse
UE = upper extremity

LE = lower extremity

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