Atrial fibrillation: heart rate measured by apical pulse was more accurate than radial

Clinical bottom line (level 5)

  1. Both radial and apical pulse rates are inaccurate for measuring the true heart rate in atrial fibrillation (on average by 20 beats/minute and 10 beats/minute respectively).
  2. Measuring the apical pulse is more accurate than measuring the radial pulse (on average by 10 beats/minute).
  3. Measuring the pulse for 60 seconds is slightly more accurate than 15 or 30 seconds, but only by 2 beats/minute.
Sneed and Hollerbach: Heart and Lung 1992; 21: 427-433
Expires November 2003

The study

Setting: teaching hospital, USA

94 patients nurses measuring the apical pulse of one man with chronic atrial fibrillation 564 times

Independent ?blinded reference standard, applied in all patients from a non-consecutive inappropriate spectrum.
Reference standard:
  • ECG monitoring
Diagnostic test: apical and radial pulse measured over 15, 30 and 60 seconds.

The evidence

  • radial pulse mean error (beats/minute)
    • 15 sec: 19
    • 30 sec: 21
    • 60 sec: 19
  • apical pulse mean error (beats/minutes)
    • 15 sec: 11
    • 30 sec: 10
    • 60 sec: 8
  • mean difference between apical and radial rates: 10 beats/minute
  • Counting for 60 seconds was found to be more accurate than for 15 or 30 seconds (by 2 beats/minute; p < 0.05). However the difference was not considered to be clinically significant.

Comments

  1. 86% of counts were underestimates of the true rate.

Citation

  1. Sneed NV, and Hollerbach AD: Accuracy of heart rate assessment in atrial fibrillation. Heart and Lung 1992; 21: 427-433
Search Terms: atrial near fibrill* in Cochrane
Contributor: Chris Ball and Clare Wotton, November 1999
Reviewer:

Clinical Question.
Patient chronic atrial fibrillation
Intervention or Exposure atrial or radial pulse rate
Outcome heart rate