Valvular Heart Disease Flashcards
Examples of diseases affecting the heart
Mitral stenosis
Mitral regurgitation
Aortic Stenosis
Aortic regurgitation
*Clinical presentation of mitral stenosis
Pulmonary hypertension ->
dyspnoea, pink frothy sputum, left atrial dilatation, right ventricular hypertrophy, palpitations.
Malar flush due to low CO.
Opening snap and diastolic murmur.
What causes malaria flush?
Low CO
associated with mitral stenosis due to the resulting CO2 retention and its vasodilatory effects
What is malar flush?
plum-red discolouration of the high cheeks
When listening to heart sound of patient, what would be characteristic of mitral stenosis?
Mid-diastolic murmur
Pathophysiology of mitral stenosis
Inflammation -> Mitral valve thickened/calcified obstructing normal flow from LA to LV.
Therefore LA pressure increases to maintain CO: Raised LA pressure -> LA hypertrophy and dilatation -> palpitations.
Raised LA pressure -> pulmonary hypertension -> RV hypertrophy, dilation and failure with subsequent tricuspid regurgitation.
Raised pulmonary pressure also causes the development of pulmonary capillary oedema (especially with atrial fibrillation)
Aetiology of mitral stenosis
Rheumatic valvular disease (usually Strep pyogenes) - main
Others:
Infective endocarditis (3.3%)
Mitral annular calcification (2.7%)
*Diagnostic tests of mitral stenosis?
CXR: LA enlargement, pulmonary oedema/congestion, occasionally calcified mitral valve.
ECG: AF, LA enlargement, RV hypertrophy
Echocardiography: assess mitral valve mobility, gradient and measure mitral valve area.
What is area of normal mitral valve?
4-6 cm^2
At what size do symptoms of mitral stenosis occur
When mitral valve area is less than 2 cm^2
Treatment of mitral stenosis
- Diuretics (furosemide) - for fluid overload
- Beta-blockers e.g. Atenolol and digoxin which control heart rate and thus prolong diastole for better diastolic filling
- Percutaneous mitral balloon valvotomy
- Excise segments of valve, or mitral valve replacement
Also: Infective endocarditis prophylaxis (amoxicillin?)
(Rate control + anticoagulation)
*Clinical presentation of mitral regurgitation
*Pansystolic murmur (at apex radiating to axilla)
Mid-systolic click and late systolic murmur in mitral prolapse
Deviated apex beat.
Variable haemodynamic effects:
Palpitation due to increased stroke volume
Fatigue and lethargy due to reduced CO
Right heart failure and eventual congestive cardiac failure symptoms.
Dyspnoea
What heart sound would you associate with mitral regurgitation
pan-systolic murmur
Pathophysiology of mitral regurgitation
Mitral valve fails to prevent reflux of blood. Regurgitation into the LA -> increased LA dilation and eventually pressure -> increased pulmonary pressure -> pulmonary hypertension
Progressive left atrial dilatation and right ventricular dysfunction due to pulmonary hypertension.
Progressive left ventricular volume overload leads to dilatation and progressive heart failure.
Pure volume overload due to leakage of blood into left atrium during systole
Aetiology of mitral regurgitation
Due to abnormalities of the valve leaflets, chordae tendinae, papillary muscles or left ventricle.
Most frequent cause is Myxomatous Degeneration (MVP) - weakening of chord tendinae, resulting in a floppy mitral valve that prolapses.
Dilatation of mitral valve annulus (fibrous ring attached to mitral valve leaflets). Mitral valve prolapse. Infective endocarditis. Rheumatic valvular disease. Marfan’s and Ehler-Danlos.
Papillary muscle dysfunction/rupture.
Epidemiology of mitral regurgitation
Second most common valvular condition requiring surgery
Mild physiological mitral regurgitation (MR) is seen in 80% of normal individuals
*Diagnostic test of mitral regurgitation
*Echocardiography:
• Estimation of left atrium and left ventricle size and function
• Also gives valve structure assessment
• Transoesophageal is very helpful
CXR:
• Left atrial enlargement and central pulmonary artery enlargement
ECG:
• May show left atrial enlargement, atrial fibrillation and left ventricle hypertrophy in severe MR
• But NOT diagnostic
Treatment of mitral regurgitation
Repair preferred over replacement (repair when any symptoms at rest or exercise)
Meds:
ACE-inhibitor as vasodilator (smooth muscle relaxer) e.g. ramipril or hydralazine
Beta blocker (Atenolol), calcium channel antagonist and digoxin for heart rate control of AF
Anticoagulation also in AF and flutter
Diuretics e.g. furosemide for fluid overload
*Clinical presentation of aortic stenosis
Any elderly person with chest pain, exertion dyspnoea or syncope (loss of consciousness due to lack of blood).
Slow rising carotid pulse.
Left ventricular hypertrophy -> Prominent 4th heart sound
SAD:
Syncope, angina, dyspnoea (on exertion due to HF).
Heart failure and sudden death
Heart Sounds:
-Ejection systolic murmur
-soft or absent second heart sound
(-loudness does NOT tell you anything about severity)
*What heart sound would you associate with aortic stenosis
Early systolic murmur
Pathophysiology of aortic stenosis
Aortic valve thickened/calcified obstructing normal flow.
Obstructed LV outflow -> Increased afterload -> Increased LV pressure -> Compensatory LV hypertrophy -> Relative ischaemia (of LV myocardium as hypertrophy increases blood demand) -> Angina, arrythmia and LV failure -> Reduced cardiac output.
Aetiology of aortic stenosis
Calcific degeneration:
Calcific aortic valvular disease (CAVD) - calcification of aortic valve resulting in stenosis, mainly in elderly.
(Calcification of a) Congenital bicuspid aortic valve (BAV) - has 2 cusps, not 3 due to genetic disease - most common congenital heart disease
Rheumatic valvular disease.
Epidemiology of aortic stenosis
Most common valvular condition requiring surgery.
Primarily a disease of ageing
Congenital is second most common cause.
Most common cause of valvular disease in western world.
*Diagnostic tests of aortic stenosis
Echocardiography:
- Left ventricular size & function; LV hypertrophy, dilation and ejection fraction
- Doppler derived gradient and valve area (AVA), allows for the assessment of the pressure gradient across the valve during systole.
ECG: LV hypertrophy; LA delay; LV strain pattern seen as:
Depressed ST segments and T-wave inversion in leads I, aVL, V5 and V6
CXR: LV hypertrophy; calcified aortic valve
Treatment of aortic stenosis
Rigorous dental care due to high risk of Infective Endocarditis
Aortic Valve replacement,
Transcatheter aortic valve replacement (TAVI) - percutaneous alternative for surgical replacement,
Surgical valvuloplasty or Balloon valvuloplasty also
Sequelae of aortic stenosis
Left sided HF
Sudden death
*Clinical presentation of aortic regurgitation
Early diastolic murmur at left sternal border
Systolic ejection murmur due to increased flow across the aortic valve.
Austin flint murmur: Fluttering of anterior mitral valve cusp due to regurgitant stream
Asymptomatic until 4th or 5th decade.
Exertional dyspnoea
Palpitations, Syncope, Apex beat is displaced laterally.
Wide pulse pressure, Collapsing (water hammer) pulse, angina, left ventricular failure.
Quincke’s sign; de Musset’s sign; Pistol shot femoral
Pathophysiology of aortic regurgitation
Aortic valve fails to prevent reflux of blood (during diastole). LV hypertrophy to maintain cardiac output (as total volume of blood pumped into aorta must increase).
Progressive dilation leads to HF
Furthermore due to the fact that the remaining blood in the root of the aorta supplies the coronary arteries via the coronary sinus during diastole - regurgitation causes Diastolic blood pressure to fall -> coronary perfusion decreases -> relative ischaemia.
Eventually leads to left ventricular failure.
Aetiology of aortic regurgitation
Main:
Infective endocarditis
Congenital bicuspid aortic valve (BAV)
Rheumatic fever
Aortic root dilatation.
Some rheumatological disorders.
Ascending aortic dissection possible.
Epidemiology of aortic regurgitation
Moderate or severe common after transcatheter aortic valve replacement
*Diagnostic tests of aortic regurgitation
Echocardiography:
• Evaluation of the aortic valve and aortic root
• Measurement of left ventricle dimensions and function
• Cornerstone for decision making and follow up evaluation
ECG: LV hypertrophy (due to volume overload) - tall R waves and deeply inverted T waves in left-sided chest leads
- deep S waves in right-sided leads
CXR:
• Enlarged cardiac silhouette and aortic root enlargement
• LV enlargement
Treatment of aortic regurgitation
Treat underlying cause. Vasodilators (ACE-inhibitor such as Ramipril - improve SV and reduce regurgitation but only if patient is symptomatic).
Valve replacement if symptoms are increasing (enlarging heart on CXR/ECHO, ECG deterioration (T wave inversion in lateral leads).
Consider Infective Endocarditis prophylaxis.
Serial echocardiograms to monitor progression.
A 45 year old lady, who moved to the UK from India 5 years ago, presented with increasing exertional dyspnoea and orthopnoea. On examination, the apex beat is tapping, with a loud first heart sound, and an apical mid-diastolic rumble.
Presentation of what?
Mitral stenosis
What is Percutaneous mitral balloon valvotomy?
For mitral stenosis
• Catheter is inserted into the right atrium vie the femoral vein under local anaesthesia
• The interatrial septum is then punctured and the catheter advanced into the left atrium and across the mitral valve
• The balloon is inflated and puts pressure on valve thereby separating the leaflets thereby increasing the size of the mitral valve opening thus enabling more blood to flow from left atrium into left ventricle
*How does inflammation due to rheumatic fever lead to mitral stenosis
Inflammation due to rheumatic fever leads to commissural fusion and a reduction in mitral valve orifice area, causing the characteristic doming pattern seen on echocardiography
*Mitral stenosis: Why do you get Progressive dyspnoea (and what makes it worse)
due to left atrial dilation resulting in pulmonary congestion (reduced emptying), which is worse with exercise, fever, tachycardia and pregnancy
*Mitral stenosis: Why do you get Haemoptysis
due to rupture of bronchial vessels due to the elevated pulmonary pressure
*Mitral stenosis: Why do you get Right heart failure
due to the development of pulmonary hypertension with symptoms of weakness, fatigue and abdominal or lower limb swelling
*Mitral stenosis: Why do you get Atrial Fibrillation
due to left atrium dilation giving rise to palpitations
*Mitral stenosis: Why do you get systemic emboli
due to atrial fibrillation, most commonly in the cerebral vessels
*Mitral stenosis: Why do you get Prominent “a” wave in jugular venous pulsations
due to pulmonary hypertension and right ventricular hypertrophy
*Mitral stenosis: Why do you get Mitral facies/malar flush
pinkish-purple patches on the cheeks due to vasoconstriction in response to diminished cardiac output
Describe features of the diastolic murmur from mitral stenosis
Heard when blood flows over a valve
Low-pitched diastolic rumble most prominent at the apex
Heard best with patient lying on the left side in held expiration
Longer murmur in more severe stenosis
Describe features of the loud opening S1 snap
Heard at apex when leaflets are still mobile
Due to the abrupt halt in leaflet motion in early diastole, after a rapid initial opening, due to fusion at the leaflet tips
As the valve cusps become more immobile, the loud first heart sound softens and the opening snap disappears
Risk factors of mitral regurgitation
- Associated with females
- Lower BMI
- Advanced age
- Renal dysfunction
- Prior MI
Define blood flow in heart with mitral regurgitation
Backflow of blood from the left ventricle to the left atrium during systole
Natural history generally with mitral regurgitation
- Compensatory phase: 10-15 years
- Once patients ejection fraction becomes less than 60% and/or becomes symptomatic then mortality rises sharply
- Severe mitral regurgitation has a 5%/year mortality rate
Where is aortic valve and how many cusps does it have?
- Located on the left side of the heart and separates the left ventricle from the aorta
- Aortic valve has 3 cusps
- One of two semi-lunar valves
What is normal aortic valve area and when would symptoms of aortic stenosis occur?
- Normal aortic valve area is 3-4cm2
- Symptoms occur when valve area is 1/4th of normal
Types of aortic stenosis
- Supravalvular (above valve) e.g congenital fibrous diaphragm above the aortic valve
- Subvalvular (below valve) e.g congenital condition in which a fibrous ridge or diaphragm is situated immediately below the aortic valve
- Valvular - most common
Risk factors of aortic stenosis
- Congenital bicuspid aortic valve (BAV) predisposes to stenosis and regurgitation - bicuspid valves are more likely to develop stenosis
- Congenital BAV is predominant in males
Can James keep going?
Yes he can!!
Do you need a break
No u fuckin nutter keep going
Could you go out tonight
Yeah u could but ur not gonna u stupid cunt keep revising until ur not a dumb shit
Why is exercise so bad in aortic stenosis
Exercise causes a many-fold increase in cardiac output, however due to the severe narrowing of the aortic valve, the cardiac output can hardly increase - thus, the blood pressure falls, coronary ischaemia worsens, the myocardium fails and cardiac arrhythmias develop.
*Why is dental care so important in anyone with a valvular heart disease
Due to increased risk of infective endocarditis
Why are vasodilators contra-indicated in severe aortic stenosis
due to the fact that they may trigger hypotension and thus syncope
Indications of surgical aortic valve replacement in aortic stenosis
- Any SYMPTOMATIC patients with severe aortic stenosis (include symptoms with exercise)
- Any patient with decreasing ejection fraction
- Any patent undergoing CABG with moderate or severe aortic stenosis
Describe Transcutaneous Aortic Valve Implantation (TAVI)
• Minimally invasive
• Pass catheter up the aorta then inflate balloon across the narrowed
valve which will crack the calcification
• Then pass another catheter which leaves a stent with a valve = new aortic valve
A 78 year old man presented with episodes of loss of consciousness on exertion. On examination, the carotid pulse is rising slowly. There is a loud ejection systolic murmur at the aortic area, radiating to both carotid arteries.
Presentation of what disease of heart valve
Aortic stenosis
What is aortic regurgitation
Leakage of blood into the left ventricle from aorta during diastole due to ineffective coaptation (bringing together) of the aortic cusps, of which there are three
Risk factors of aortic regurgitation
- SLE (ai disease)
- Marfan’s and Ehlers-Danlos syndrome (connective tissue disorders)
- Aortic dilatation
- Infective endocarditis or aortic dissection
Differential diagnosis of aortic regurgitation
- Heart failure
- Infective endocarditis
- Mitral regurgitation
Aortic regurgitation: What is Quincke’s sign
capillary pulsation in the nail beds
Aortic regurgitation: What is de Musset’s sign
head nodding with each heart beat
Aortic regurgitation: What is Pistol shot femoral
a sharp bang heard on auscultation
