Official reprint from UpToDate®
www.uptodate.com ©2015 UpToDate®

Bradycardia in children

Frank Zimmerman, MD
Section Editor
John K Triedman, MD
Deputy Editor
Carrie Armsby, MD, MPH


Bradycardia is defined as a heart rate below the lowest normal values set for age. The heart rate is set by the cardiac electric conduction system that also synchronizes the timing of atrial and ventricular contractions. The conduction system includes the sinus node, atrioventricular node (AV), and the His-Purkinje system (His bundle). Bradycardia is caused by intrinsic dysfunction or injury to the heart's conduction system or by extrinsic factors acting on a normal heart and its conduction system.

Although bradycardia is less common in children than adults, it can infrequently cause significant morbidity and rarely sudden cardiac death. In particular, the risk of death in untreated children with complete block of the AV node is 5 to 8 percent [1]. With the advent of pediatric cardiac pacing, these deaths could be prevented. Hence, it is important for the clinician to identify those children with bradycardia who are at risk for morbidity and death and who might benefit from therapeutic intervention.

The diagnosis, evaluation, and treatment of bradycardia in children and adolescents will be discussed here.


The normal value for average heart rates varies with age. Younger patients have higher heart rates that decrease to adult values by the late teenage years. Bradycardia can be established by either using 12-lead electrocardiogram (ECG) or by 24-hour ambulatory monitoring.

Guidelines for bradycardia based on 12-lead ECG are as follows [1]:


Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Jun 2015. | This topic last updated: Oct 9, 2013.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2015 UpToDate, Inc.
  1. Michaelson M, Engle MA. Congenital complete heart block: An international study of the natural history. In: Cardiovascular Clinics, Brest AN, Engle MA (Eds), FA Davis, Philadelphia 1972. p.85.
  2. Kugler JD. Sinus node dysfunction. In: Pediatric Arrhythmias: Electrophysiology and Pacing, Gillette PC, Garson AG Jr (Eds), WB Saunders, Philadelphia 1990. p.250.
  3. Richards JM, Alexander JR, Shinebourne EA, et al. Sequential 22-hour profiles of breathing patterns and heart rate in 110 full-term infants during their first 6 months of life. Pediatrics 1984; 74:763.
  4. Southall DP, Johnston F, Shinebourne EA, Johnston PG. 24-hour electrocardiographic study of heart rate and rhythm patterns in population of healthy children. Br Heart J 1981; 45:281.
  5. Southall DP, Keeton BR, Leanage R, et al. Cardiac rhythm and conduction before and after Mustard's operation for complete transposition of the great arteries. Br Heart J 1980; 43:21.
  6. Montague TJ, Taylor PG, Stockton R, et al. The spectrum of cardiac rate and rhythm in normal newborns. Pediatr Cardiol 1982; 2:33.
  7. Fleming S, Thompson M, Stevens R, et al. Normal ranges of heart rate and respiratory rate in children from birth to 18 years of age: a systematic review of observational studies. Lancet 2011; 377:1011.
  8. Mangrum JM, DiMarco JP. The evaluation and management of bradycardia. N Engl J Med 2000; 342:703.
  9. Yabek SM, Jarmakani JM. Sinus node dysfunction in children, adolescents, and young adults. Pediatrics 1978; 61:593.
  10. Rein AJ, Simcha A, Ludomirsky A, et al. Symptomatic sinus bradycardia in infants with structurally normal hearts. J Pediatr 1985; 107:724.
  11. Bricker JT, Garson A Jr, Gillette PC. A family history of seizures associated with sudden cardiac deaths. Am J Dis Child 1984; 138:866.
  12. Beder SD, Cohen MH, Riemenschneider TA. Occult arrhythmias as the etiology of unexplained syncope in children with structurally normal hearts. Am Heart J 1985; 109:309.
  13. Recognition and management of bradycardia. In: Pediatric Advanced Life Support Provider Manual, Chameides L, et al (Eds), American Heart Association, Dallas 2011. p.113.
  14. Flinn CJ, Wolff GS, Dick M 2nd, et al. Cardiac rhythm after the Mustard operation for complete transposition of the great arteries. N Engl J Med 1984; 310:1635.
  15. Guidelines for Clinical Intracardiac Electrophysiological and Catheter Ablation Procedures. A report of the American College of Cardiology/American Heart Association Task Force on practice guidelines. (Committee on Clinical Intracardiac Electrophysiologic and Catheter Ablation Procedures). Developed in collaboration with the North American Society of Pacing and Electrophysiology. Circulation 1995; 92:673.
  16. Kleinman ME, Chameides L, Schexnayder SM, et al. Part 14: pediatric advanced life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation 2010; 122:S876.
  17. HISS RG, LAMB LE, ALLEN MF. Electrocardiographic findings in 67,375 asymptomatic subjects. X. Normal values. Am J Cardiol 1960; 6:200.
  18. Chiu SN, Lin LY, Wang JK, et al. Long-term outcomes of pediatric sinus bradycardia. J Pediatr 2013; 163:885.
  19. Guilleminault C, Coons S. Apnea and bradycardia during feeding in infants weighing greater than 2000 gm. J Pediatr 1984; 104:932.
  20. Fontán JP, Heldt GP, Heyman MB, et al. Esophageal spasm associated with apnea and bradycardia in an infant. Pediatrics 1984; 73:52.
  21. Kenigsberg K, Griswold PG, Buckley BJ, et al. Cardiac effects of esophageal stimulation: possible relationship between gastroesophageal reflux (GER) and sudden infant death syndrome (SIDS). J Pediatr Surg 1983; 18:542.
  22. Lombroso CT, Lerman P. Breathholding spells (cyanotic and pallid infantile syncope). Pediatrics 1967; 39:563.
  23. Stephenson JB. Reflex anoxic seizures ('white breath-holding'): nonepileptic vagal attacks. Arch Dis Child 1978; 53:193.
  24. Di Fiore J, Arko M, Herynk B, et al. Characterization of cardiorespiratory events following gastroesophageal reflux in preterm infants. J Perinatol 2010; 30:683.
  25. Swiryn S, McDonough T, Hueter DC. Sinus node function and dysfunction. Med Clin North Am 1984; 68:935.
  26. Mehta AV, Chidambaram B, Garrett A. Familial symptomatic sinus bradycardia: autosomal dominant inheritance. Pediatr Cardiol 1995; 16:231.
  27. Nordenberg A, Varghese PJ, Nugent EW. Spectrum of sinus node dysfunction in two siblings. Am Heart J 1976; 91:507.
  28. Lehmann H, Klein UE. Familial sinus node dysfunction with autosomal dominant inheritance. Br Heart J 1978; 40:1314.
  29. Ward DE, Ho SY, Shinebourne EA. Familial atrial standstill and inexcitability in childhood. Am J Cardiol 1984; 53:965.
  30. Benson DW, Wang DW, Dyment M, et al. Congenital sick sinus syndrome caused by recessive mutations in the cardiac sodium channel gene (SCN5A). J Clin Invest 2003; 112:1019.
  31. Ruschhaupt DG, Khoury L, Thilenius OG, et al. Electrophysiologic abnormalities of children with ostium secundum atrial septal defect. Am J Cardiol 1984; 53:1643.
  32. Bolens M, Friedli B. Sinus node function and conduction system before and after surgery for secundum atrial septal defect: an electrophysiologic study. Am J Cardiol 1984; 53:1415.
  33. Fournier A, Young ML, Garcia OL, et al. Electrophysiologic cardiac function before and after surgery in children with atrioventricular canal. Am J Cardiol 1986; 57:1137.
  34. Rakovec P, Rode P, Jakopin J, Horvat M. Latent sinoatrial conduction disturbances in symptomatic patients with Wolff-Parkinson-White syndrome. Pacing Clin Electrophysiol 1983; 6:2.
  35. Duster MC, Bink-Boelkens MT, Wampler D, et al. Long-term follow-up of dysrhythmias following the Mustard procedure. Am Heart J 1985; 109:1323.
  36. Kavey RE, Gaum WE, Byrum CJ, et al. Loss of sinus rhythm after total cavopulmonary connection. Circulation 1995; 92:II304.
  37. Colan SD, Liberthson RR, Cahen L, et al. Incidence and significance of primary abnormalities of cardiac rhythm in infants at high risk for sudden infant death syndrome. Pediatr Cardiol 1984; 5:267.
  38. Anderson KR, Hill RW. Occlusive lesions of cardiac conducting tissue arteries in sudden infant death syndrome. Pediatrics 1982; 69:50.
  39. Kozakewich HP, McManus BM, Vawter GF. The sinus node in sudden infant death syndrome. Circulation 1982; 65:1242.
  40. Bini RM, Westaby S, Bargeron LM Jr, et al. Investigation and management of primary cardiac tumors in infants and children. J Am Coll Cardiol 1983; 2:351.
  41. Bashour TT, Antonini C Sr, Fisher J. Severe sinus node dysfunction in obstructive jaundice. Ann Intern Med 1985; 103:384.
  42. Miller KK, Grinspoon SK, Ciampa J, et al. Medical findings in outpatients with anorexia nervosa. Arch Intern Med 2005; 165:561.
  43. Brucato A, Previtali E, Ramoni V, Ghidoni S. Arrhythmias presenting in neonatal lupus. Scand J Immunol 2010; 72:198.
  44. Baird TM. Clinical correlates, natural history and outcome of neonatal apnoea. Semin Neonatol 2004; 9:205.
  45. Epstein AE, DiMarco JP, Ellenbogen KA, et al. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. J Am Coll Cardiol 2008; 51:e1.
  46. Garson A Jr. Arrhythmias. In: The Electrocardiogram in Infants and Children: A Systematic Approach, Lea & Febiger, Philadelphia 1983. p.195.
  47. Ferrer PL. Arrhythmias in the neonate. In: Arrhythmias n the neonate, infant, and child, Roberts NK, Gleband H (Eds), Appleton-Century-Crofts, New York 1977. p.265.
  48. Ross BA, Trippel DL. Atrioventricular block. In: Garson A, Bricker JT, Fisher DJ, Neish SR, The science and practice of pediatric cardiology (Ed), Willilmans & Wilkins, Philadelphia 1998. p.2048.
  49. Brodsky M, Wu D, Denes P, et al. Arrhythmias documented by 24 hour continuous electrocardiographic monitoring in 50 male medical students without apparent heart disease. Am J Cardiol 1977; 39:390.
  50. Dickinson DF, Scott O. Ambulatory electrocardiographic monitoring in 100 healthy teenage boys. Br Heart J 1984; 51:179.