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Question 1

Mitral Stenosis

Question 2

Mitral Regurg

Answer 2

Causes
* Primary = Degenerative disease (MR prolapse), Rheumatic Fever, IE
* Secondary (functional) = LV dysfunction caused by coronary heart disease or dilated cardiomyopathy

Acute MR = Sx of Acute HF (e.g. pulmonary oedema)
Chronic MR = Initial compensation via cardiac remodelling, then eventually

Question 3

Aortic Stenosis

Answer 3

Signs:
* Crescendo-Decrescendo Ejection Systolic Murmur
* ?Radiates to carotids
* Pulsus parvus et tardus (small and late) - Carotid pulse peaks closer to S2 (normally closer to S1) and is weak
* Narrow pulse pressure (i.e. difference between SBP and DBP <30 due to reduced stroke volume)
* S4

Symptoms
* Chest pain
* SOB
* Syncope/Pre-syncope

Causes
* Valve sclerosis - calcification + fibrosis (Most common cause overall, >65yo)
* Bicuspid aortic valve (<65yo)

Classification
* AHA/ACC Classification
* Divided into mild-moderate and severe AS
* Based on AVA (Aortic valve area) and Mean Aortic Pressure Gradient
* AVA ≤1cm2 = SEVERE AS
* Aortic Pressure Gradient ≥40mmHg = SEVERE AS

Diagnosis
* Transthoracic Echo = Gold standard
* ECG - signs of LV Hypertrophy (concentric)
* CXR - pulmonary oedema (LHF), signs of LV Hypertrophy, sometimes visible calcification of aortic valve
* Cardiac catheterization - only if other Ix inconclusive

Management
* Symptomatic or Severe AS = Valve replacement
* Otherwise = conservative (Serial Echos, manage co-morbidities, IE prophylaxis)

Valve replacement types
* Surgical - <65yo, >20yrs Life expectancy
* Transcatheter - >80yo, <10yrs Life expectancy
* Percutaneous Balloon Valvuloplasty - children & young adults

Complications of AS
* Cardiogenic shock
* Acute HF
* Fast AF

Question 4

Aortic Regurg

Answer 4

Acute & Chronic causes

Sudden, severe SOB
Rapid

Question 5

Valve replacement

Answer 5

Indications:
* Symptomatic + Severe AS
* Asymptomatic AS with valvular gradient >40

Types of surgery
* Surgical AVR = young, low/medium risk pts
* Transcatheter AVR = high risk pts

Question 6

Permanent Pacemaker (PPM)

Answer 6

• Consist of a pulse generator (metal bit) implanted superficial to pectoralis muscle in infraclavicular region - and also transvenous leads which are attached to the myocardium.
• Leads go inserted via subclavian/cephalic/axillary vein
• Single chamber = R ventricle
• Dual chamber = R ventricle + R atrium

Indications for Permanent Pacemaker:
* Second degree Mobitz type 2
* Complete Heart block
* Symptomatic bradycardias (Sick sinus syndrome)

Indications for Temporary Pacemaker
* Haemodynamically unstable brady
* Prophylactically after cardiac surgery

Single chamber indications
* Permanent AF (single lead in RV)

Complications of pacemaker?
* Infection
* Pneumothorax
* Thromboembolism

How long does pacemaker battery last?
5 - 10 years

Question 7

Implantable Cardioverter Defibrillator (ICD)

Answer 7

Function = To monitor rhythm + deliver electrical shocks to myocardium

Transvenous = Defib + Synchronised cardioversion
Subcutaneous = Defib ONLY

Indications: Generally to prevent death from ventricular tachyarrhythmias

Primary prevention = Select patients w/ >1yr expected survival and:
* HOCM, Inherited channelopathies (Congenital Long-QT syndrome, Brugada syndrome), Severe congestive HF

Secondary prevention = ALL patients w/ >1yr expected survival + an irreversible cause of ventricular tachyarrhythmias and:
* Sudden cardiac arrest
* Unstable VT, Stable sustained VT

Question 8

Cardiac Resynchronisation Therapy (CRT)

Answer 8

BIVENTRICULAR pacing (cardiac resychronisation)
Improves outcomes in Congestive HF

Also has Anti-bradycardia pacing

Indications:
Congestive HF - usually LVEF ≤35% + Wide QRS complex