Arrhythmias

Question 1

What are the typical symptoms on presentation in a patient with arrhythmias? What other points are important to elicit on history?

Answer 1

• Palpitations (missed beats, flutter, racing/strong beat)
• Tiredness
• Dizziness
• Syncope
• Signs of CCF (e.g. mild dyspnoea)
• CV risk factors, EtOH, caffeine intake, stress

Question 2

What signs are important to look for on examination in a patient with suspected arrhythmia?

Answer 2

Heart rate - speed and rhythm

Signs of CCF (ventricular arrhythmias)

Signs of thyrotoxicosis

Question 3

What is the investigation trail for working up arrhythmias?

Answer 3

ECG

Holter monitor

Echocardiogram

Question 4

What are the principles of managing AF?

Answer 4

Rate control or rhythm control

• Rate control preferred, especially after 48 hours
  
  • Beta-blockers, diltiazem
  • Digoxin, amiodarone if CCF present
• Cardioversion
  
  • If unstable - DCR

Anticoagulation

• IV heparin pre-cardioversion
• NOACs/warfarin

Question 5

Most supraventricular tachycardias are …. tachycardias

Answer 5

AV nodal re-entry (60%)

AV re-entrant tachycardias (30%) e.g. WPW syndrome

Question 6

The ECG characteristic of a supraventricular tachycardia is?

Answer 6

Regular, narrow QRS complex

Question 7

The management principles in supraventricular tachycardias (non-AF) are?

Answer 7

• Unstable patient?
  
  • DCR
• Short term rate regulation
  
  • Vagal manouvres
  • Adenosine (blocks AV node)
• Long term rate regulation
  
  • Beta-blockers, CCBs
  • Ablation of aberrant pathways

Question 8

The ECG characteristic of a ventricular tachycardia is?

What other arrhythmias can cause this ECG appearance?

Answer 8

Regular, broad complex tachycardia

Also seen in SVTs with LBBB and patients with WPW syndrome

Question 9

What are the risk factors for ventricular tachycardias

Answer 9

• CAD/IHD
• Hypertrophic cardiomyopathy
• LV systolic dysfunction
• Long QT
• Brugada
• Hypokalaemia/hypomagnesaemia

Question 10

What are the management prinicples for ventricular tachycardias?

Answer 10

• Haemodynamically unstable or torsades de points?
  
  • DCR, amiodarone (300 mg), with correct of any electrolyte abnormalities
• Haemodynamically stable
  
  • Amiodarone with subsequent DCR if unsuccessful
• Post-cardioversion
  
  • Treatment of underlying cause e.g. aberrant pathways, consider ICD
  • If idiopathic - B-blockers, CCBs, catheter ablation