Approach Considerations

Laboratory studies

If myocarditis or cardiomyopathy seem to be reflected in the right bundle branch block (RBBB) pattern, consider troponin, creatine kinase (CK), erythrocyte sedimentation rate (ESR), and other laboratory tests for cardiomyopathy (eg, carnitine determination).

Procedures

Invasive cardiac catheterization and electrophysiologic testing may be necessary to evaluate patients at risk for heart block or ventricular tachycardia and to document cardiomyopathy, myocarditis, or coexisting hemodynamic abnormalities.

Electrocardiography

Electrocardiographic (ECG) findings in right bundle branch block (RBBB) reflect the underlying pathophysiology.

Transmission of the electrical impulse through the left bundle is normal, resulting in normal depolarization of the septum and left ventricle. This creates the initial R wave in lead V1 and the Q wave in V6.

The electrical impulse in the right bundle branch is delayed or not conducted. Therefore, the right ventricle depolarizes by means of cell-to-cell conduction that spreads from the interventricular septum and left ventricle to the right ventricle. This situation results in the characteristic ECG pattern shown in the image below.

Pediatric Right Bundle Branch Block. These electrocardiographs demonstrate a normal sinus rhythm and a sinus rhythm with a right bundle branch block.

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Right bundle branch block has been noted to alternate with left bundle branch block and infra-Hisian block.

ECG findings necessary to confirm the diagnosis of right bundle branch block include those discussed below.

For complete right bundle branch block, the duration of the QRS complex is prolonged for the patient's age. Maximum QRS durations are 0.07 seconds for newborns less than 6 days, 0.08 seconds for patients aged 1 week to 7 years, and 0.09 seconds for patients aged 7-15 years. Most pediatric cardiologists require a QRS duration greater than 0.12 seconds to make a diagnosis of complete right bundle branch block. QRS duration greater than 0.18 seconds is considered a risk factor for development of ventricular tachycardia and sudden death.

An rsR' or rR' pattern, with the initial r wave less than the R' or r', may be seen in leads V1-V3R (see the image below). The initial R wave represents septal activation, the S wave represents left ventricular activation, and the R' represents activation of the right ventricle from the septum and left ventricle.

Pediatric Right Bundle Branch Block. This image depicts the electrophysiologic events of right bundle branch block. AV = atrioventricular.

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The S wave, which represents right ventricular activation, is wide in leads I and V6 (see the image below).

Pediatric Right Bundle Branch Block. This image demonstrates a wide S wave.

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The QRS axis may be normal, or right or left axis deviation may be present.

The T wave is almost always inverted in lead V1 and may be inverted in V2. In the other precordial leads and in the limb leads, the T wave is directed opposite to the terminal portion of the QRS complex.

In patients with atrial septal defects, the rsR’ pattern, the so called “incomplete right bundle branch block,” may be seen and is thought to be due to right ventricular volume overload. The QRS duration is usually less than 0.10 sec.

Adult patients who had their VSDs closed during childhood and have complete right bundle branch block have reduced heart rate variability.^[20]The clinical significance of this observation is not known at this time.

Holter monitoring

Ambulatory ECG (ie, Holter monitoring) may be indicated in postoperative patients who are being periodically monitored or in patients with new right bundle branch block that has a poorly understood etiology and clinical effect.^[21]

Imaging Studies

Echocardiography (ECHO) or myocardial perfusion studies may be indicated if the right bundle branch block (RBBB) is new or if the patient may have coexisting cardiac problems that cannot be adequately assessed with routine electrocardiography (ECG). For example, the standard criteria for ventricular hypertrophy or ischemia are relatively unhelpful in a patient with a preexisting intraventricular conduction defect. Myocardial perfusion studies suggested left ventricular mechanical dyssynchrony in half of the right bundle branch block patients studied.^[22]

Treatment & Management

Stein R, Nguyen P, Abella J, Olson H, Myers J, Froelicher V. Prevalence and prognostic significance of exercise-induced right bundle branch block. Am J Cardiol. 2010 Mar 1. 105(5):677-80. [QxMD MEDLINE Link].
Stephan E, Chedid R, Loiselet J, Bouvagnet P. Clinical and molecular genetics of familial bundle branch block related to chromosome 19 [in French]. Arch Mal Coeur Vaiss. 1998 Dec. 91(12):1465-74. [QxMD MEDLINE Link].
Deschenes I, Baroudi G, Berthet M, et al. Electrophysiological characterization of SCN5A mutations causing long QT (E1784K) and Brugada (R1512W and R1432G) syndromes. Cardiovasc Res. 2000 Apr. 46(1):55-65. [QxMD MEDLINE Link].
Keller DI, Barrane FZ, Gouas L, et al. A novel nonsense mutation in the SCN5A gene leads to Brugada syndrome and a silent gene mutation carrier state. Can J Cardiol. 2005 Sep. 21(11):925-31. [QxMD MEDLINE Link].
Adams JC, Nelson MR, Chandrasekaran K, Jahangir A, Srivathsan K. Novel ECG criteria for right ventricular systolic dysfunction in patients with right bundle branch block. Int J Cardiol. 2013 Aug 20. 167(4):1385-9. [QxMD MEDLINE Link]. [Full Text].
Diogenes MS, Succi RC, Machado DM, et al. Cardiac longitudinal study of children perinatally exposed to human immunodeficiency virus type 1 [in Portuguese]. Arq Bras Cardiol. 2005 Oct. 85(4):233-40. [QxMD MEDLINE Link].
Meziab O, Abrams DJ, Alexander ME, et al. Utility of incomplete right bundle branch block as an isolated ECG finding in children undergoing initial cardiac evaluation. Congenit Heart Dis. 2018 May. 13(3):419-27. [QxMD MEDLINE Link].
van Beynum I, Morava E, Taher M, et al. Cardiac arrest in Kearns-Sayre syndrome. JIMD Rep. 2012. 2:7-10. [QxMD MEDLINE Link]. [Full Text].
Perez-Riera AR, Barbosa Barros R, Daminello-Raimundo R, de Abreu LC, Nikus K. Transient high-degree right bundle branch block masking the type 1 Brugada ECG pattern associated with possible transient early repolarization syndrome. Ann Noninvasive Electrocardiol. 2020 Jan. 25(1):e12673. [QxMD MEDLINE Link]. [Full Text].
Daga B, Minano A, de la Puerta I, et al. Electrocardiographic findings typical of Brugada syndrome unmasked by cocaine consumption [in Spanish]. Rev Esp Cardiol. 2005 Nov. 58(11):1355-7. [QxMD MEDLINE Link].
Marcus FI, McKenna WJ, Sherrill D, et al. Diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia: proposed modification of the Task Force Criteria. Eur Heart J. 2010 Apr. 31(7):806-14. [QxMD MEDLINE Link]. [Full Text].
Choi NH, Fremed M, Starc T, et al. MIS-C and cardiac conduction abnormalities. Pediatrics. 2020 Dec. 146(6):[QxMD MEDLINE Link]. [Full Text].
Veeram Reddy SR, Du W, Zilberman MV. Left ventricular mechanical synchrony and global systolic function in pediatric patients late after ventricular septal defect patch closure: a three-dimensional echocardiographic study. Congenit Heart Dis. 2009 Nov-Dec. 4(6):454-8. [QxMD MEDLINE Link].
Hui W, Slorach C, Dragulescu A, Mertens L, Bijnens B, Friedberg MK. Mechanisms of right ventricular electromechanical dyssynchrony and mechanical inefficiency in children after repair of tetralogy of Fallot. Circ Cardiovasc Imaging. 2014 Jul. 7(4):610-8. [QxMD MEDLINE Link].
Marterer R, Hongchun Z, Tschauner S, Koestenberger M, Sorantin E. Cardiac MRI assessment of right ventricular function: impact of right bundle branch block on the evaluation of cardiac performance parameters. Eur Radiol. 2015 Dec. 25(12):3528-35. [QxMD MEDLINE Link].
Karadeniz C, Atalay S, Demir F, et al. Does surgically induced right bundle branch block really effect ventricular function in children after ventricular septal defect closure?. Pediatr Cardiol. 2015 Mar. 36(3):481-8. [QxMD MEDLINE Link].
Vojtovic P, Kucera F, Kubus P, et al. Acute right ventricular resynchronization improves haemodynamics in children after surgical repair of tetralogy of Fallot. Europace. 2018 Feb 1. 20(2):323-8. [QxMD MEDLINE Link].
Gatzoulis MA, Balaji S, Webber SA, et al. Risk factors for arrhythmia and sudden cardiac death late after repair of tetralogy of Fallot: a multicentre study. Lancet. 2000 Sep 16. 356(9234):975-81. [QxMD MEDLINE Link].
[Guideline] Finnish Medical Society Duodecim. Myocardial infarction. In: EBM Guidelines. Evidence-Based Medicine [Internet]. Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2008 Apr 2. [Full Text].
Heiberg J, Eckerstrom F, Rex CE, et al. Heart rate variability is impaired in adults after closure of ventricular septal defect in childhood: A novel finding associated with right bundle branch block. Int J Cardiol. 2019 Jan 1. 274:88-92. [QxMD MEDLINE Link].
Jain R, Dalal D, Daly A, et al. Electrocardiographic features of arrhythmogenic right ventricular dysplasia. Circulation. 2009 Aug 11. 120(6):477-87. [QxMD MEDLINE Link]. [Full Text].
Sillanmaki S, Aapro S, Lipponen JA, et al. Electrical and mechanical dyssynchrony in patients with right bundle branch block. J Nucl Cardiol. 2020 Apr. 27(2):621-30. [QxMD MEDLINE Link].
Chevallier S, Forclaz A, Tenkorang J, et al. New electrocardiographic criteria for discriminating between Brugada types 2 and 3 patterns and incomplete right bundle branch block. J Am Coll Cardiol. 2011 Nov 22. 58(22):2290-8. [QxMD MEDLINE Link].
Becker AE, Anderson RH. Morphology of the human atrioventricular junctional area. In: Wellens JHH, Lie KI, Janse MJ, eds. The Conduction System of the Heart. Chicago: Lea & Febiger; 1976. 263-71.
Brugada J, Brugada R, Brugada P. Right bundle-branch block and ST-segment elevation in leads V1 through V3: a marker for sudden death in patients without demonstrable structural heart disease. Circulation. 1998 Feb 10. 97(5):457-60. [QxMD MEDLINE Link].
Brugada P, Brugada J. Right bundle branch block, persistent ST segment elevation and sudden cardiac death: a distinct clinical and electrocardiographic syndrome. A multicenter report. J Am Coll Cardiol. 1992 Nov 15. 20(6):1391-6. [QxMD MEDLINE Link].
Brugada P, Brugada R, Brugada J. Sudden death in patients and relatives with the syndrome of right bundle branch block, ST segment elevation in the precordial leads V(1)to V(3)and sudden death. Eur Heart J. 2000 Feb. 21(4):321-6. [QxMD MEDLINE Link].
Colvin EV. Cardiac embryology. In: Garson A, Bricker JT, Fisher DJ, Neish SR, eds. The Science and Practice of Pediatric Cardiology. 2nd ed. Baltimore, MD: Williams & Wilkins; 1998. 91-123.
Dubin D. Rapid Interpretation of EKGs. 3rd ed. Tampa, FL: Cover; 1984. 137-42.
Esscher E, Hardell LI, Michaelsson M. Familial, isolated, complete right bundle-branch block. Br Heart J. 1975 Jul. 37(7):745-7. [QxMD MEDLINE Link].
Ewing L. Bundle-branch and fasicular blocks. In: Gillette PC, Garson A, eds. Pediatric Arrhythmias: Electrophysiology and Pacing. Philadelphia: WB Saunders Co; 1990. 319-21.
Garson A. Interventricular conduction disturbances. The Electrocardiogram in Infants and Children: A Systematic Approach. Philadelphia, PA: Lea & Febiger; 1983. 119-42.
Garson A. Electrocardiography. In: Garson A, Bricker JT, Fisher DJ, Neish SR, eds. The Science and Practice of Pediatric Cardiology. 2nd ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 1998. 736.
Horowitz LN, Alexander JA, Edmunds LH Jr. Postoperative right bundle branch block: identification of three levels of block. Circulation. 1980 Aug. 62(2):319-28. [QxMD MEDLINE Link].
Husson GS, Blackman MS, Rogers MC, et al. Familial congenital bundle branch system disease. Am J Cardiol. 1973 Sep 7. 32(3):365-9. [QxMD MEDLINE Link].
James TN. The connecting pathways between the sinus node and A-V node and between the right and the left atrium in the human heart. Am Heart J. 1963 Oct. 66:498-508. [QxMD MEDLINE Link].
Kehoe RF, Bauernfeind R, Tommaso C, et al. Cardiac conduction defects in polymyositis: electrophysiologic studies in four patients. Ann Intern Med. 1981 Jan. 94(1):41-3. [QxMD MEDLINE Link].
Komajda M, Frank R, Vedel J, et al. Intracardiac conduction defects in dystrophia myotonica. Electrophysiological study of 12 cases. Br Heart J. 1980 Mar. 43(3):315-20. [QxMD MEDLINE Link].
Krongrad E. Prognosis for patients with congenital heart disease and postoperative intraventricular conduction defects. Circulation. 1978 May. 57(5):867-70. [QxMD MEDLINE Link].
Li TC, Hu DY, Bian H, et al. Effects of transcatheter closure of perimembranous ventricular septal defects: intermediate and long-term follow-up of 68 cases [in Chinese]. Zhonghua Yi Xue Za Zhi. 2005 Oct 26. 85(40):2846-9. [QxMD MEDLINE Link].
Massing GK, James TN. Anatomical configuration of the His bundle and bundle branches in the human heart. Circulation. 1976 Apr. 53(4):609-21. [QxMD MEDLINE Link].
Nery PB, Ha AC, Keren A, Birnie DH. Cardiac resynchronization therapy in patients with left ventricular systolic dysfunction and right bundle branch block: a systematic review. Heart Rhythm. 2011 Jul. 8(7):1083-7. [QxMD MEDLINE Link].
Ogura Y, Kato J, Ogawa Y, et al. A case of alternating bundle branch block in combination with intra-Hisian block. Int Heart J. 2005 Jul. 46(4):737-44. [QxMD MEDLINE Link].
Pickhoff AS. Electrophysiology; development and function of the cardiac conduction system. In: Allen HD, Gutgesell HP, Clark EB, Driscoll DJ, eds. Heart Disease in Infants, Children, and Adolescents: Including the Fetus and Young Adult. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2000. 414-24.
Priori SG, Napolitano C, Gasparini M, et al. Clinical and genetic heterogeneity of right bundle branch block and ST- segment elevation syndrome: A prospective evaluation of 52 families. Circulation. 2000 Nov 14. 102(20):2509-15. [QxMD MEDLINE Link].
Rossi L. Histopathology of Cardiac Arrhythmias. 2nd ed. Philadelphia, PA: Lea & Febiger; 1979. 1-75.
Sanyal SK, Johnson WW. Cardiac conduction abnormalities in children with Duchenne's progressive muscular dystrophy: electrocardiographic features and morphologic correlates. Circulation. 1982 Oct. 66(4):853-63. [QxMD MEDLINE Link].
Schaal SF, Seidensticker J, Goodman R, Wooley CF. Familial right bundle-branch block, left axis deviation, complete heart block, and early death. A heritable disorder of cardiac conduction. Ann Intern Med. 1973 Jul. 79(1):63-6. [QxMD MEDLINE Link].
Scheinman MM, Goldschlager NF, Peters RW. Bundle branch block. Cardiovasc Clin. 1980. 11(1):57-80. [QxMD MEDLINE Link].
Silka MJ. Bundle branch block. In: Garson A, Bricker JT, Fisher DJ, Neish SR, eds. The Science and Practice of Pediatric Cardiology. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998. 2033-6.
Simonsen EE, Madsen EG. Four cases of right-sided bundle-branch block and one case of atrioventricular block in three generations of a family. Br Heart J. 1970 Jul. 32(4):501-4. [QxMD MEDLINE Link].
Stephan E. Hereditary bundle branch system defect. A new genetic entity?. Am Heart J. 1979 Jun. 97(6):708-18. [QxMD MEDLINE Link].
Stephan E. Hereditary bundle branch system defect: survey of a family with four affected generations. Am Heart J. 1978 Jan. 95(1):89-95. [QxMD MEDLINE Link].
Sun XJ, Gao W, Zhou AQ, et al. Risk factors for arrhythmia early after transcatheter closure of perimembranous ventricular septal defects [in Chinese]. Zhonghua Er Ke Za Zhi. 2005 Oct. 43(10):767-71. [QxMD MEDLINE Link].
Sung RJ, Tamer DM, Garcia OL, et al. Analysis of surgically-induced right bundle branch block pattern using intracardiac recording techniques. Circulation. 1976 Sep. 54(3):442-6. [QxMD MEDLINE Link].
Tawara S. Das Reizleitungssystem des Saugetierkerzens. Jena: Gustav Fisher; 1906.
Udink ten Cate FE, van Heerde M, Rammeloo LA, Hruda J. Transientelectrocardiographic abnormalities following blunt chest trauma in a child. Eur J Pediatr. November 2008. 167(11):1331-3.
Van Praagh R, Van Praagh S. Morphologic anatomy. In: Fyler DC, ed. Nadas' Pediatric Cardiology. Philadelphia, PA: Hanley & Belfus; 1992. 23.
Waller BF, Schlant RC. Anatomy of the heart. In: O'Rourke RA, Schlant RC, Roberts R, et al, eds. Hurst's The Heart. 8th ed. New York, NY: McGraw-Hill Medical; 1994. 99-102.
Walsh, EP. Electrocardiography and introduction to electrophysiologic techniques. In: Fyler DC, ed. Nadas' Pediatric Cardiology. Philadelphia, PA: Hanley & Belfus; 1992. 134.
Yasui H, Yoshitoshi M, Komori M, et al. Cardiodynamic effects of experimental right bundle branch block in canine hearts with normal and hypertrophied right ventricles. Am Heart J. 1985 Jan. 109(1):69-77. [QxMD MEDLINE Link].
Ksiazczyk TM, Tomik A, Godlewski K, Werner B. Transient complete right bundle branch block following right heart catheterization in children - a report of two cases. Postepy Kardiol Interwencyjnej. 2016. 12(4):372-6. [QxMD MEDLINE Link].
Thornton MD. Lower-extremity weakness in a teenager due to thyrotoxic periodic paralysis. J Emerg Med. 2017 Apr. 52(4):e133-e137. [QxMD MEDLINE Link].
Gatzoulis MA, Till JA, Somerville J, Redington AN. Mechanoelectrical interaction in tetralogy of Fallot. QRS prolongation relates to right ventricular size and predicts malignant ventricular arrhythmias and sudden death. Circulation. 1995 Jul 15. 92(2):231-7. [QxMD MEDLINE Link]. [Full Text].
Zhou SH, Liebman J, Dubin AM, et al. Using 12-lead ECG and synthesized VCG in detection of right ventricular hypertrophy with terminal right conduction delay versus partial right bundle branch block in the pediatric population. J Electrocardiol. 2001. 34 suppl:249-57. [QxMD MEDLINE Link].

Media Gallery

Pediatric Right Bundle Branch Block. These electrocardiographs demonstrate a normal sinus rhythm and a sinus rhythm with a right bundle branch block.
Pediatric Right Bundle Branch Block. Anatomy of the penetrating portion of the atrioventricular (AV) bundle is shown.
Pediatric Right Bundle Branch Block. This image depicts the electrophysiologic events of right bundle branch block. AV = atrioventricular.
Pediatric Right Bundle Branch Block. Pathophysiology of right bundle branch block is described. AV = atrioventricular; LV = left ventricular; RV = right ventricular.
Pediatric Right Bundle Branch Block. This image depicts the electrophysiologic sequence of events that occur in normal cardiac conduction. AV = atrioventricular.
Pediatric Right Bundle Branch Block. This image demonstrates a wide S wave.

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Author

Glenn T Wetzel, MD, PhD Associate Professor of Pediatric Cardiology, John Hopkins University School of Medicine; Director, Pediatric Interventional Electrophysiology, John Hopkins Children's Center

Glenn T Wetzel, MD, PhD is a member of the following medical societies: Heart Rhythm Society

Disclosure: Nothing to disclose.

Coauthor(s)

Kenneth R Knecht, MD Assistant Professor of Cardiology, Department of Pediatrics, Arkansas Children's Hospital, University of Arkansas for Medical Sciences College of Medicine

Kenneth R Knecht, MD is a member of the following medical societies: American Academy of Pediatrics

Disclosure: Nothing to disclose.

Karine Guerrier, DO, MPH Assistant Professor, Division of Cardiology, Department of Pediatrics, University of Tennessee Health Science Center College of Medicine; Director, Cardiac Rhythm Device Management, Le Bonheur Heart Institute, Le Bonheur Children’s Hospital

Karine Guerrier, DO, MPH is a member of the following medical societies: American College of Cardiology, American Heart Association, Heart Rhythm Society, Pediatric and Congenital Electrophysiology Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Alvin J Chin, MD Emeritus Professor of Pediatrics, University of Pennsylvania School of Medicine

Disclosure: Nothing to disclose.

Chief Editor

Syamasundar Rao Patnana, MD Professor of Pediatrics and Medicine, Division of Cardiology, Emeritus Chief of Pediatric Cardiology, University of Texas Medical School at Houston and Children's Memorial Hermann Hospital

Syamasundar Rao Patnana, MD is a member of the following medical societies: American Academy of Pediatrics, American Pediatric Society, American College of Cardiology, American Heart Association, Society for Cardiovascular Angiography and Interventions, Society for Pediatric Research

Disclosure: Nothing to disclose.

Acknowledgements

The authors and editors of Medscape Drugs & Diseases gratefully acknowledge the contributions of previous authors Christopher Mart, MD; Kerry Rosen, MD; and Christopher Zachary, MD, to the development and writing of this article.