Mitral valve defects

Question 1

Describe the mitral valve?

Answer 1

It has two leaflets only, anterior that cover most of the opening and posterior leaflet, typically it is 4-6 cm2 in area, anterior cusp is bigger, it resembles mitre, it is valve between left atrium and ventricle

Question 2

What is mitral stenosis?

Answer 2

Narrowing of the mitral valve, it does not open fully

Question 3

What are possible causes of mitral stenosis?

Answer 3

Rheumatic heart disease, systematic conditions such as systemic lupus erythematosus, rheumatoid arthritis

Question 4

What is the reduction of the orificle size in mitral stenosis ?

Answer 4

From 4-6 cm2 to about 2 cm2

Question 5

What is the outcome of the mitral stenosis?

Answer 5

Increased pressure in LA, pulmonary venous and capillary pressure is increased, this leads to pulmonary hypertension, due to hypertension the right side of the heart enlarges, there is tricuspid and pulmonary regurgitation, but LV functions normally

Question 6

What happens to the left side of the heart in mitral stenosis?

Answer 6

There altered trans-valvular gradient and also flow rate, the CO is reduced, this can leads to tachycardia especially on exercise, acute illness, pregnancy

Question 7

What are the symptoms of mitral stenosis?

Answer 7

Dyspnoea on exertion due to pulmonary oedema, haemoptysis as small blood vessels can rupture, chest pain, hoarseness of voice due to compression of the left recurrent laryngeal nerve, fatigue, palpitations

Question 8

What are the signs of mitral stenosis?

Answer 8

mitral facies (red discolouration of cheeks, nose, rest of face has bluish tinge), low volume pulse, JVP prominent a wave, tapping apex beat and diastolic thrill, RV heave, diastolic decrescendo murmur, common AF

Question 9

What investigations are needed for mitral stenosis?

Answer 9

ECG, echo, cardiac catheterisation, chest X ray, MRI

Question 10

What can be observed in ECG?

Answer 10

prolonged P wave

Question 11

What can be observed on chest X ray?

Answer 11

Enlarged LA

Question 12

What is the treatment for mitral stenosis?

Answer 12

salt restriction, diuretics, anticoagulation and arrhythmic control if AF, valvotomy, mitral valve repair or replacement

Question 13

What are complications of mitral stenosis?

Answer 13

Pulmonary hypertension, hoarseness, dysphagia, bronchial obstruction, IE, emboli

Question 14

What is mitral regurgitation?

Answer 14

When the mitral valve becomes leaky

Question 15

What are the causes of mitral regurgitation?

Answer 15

Rheumatic heart disease, degenerative causes, infective endocarditis, due to ventricle dilation

Question 16

Describe the effective regurgitant orificle

Answer 16

It is not fixed, it depends on preload, after load, contractility

Question 17

What is the difference between acute and chronic?

Answer 17

Acute presentation is an emergency, the ventricles do not have time to adapt, end systolic pressure and volume decreases, in chronic presentation ventricles have time adapt, they increase contractility to compensate, they also dilate to accommodate more blood

Question 18

Describe the changes that occur in the left atrium in mitral regurgitation

Answer 18

LA has small compliance, pressure rise, thickening of the wall of myocardium, remodelling of pulmonary vasculature, pulmonary hypertension, can also develop fibrillation

Question 19

Describe acute presentation of mitral regurgitation

Answer 19

Due to valve perforation, chrodea or papillary muscle prolapse, symtoms are breathlessness, cardiogenic shock

Question 20

Describe chronic presentation of mitral regurgitation

Answer 20

fatigue, right heart failure, dyspnoea, palpitations due to AF, ventricles start failing especially on exertion, history from patients

Question 21

Describe the signs of mitral regurgitation

Answer 21

normal or reduced pulse, JVP is prominent, hyper dynamic apex beat, RV heave, systolic murmur that is loud and can obscure the heart sounds, pan systolic murmur that radiates to the axilla

Question 22

What are the investigations for mitral regurgitation?

Answer 22

ECG (bigger and longer P wave), chest X ray (LA and LV enlargement), echo, cardiac catherisation, cardiac catheterisation, cardiac MRI

Question 23

What is the treatment for mitral regurgitation?

Answer 23

acute sodium nitropresside, dobutamine, chronic diuretics, valve repair or replacement