II. Interpretation: General

  1. Heart Rate may be estimated from a regular pulse
    1. Count pulses for 6 seconds and multiply by 10
    2. Count pulses for 15 seconds and multiply by 4
  2. Maximal Heart Rate predicted by Age (may be used for Exercise target, typically 60-80% of maximum)
    1. Maximal Heart Rate = 220 - Age
    2. Women may be better estimated with St. James Women Take Heart Project Calculation
      1. Maximal Heart Rate = 206 - (Age * 0.88)
      2. Gulati (2010) Circulation 122(2):130-7 +PMID: 20585008 [PubMed]
  3. Heart Rate changes during respiration (respiratory variation)
    1. Heart Rate increases during inspiration
    2. Heart Rate decreases during expiration

III. Interpretation: Estimate from EKG Tracing

  1. Count Complexes in a 6 second EKG or Telemetry strip
    1. Normal recording is 25 mm/sec (5 large boxes per second, 30 per 6 seconds)
    2. Distance markers on EKG represent 15 large boxes (3 seconds)
    3. Count QRS Complexes between spanning 2 distance markers (30 large boxes, 6 seconds)
    4. Multiply complex count by 10 for Heart Rate per minute
  2. Interval between complexes
    1. Count large boxes (0.2 seconds) between complexes
    2. Divide 300 by box count: 300, 150, 100, 75, 60, 50
      1. 1 large box (200 ms or 0.2 seconds): 300 bpm
      2. 2 large boxes (400 ms or 0.4 seconds): 150 bpm
      3. 3 large box (600 ms or 0.6 seconds): 100 bpm
      4. 4 large boxes (800 ms or 0.8 seconds): 75 bpm
      5. 5 large box (1000 ms or 1.0 seconds): 60 bpm
      6. 6 large boxes (1200 ms or 1.2 seconds): 50 bpm
      7. 7 large box (1400 ms or 1.4 seconds): 43 bpm
      8. 8 large boxes (1600 ms or 1.6 seconds): 37 bpm

IV. Interpretation: Background

  1. Intrinsic Rates
    1. Atria: 75
    2. AV Node: 60
    3. Ventricle: 40
  2. Rough estimates to remember
    1. Infant: 160
    2. Preschool: 120
    3. Teen: 100
  3. Normal Heart Rate for age
    1. Infant: 100-160
    2. Toddler: 90-150
    3. Preschool: 80-140
    4. School-age: 70-120
    5. Teen and adult: 60-100
  4. References
    1. Diekmann (2006) Pediatric Education for Prehospital Professionals, Jones and Bartlett

V. Interpretation

  1. Bradycardia: under 60 (adults, see pediatric range above)
  2. Normal Sinus Rhythm: 60 to 100 (adults, see pediatric range above)
  3. Narrow Complex Tachycardia
    1. Sinus Tachycardia: over 100
    2. Supraventricular Tachycardia
      1. Infants: over 220
      2. Children: over 180
      3. Adults: over 160
  4. Wide Complex Tachycardia
    1. Ventricular Tachycardia
    2. Supraventricular Tachycardia with aberrancy

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Related Studies

Ontology: heart rate (C0018810)

Definition (ICF) Functions related to the number of times the heart contracts every minute.
Definition (ICF-CY) Functions related to the number of times the heart contracts every minute.
Definition (MSHCZE) Frekvence, kterou se srdce stahuje (tepe), počet tepů udávaný obv. za 1 minutu. SF bývá v klidu mezi 60–90 údery za minutu, u trénovaných osob (sportovců) bývá nižší. Její zrychlení se označuje jako tachykardie, zpomalení jako bradykardie. SF můžeme přesně zjistit pomocí EKG. (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ )
Definition (NCI_CDISC) The number of heartbeats per unit of time, usually expressed as beats per minute. (NCI)
Definition (NCI) The number of heartbeats per unit of time, usually expressed as beats per minute.
Definition (MSH) The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
Definition (CSP) number of times the heart ventricles contract per unit of time.
Concepts Clinical Attribute (T201)
MSH D006339
SnomedCT 250764009, 80042002, 364075005
LNC LP91312-6, LP32063-7, MTHU003114
English Heart Rate, Heart Rates, Rate, Heart, Rates, Heart, HR - Heart rate, cardiac rate, cardiac rates, heart rates, Heart rate (observable) (observable entity), Cardiac rate (observable entity), HR, Heart rate, Heart rate (observable entity), Cardiac rate, NOS, Heart rate, NOS, Cardiac rate (function), Heart rate (observable), Cardiac Rate, Cardiac rate, Cardiac rate, function (observable entity), heart rate
Swedish Hjärtfrekvens
Japanese シンパクスウ, 心拍周期性, 心拍数, 脈拍数
Czech srdeční frekvence, Srdeční frekvence
Finnish Sydämen syketiheys
German Herzfrequenz, Herzschlagfrequenz
Russian KHRONOTROPIZM SERDECHNYI, SERDECHNYI RITM, SERDTSA RITM, SERDECHNYKH SOKRASHCHENII CHASTOTA, СЕРДЕЧНЫЙ РИТМ, СЕРДЕЧНЫХ СОКРАЩЕНИЙ ЧАСТОТА, СЕРДЦА РИТМ, ХРОНОТРОПИЗМ СЕРДЕЧНЫЙ
Croatian SRČANA FREKVENCIJA
Polish Częstość pracy serca, Częstość skurczów serca
Hungarian Szívfrekvencia
Norwegian Hjertefrekvens, Hjerteslagfrekvens
Spanish latidos cardíacos (entidad observable), latidos cardíacos, frecuencia cardíaca (entidad observable), frecuencia cardíaca (función), frecuencia cardíaca, Frecuencia cardiaca, Frecuencia Cardíaca
Portuguese Frequência de Pulsação, Frequência cardíaca, Frequência Cardíaca
Dutch hartfrequentie, Frequentie, hart-, Hartfrequentie, Chronotropie, cardiale, Polsfrequentie
French Fréquence cardiaque, Rythme cardiaque
Italian Frequenza cardiaca