Mitral regurgitation

Question 1

What is the definition of mitral regurgitation?

Answer 1

Reversal of blood flow from LV to LA

Question 2

What is the aetiology of mitral regurgitation?

Answer 2

Structural:
Ischaemic heart disease
Degenerative 
Mitral valve prolapse 
Functional mitral regurg (occurs when valve dilates)

Infective:
Rheumatic heart disease
Infective endocarditis

Question 3

What is the pathophysiology behind mitral regurgitation?

Answer 3

Dilation:
Chronic eventually leads to dilation of the LA with little increase in pressure + few symptoms so regurg vol increases. Once limit reached, will cause heart failure

LV compensation:
Acute- cant compensate so endsystolic pressure and volume will decrease

Chronic: increase in endsystolic pressure due to compensation of dilation and endsystolic V returns normal. But instead develop eccentric LV hypertrophy

LA compliance:
Reduced in both chronic/acute-
due to pressure rice and thickening of myocardium. Increased Pulmonary ressitance and hypertension

Increased in both again due to volume enlargment (low blood perfusion) and lesser changes in pulm vasculature

Peripheral oedema:
due to decreased SV through aorta so decrease CO and BP and organ perfusion so theremore activate RAAS and increase absorption of water in kidney and causes peripheral oedma

Question 4

Name acute symptoms

Answer 4

Sudden breathlessness and cardiogenic shock

Question 5

Name the chronic symptoms

Answer 5

Asymptomatic initally 
Breathlessness and orthopnoea 
Chest pain 
Fatigue due to low O2
Palpitations due to increased SV and Afib
Right heart failure

Question 6

What are 4 signs?

Answer 6

Pulse is normal
JVP= prominant if RH failure
Brisk and Hyperdynamic apex beat
RV heave

Question 7

What is the auscultation sounds?

Answer 7

Reduced S1
Split S2 - early A2 and loud P2

Holosystolic, blowing and loud and displaced apex

Burrrrrrrr

Pansystolic high pitch

Question 8

What is the investigation?

Answer 8

ECG

• Atrial fibrillation
• LA enlargement (p wave more than 0.12s and the waves are broad
• RV hypertrophy ( prominant R wave)

CXR:

• Any hypertrophy
• Calcification of mitral annulus
• Cardiomegally

Echocardiograph
-LV dimensions
-DiIlation of LA/LV
based on seeing leaflet dysfunction,chordae,pap muscle and annular disease

Question 9

What are the treatments?

Answer 9

Mainly managing the atrial fibrillation and the hypertension

For acute: 
Preload and afterload reduction can be lifesaving by: 
dobutamine
nitroprusside
IABP

Chronic:

Lack of evidence for haemodynamic improvement