Valvular Heart Disease

J.B. Handler, M.D.

Physician Assistant Program University of New England

              

Abbreviations

VHD- valvular heart disease  RVH- right ventricular hypertrophy  AoV- aortic valve RF- rheumatic fever  MVA- mitral valve area MR- mitral regurgitation AR- aortic regurgitation  PSVT- paroxysmal supraventricular tachycardia HF- congestive heart failure  MVR- mitral valve replacement MS- mitral stenosis LAP- left atrial pressure  MVP- mitral valve prolapse  AS- aortic stenosis PuVR- pulmonary vascular resistance  SEM- systolic ejection murmur RV- right ventricle  LVEDP- left ventricular end diastolic pressure CO- cardiac output TR- tricuspid regurgitation PI- pulmonic insufficiency  PND- paroxysmal nocturnal dyspnea  LSB- left sternal border NSST-T- non specific ST-T PAH- pulmonary artery hypertension  ACE- angiotensin converting enzyme  BE- bacterial endocarditis SV- stroke volume  RF- rheumatic fever

Etiologies of VHD

 Rheumatic valve disease  Congenital, including bicuspid aortic valve.

 Coronary heart disease: MI, papillary muscles   Dilation of the aorta: Aortic root disease Chronic “wear and tear”: aortic sclerosis/stenosis  Dilation of the LV- from any cause: MR  Endocarditis  MV prolapse  Others

Acute Rheumatic Fever: IO

 2/3 all cases - developing countries  Episodes of RF are quite uncommon in U.S., except in immigrants.

 Epidemiology - Identical to that of Group A Streptococcus; children 5-15  Pathogenesis-

oropharyngeal infection

; RF follows the sore throat; usually within 2-3 wks.

 Mechanism - systemic immune process involving Group A strep. antigens; abnormal immune response.

Preventable with adequate Rx of streptococcal pharyngitis.

IO – Interest Only

Diagnosis - Jones Criterion

 Carditis - Pancarditis involving

valves

, endocardium, myocardium and pericardium –

Healing of Rheumatic valvulitis

- fibrous thickening resulting in valvular stenosis or insufficiency   Migratory polyarthritis Sydenham’s Chorea  Subcutaneous nodules  Erythema marginatum

Treatment

 Antistreptoccal Rx until regimen finished; Penicillin IM or oral (10 day course) Erythromycin and others are alternatives  Arthritis/fever - Salicylates  Severe carditis- Glucocorticoids  HF, MR, AI - specific Rx.

 Secondary prophylaxis to prevent recurrences- PCN or alternative until adult.

Cardiac Pressures

4-12 4-12 4-12 8-15 4-12 4-12 4-12 Images.google.com

Mitral Regurgitation-Etiology

 Chronic Rheumatic heart disease  ing frequency  LV dilatation from any cause  Coronary Heart Disease: Papillary muscle dysfunction with ischemia/infarction  Mitral Valve Prolapse  Infective endocarditis

Mitral Regurgitation

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Pathophysiology of MR



Blood regurgitates from LV into LA

.  LV

volume

increases progressively as severity of MR increases.

– Increased blood return to LA: pulmonary veins + regurgitant volume from previous beat.

 LV function- well preserved initially; often deteriorates in later stages as does cardiac output (CO). LV compensates for volume overload via the

Starling mechanism

.  Left atrium (and LV) dilates over time -

LAP

and LVEDP gradually rise  pulmonary congestion –

Afib. common

.

Symptoms

 Often asymptomatic for years  Fatigue, DOE, orthopnea- symptoms of

left sided heart failure

(detailed discussion later in CV system).

 With chronic severe MR –Elevation of pulmonary venous pressure leads to  PuVR  PAH and subsequent Rt Heart failure: hepatic congestion, peripheral edema, etc.

Physical Exam

 Palpation: Systolic thrill may be present at apex depending on turbulence.  Auscultation: S 1 soft or absent;

S 3

significant MR;

Systolic Murmur gallop

is if hallmark - Gr. II-IV/VI

holosystolic

in most cases -radiates to axilla (exception is MVP); murmur is

high pitched

and

blowing

.

Additional Findings

 ECG: LAE; Atrial arrhythmias (Afib).



Echo/Doppler

: LA & LV size; LV function. Can estimate severity of MR; LV often dilates with progressive MR.

 CxR: Late findings - Progressive LVE; HF; pulmonary edema.

CxR- chest x-ray LVE- left ventricular enlargement

Treatment of MR

 Medical - Treatment

depends on severity

.

Once symptomatic: Decreased physical activity and Na restriction. Drug therapy often significantly improves symptoms and patients may do well for many years. –

ACE inhibitors

or other vasodilators:

decrease afterload

and preload.

– Diuretics: decrease preload, Na and volume overload – Inotropic agents: digoxin- limited role

Treatment of MR

 Surgical- Indications: –

Severe MR with Sx

– Dilating LV with progressive dysfunction   EF (even with mild symptoms). – Timing of surgery is important; needs to be done before significant deterioration of LV function/EF.

 Surgical result dependent on pre-existing LV function. Mitral valve repair is preferred to MV replacement.

Mitral Valve Prolapse

 Very common (3-5% adults) - Excessive redundant MV tissue from abnormal connective tissue: –

MVP

- most common form involves MV without major connective tissue disease elsewhere in body. Familial form also exists- autosomal dominant.

– MVP as part of major CT disease (Marfan’s, Ehler’s Danlos) or variations; these disorders are uncommon.

 Pathology- myxomatous degeneration of MV leaflet tissue.  Associated deformities: high arched palate; pectus excavatum.

Mitral Valve Prolapse

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MVP: Pathology

 Mitral regurgitation can develop due to redundant floppy valve leaflets and/or involvement of the MV supporting structures – chordae tendineae.

 Stress on Papillary muscles or chordae is presumed reason for localized and atypical

chest pain

.

 Abnormal valve structure and MR can predispose to infective endocarditis but incidence is very low  antibiotic prophylaxis no longer indicated.

Clinical Features

 Female > male; Sx, when present, commonly occur at ages 15-30.



Most are asymptomatic

; often detected on PE characteristic murmur.

   Most common symptoms when present:

chest pain

(*atypical)

and palpitations.

Arrhythmias common: PAC’s, PVC’s, PSVT, non-sustained VTach.

Sudden death – exceedingly rare  arrhythmias *Atypical – CP unlike the pain/discomfort that is present with coronary heart disease

Physical Findings

 Auscultation:

Mid to late systolic click

(tensing of chordal structures).



High pitched late systolic murmur

best heard at apex.- click and murmur occur earlier and get

louder with maneuvers that decrease LV volume

: standing after squatting, valsalva. Maneuvers that increase LV volume delay the click and soften the murmur: isometric hand grip, squatting.

Additional Findings/Treatment

 ECG: NST-TW changes. Usually in leads II, III, aVF.



Echo/Doppler: Diagnostic

; shows MVP and identifies MR when present.

 Treatment:

Reassurance

; ß-Blockers for chest pain or arrhythmias; additional anti-arrhythmics usually not necessary.

 Infrequently, severe MR develops requiring MV repair (more common in men than women).

Mitral Stenosis

 2/3 females, 1/3 males- only cause is RF.

 About 40% of all cases of RF develop MS.

 Valve leaflets thicken and calcify, commisures fuse; valve orifice narrows; subvalvular supporting apparatus involved.

 Least common rheumatic valvular lesion.

Mitral Stenosis

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Pathophysiology

 Normal MVA - 4-6 cm 2 . Valve leaflets fuse, decreasing valve area. Severe MS < 1 cm 2 .

 LA pressure rises in order to propel blood across the stenotic valve- pressure gradient compared to LVEDP. 

LAP reflected backwards into the pulmonary circulation results in pulmonary venous congestion



pulm capillary congestion



interstitial fluid



dyspnea. Pulmonary arterioles subsequently constrict.

 LV function usually normal. LVEDP normal.

  Chronic severe MS - Elevation of pulmonary vascular resistance (PVR) and subsequent development of

Pulmonary Artery Hypertension (PAH)

.

Chronic PAH  RVH failure.

 RV dysfunction and  CO at rest- usually normal but does not rise adequately with exercise. With severe MS and PAH, CO eventually falls.

Symptoms/Complications

 DOE, orthopnea, PND  pulmonary edema  Findings of Rt Ht failure - late  Atrial arrhythmias: PAC’s,

Atrial



Fibrillation

and Flutter Hemoptysis  ruptured pulmonary capillaries  Atrial Thrombi and embolization - (AFib)

Physical Exam

 Palpation: prominent RV impulse  Auscultation: S 1 if PAH present loud/accentuated; S 2 loud

Opening Snap

of MV-apex, follows S 2 .

Diastolic Rumble

- Follows OS;

low pitched

/apex; length correlates with severity; MR murmur often audible.

Additional Findings

 ECG: LAE/LAA; RAD, RVH (over time) 

Echo/Doppler

: diagnostic-shows abnormal valve motion, estimates the gradient and MVA, defines LA size and LV function.

 CxR: Pulmonary congestion; RVE.

 Cardiac Cath: Documents gradient, MVA, presence or absence of MR and more.

MS - Treatment

 Sodium restriction, diuretics.

 Rate control of Afib or cardioversion.

 Surgery -Mitral valvulotomy - marked symptomatic improvement. MVR only when repair cannot be done (mortality 3-5 %).

 Percutaneous balloon valvuloplasty- alternative to surgery; if successful, avoids or delays need for surgery.

Aortic Stenosis-Etiologies

  Common: 20% all valvular disease; 80% males Bicuspid valve  leaflets thicken, fuse Rheumatic valvulitis

Idiopathic

 leaflets thicken, fuse – Sclerocalcific: chronic wear and tear develops in the elderly  leaflets thicken, fuse 

Note

: Thickening/calcification (without fusing) of the AoV often occurs with aging (

Aortic Sclerosis

)

without progressing to significant aortic stenosis

 Gr II/III murmur. Important to differentiate using history (asymptomatic),

echocardiogram

if needed.

PE

and

Aortic Stenosis

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Pathophysiology

 Obstruction to LV outflow-

pressure overload

.

 Systolic gradient between LV and Ao.

 Obstruction gradual - initially well tolerated;

LV hypertrophy

is compensatory.

 Cardiac Output often normal at rest - does not adequately rise with activity.

 Late in course- LV failure, LVEDP rises, CO falls.

 Myocardial oxygen consumption (MVO 2 ) increases from LVH and high LV pressures.

 Coronary blood flow is impaired from high LV pressures.

  Myocardial ischemia can occur in the absence of *CHD  severe LVH/ high pressures  outstrips coronary blood flow – Associated CHD may be present.

Normal AoV area: 2.5-3.0 cm 2 Critical AS: valve area <0.75 cm 2 *CHD- coronary heart disease

AS Hemodynamics

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Symptoms of AS

 Exertional dyspnea - elevation of LVEDP transmitted backward into pulmonary circuit.

 Angina Pectoris-Increased MVO 2 (pressure overload and hypertrophy) and decreased coronary reserve. *CHD may co-exist but does not have to be present for angina to develop.  Syncope - Peripheral vasodilation with inadequate forward CO with activity or from arrhythmia.

 HF occurs late - very poor prognosis. CHD – coronary heart disease

Physical Exam

 Carotid pulse rises slowly; sustained peak.

 Apex displaced laterally; +/- systolic thrill; systolic ejection sound (click ) variable.

   Aortic valve closure is delayed - fixed or paradoxical splitting of S 2 .

S 4 gallop

common.

Murmur -

SEM (crescendo-decrescendo

)- peaks in mid to late systole depending on severity;

harsh, low pitched

, best heard at base and radiates to carotids – Grade II-IV/VI.

Additional Findings

 ECG:

LVH common

; LAA.



Echo/Doppler

: Diagnostic- identifies LVH, valve calcification and restriction; estimates gradient and aortic valve area.

 CxR: LV prominence, displaced apex.

 Cardiac Cath: Usually necessary prior to surgery; identifies gradient, valve area, LV function and

presence or absence of CAD

.

Natural History: Untreated

 Angina Pectoris -death within 3 years  Syncope - death within 3 years  Dyspnea - death within 2 years  CHF - death within 1.5 years

Treatment

 Medical - Mild to moderate AS without symptoms: Careful F/U; serial echo/doppler studies. begin.

Limited role for meds

once symptoms 

Surgical-

severe or symptomatic AS. Valve replacement with tissue or mechanical valve - Op risk 4%; 60-70% 10 yr. survival; marked symptomatic improvement.

– Ross procedure an option for young patients with AS.

 Ballon valvuloplasty- palliative

Aortic Regurgitation- Etiology

 75% male  Rheumatic Heart Disease  Infective endocarditis on previously deformed valve  Aortic Root disease and dilatation  Bicuspic Aortic Valve (AS more common than AR)

Aortic Regurgitation

AR: Pathophysiology

 Increase in LVEDV (preload): blood returning from LA + regurgitant blood.

 LV dilates- allows increased SV (stroke volume) and adequate effective forward SV (Starling’s law).

 Over time (years) LV function gradually declines and EF (ejection fraction) deteriorates.

Pathophysiology

 LV deterioration often precedes symptoms (reason for serial echo/doppler exams).

 As AR progresses, CO fails to rise adequately with exercise, LV dysfunction worsens  Increased LVEDP  congestion  HF.

pulmonary

AR: History

 Sometimes familial - Connective tissue disease.

 History of RF or infective endocarditis.

 Patient often asymptomatic for 10-15 yrs. with significant AI.

 Symptoms: Palpitations, exertional dyspnea, orthopnea; PND and HF occur later.  Atypical chest pain common.

AR: Physical Exam

   Arterial Pulse - Rapid rising “water-hammer pulse” and collapsing pulse.

“Quinke’s pulse” - alternate flushing and palling of the skin at the nail root.

“Pistol shot” sound over femoral artery in systole.

Derosiez’ sign - to and fro murmur over femoral artery.



Arterial pulse pressure widened

- elevated systolic pressure (often greater than 200mm) and lowered diastolic pressure.

Physical Exam

 Palpation - apex displaced laterally/inferiorly.

 Diastolic Thrill may be present along LSB.

 Auscultation: S2 soft;

S3 common; high pitched blowing diastolic decreshendo murmur (LSB).

 Best heard with diaphragm – patient sitting upright/leaning forward.

 Systolic ejection (increased flow across AoV) murmur.

Additional Findings

 ECG - Increased voltage/LVH develops over time. 

Echo/Doppler

: early on LV contractility normal or increased - later, LV dysfunction; AI jet detectable and semi quantitated by Doppler.

 Cardiac Cath: Identifies severity of AI, degree of LV dysfunction and intra-cardiac pressures. Needed to assess coronary arteries in older adults.

Cath may not be needed in younger patients

.

Treatment of AR

 Medical - very close follow-up; serial Echo/Doppler studies. Same Rx as for CHF:

Afterload reduction with vasodilators (ACEI

, hydralazine). Preload reduction with diuretics; digoxin may be useful in selected individuals.

 Surgical - Timing of surgery is difficult as pts. with AI do not develop symptoms until after the development of LV dysfunction.

Surgery indicated for progressive LV dilatation and dysfunction +/- symptoms.

Surgery

 Aortic Valve Replacement with bioprosthesis (tissue valve) or mechanical valve. Ross procedure an option if young.

 Op mortality dependent on pre-op LV function (5% or greater mortality).