ECG

Question 1

AV block: 1st degree

Answer 1

-Elongated PR interval (> 0.2 s = 1 big box-5 little boxes)

Sx: Dizziness, syncope

Question 2

AV block: 2nd degree block

Answer 2

• Wenckebach (“longer, longer, longer, drops, that is a wenkebach”) or Mobitz I: At the AV node
  - PR becomes longer and longer- then a missing QRS complex (cycle/series)
• Mobitz II: below the AV node
  - PR is OK (no prolongation) -then missing QRS complex
  - Sometimes QRS is wide
  - Pacemaker

Question 3

AV block: 3rd degree

Answer 3

• P-P and R-R are constant intervals
• Sometimes p waves are buried under the QRS complex

Bradycardia, dizziness, and syncope

Question 4

BBB Block

Answer 4

1. Rate: Depends
2. Rhythm: Regular
3. P wave: Normal
4. PR interval: Normal
5. QRS: Wide

Question 5

Right BBB Block

Answer 5

Causes:

• Coronary artery disease
• Anterior wall MI
• HTA
• Scar tissue (from trauma or surgery, myocarditis, pulmonary embolism)
• Drug toxicity
• Congenital heart defects

Question 6

Left BBB Block

Answer 6

Causes:

• Anterior Wall MI
• Aortic stenosis
• Degenerative changes
• Cardiomyopathy