5. Causes
• MR also seen in diseases of the
myocardium (dialated and hypertrophic
cardiomyopathy),
• Rheumatic autoimmune diseases
• Eg: SLE
• Collagen diseases
• Eg: Marfan’s syndrome
• Ehlers –Danlos syndrome
• Drugs inducing centrally acting appetite
suppressants, and dopamine agonists
JMJ 5
6. Pathophysiology
• Due to regurgitation into L atrium
– L/ atrium dilates
– Little increase in left atrial pressure if the
regurgitation is long standing
• In acute MR
– L/ atriam does not dilate
– So pressure inside it increases
JMJ 6
7. Pathophysiology
• Thus in acute MR
– Left arterial v-wave is greatly increased
– Pulmonary venous pressure rises to produce
pulmonary edema
• Proportion of the stroke volume
regurgitate
• Stroke volume increases to maintain CO
• So Left ventricle enlarges
JMJ 7
11. Symptoms
• Increased SV
– symptoms of R/ heart failure
– Eventually leads to congestive cardiac failure
• Cardiac cachexia may developed
• Thromboembolism is less common
• Sub-acute infective endocarditis is much
more commoner
JMJ 11
14. Signs of uncomplicated MR
• Laterally displaced diffuse apex beat and a
systolic thrill
• Soft 1st heart sound
• Pansystolic murmur
– Loudest at apex
– Radiating widely over the precordium & into
the axilla
• With a floppy mitral valve : there may be a
mild systolic click
• Prominent 3rd heart
JMJ 14
16. Investigation – X-ray
• Left atrial, Left ventricular
enlargement
• Increase in CTR, and valve calcification
is seen
JMJ 16
17. Investigation – ECG
• Features of
– left atrial delay (bifid P wave)
– Left ventricular hypertrophy
• Tall R waves in left lateral leads (I & V6)
• Deep S wave in R sided precordial area ( V1, V2)
JMJ 17
19. Investigation – Echocardiogram
• Dilate left atrium and left ventricle
• May be specific features of chordal or
papillary muscle rupture
• TOE can be done
JMJ 19
20. Treatment
• Prophylaxis against endocarditis
• Any evedence of progressive cardiac
enlargement surgical
– Mitral valve repair
– Mitral valve replacement
JMJ 20
21. Prolapsing (Billowing) mitral valve
• Barlow’s syndrome/ floppy mitral valve
• Due to excessively large mitral valve
leaflets,enlarged mitral annulus
• More common in young females
• Cause is unknown but associate with
Marfan’s syndrome, thyrotoxicosis,
rheumatic or ischemic heart disease
JMJ 21