block (Wenckebach), nonconducted (blocked) PACs, and early transition (counterclockwise rotation). The rhythm is irregular, but there is a repeating pattern of longer and shorter RR intervals and ...

There are four main characteristics of PACs: Premature, occurring earlier than ... or the ectopic PR interval will be prolonged. The ECG will show a premature, ectopic P wave and then no QRS ...

This creates a pattern on the ECG called bundle branch block. It’s important to know whether you have any symptoms, such as chest pain, decreased exercise tolerance or shortness of breath.