Case 1

80 year old female

Past medical hx : hyperlipidemia, diabetes
Chief complaint : giddiness and breathless for 2 days
BP 100/60, HR 40

(1) What is the diagnosis?
(2) How would you manage this patient?


Answer : Complete (Third Degree) Heart Block

• Complete dissociation of P waves with QRS complexes
• P-P interval regular; R-R interval also regular

Causes

• Myocardial infarction - in 10% of inferior MI (usually benign); more serious if associated with anterior MI
• Cardiomyopathy (e.g. Lyme disease), acute rheumatic fever
• Overdose of meds (e.g. calcium-channel blocker; beta-blockers)
  

Approach

• Manage as P1 case
• Immediate support of ABC and cardiac monitoring

1. High-flow oxygen
2. IV access - take blood for FBC/ UE/ cardiac enzymes & troponin

• Atropine - 0.6 mg IV every 5 mins up to total of 3 mg
• Consider dopamine
• Transcutaneous pacing if medications ineffective (with analgesia/ sedation)
• Transvenous pacing (by cardiologist) if transcutaneous pacing unsuccessful, or as a definitive procedure after stabilized with transcutaneous pacing
  
• Treat underlying cause (e.g. MI, overdose) and complications (heart failure, shock)