Mitral valve stenosis (Complete)

Question 1

What are the main causes of mitral valve stenosis?

Answer 1

Rheumatic heart disease (MOST COMMON)

Mitral anular calcification

Congenital mitral stenosis

Mucopolysaccharidosis

Carcinoid syndrome

Systemic diseases: SLE, Rheumatoid arthritis

Question 2

Rheumatic fever is caused by what pathogen?

Answer 2

Streptococcus pyogenes

N.B. Patient presents with strep throat, may present with fever 2-4 weeks later.

Damage to valve occurs due to triggering of abnormal autoimmune response

Question 3

What are main signs/symptoms of mitral valve stenosis?

Answer 3

Symptoms:

Dyspnoea

Haemoptysis

Hoarseness (if left atrium compresses recurent laryngeal nerve)

Signs:

Mid/end-diastolic murmur heard loudest during expiration

Loud S1

Opening snap

Malar flush

Low volume pulse

Atrial fibrilation

Signs of HF

Parasternal heave (Right ventricle hypertrophy)

Peripheral oedema and hepatomegaly (RHF)

Question 4

How does haemoptysis typically present in patients with mitral stenosis?

Answer 4

Pink frothy sputum

Sudden haemorrhage sputum: Secondary to rupture of bronchial veins

Question 5

What does opening snap sound in mitral stenosis indicate?

Answer 5

Indicated mitral valve leaflets are mobile

Question 6

Why can mitral stenosis cause AF?

Answer 6

Raised atrial pressure causes hypertrophy which leads to AF

Question 7

What are signs of severe mitral stenosis?

Answer 7

Prolonged murmur

Opening snap occurs closer to S2

Question 8

Why can mitral stenosis cause hoarseness in some cases?

Answer 8

Left atrium hypertrophy can compress recurrent laryngeal nerve

Question 9

What investigations should be considered in patients with mitral valve stenosis?

Answer 9

Bedside:

ECG: P-mitrale, RHF, AF

Imaging:

CXR: Pulmonary oedema and left atrial enlargement

ECHO

Cardiac MRI: Show valvular vegetations

Question 10

What ECG findings can be seen in mitral vave stenosis?

Answer 10

P-mitrale (a broad notched P wave due to left atrial enlargement)

Right ventricular hypertrophy

Right axis deviation

Atrial fibrillation - caused by left atrial enlargement

Question 11

What imaging is diagnostic for mitral stenosis?

Answer 11

ECHO

Question 12

What findings on ECHO suggest mitral stenosis?

Answer 12

Mitral valve cross section <4 sq cm

Question 13

What is the management plan for mitral valve stenosis in assymptomatic patients?

Answer 13

Regular ECHO monitoring

This is due to risk of pulmonary hypertension and RHF if untreated

Question 14

What is the management plan for mitral valve stenosis in symptomatic patients?

Answer 14

Surgical:
Percutaneous mitral balloon valvuloplasty

Mitral valve surgery (commissurotomy, or valve replacement)

Medicine:

Warfarin: Patients with AF and severe/moderate stenosis

Management of heart failure

Question 15

Percutaneous balloon valvuloplasty should be considered in which patients?

N.B. valvuloplasty is same as valvotomy

Answer 15

Symptomatic patients with severe MS (<1.5) but valve is pliable and non-calcified (favourable valve morphology)

Question 16

When is mitral valve repair or replacement surgery considered?

Answer 16

Either of following:

Severe symptomatic MS not amenable to valvuloplasty

Left arterial thrombus

Significant mitral regurgitation

N.B. Typically metal vs bioprosthetic

Question 17

Patients with metallic mitral valve should be anticoagulated with?

Answer 17

Warfarin

Target INR 2.5-3.5

Question 18

Why does mechanical mitral valves have a higher INR range than aortic mechanical valves?

Answer 18

Due to more haemodynamic stasis around the mitral region physiologically