Implantable Devices

Question 1

Implantable devices

Answer 1

This patient has had syncope. Please examine his cardiovascular system.

Question 2

Clinical signs of Implantable Device

Answer 2

1. Incisional scar in the infraclavicular position (may be abdominal)
2. Palpation demonstrates a pacemaker
3. Signs of heart failure: raised JVP, bibasal crackles and pedal oedema
4. Medic alert bracelet
5. Local infection: red/hot/tender/fluctuant/erosion

Question 3

Implantable cardiac defibrillators (ICD)

Answer 3

‘Shock box’ also delivers anti‐tachycardia pacing (ATP) – improves mortality

Question 4

Indications of ICD as a Primary prevention

Answer 4

1. MI > 4 weeks ago (NYHA no worse than class III)
   ⚬⚬ LVEF < 35% and non‐sustained VT and positive EP study or
   ⚬⚬ LVEF < 30% and QRSd ≥ 120 milliseconds
2. Familial condition with high‐risk SCD ⚬⚬ LQTS, ARVD, Brugada, HCM, complex congenital heart disease

Question 5

ICD for Secondary prevention (without other treatable cause)

Answer 5

1. cardiac arrest due to VT or VF or
2. Haemodynamically compromising VT or
3. VT with LVEF < 35% (not NYHA IV)

Question 6

Cardiac resynchronization therapy (CRT ) – biventricular pacemakers (BiV)

Answer 6

Extra LV pacemaker lead via the coronary sinus – improves mortality/symptoms. May be considered if:

1. LVEF < 35%
2. NYHA II–IV on optimal medical therapy
3. Sinus rhythm and QRSd > 150 milliseconds (if LBBB morphology may be >120 milliseconds)

Question 7

New York Heart Association (NYHA) functional classification of heart failure.

Answer 7

I = Cardiac disease, but no symptoms and no limitation in ordinary physical activity, e.g. no shortness of breath when walking > 300 m, climbing stairs etc.

II = Mild symptoms (mild shortness of breath and/or angina) and slight limitation during ordinary activity 100-300 m.

III = Marked limitation in activity due to symptoms, even during less-than-ordinary activity, e.g. walking short distances (20–100 m). Comfortable only at rest.

IV = Severe limitations. Experiences symptoms even while at rest. Mostly bed-bound patients.