Chapter 10- Bundle Branch Block

right bundle branch block

normal impulses until the bundle of his is reached, the impulse must reverse and complete depolarization via the left ventricle. the change is direction creates the RSR pattern, can be viewed in V1 and V6

bundle branch block (BBB)

occurs when one or both of the ventricular pathways is damaged or delayed has p wave and wide QRS greater than .12 sec

Leads I, III, III

LBBB and RBBB will be the same in what leads?

negative deflection

LBBB create what type of QRS deflection?

The P wave preceding each QRS

indicated the impulse in coming from the SA node

Left bundle branch block (LBBB)

A block in the electrical conduction through the left bundle; evidenced by a wide QRS in lead V1 and V6

QS complex

A deep Q/S wave with no preceding R wave. Can indicate a left bundle branch block.

cardiac disease, drugs or. MI

BBB may be a cause of

positively deflected

Is RBBB positively deflected or negatively deflected?

where RBBB and LBBB can be seen

V1 and V6

no, but the underlying condition causing them might be, ex: myocardial infarction

are BBBs life threatening?

RSR pattern

change in impulse direction from right to left

wide QRS

delay in ventricular depolarization/BBB

supraventricular rhythm

evidence of P waves can be referred to as

underlying rhythm

the heart rhythm that would be present if the abnormal impulses were ignored or removed from the tracing

pacemaker for 24 hrs, may require permanent pacemaker or emergency cardiac care

treatment for bundle branch

the basic rhythm along with the BBB

what must always be determined with a BBB

V1 and V6 (precordial leads)

where specific characteristics of the BBB can be viewed

V1

which lead can distinguish RBBB from LBBB?

Right bundle branch block (RBBB) classification

widened QRS (>0.12s); double peaked "rabbit ears" QRS in V1 (best to look in V1 and V2); T wave can look abnormal - inverted