Rhythm strip

Definition

A prolonged recording from one lead, used mainly to assess heart rate and rhythm rather than waveform shape across leads; a standard rhythm strip is 25 cm long (10 seconds). Lead II is most commonly used because it usually gives a good view of the P wave. At the standard 25 mm/s each small box equals 0.04 s and each large box 0.20 s, and the rate of an irregular rhythm can be estimated by counting the intervals between QRS complexes in the 10-second strip and multiplying by six.