Bundle Branch Block | Reference Guide
EKG Features
Rate: The underlying rateRhythm: Regular
P Wave: Normal
PR Interval: Normal (0.12-0.20 sec)
QRS: Wide (>0.12 sec)
A bundle branch block is a partial or total interruption of the heart’s electrical impulse in either the right or left branch of the electrical pathway. This interruption, or block, causes the electrical signals for one of the ventricles to detour, so that one of the ventricles contracts slightly later than the other ventricle. As a result, cardiac output can drop. This condition can be congenital or caused by heart disease.
External Source: http://www.heart.org/HEARTORG/Conditions/Arrhythmia/AboutArrhythmia/Conduction-Disorders_UCM_302046_Article.jsp
American Heart Association
Bundle Branch Block | Reference Guide Example

Authors, Reviewers and Developers
EKG rhythms classes: Thomas O'Brien.EKG monitor simulation: Steve Collmann
12 Lead Lecture: Dr. Michael Mazzini, MD, Cardiologist.
Spanish EKG: Breena R. Taira, MD, MPH
Medical review: Dr. Jonathan Keroes, MD, Cardiologist,
Dr. Barbara Erickson, PhD, RN, CCRN.
EKG tracings medical review: Dr. Pedro Azevedo, MD, Cardiology
Last Update: 11/7/2022
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