Conditions associated with sudden cardiac death

Question 1

Long QT Syndrome - symptoms

Answer 1

• Syncope
• Exercise induced syncope
• Often people don’t know they have this condition until they

Question 2

Long QT Syndrome - causes

Answer 2

• It is often inherited: genetic cardiac ion channel mutation (Na+, K+)
• Drugs: amiodarone, TCA’s, many antibiotics, fluconazole, erythromycin, metoclopramide, quinidine, haloperidol, droperidol, methadone, ondansetron, SSRI’s
• Myocardial disease: MI, RF (rheumatic fever) , 3rd degree HB, cardiomyopathy
• Electrolytes: low Ca2+, low K+, low Mg2+

Question 3

Long QT Syndrome - ECG features

Answer 3

• QTc duration of >440 in men
• QTc duration of >460 in women

Question 4

Brugada Syndrome - symptoms

Answer 4

• Two-thirds of people are asymptomatic
• Syncope
• Unexplained cardiac arrest (usually during sleep or rest)
• Nocturnal agonal respirations

Question 5

Brugada Syndrome - causes

Answer 5

• Autosomal-dominant inherited cardiac sodium channelopathy
• More common in males
• More common in people of Southeast Asian descent

Question 6

Brugada Syndrome - ECG features

Answer 6

There are three ECG findings associated with Brugada:
- Type 1 (diagnostic) with coved-type ST elevation of >2mm and negative T waves in V1-V3 (along with at least one of the clinical criteria)
- Type 2 with saddle-back ST elevation of >2mm and positive or biphasic T wave
- Type 3 with morphology of either type 1 or type 2 but with <2mm of ST elivation
- Atrial fibrillation / flutter may also be present

Question 7

Brugada syndrome - clinical criteria

Answer 7

• Documented polymorphic VT or VF
• Family history of sudden cardiac death at <45 years old
• Coved-type ECGs in family members
• Inducibility of VT with programmed electrical stimulation
• Syncope
• Nocturnal agonal respiration

Question 8

Hypertrophic Cardiomyopathy (HCM) - symptoms

Answer 8

• Dyspnoea
• Syncope/presyncope
• Chest pain
• Angina
• Palpitations
• Symptoms of HF: orthopnoea, paroxysmal nocturnal dyspnoea
• Sudden cardiac death

Question 9

Hypertrophic Cardiomyopathy (HCM) - causes

Answer 9

Genetic condition affecting sarcomeric proteins causing left ventricular wall thickness - not explained by abnormal loading conditions

Question 10

Hypertrophic Cardiomyopathy (HCM) - ECG features

Answer 10

• Left ventricular hypertrophy (voltage + non-voltage) criteria
• Deep anterior lateral T wave inversions
• Dagger like Q waves in inferior lateral leads
  (Inferior lateral leads - II, III, aVF, V5 and V6)

Question 11

Arrhythmogenic Right Ventricular Cardiomyopathy / Dysplasia (ARVC/D) - symptoms

Question 12

Arrhythmogenic Right Ventricular Cardiomyopathy / Dysplasia (ARVC/D) - ECG features

Question 13

Dilated Cardiomyopathy - symptoms

Question 14

Dilated Cardiomyopathy - ECG features

Question 15

Wolf-Parkinson White Syndrome - symptoms

Question 16

Wolf-Parkinson White Syndrome - ECG features

Question 17

Myocarditis - symptoms