Nonconducted PACs and Junctional Escapes
Frank Yanowitz
Copyright 1996
Although at first glance this looks like 2nd degree AV block, the P waves indicated by the arrows are premature and not sinus P waves. The pause is long enough to encourage a junctional escape focus to take over. Note the sinus P waves just before the escape beats. Had the escapes not occurred, the sinus impulses would have captured the ventricles.