Overview Mitral regurgitation (MR), which is also known as mitral insufficiency, is a common heart valve disorder. When MR is present, blood leaks backwards through the mitral valve when the heart contracts. This reduces the amount of blood that is pumped out to the body. Patients with acute mitral regurgitation (MR) are often gravely ill with significant haemodynamic abnormalities that require urgent medical and usually surgical treatment
Think MR can be acute (pulmonary oedema), chronic compensated or chronic decompensated |
The heart has 4 valves:
The Mitral and tricuspid valves are atrioventricular valves meaning they allow blood to move from the atrium to the ventricles of the heart. This occurs with ventricular diastole.
The aortic and pulmonary valve are tricuspid valves which when open allow blood to move to the aorta and pulmonary system respectively. This occurs during ventricular systole when the heart contracts.
Surface anatomy of the heart valves
All of the heart valves except the mitral valve are usually tricuspid. However, there can be congenital bicuspid valves which can predispose one to valvular disease later on. The heart valves can be heard most prominent in the following regions of the chest
Risk Factors |
Mitral valve prolapse |
History of rheumatic heart disease |
Infective endocarditis |
History of cardiac trauma |
History of ischemic heart disease/ MI |
Congenital heart disease |
Hypertrophic cardiomyopathy |
Anorectic/dopaminergic drugs |
Acute MR presents as a cardiac emergency, however chronic MR typically presents with no symptoms until late stage.
Remember Acute Mitral Regurgitation presents with Left sided heart failure |
Cardiac Examination
Cardiac Examination includes a murmur heard over the left 5th intercostal space mid-clavicular. The murmurs is a flat continuous murmur which radiates to the axilla. There also tends to be a diminished S1.
Clinical Signs of severity
Think Breathing out as if you were straining (vasalva manoevre) increases intrathoracic pressure -> decreases venous return and accentuates murmur from mitral valve prolapse and hypertrophic obstructive cardiomyopathy |
Diagnosis
Clinical history and examination findings of MR. Ultrasound finding of mitral valve insufficiency.
There are three basic mechanisms of Mitral regurgitation:
Side Note Another way of thinking about aetiology. Primary causes include abnormality of dysfunction of any component of the mitral valve apparatus. Secondary causes (functional MR) abnormality of dysfunction of the left ventricle |
Primary causes abnormality of dysfunction of any component of the mitral valve apparatus
Secondary causes (functional MR) abnormality of dysfunction of the left ventricle
Pathophysiology Acute MR
Pathophysiology Chronic MR
Acute Mitral Regurgitation
Inoperable patients
Operable patients
Chronic Mitral Regurgitation
Remember If in AF, anticoagulate with warfarin (however now NOACs are being more frequently used) |
Complication
Overview Most common congenital valvular lesion. Associated with Marfan’s Syndrome and Ehlor's Danlos Syndrome.
Clinical Examination
Remember Mitral valve prolapse has a systolic click where as regurgitation does not! |
Complications
Side note Leg raise and squatting increasing blood flow back to the heart. Valsalva decrease blood to the heart. |
Remember only Mitral valve prolapse and HOCM murmus increase with murmurs. |