In the majority of cases, right bundle branch block produces no symptoms of the heart condition. The more common sign and symptoms encountered in RBBB includes:

• Syncope or fainting
• Near-syncope or the feeling of about to faint
• Bradycardia or slow heart rate
• Chronic fatigue
• Palpitations

• Asymptomatic

  The current 2010 ACCF/AHA Guidelines for Assessment of Cardiovascular Risk in Asymptomatic Adults recommend a resting ECG for cardiovascular risk assessment in asymptomatic adults with hypertension or diabetes19 (level of evidence: C). [academic.oup.com]

  When right bundle branch block (RBBB) pacing morphology appears in a patient with a permanent or temporary transvenous RV pacemaker, myocardial perforation or malposition of the pacing lead must be ruled out, even though the patient may be asymptomatic [ncbi.nlm.nih.gov]

• Atrial Septal Defect

  The discovery of an atrial septal defect (ASD) or ventricular septal defect (VSD) can be facilitated by the echocardiogram. [symptoma.com]

  Right bundle branch block may occur in other pathologies e.g. atrial septal defect (especially ostium secundum), myocardial ischaemia. [gpnotebook.com]

  Causes[edit] Common causes are Normal variant, Right ventricular hypertrophy or strain, Congenital heart disease such as atrial septal defect and Ischemic heart disease. [2] In addition, a right bundle branch block may also result from Brugada syndrome [en.wikipedia.org]

  Atrial septal defect, cardiomyopathy, coronary artery disease, Ebstein anomaly); iatrogenic (e.g. Cardiac catheterization, cardiac transplantation, post cardiac surgery); infectious (e.g. [wikidoc.org]

• Congestive Heart Failure

  The incidence of angina pectoris, myocardial infarction, valvular heart disease, cardiomegaly, congestive heart failure, advanced heart block or cardiac death in these men did not differ from that of the control group over the observation period. [ncbi.nlm.nih.gov]

  […] on congestive heart failure. [interventional-cardiology.imedpub.com]

  Abstract A 76 year old female, with medical history significant for systolic congestive heart failure, who presented to the emergency department with lethargy and abdominal pain with diarrhea for the past 3 weeks. [jbclinpharm.org]

  Five days before, he was admitted to the emergency department for asthenia and was diagnosed with atrial fibrillation and secondary congestive heart failure. [bjcardio.co.uk]

• Weakness

  Weak. Very weak. When one considers the power a franchisor has over the purchasor of a franchise when stipulating conditions – this can go down to location, number of required customers or sales per year etc – Lidl’s excuse is as poor as it gets. [jaccuse.wordpress.com]

  The association with coronary disease was weak in this study, so stress testing would seem optional, only if there was high suspicion of this disease and coronary angiography would probably be overkill in most subjects. [ahcmedia.com]

  Lower-extremity weakness in a teenager due to thyrotoxic periodic paralysis. J Emerg Med. 2017 Apr. 52(4):e133-e137. [Medline]. Marterer R, Hongchun Z, Tschauner S, Koestenberger M, Sorantin E. [emedicine.medscape.com]

  Serum creatine kinase (CK) levels were recorded and myositis was diagnosed if the patient had proximal muscle weakness with at least one of the following: elevated levels of CK, features of myositis on electromyography, and/or a characteristic muscle [journals.plos.org]

• Collapse

  There might also be sudden pauses in the electrical activity in your heart, which could lead to you feeling dizzy, lightheaded, or sometimes collapsing. [bhf.org.uk]

  Echocardiographic parameters in the assessment of right ventricular failure Echocardiographic parameters Pericardial fluid in diastole > 5 mm Right ventricular wall thickness > 5 mm Inferior vena cava diameter >21 mm, inspiration collapse < 50% suggesting [ekjm.org]

• Heart Disease

  Isolated right bundle branch block is generally regarded as a benign finding in the absence of underlying structural heart disease. [ncbi.nlm.nih.gov]

  pulmonary embolism, rheumatic heart disease, myocarditis, cardiomyopathy, or hypertension. [en.wikipedia.org]

  valvular heart disease or cardiomyopathy. [heart.bmj.com]

  […] conducting system (Lenegre disease) Hyperkalaemia Digoxin toxicity Ischaemic heart disease Rheumatic heart disease Right ventricular hypertrophy (cor pulmonale) Pulmonary embolus Cardiomyopathy Myocarditis Congenital heart disease (e.g. [medicalexamprep.co.uk]

• Cardiomegaly

  The incidence of angina pectoris, myocardial infarction, valvular heart disease, cardiomegaly, congestive heart failure, advanced heart block or cardiac death in these men did not differ from that of the control group over the observation period. [ncbi.nlm.nih.gov]

  Six independent predictors have been proposed: NYHA class III/IV (5 points), cardiomegaly on chest X-ray (5 points), left ventricular systolic dysfunction on echocardiogram (3 points), NSVT on Holter monitoring (3 points), low QRS voltage (2 points) and [escardio.org]

  Prognosis and Mortality Left bundle branch block An increasing number of papers, most based on epidemiology, have shown a strong association between LBBB and cardiovascular disease, more specifically hypertension, cardiomegaly, coronary artery disease [interventional-cardiology.imedpub.com]

  In the cohort of Thrainsdottir et al. it was observed that in men older than 60 years RBBB is associated with hypertension [3], DM and cardiomegaly, and in women of the same age only with hypertension. [tandfonline.com]

• Dizziness

  If you have RBBB and another heart condition, such as heart attack or heart failure; dizziness or fainting; or other blocks in your electrical system, you will be treated for the heart disease. [my.clevelandclinic.org]

  Get an Accident, Sickness and Unemployment Quote Some potential problems experienced by individuals who have right bundle branch block include: Breathlessness after exercise Dizziness Fainting [specialrisksbureau.co.uk]

  […] this as: BMJ 2002;324:535 David Da Costa, William J Brady, June Edhouse By arbitrary definition, a bradycardia is a heart rate of Many patients tolerate heart rates of 40 beats/min surprisingly well, but at lower rates symptoms are likely to include dizziness [doi.org]

  […] familial RBBB may be benign or, if it occurs in Kearns-Sayre syndrome or Brugada syndrome, potentially fatal Clinical Children with RBBB may have Hx of congenital heart disease, heart surgery–eg, VSD, palpitations, ↓ energy/activity/exercise tolerance, dizziness [medical-dictionary.thefreedictionary.com]

• Stroke

  Although cardiac resynchronization therapy-defibrillator (CRT-D) was implanted in a heart failure patient with CRBBB, dyssynchrony worsened and stroke volume decreased, and this patient was re-admitted due to exacerbated heart failure. [ncbi.nlm.nih.gov]

  Clinical cardiovascular disease at the baseline was defined by any of the following: a history of myocardial infarction, angina pectoris, heart failure, valvular heart disease, cardiomyopathy, and stroke. [kjim.org]

  Connolly SJ, Kerr CR, Gent M et al (2000) Effects of physiologic pacing versus ventricular pacing on the risk of stroke and death due to cardiovascular causes. N Engl J Med 342:1385–1391 CrossRef PubMed Google Scholar 33. [doi.org]

  Ventricular interdependence may result in impaired LV filling, a decrease in LV stroke volume, and low cardiac output. [ekjm.org]

  Clinical Information, Serologic Testing, and Vital Status Age, gender, ethnicity, history of smoking, hypertension, coronary artery disease (CAD), previous stroke, SSc disease type (based on the extent of skin involvement), modified Rodnan Skin Score [journals.plos.org]

The following tests and diagnostic modalities are implored in the diagnosis of right bundle branch blocks:

• Electrocardiography (ECG): This makes use of multiple electrodes place on the chest of the patient to record the cardiac electrical activities. Often times, RBBB is an incidental ECG finding while another cardiac disease is being worked up.
• Echocardiogram: The use of a two dimensional echocardiograph can elucidate a detailed view of the cardiac structures. This can demonstrate the actual movement of the heart wall, muscles and valves. The discovery of an atrial septal defect (ASD) or ventricular septal defect (VSD) can be facilitated by the echocardiogram. 
• Holter monitoring: A continuous ambulatory monitoring of the cardiac electrical activity may be indicated in post-operative cases who undergone VSD or tetralogy of Fallot cardiac repair [9].

• Wide QRS Complex

  These are the criteria for multifocal atrial tachycardia MAT, also known as chaotic atrial rhythm,1 chaotic atrial tachycardia,2 and chaotic atrial mechanism.3 The wide QRS complexes ≥ 0.12 s with broad S waves in leads I, aVL, and the lateral precordial [ncbi.nlm.nih.gov]

  The computer is measuring the QRS duration here at 132 ms (0.132 s) which is greater than 120 ms (0.12 s). So we have a supraventricular rhythm with wide QRS complexes. [ems12lead.com]

  Right bundle branch block As illustrated in the electrocardiogram below, right bundle branch block presents with delayed activation of the right ventricle, leading to a wide QRS complex lasting greater than 0.12 seconds. [meds.queensu.ca]

• ST Elevation

  The ST elevation in lead V1 in anterior wall infarction and right bundle branch block may merge with the R' and cause a further QRS widening as an "equivalent" to the ST elevation. [ncbi.nlm.nih.gov]

  Usually, but not always, RBBB has an inverted T-wave with up to 1 mm ST depression in leads V2 and V3, so these upright T's with slight ST elevation is highly suspicious for anterior STEMI. The ST elevation in lateral leads is diagnostic. [hqmeded-ecg.blogspot.com]

• Right Bundle Branch Block

  […] features and inclusion criteria of complete left or right bundle branch block Apply the process for measurement to determine the presence of left or right complete bundle branch block Analysis of ECGs People may choose to analyze ECG’s in a number of [ekg.academy]

  […] to the right bundle branch.[2] Increased right intraventricular pressure, either acutely by pulmonary embolism or chronically as in cor pulmonale, can stretch the right bundle branch causing a bundle branch block.[7] RBBB can also be induced iatrogenically [ncbi.nlm.nih.gov]

  ECG (Example 1) Right Bundle Branch Block (RBBB) ECG (Example 2) Right Bundle Branch Block (RBBB) ECG (Example 3) Right Bundle Branch Block (RBBB) ECG (Example 4) Right Bundle Branch Block (RBBB) ECG (Example 5) Right Bundle Branch Block (RBBB) ECG (Example [healio.com]

• Left Anterior Fascicular Block

  We report the case of an acute anterior wall ST elevation myocardial infarction with new left anterior fascicular block and pre-existing right bundle branch block. [ncbi.nlm.nih.gov]

  Right Bundle branch Block, Left Anterior Fascicular Block, and First Degree AV Block Although the combination of right bundle branch block, left anterior or posterior fascicular block, and first degree AV block is often called “trifascicular block” the [ecgmedicaltraining.com]

• First-Degree Atrioventricular Block

  We present a case of near-normalization of the QRS by septal pacing in a patient with dual-chamber pacemaker and underlying complete right bundle branch block and first degree atrioventricular block. [ncbi.nlm.nih.gov]

  Figure 1. 12 lead ECG showed sinus rhythm, first-degree atrioventricular block (PR interval prolongation of 210 ms), complete right bundle branch block with a convex ST-segment elevation and negative T waves in precordial leads (V1-V6). [escardio.org]

  […] the first degree atrioventricular block,the type B WPW syndrome in group B is significantly higher thanthose in group A (75%vs,20%, P =0 010;71%vs,27%, P =0 005,44%vs,0%, P =0 020;31%vs,0%, P =0 019)。 [dict.cnki.net]

  Non-specific ST-T wave changes and first degree atrioventricular block were significantly associated with elevated right ventricular systolic pressure on echocardiogram while RBBB and ECG findings indicative of pulmonary hypertension showed a trend for [journals.plos.org]

• T Wave Inversion

  Delayed activation of the right ventricle also gives rise to secondary repolarization abnormalities, with ST depression and T wave inversion in the right precordial leads. [lifeinthefastlane.com]

  The ECG revealed new findings, including normal sinus rhythm, (RBBB), multiple ST segment abnormalities, S1Q3T3 pattern, and T wave inversion V1-V3. [journals.lww.com]

  These included the documentation of sustained VT of the morphology described in Table 1 (arrhythmia criteria), the presence of epsilon waves (depolarization criteria) and T-wave inversions in [V.sub.1], [V.sub.2], and [V.sub.3] in the absence of complete [medical-dictionary.thefreedictionary.com]

  - Wide S-wave in lateral leads ( Lead I, V5-6, aVL) - There will also be T wave inversion in the anterior leads - There may be an extra R wave in the anterior leads ( R'), or there may just be a broad slurred QRS. - The depolarization of the right ventricle [derangedphysiology.com]

• Electrocardiogram Change

  Electrocardiogram changes are common and precede the development of hypotension and neurological deterioration, therefore close watch on ECG monitoring is strongly recommended in the patients of TCAs poisoning. References 1. [mjdrdypu.org]

Patients presenting with asymptomatic heart block or a first degree heart block do not require any treatment. However, in RBBB presenting with an underlying condition, treatment may be necessary to control the disorder.

These may require the intake of medications to control hypertension or diabetes as the primary underlying cause. An invasive coronary angioplasty may be done to repair the blocked coronary arteries to relieve the impending RBBB.

In patients presenting with recurrent fainting, the implantation of an internal pacemaker may prevent further fainting spells. The pacemaker will generate regular electric impulses to regulate heart rhythm and ensure an optimal cardiac pumping.

Some forms of naturally occurring right bundle branch block like familial bundle branch block has a good prognostic outcome. Post VSD repair scarring of heart tissues may present eminently of electrophysiologic studies but may prove to be benign in the long run. However, cardiac scarring due to the tetralogy of Fallot repair have increases risk of cardiac arrhythmia and sudden cardiac death.

ECG finding of right bundle branch block associated with the Brugada syndrome [6], arrhythmogenic right ventricular cardiomyopathy (ARVC) [7], and Kearne-Sayre syndrome are also at high risk with sudden cardiac death and arrhythmia; thus, carry a grim prognosis in patients [8].

Complications

The following cardiac conditions are common complications associated with the right bundle branch block:

• Symptomatic bradycardia: The right bundle branch block may consequently slow down the rate of conduction and heart rate causing significant symptoms requiring pacemaker installation in most patients.
• Sudden cardiac death occurs when the bundle branch completely fails to transmit electrical impulses and results to cardiac arrest.
• Misdiagnosis of cardiac diseases: The ongoing RBBB may distort or complicate ECG readings of other heart disorders like myocardial infarction causing a delay in management and an increase in the mortality and morbidity rate in patients.

The following medical conditions can directly cause right bundle branch block in patients:

• Atrial septal defect
• Myocardial infarction 
• Viral or bacterial myocarditis
• Hypertension
• Scar tissue after heart surgery
• Pulmonary embolism
• Hereditary or familial bundle branch blocks [1]
• Family history of unexplained sudden cardiac death [2]
• Maternal human immunodeficiency virus (HIV) infections [3]

In the United States, the most common cause of right bundle branch block among children is post-surgical repair scarring of ventricular septal defect (VSD). The incidence rate for RBBB in the surgical repair of VSD alone is 25-81% and up to 60-100% after surgical cardiac repair in tetralogy of Fallot.

The long term effect of surgically induced RBBB in VSD repair has no major hemodynamic significance on the patient. However, in patients who underwent repair of the tetralogy of Fallot may consequently have QRS prolongation of up to 180 milliseconds and may carry some risk for arrhythmia and sudden cardiac death.

A number of trained athletes my present with complete and incomplete RBBB by voltage that points to an innocent physiologic cardiac remodeling phenomenon of the right atrium [4].

The basic pathophysiological defect in right bundle branch block is primarily due to the non-conduction of electrical impulses from the bundle of His to right bundle branch tracks.

In the advent that the left bundle branch conducts normally, right ventricular depolarization becomes significantly discordant with the left ventricle. This ventricular depolarization mismatch gives out the characteristic electrocardiograph (ECG) reading. There are rare cases of exercise induced right bundle branch block which are presenting similarly but are clinically benign [5].

Not all right bundle branch block conditions are preventable. However, RBBB can effectively be prevented by keeping the heart healthy to avert cardiac conditions that results to RBBB. The following useful tips can reduce the risk for coronary artery disease that can lead to RBBB:

• A regular healthy diet that is low on cholesterols and fats.
• Regular cardio exercise in up to 30 minutes minimum per week.
• Maintaining an ideal body weight.
• Quitting cigarette smoking.
• Control of hypertension with maintenance antihypertensive medications.
• Active control of diabetes.
• Prompt treatment of hypercholesterolemia and triclyceridemia.
• Regular follow-up with cardiologist for post-operative cardiac patients [10].

Right bundle branch block (RBBB) refers to a clinical condition wherein the transmission of impulses  towards the right ventricle is significantly delayed. The blockage of the right sided electrical pathway can make it difficult for the heart to pump efficiently. There are no specific treatment for RBBB and all management is geared towards the resolution of the underlying cardiac disease.

Definition

Right bundle branch block (RBBB) is clinically defined as a significant delay in the transmission of electrical impulse from the AV node to the right bundle branch of the heart.

Cause

Atrial septal defect, myocardial infarction, recent cardiac surgery, infectious myocarditis, pulmonary embolism, and familial bundle branch block may lead to this disorder.

Symptoms

Fainting, near fainting, chronic fatigue, and palpitations are common symptoms of RBBB.

Diagnosis

Electrocardiography, echocardiography, and Holter monitoring may be necessary to diagnose the condition.

Treatment and follow-up

Management of underlying cardiac cause and pacemaker installation are common treatment options.

1. 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. Dec 1998; 91(12):1465-74.
2. Finnish Medical Society Duodecim. Myocardial infarction. In: EBM Guidelines. Evidence-Based Medicine. Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2008 Apr 2.
3. 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. Oct 2005; 85(4):233-40.
4. Kim JH, Noseworthy PA, McCarty D, Yared K, Weiner R. Significance of electrocardiographic right bundle branch block in trained athletes. Am J Cardiol. 2011; 107(7):1083-9 
5. 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. Mar 1 2010; 105(5):677-80.
6. 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. Apr 2000; 46(1):55-65.
7. Marcus FI, McKenna WJ, Sherrill D, Basso C, Bauce B, Bluemke DA, et al. Diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia: proposed modification of the Task Force Criteria. Eur Heart J. Apr 2010; 31(7):806-14.
8. van Beynum I, Morava E, Taher M, Rodenburg RJ, Karteszi J, Toth K, et al. Cardiac arrest in kearns-sayre syndrome. JIMD Rep. 2012; 2:7-10.
9. Jain R, Dalal D, Daly A, et al. Electrocardiographic features of arrhythmogenic right ventricular dysplasia.Circulation. Aug 11 2009; 120(6):477-87.
10. 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. May 1 2014