Valve Disease

Question 1

What are the main causes of AS?

Answer 1

Calcific trileaflet disease (progresses more rapidly in those with pagets or renal impairment)
Congenital (bicuspid 0.5-1.4%, unicuspid)
Rheumatic
Rare -fabrys, SLE

Question 2

Why do patients with AS get angina?

Answer 2

1/2 have underlying CAD
Otherwise due to increased myocardial O2 demand by hypertrophied ventricle, compression of intramyocardial coronary arteries and reduce diastolic coronary perfusion

Question 3

What is the ECHO criteria for severe AS

Answer 3

Aortic valve area (AVA) - less then 1cm2
Aortic jet velocity - greater then 4m2
Mean pressure gradient - greater then 40mmhg
Velocity ratio - less then 0.25

Question 4

What is meant by pseudo stenosis in AS

Answer 4

Some have low transvalvular pressure gradient due to the combination of moderate AS and low cardiac output
Need to do Dobutamine stress ECHO to accurately quantify severity of valve disease

Question 5

When would you treadmill patients with AS

Answer 5

In severe as symptomatic patients

- if develop symptoms at low workload or drop BP would reach threshold for surgery

Question 6

What are the indications for balloon valvuloplasty in AS

Answer 6

• Can be used as a bridge to surgery in haemodynamically unstable patients
• Palliation
• symptomatic pregnant women
• those needing to go for urgent non cardiac surgery

All above in those with sever symptomatic AS

Question 7

What are some complications with balloon valvuloplasty

Answer 7

Stroke, severe AR, MI
Re-stenosis and clinical deterioration occur in 6-12 months in most cases

Complication rate 10-20%

Question 8

When would you consider TAVI for AS

Answer 8

In those with an indication for valve replacement that have too high surgical risk
Need life expectancy greater then 12 months

Question 9

Indications for surgical management of AS

Answer 9

• severe AS with symptoms (including those with Symptoms on ETT)
• asymptomatic, severe AS + LVEF less than 50%
• severe AS undergoing other cardiac surgery
• very severe AS, asymptomatic, low surgical risk
• severe, aymptomatic AS with bicuspid valve and dilated aortic root greater then 4.5cm

Question 10

What two factors determine choice of prosthetic valve?

Answer 10

Age - under 60 (consider also 60-70) mechanical valve due to longer duration
Anticoagulation - if intolerant/adherence or contraindications to long term oral anticoagulation choose bioprosthetic valve

Question 11

What are the two categories of causes of AR and some examples?

Answer 11

Primary valve problem - rheumatic, congenital bicuspid, infective endocarditis, ank spon, trauma
Primary aortic root - marfans, osteogenesis imperfecta, other connective tissue diseases, severe HTN, dissection, syphilis, ank spon

Question 12

What are the physiological changes in AR

Answer 12

Blood flows from aorta into LV in diastole - increased end diastolic volume - ventricle dilates and hypertrophies to maintain SV - eventually get LV failure

Question 13

ECHO criteria for severe AR

Answer 13

Regurgitant volume greater than 60mls per beat
Regurgitant fraction greater then 50 %
Diastolic flow reversal in aorta
Vena contracta (greatest diameter of regurgitate jet) greater then 6mm
Effective regurgitation oriface greater then 0.3cm2

Question 14

What are the time frames for surveillance for AS

Answer 14

Mild AS - 3-5 years
Moderate - 1-2 years
Severe - 6-12months (earlier if symptoms develop)

Question 15

Indications for AVR in chronic severe AR

Answer 15

• symptomatic (or symptoms on ETT)
• asymptomatic with EF less than 50%
• asymptomatic requiring other cardiac surgery
• asymptomatic with LV diastolic dimension greater then 75mm or systolic dimension greater then 55mm

Question 16

What are the 3 main symptoms of AS and corresponding survivals after the onset of each symptom?

Answer 16

Angina -3 years from onset
Syncope - 2 years
Dysnoea - 1 year

Question 17

What drugs should you avoid in AR?

Answer 17

Drugs that increase the duration of diastole as this increases the time for regurgitation (ie b-blockers)

Question 18

What are the causes of MS?

Answer 18

Almost all rheumatic (estimated 99%, but only 50-70% have a history of infection)
Infective endocarditis
Mitral annular calcification
Congenital
SLE
Carcinoid heart disease (particularly in presence of PFO)

Question 19

What are symptoms of MS?

Answer 19

Dysnoea - slowly progressive
Haemoptysis - due to pul HTN
Atrial fibrillation
Thromboembolism (80% of those that present with thromboembolism have AF)
Symptom of right sided HF
Hoarse voice

Question 20

What is the measurement used to classify MS severity? What are the classes?

Answer 20

Valve area
Mild - AVA greater then 1.5cm2
Moderate - 1-1.5
Severe - less then 1.0

Question 21

Medical management of MS?

Answer 21

Vaccinations
Secondary prevention of rheumatic fever
Anti thrombotic therapy in AF or atrial thrombus (warfarin only, dabigatran not proven)
In times of decompensation due to illness/pregnancy - diuretics/b-blockers
Rate control of AF

Question 22

What are the two options for repair of mitral valve and what is the preferred option in most cases?

Answer 22

Mitral valve repair (preferred in most cases, lower mortality rates and similar rates of re-operation)
Vs mitral valve replacement