6-second ECG shows 5 QRS complexes at a normal rhythm followed by a "skipped beat" before resuming normal rhythm

6-second ECG shows 7 QRS complexes with a wavelike pattern between each complex and no identifiable P wave

6-second ECG shows 12 QRS complexes preceded by a P wave and followed by a T wave on a 6-second strip

6-second ECG shows 4 QRS complexes preceded by a P wave and followed by a T wave on a 6-second strip