2. DISEASES OF THE HEART VALVES
A diseased valve may be narrowed (stenosed) or may fail to close
adequately, and thus permit regurgitation of blood. 'Incompetence' is a less
precise term for regurgitation or reflux, and should be avoided.
Principal causes of valve disease
a. Valve regurgitation
Congenital
Acute rheumatic carditis
Chronic rheumatic carditis
Infective endocarditis
Valve ring dilatation (e.g. dilated cardiomyopathy)
Syphilitic aortitis
Traumatic valve rupture
Senile degeneration
Damage to chordae and papillary muscles (e.g. MI)
3. b. Valve stenosis
Congenital
Rheumatic carditis
Senile degeneration
Doppler echocardiography is the most useful technique for assessing
valvular heart disease but may also detect minor and even 'physiological'
abnormalities, such as trivial mitral regurgitation.
Disease of the heart valves may progress with time and selected patients
require regular review every 1 or 2 years, to ensure that deterioration is
detected before complications such as heart failure ensue.
Patients with valvular heart disease are susceptible to bacterial
endocarditis, which can be prevented by good dental hygiene.
The routine use of antibiotic prophylaxis at times of bacteraemia, such as
dental extraction, is no longer recommended.
Rheumatic heart disease
4. Causes
1. Chronic rheumatic heart disease
Chronic valvular RHD develops in about ½ of the
patients affected by rheumatic fever with carditis.
About 2/3 of these cases are females.
Mitral valve is affected in >90% of cases followed by
Aortic valve, tricuspid valve and then pulmonary
valve.
RHD is the most common acquired heart disease
with the left sided part of the heart affected more
than the Rt. The main pathology is progressive
fibrosis.
5. Valvular disorders are of two types:
Stenosis – Failure of valves to open completely
during diastole.
Insufficiency / incompetence/ regurgitation –
Failure of a valve to close completely during systole
resulting in regurgitation of blood.
6. 2.Other cause of valvular heart disease
Infective endocarditis ( IE)
Non bacterial thrombotic endocarditis.
Liebman’s sacks endocarditis – specifically in SLE
Syphilitic valvulitis
Calcific aortic valve stenosis
Calcification of mitral annulus
Myxomatous degeneration / floppy valve syndrome
Carcinoid heart disease.
7. Mitral stenosis
Mitral stenosis (Ms) is almost always rheumatic in origin. About 2/3 of
cases are female patients.
Incidence – Declining in developed world but is still a problem in
developing nations.
The latent period between rheumatic carditis and the development of
symptomatic Ms is about 2 decades.
Causes
RHD
Congenital heart disease
Mucopolysaccharidoses
Endocardial fibroelastosis
Malignant carcinoid
Prosthetic valve
8. Pathology
The valves are diffusely thickened by fibrosis and are calcific
especially towards the closing margins.
There is adhesion of mitral commissure, fusion and shortening of
chordae tendinae. Valvular cusps become rigid which lead to
narrowing at the apex of the tunnel shaped valve (fish mouth valve
or button hole).
Initial insult is rheumatic but later changes result from trauma to
valves caused by altered flow pattern.
Calification of stenotic mitral valve immobilizes the leaflets and
narrows the leaflets further. Thrombus formation and arterial
embolism may arise from a calcific valve but more often result from
dilated left atrium especially in patients with A. fib.
In normal adults the mitral valve is about 5cm2 but in Ms, it
decrease to about 1cm2 (critical ms).
9. This results in increased Lt atrial pressure from about 12mmHg to
about 25mmHg→ dilatation of Lt atrium. This eventually
compromises the pulmonary fxn.
The chief symptoms of ms is an increase in heart rate which
shortens in diastole more than systole which diminishes the time for
flow across the mitral valve ( A decrease in EDV –→↓CO →↑ HR as
a compensatory mechanism).
NB: Mitral valve; Normal orifice 4-6cm2, Mild ms 2-4cm2, Mod. ms
1-2cm2 ,Severe ms (critical) < 1cm2
A gradual increase in pressure → pul. HTN but a rapid increase in
pressure →pul. oedema.
Tachycardia including that from increased transvalvular gradient
→increased pressure.
Atrial fibrillation results from problems in conduction and enlarged
Lt Atrium. A. fib is the commonest cmx of ms. Thrombosis is
common →embolic stroke.
10. In the Lt ventricle, the diastolic pressure & ejection fraction are normal in isolated
ms. In ms and sinus rhythm, the elevated Lt atrium & pulmonary artery wedge
pressure exhibit a prominent atrial contraction with an a & y waves and a gradual
increase in pressure; features of cor. pulmonale.
Usually the a wave is due to atrial contraction. Pul.arterial pressure is elevated at
rest and rises further during exercise due to ↑ HR with little time during diastole
→20 elevation of RV diastolic pressures and volume. The RV will have an increased
end diastolic pressure and volume. Co in mod ms is normal at rest but CO is
abnormal at rest in severe ms.
- It fails to rise or decline during activity. In HTN clinical haemodynamic
features of ms are influenced by;-
i) Passive backward transmission of elevated Lt atrial pressure.
ii) Pulmonary arteriolar constriction triggered by Lt atrium and pul. venous
HTN.
iii) Interstitial oedema in the walls of pul. vessels.
iv) Organic obliterative changes in the pul.vascular bed.
v) Severe pul. HTN results in TR and pul. incompetence & Rt sided heart
failure.
11. Symptoms
Breathlessness (exertional) due to pul. congestion & HTN
Fatigue due to ↓CO.
Oedema and ascites due to Rt heart failure
Palpitations – A. fib
Haemoptysis due to congestion and PE
Cough due to pul. HTN.
Chest pain due to pul. HTN.
Symptoms of thromboembolic cmx; Stroke, ischaemic
limbs
Emboli can even go to kidney, spleen or coronary
circulation.
Pt may just present wth infective endocarditis.
12. Signs
General exam – low vol pulse; may be irregularly irregular. May have
oedema, JVP + cyanosis.
Orthopnoea.
Atrial fibrilation
Mitral facies – malar (check) flush, darkening over maxillar because of
vasoconstriction.
Palpable loud P2, Lt sternal border heave because of Lt ventricular
enlargement.
Apex is at 5ics slightly medial to mid-clavicular line – Tapping apex but not
displaced.
Loud S1, opening snap, rumbling mid –diastolic murmur (Graham Steel
murmur may occur). TR murmur, Lt sternal loud P2 on auscultation.
Crackles, rhonchi due to cardiac asthma.
Signs of raised pul. capillary pressure; creps, pulmonary oedema, pleural
effusion.
P/A – pulsating tender hepatomegally + ascites.
13. Investigations
1.ECG – Lt atrial hypertrophy (P. mitrale; broad M shaped
P- wave).
Rt. ventricular hypertrophy (+ve V1 V2 deflection).
May see atrial fibrillation.
2.CXR – Enlarged Lt atrium, signs of pulmonary
congestion.
3.Echo – Thickened immobile cusps, reduced valve area,
decreased rate of diastolic filling of the Lt ventricle
4.Doppler echo – To determine pressure gradient across
the mitral valve is a definitive evaluation of ms, pulmonary
artery pressure and Lt ventricular fxn can be assessed.
5.Cardiac catheterization – Assessment of co-existing
coronary artery disease and MR.
14. Management
1.Manage heart failure
Diuretics
Digoxin
Beta blockers
Rate limiting calcium antagonists for controlling A. fib ( Rate control)
↓Salt diet
2.Anticoagulate to prevent systemic thromboembolism
3.Give penicillin – prophylaxis against rheumatic fever,prophylaxis against infective
endocarditis,Prophylaxis for dental or surgical procedures.
4.Management of A. fib; Anticoagulate, Rhythm control,Rate control
5.Surgery – Mitral valvectomy or valve replacement especially where there are cmxs;
A.fib, HF, Thrombormbolism
Prognosis
-Depends on the degree of ms
-Mild stenosis – good prognosis
15. Mitral regurgitation
Def. Mitral regurgitation (MR) refers to abnormal leaking / backflow
of blood from the Lt ventricle to the Lt atrium.
Aetiology
Chronic RHD is the cause of severe MR in about 1/3 of cases.
It occurs more in males than females.
Rheumatic process produces rigidity, deformity and retraction of
the valve cusps and commissure fusion. This causes shortening,
contraction & fusion of the chordae tendinae.
Congenital annomally – most often as endocardial cushions ( Atrio
–ventricular cushion defects)
Secondary to ischaemia – As a sequence of ventricular remodelling
or fibrosis of papillary muscle in patients with healing MI. MR
develops acutely with acute infarction involving the base of a
papillary muscle. Transient MR also occurs in periods of ischaemia.
16. Secondary to infective endocarditis
Mitral valve prolapse (floppy mitral valve - mostly
degeneration with calcification of mitral annulus.
This is one of the causes of mild mitral regurgitation.
Trauma to mitral valve
Lt ventricular systolic dysfxn.
HOCM(Hypertrophic cardiomyopathy)
17. Pathophysiology
Severe MR is often progressive with enlargement of
the Lt atrium and later Lt ventricular enlargement.
There is resistance of LV emptying which is reduced
in MR. The LV is decompressed into Lt atrium
during ejection. There is ↓Lt ventricular size during
systole.
In acute MR, there is initial compensation but LV
regurgitation increases progressively with
deteriorating LV fxn →decreased forward output.
NB: If ejection fraction is low in Echo, then think of
severe MR.
18. Symptoms
Mild –mod MR – Asymptomatic (CO still normal)
Fatigue due to ↓ CO
Palpitations ( A. fib, stroke volume)
Breathlessness ( CO & backward pressure to pul)
Exertional dyspnoea ( pul. venous congestion)
Orthopnoea – most prominent complaint
Angina
19. Signs
Normal volume pulse in mild- mod MR
Low volume pulse in severe MR
Oedema
Increased JVP in severe MR
Apex usually displaced, heaving apex (hyperdynamic
precordium), may have an S3 gallop.
S1 usually reduced or soft.
Pansystolic murmur (murmur throughout systole) that
radiates to axilla.
+ signs of pul. HTN and Rt heart failure in severe MR.
20. Grading of murmurs
Graded 1 -6, usually according to loudness
Grade 1 – soft & not heard to most people.
Grade 2 – soft but detectable
Grade 3 – moderate, no thrill
Grade 4 – loud, thrill just palpable
Grade 5 – very loud, thrill easily palpable
Grade 6 – very very loud, can be heard even without
placing stethoscope
21. Investigations
1.ECG / Echo
P –Mitrale, LV enlargement
QRS in V5 V6 (SVI, <35m)
LVH QRS > 35mm
Tall R- waves, RVH can still occur
2.CXR – Cardiomegally enlarged LV, Lt. atrium, features of
pul. oedema
3.Echo- increased Lt ventricular vol.
4.Doppler echo –measures the regurgitant vol.
5.Others -cardiac catheterization, MRI
22. Treatment
Depends on the acuteness of MR and the associated signs of
haemodynamic defects
A)Acute MR – Usually with mitral rupture
-Immediate Rx with mitral valve replacement
-Balloon valvoplasty
B)Medical management
-Diuretics
-Vasodilators to symptomatic patients
i)Normotensive pressures; nitroprusside
ii)Chronic MR; ACE- I & Hydrallazine. These vasodilators usually delay the
surgical treatment. Limit use of vasodilators in patients with hypotension.
-Manage A.fib if present; Rate of rhythm control
-Give anticoagulants therapy
-Antibiotic prophylaxis for infective endocarditis
23. C)Surgical management
-Mainstay of Rx
-Mitral valve replacement or repair. This cannot be
done once severe MR has occurred because
haemodynamic changes will not be reversed.
- Indications for surgery
1. Progressive radiological cardiac enlargement
2. Worsening symptoms
3. Mitral valve prolapse
4. Severe MR even if asymptomatic
24. Aortic stenosis
Normal aortic valve aperture 3-4cm2
Aortic stenosis (AS) occurs in ¼ of all patients with chronic valvular
disease. About 80% of adults are asymptomatic and are usually males.
Aetiology
A)Adults
Aortic cusps calcification –senile calcification is the commonest cause.
Degenerative changes
Rheumatic heart disease
About 30% of patients are >65yrs and exhibit aortic valve sclerosis
Histology – inflammatory changes in valve similar to atherosclerosis.
B) Children
Congenital ( biscupid valve, Williams syndrome)
25. Pathophysiology
Obstruction of Lt ventricular outflow produces a systolic pressure gradient
from Lt Ventricle to aorta. The LV outflow is maintained by concurrent
LVH→↓forward normal systolic stress developed by the myocardium.
A large transventricular pressure may exist for many years. LVH increases
myocardial O2 demand leading to ischaemia.
Risk factors
-Age
-Male sex
-Smoking
-Diabetic
-HTN
-Increased LDL, HDL
-Increased CRP
-Congenitally affected valves may be involved at birth.
26. Symptoms
The 3 classic symptoms of AS are
1.Syncope ( dizziness, fainting attacks) due to ↓CO
2.Angina – due to ↓O2 supply.
3.Heart failure / CCF features
-Others- cardiac death (sudden cardiac death) is common in these patients.
Signs
Slow or sustained upstroke arterial pulse
Low vol. pulse
Apical carotid delay
Delayed pulse between radial & brachial artery
Ejection systolic murmur (upper Rt sternal border) which radiates to the carotids
(neck) bilaterally. This is due to turbulent flow over carotids. The murmur increases
when patient is squatting & increases when standing due to increased venous
return.
Isometric muscular contraction distinguishes HOCM
Murmur is louder during expiration
S2 is softer
Apex beat – Not displaced
27. Peripheral signs
-Slow rising small carotid pulse
-Narrow pulse pressure, sustained thrusting apex beat
because of LVH.
Diagnosis
1.ECG – LVH, ST wave changes because of angina
2.CXR – cardiomegally
3.Echo – Evaluates aortic valve, thickened calcified
aortic valve, bicuspid calcified aortic valve
28. Treatment
A.Medical
-Hardly useful in these patients
-Stabilizes with prostaglandin infusions
-Ionotropic support
-Statins if cause is calcific
-ACE – I – To decrease preload
-Prophylaxis for IE
-HF in AS – manage with valve replacement
B.Surgical
-Aortic valve replacement – adults
-Balloon valvoplasty in children
NB: Valvular surgery is a must in all these patients with AS.
Complications
Infective endocarditis
Sudden cardiac death
29. Aortic regurgitation
Leaking of the aortic valve that causes blood to flow in reverse direction during
diastole.
It is a fairly common condition in our set up due to rheumatic heart disease.
Causes
1.Valvular causes
i)Congenital e.g. Bicuspid valve
ii)Acquired disease; Rheumatic heart disease, Infective endocarditis
2.Annulus dilatation commonly due to;
-Syphilis
-Aortic dissection
-Seronegative arthritides e.g Ankylosing spondilitis, Reiters syndrome, psoriatic
arthropathy & reactive arthritis.
-Marfans syndrome
-Osteogenesis imperfecta
-Rheumatoid arthritis
-SLE
-Appetite suppressants e.g. fenfluramine, phentermine etc.
30. Aortic regurgitation may be acute or chromic. Acute
AR is commonly due to valve rupture especially
following trauma
31. Pathology
Regurgitation of blood through the aortic valve
results in compensatory increase in EDV and
increased preload. As the heart is stretched, it sends
more blood to systemic circulation. However, this is
usually short term. With time the LV dilates and
hypertrophies in an effort to meet the demands.
Consequently decrease in diastolic pressure leads to
decreased myocardial oxygenation and ischaemia.
32. Clinical features
The course of the disease may run for 10 – 15yrs before
patients become symptomatic. Significant symptoms
occur late and do not develop until left ventricular failure
occurs.
1. Symptoms – mild – mod. AR; Dyspnoea,
Palpitations
-Severe AR – Angina; not responding to
nitrates
-Easy fatigability, diaphoresis,
breathlessness or features of HF.
NB: Arrhythmias are relatively uncommon
33. Signs
Pulses:
Large volume or collapsing pulse (water hammer pulse).
Low diastolic and wide pulse pressure
Bounding peripheral pulses
Features of hyperdynamic flow:
Piston shot sounds over femoral artery ( Traube’s sign)
Capillary pulsation in nail beds ( Quincke’s sign)
Head nodding with each heart beat ( de musset’s sign)
Carotid pulsation ( Corrigan’s sign)
Femoral diastolic murmur as blood flows backwards in diastole ( Duroziez’s sign)
Parastermal heave
Displaced heaving apex
Thrill radiating to carotids
Murmurs
High pitched early diastolic murmur best heard in Lt sternal boarder 4ics. The murmur has a decreasing
crescendo due to reduced flow in diastole.
Mild diastolic murmur of Ms
Austin flint murmur (in severe AR) best heard with patient leaning forward and breathe held in expiration.
-Others – pre-systolic impulse, fourth heart sound heart (S4 gallop), pulmonary venous congestion
34. Investigations
Most AR are usually peaked clinically
1.ECG – Initially normal, Later LVH, Lt Axis deviation,
features of Lt. ventricular strain (inverted T- waves which
are suggestive of ischaemia.
2.CXR – Cardiomegally, dilated ascending aorta,
pulmonary oedema
3.Doppler Echo – Is diagnostic and assesses degree &
extent of aortic dilatation. May need serial echo for follow
4.MRI – R/o Underlying cause
5.Cardiac catheterization – To assess degree of
regurgitation & anatomy of aortic root.
This may not be required
35. Treatment
1. Aortic valve replacement
Indications:
-EF <55%
->5.5cm end diastolic diameter
-> 55m/s EDV
NB: Must do Echo every 6/12 to determine ejection fraction in
patients with mild-mod AR. Normal EF must be above 60% -
70%
2. Medical – symptomatic relief; Nitrates, Beta blockers, CCB
3. Treatment of underlying cause e.g. syphilis, RHD etc.
4. Prophylaxis against infective endocarditis even if a prosthetic
valve replacement has been performed.
36. RIGHT HEART VALVE DISEASE
Tricuspid stenosis
- Is rare and occurs more in women than men.
- Ts is usually due to rheumatic heart dz and is nearly always
associated with mitral & aortic valve disease. Also seen in carcinoid
syndrome.
Features
- Fatigue
- Ascites, abdo. pains
- Hepatomegally
- Peripheral oedema
- Giant a wave & slow descent in JVP
- Rumbling mid-diastolic murmur – louder in inspiration heard best
over lower left sternal border.
- Opening snap
Management: Doppler echo, CXR, Diuretics, ↓salt intake, Valve repair
37. Tricuspid regurgitation
A fairly common problem
Causes
1. Functional (secondary); RV dilatation due to LVF, Myocardial
infarction, Cor. Pulmonale, Pul. Hypertension
2. Organic / primary; RHD, IE especially IV drug users, Carcinoid
syndrome, Ebstein anomaly (congenitally malpositioned tricuspid
valve), ASD, AV canal etc
Features
Symptoms – Non specific and relate to reduced forward flow and
venous congestion. They include fatigue / tiredness, hepatic pain
due to hepatic enlargement, pain on exertion, giant V waves &
prominent Y descent, normal X descent in JVP. Pulsatile
hepatomegally, ascites and jaundice
39. Pulmonary stenosis
Usually congenital – Turners syndrome, Normans
syndrome, William syndrome, Fallot’s tetralogy,
rubella)
Acquired causes- Rh. fever, carcinoid sydrome
Ps may be valvular, subvalvular or supravalvular
40. Features
- Dyspnoea, fatigue, oedema, ascites
- Dysmorphic facies (cong. causes), prominent a wave in
JVP, RV heave.
- Ejection systolic murmur that radiate to Lt. shoulder
- Widely split S2
- CXR – post stenotic dilatation of pul. Artery. Oligaemic
lung fields, RV/RA hypertrophy.
- ECG – P.pulmonale, RVH, RBBB
- Cardiac catheterisation is diagnostic
Management
Balloon valvotomy or valvoplasty
41. Pulmonary regurgitation
Usually caused by pulmonary hypertension
It may complicate Ms →early diastolic decrescendo
murmur at Lt sternal border that may be difficult to
differentiate from aortic regurgitation (Graham steel
murmur).
PR rarely causes symptoms and treatment is rarely
necessary.