A patient presents in the emergency room (ER) with complaints of chest pain. The electrocardiogram (EKG) shows regular PR interval with a QRS wave missing every third beat. The nurse evaluates the EKG and recognizes this rhythm as which of the following? )
Explanation
•In a Mobitz type II second-degree AV block, the blockage of electrical impulses occurs below the AV node, either in the Bundle of His or one of the bundle branches.
•Each time the conduction is blocked, it causes the ventricles to skip a contraction, leading to the missing QRS waves on the EKG.
•The PR interval remains steady because the electrical impulse travels normally through the AV node but is blocked further along in the conduction pathway.