Bundle Branch Blocks and Related Abnormalities

Question 1

Characteristics of Right Bundle Branch Block (RBBB) ?

Answer 1

rSR’ complex in lead V1 with a wide R’ wave, qRS pattern in lead V6 with a wide S wave, T wave inversions and slight-moderate ST depressions also may be seen

Question 2

Characteristics of Left Bundle Branch Block (LBBB) ?

Answer 2

Wide QRS complexes with : An entirely negative QS complex in V1 (more rarely a wide rS complex, with a small r wave), and a wide, tall R wave without a q wave in V6. Secondary T wave inversions may also occur, just as in RBBB.

Question 3

Most characteristic finding from Left Anterior Fascicular Block is ?

Answer 3

Marked left axis deviation (about -45 degrees of more negative) . The finding of LAFB is a very common, nonspecific abnormality.

Question 4

Most characteristic finding from Left PosteriorFascicular Block is ?

Answer 4

Marked Right Axis Deviation (about +120 degrees or more positive).

Question 5

The diagnosis of a fascicular block is made primarily from which leads ?

Answer 5

From the mean QRS axis in the extremity (frontal plane) leads.