TY - JOUR T1 - Making sense of the paediatric ECG: rate and rhythm JF - Archives of disease in childhood - Education & practice edition JO - Arch Dis Child Educ Pract Ed SP - 26 LP - 27 DO - 10.1136/archdischild-2020-319125 VL - 107 IS - 1 AU - Chris Oakley AU - Mike Harris AU - Mohammad Ryan Abumehdi Y1 - 2022/02/01 UR - http://ep.bmj.com/content/107/1/26.abstract N2 - A fit, well, asymptomatic 6-year-old girl was referred to clinic for a murmur. Her ECG is shown in figure 1.Figure 1 Patient’s ECG.Rate, rhythm and PR intervalThe median heart rate for a 6-year-old girl is 89 bpm (range 68–115 bpm (2nd–98th centile)).1 Here, the ventricular rate is 5–6 large squares (50-60 bpm), signifying bradycardia. The atrial rate is faster (three large squares, 100 bpm). Some P waves are obscured within T waves or QRS complexes. The P waves are not related in the normal way to the QRS complexes. Therefore, the PR interval cannot be calculated.Complete heart block (CHB)The atrial and ventricular rates are different, with a complete lack of relationship (dissociation) between atrial and ventricular depolarisation. In this case, the escape rhythm originates from the His Bundle resulting … ER -