Cardiology: Valvular Heart Disease: MS & MR Flashcards
What rhythm is shown in this CXR? [1]
Afib
What does this mitral valve ECHO show? [1]
Mitral regurg.
Why is the posterior mitral valve leaflet vulnerable to posterior MIs? [1]
posterior mitral valve leaflet is supplied by a branch of the RCA
Describe different causes of mitral regurgitation [++]
Mitral valve leaflet disease
- Mitral valve prolapse (leaflets prolapse during systole:
- Rheumatic disease
- Infective endocarditis: due to perforated leaflet; valve destruction
Subvalvar disease
- Chordal rupture (chordae tendinae)
- Papillary muscle dysfunction (usually ischaemic)
- Papillary muscle rupture
Functional MR
- Dilated Cardiomyopathy & LV dilatation
- Post MI: LV impairment & dilatation
Chronic atrial fibrillation leading to dilated left atrium & dilated annulus
Which chambers does the mitral valve sit between? [2]
What does each leaflet of mitral valve attach to? [1]
What do each of ^ attach to? [1]
Left atrium and ventricle
Leaflets attach to chordae tendinae
Chordae tendinae attach to papillary muscles, which attach to the ventricular wall
Describe the pathophysiology of acute MR [5]
Acute MR: fast and significant changes to flow without time for any adaptation or remodelling to occur:
- new regurgitation causes increased pressure within a non-compliant left atrium
- As result of the lack of compliance this is reflected in rises in pressure in the pulmonary circulation
- Ejection fraction falls as blood is ejected back across the regurgitant valve instead of forward though the aortic valve
- Tachycardia may occur to try and compensate
- Often fails and leads to cardiogenic shock
Describe the pathophysiology of chronic MR [2]
Chronic MR: Gradual worsening of regurgitation fraction that initally allows for compensation
- Compenstated state: left atria and ventricle dilate: LV undergoes eccentric hypertrophy and maintain a larger SV and therefore EF. The compliant and dilated left atrium prevents rises in pulmonary pressures
- Decompanstated state: eventually such changes cannot maintain normal cardiac function and the remodelling becomes increasingly pathological. The heart fails, ejection fraction falls and a backlog of blood waiting to be pumped through the left side of the heart occurs; pulmonary pressures rises and get congestive heart failure
What are the symptoms of MR? [4]
SOB & dysopnoea (to increase in left atrial pressure)
Fatigue
Signs of RHF (ankle swelling; distended abdomen)
Palpitations due to afib
Describe the signs of MR [6]
- Pan systolic, high pitched whistling murmur (due to high velocity of blood flow through the leaky valve)
- Murmur radiates to left axilla
- Soft S1: due to incomplete closure.
- 3rd heart sound may be present due to rapid filling of a dilated ventricle.
- Thrill on palpitation
- Signs of HF
- Signs of pulmonary oedema
- Afib
Which CT disorders can lead to MR? [2]
Ehlers-Danlos syndrome
Marfan syndrome
Which is the most associated with rheumatic fever?
Mitral regurgitation
Mitral stenosis
Atrial regurgitation
Atrial stenosis
Which is the most associated with rheumatic fever?
Mitral regurgitation
Mitral stenosis
Atrial regurgitation
Atrial stenosis
What is the investigation of choice for MR? [1]
ECHO
Allows visualisation of the incompetent valve and can confirm the underlying aetiology. Left atrial and ventricular enlargement may be seen in chronic MR.
What CXR findings would indicate MR? [2]
Left atrial and ventricular enlargement
Acute MR: pulmonary oedema (due to increased back pressure)
Dilated left atrium and left ventricle in a patient with chronic MR
What is a tell tale sign of left atrial enlargement? [1]
double-density sign, also known as the double right heart border
Normally the left atrium is located posteriorly and only the atrial appendage component is visible. **But left atria becomes englarged enlarged, the right aspect may become visible as an extra shadow next to the right atria **
If the double density sign is present on a CXR, what measurement can be taken to confirm left atrial enlargement? [1]
Olbique left atrial measurement: outer edge of atrium to midpoint of left main bronchus: > 7 cm = LA enlargement
Acute MR is characterised by which two features? [2]
Patients with acute MR are normally profoundly unwell. Condition characterised by shock and flash pulmonary oedema
Which drug can be used to reduce afterload before acute MR surgery? [3]
- diuretics
- sodium nitroprusside
- positive inotropes: dobutamine
- intra-aortic balloon counterpulsation (helpes the by heart indirectly by decreasing the afterload but increases cardiac output)
Which drugs would you give for MR patients in HF? [3]
- ACE inhibitors
- beta-blockers
- spironolactone
When is surgery indicated for chronic MR patients?
Chronic MR:
-
asymptomatic & LVEF < 60%
OR - asymptomatic & LV end systolic diameter >40mm
- All symptomatic if fit for surgery
BMJ BP
What surgical treatment is used to treat MR? [2]
Surgical valve repair
Valve replacement (artificial / pigs valve)
Explain why MR can occur after CAD or post-MI? [1
Following coronary artery disease or post-MI: if the papillary muscles or chordae tendinae are affected by a cardiac insult, mitral valve disease may ensue as a result of damage to its supporting structures.
Describe the aetiological causes of mitral stenosis [5]
- Rheumatic fever (most common)
- Congenital bicuspid aortic valve (BAV)
- Calcification
- LA thrombus causes mechanical compression of the valve
- SLE; RA; Carcinoid syndrome
Rheumatic fever is an immune-mediated inflammatory response to which pathogen?
Rheumatic fever is an immune-mediated inflammatory response to group A streptococcal pharyngitis
Molecular mimicry between streptococcal M protein and cardiac myosin leads to cross-reactive antibodies and T-cell responses, causing inflammation and damage to the mitral valve leaflets, chordae tendineae, and annulus.
Mitral stenosis causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
Mitral stenosis causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
Mitral stenosis causes left atrial hypertrophy
Aortic stenosis causes left ventricular hypertrophy
Mitral regurgitation causes left atrial dilatation
Aortic regurgitation causes left ventricular dilatation
Describe the symptoms of mitral stenosis [6]
- Mitral stenosis normally presents with exertional dyspnoea. Dysopnea due to left atrial pressure increasing causing pulmonary venous hypertension
- Haemoptysis due to pulmonary pressures and vascular congestion
- Malar flush
- Chest pain
- Atrial fibrillation is caused by the left atrium struggling to push blood through the stenotic valve causing strain, electrical disruption and resulting fibrillation.
- Signs of right ventricular failure - ankle swelling & distended abdomen: due to the development of pulmonary hypertension
Describe the signs of mitral stenosis [6]
- Mid-diastolic rumbling murmur: low velocity of blood flow (due to narrow area - rumbles way through). LENGTH OF RUMBLE CORRELATES TO THE INTENSITY
- Loud S1 caused by thick valves closing
- Tapping apex beat that is palpatable (due to loud S1)
- Atrial fibrillation: left atrium can’t push through stenotic valve - disrupts electrical signal
- RFH: Increase in JVP, basal creps, ankle oedema
Mitral regurgitation causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
Mitral regurgitation causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
atrial stenosis causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
atrial stenosis causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
atrial regurgitation causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
atrial regurgitation causes
left ventricular dilatation
left ventricular hypertrophy
left atrial dilatation
left atrial hypertrophy
Describe the pathophysiology of mitral stenosis [3]
Mitral stenosis results in raised left atrial pressures and atrial hypertrophy.
This predisposes to atrial fibrillation
Elevated left atrial pressure also causes pulmonary venous hypertension and subsequent pulmonary arterial hypertension resulting in right ventricular hypertrophy and dilation, ultimately progressing to right-sided heart failure
Explain why MS patients present with malar flush [1]
Malar flush refers to red discolouration of the skin over the upper cheeks and nose. It is due to the back pressure of blood into the pulmonary system, causing a rise in CO2 and vasodilation.
Patients with MS are at greatly increased risk of [] events.
Patients with MS are at greatly increased risk of thromboembolic events
Clots that develop in a dilated left atrium, often in the presence of atrial fibrillation, may throw off emboli into the systemic circulation.
What signs would indicate that MS has become more severe? [2]
length of murmur increases
opening snap becomes closer to S2
What medical therapy might be used to treat MS? [3]
- Diuretics alleviate pulmonary congestion and peripheral oedema
- Beta-blockers and anticoagulation (e.g., warfarin) manage atrial fibrillation
What are the non-medical interventions for MS? [2]
Percutaneous Balloon Valvuloplasty: procedure involves balloon dilation of the mitral valve to alleviate stenosis.
Surgical Intervention: valve repair; valve replacment
What valve area would indicate percutaneous balloon valvuloplasty? [1]
Severe mitral stenosis: valve area < 1.5 cm²
Describe the haemoptysis seen in MS [2]
range from pink frothy sputum to sudden haemorrhage secondary to rupture of thin-walled and dilated bronchial veins
Which form of ECHO is best for investigating mitral valve? [1]
transthoracic echocardiography
Mitral valve prolapse is associated with with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
Mitral valve prolapse is associated with with
Late systolic murmur
coarctation of aorta is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
coarctation of aorta is associated with
Late systolic murmur
aortic regurgitation is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
aortic regurgitation is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
mitral stenosis is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
mitral stenosis is associated with
Mid-late diastolic murmur, rumbling
patent ductus arteriosus is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
Continous machinery murmur
mitral regurgitation is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
Holosystolic murmur, harsh in character
hypertrophic obstructive cardiomyopathy
is associated with
Early diastolic murmur, high pitched and blowing
Holosystolic murmur, harsh in character
Continous machinery murmur
Ejection systolic murmur
Mid-late diastolic murmur, rumbling
Late systolic murmur
Mitral regurgitation is associated with
Ejection systolic murmur
