12-15 lead ECG RBBB/LBBB

Question 1

What is a bundle branch block?

Answer 1

something that BLOCKS the normal conduction of the electrical activity of the heart!
- the impulse has to travel cell-to-cell rather than down the bundle branches!

Question 2

What do bundle branch blocks create to the QRS complex?

Answer 2

INCREASED QRS WIDTH ( >0.12s)

different morphologies of the complex!

Question 3

How do we diagnosis/ see a RBBB?

Answer 3

wide QRS complex
slurred s waves in lead I and V6
QRS pointing UP in V1

Question 4

What are causes of RBBB?

Answer 4

• right ventricular hypertrophy
• cor pulmonae (pulmonary hypertension)
• pulmonary embolism
• ischemic heart disease
• rheumatic heart disease
• myocarditis or cardiomyopathy
• degenerative disease of the conduction system
• congenital heart disease (atrial septal defect)

Question 5

What can we see on an ECG for LBBB?

Answer 5

wide QRS, pointing down in V1

Minimics STEMI (ST elevation and depression)

Question 6

What are causes are a LBBB?

Answer 6

hypertension
coronary artery disease
dilated cardiomyopathy
rheumatic heart disease

MOST are due to hypertension or CAD

Question 7

How do we diagnose LBBB?

Answer 7

wide QRS
LESS sharp in appearance than right
QRS pointing DOWN in v1

Question 8

A ventricular paced rhythm is a manmade ________

Answer 8

LBBB