title: Heart rate, PR, and QT intervals in normal children: a 24-hour Holter monitoring study.
abstract: A dynamic electrocardiographic Holter monitoring study was performed in 32 healthy children (20 males and 12 females, age range 6-11 years old), without heart disease, according to clinical and noninvasive instrumental examination. We evaluated atrioventricular conduction time (PR), heart rate (HR), and QT interval patterns defining the range of normality of these electrocardiographic parameters. The PR interval ranged from 154 +/- 10 ms (mean +/- SD) for HR less than or equal to 60 to 102 +/- 12 ms for HR greater than or equal to 120 (range 85-180). The absolute mean HR was 87 +/- 10 beats/min (range 72-104), the minimum observed HR being 61 +/- 10 (range 51-79), the maximum 160 +/- 20 beats/min (range 129-186). Daytime mean HR gave a mean value of 93 +/- 10 (range 71-148), while during night hours it was 74 +/- 11 (range 54-98). The minimum QT interval averaged 261 +/- 10 ms for HR greater than 120 and the maximum 389 +/- 9 ms for HR less than or equal to 60; the corresponding mean value of QTc (i.e., QT corrected for HR) ranged from 388 +/- 8 for HR less than or equal to 60 beats/min to 403 +/- 14 ms for HR greater than 120 beats/min. The results of the present study provide data of normal children which can be readily compared against those of subjects in whom cardiac abnormalities are suspect or patient.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Institute of Internal Medicine, II School of Medicine, University of Naples, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Romano
authors.forename: M
authors.initials: M
authors.lastname: Clarizia
authors.forename: E
authors.initials: E
authors.lastname: Onofrio
authors.forename: M R
authors.initials: MR
authors.lastname: Caiazzo
authors.forename: L
authors.initials: L
authors.lastname: Adinolfi
authors.forename: S
authors.initials: S
authors.lastname: Cutillo
authors.forename: M
authors.initials: M
authors.lastname: Chiariello
authors.forename: M
authors.initials: M
authors.lastname: Condorelli
mesh_terms: D002648:Child; D002940:Circadian Rhythm; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted