What medications can cause right bundle branch block

What medications can cause right bundle branch block

Based largely on a concern over QT prolongation and the development of life-threatening arrhythmias, a number of antipsychotic drugs have been temporarily or permanently withdrawn from the market or their use Aug 22, 2012 · Thyroid hormone has important physiological effects on the cardiovascular system []. Right bundle branch block comes from a problem with the heart’s ability to conduct electrical signals. Jun 11, 2022 · Bundle branch block. The presence of tall T waves in normally conducted beats in the right precordial leads (quantified as an S wave–to–T wave ratio of ≤1. Normal heartbeats start in the upper right heart chamber. If it’s taken in high dosages or for a long period, digitalis can cause first-degree heart block. Objectives: To establish the prevalence and incidence of RBBB in the general population without cardiovascular events (CVE) and whether RBBB increases cardiovascular morbidity and mortality compared with patients with a normal electrocardiogram (ECG). Thus, the right ventricle depolarizes by means of cell-to-cell conduction that spreads from the interventricular septum and left ventricle to the right ventricle. Normal QT interval. Nov 4, 2019 · ECG performed 5 minutes after infusion of lidocaine 100 mg reveals junctional escape rhythm with right bundle branch block and left anterior fascicular block at a heart rate of 60 bpm. 43% for left bundle-branch block among middle-aged men. heart failure. Pulmonary embolism. The most common cause of this is just being a normal variant, in other words, there is nothing wrong with the heart. In some cases, second-degree heart block will eventually progress to complete heart block. gov. In a healthy heart, the electrical signal for your An incomplete right bundle branch block (IRBBB) is a conduction abnormality in the right bundle branch block. cardiomyopathy. Dec 3, 2018 · Dr. They are common and can occur in a wide variety of clinical scenarios and a diverse population. Mar 23, 2023 · right bundle branch blocks are the most common branch block (more common than left bundle branch blocks) due to the right heart having a more anterior location 1-5; Etiology. Shortness of breath or difficulty breathing. Transient LBBB is less common than right bundle branch block (only 25% of Apr 28, 2015 · Due to reports of cardiovascular adverse events and observed physiological effects, the package inserts for stimulant drugs warn against use in patients with preexisting heart disease or cardiac structural abnormalities due to risk of sudden death, stroke, and myocardial infarction (MI). Mar 28, 2024 · Anatomy — The bundle of His divides at the juncture of the fibrous and muscular boundaries of the interventricular septum into the right and left bundle branches. Based largely on a concern over QT prolongation and the development of life-threatening arrhythmias, a number of antipsychotic drugs have been temporarily or permanently withdrawn from the market or their use Aug 15, 2022 · What is bundle branch block? Bundle branch block is a heart arrhythmia where one or both bundle branches are delayed or blocked entirely, causing the ventric Fascicular block involves the anterior or posterior fascicle of the left bundle branch. This is called the right atrium. (See also Overview of Abnormal Heart Rhythms and Overview of Heart Block . In bundle branch block, the pathway these impulses follow is delayed or blocked. 8) is Jul 2, 2021 · Recent analyses have demonstrated that COVID-19 patients with pre-existing cardiovascular risks and/or comorbidities have a higher risk of death in the short-term. Right bundle branch block is a problem in the heart’s electrical system. Therefore, the AHA / ACCF / HRS recommendations for The cause for bundle branch blocks can differ depending on whether the left or the right bundle branch is affected. If you have a newly diagnosed LBBB, it’s Jul 23, 2022 · The left bundle branch splits into anterior and posterior fascicles. Apr 22, 2022 · It is a class IC antiarrhythmic drug that inhibits inward sodium current through its dose-dependent blockade of voltage-gated calcium channels within the cardiac membrane. CME Programs. V6: broad, notched (‘M’-shaped) R wave. The co-occurrence of psychiatric disorders in cardiac patients might affect the clinical Jul 13, 2017 · Is it safe to take prescribed phentermine in the presence of known right bundle branch block (RBBB)? Is prescribed phentermine safe to take with a RBBB? The RBBB was only detected by EKG. RBBB can be a normal finding but it is Feb 24, 2017 · 9 cardiovascular events, including hypertension, palpitations, and tachycardia (no numbers of effect separately), 1 right bundle branch block, 1 prolonged QT interval/NR Findling et al. Particularly, the degree of AV block may increase. May 15, 2009 · Right bundle branch block, left bundle branch block, intra-ventricular conduction delay > 0. right ventricular strain (especially due to pulmonary embolism). 33/265 (12. More detailed information concerning RBBB is provided below: Bundle branch block. It can develop due to various reasons such as function and structural causes. Associated features include: Left axis deviation (LAD); Poor R wave progression in precordial leads, and. 1%. A diagnosis of ventricular tachycardia (VT) was made A more subtle form of cardiomyopathy, arrhythmogenic right ventricular dysplasia, which typically presents with a left bundle branch PVC pattern, also needs to be considered, and clinical clues to this disorder are the presence of inverted T-waves in leads V1 through V3, the presence of low amplitude potentials, delayed slurred QRS in leads V1 Mar 23, 2023 · right bundle branch blocks are the most common branch block (more common than left bundle branch blocks) due to the right heart having a more anterior location 1-5; Etiology. U-wave: No effect: QT (QTc) interval Jun 14, 2022 · Left bundle branch block (LBBB) occurs when something blocks or disrupts the electrical impulse that causes your heart to beat. Your heart uses electrical signals to cause the heart muscle to squeeze and keep pumping normally. Jul 13, 2017 · Is it safe to take prescribed phentermine in the presence of known right bundle branch block (RBBB)? Is prescribed phentermine safe to take with a RBBB? The RBBB was only detected by EKG. But if the pathway is blocked, the impulses may move slower than normal or Jan 2, 2018 · Cause of ventricular fibrillation and sudden unexpected death. Admission labs were notable for high-sensitivity troponin T (hs-TropT) of 36 ng/L, creatinine of 1. Whether bundle branch block is actually caused by drug use in a particular individual relates to many factors and can't be predicted for that individual without more information Right bundle branch block comes from a problem with the heart’s ability to conduct electrical signals. It has been shown to slow the conduction in the left bundle branch block. Jun 19, 2023 · Brugada syndrome is a genetic disorder that can cause life-threatening ventricular tachyarrhythmias and thereby sudden cardiac arrest and sudden cardiac death. LBBB = Left anterior fasicular block (LAFB) + Left posterior fasicular block (LPFB) Each branch of the left bundle branch may be damaged in isolation. This can cause serious symptoms such as a very slow heart rate, fainting, and chest pain. 1 to 13. This can have the side effect of delaying electrical conduction within the heart Dec 1, 2023 · The right bundle branch block is a block that will affect the right bundle branch, which can create problems for the heart to keep beating at a steady pace. While a complete RBBB has a QRS duration of 120 ms or more, an incomplete RBBB has a wave duration between 100 and 120 ms. Right bundle branch block (RBBB) occurs when transmission of the electrical impulse is delayed or not conducted along the right bundle branch. Bundle branch block: There is a flaw in the bundle branches, the pathways for the electrical impulse running along the right and left Dec 29, 2020 · More specific findings, suggestive of right ventricular strain, were encountered in only one-third of patients. There is a right and a left bundle branch, and damage to either will affect the electrical system of the respective side of the heart. May 5, 2022 · Loss of consciousness. Typically, patients have received radiation therapy for one of the following 1-5: mediastinal lymphoma; esophageal cancer; thymoma; lung cancer (especially left-sided) In general, “ conduction delay ” refers to a slight widening of the QRS complex, especially in the right precordial leads (leads V1, V2, and V3); it is sometimes also called incomplete right bundle branch block. Symptoms are also more common if the Can medications cause Right Bundle Branch Block? Although medications are not a common cause of RBBB, there are a number of drugs that have been associated with the condition. Apr 29, 2022 · The right bundle branch is a long, thin, discrete structure that consists of fast response Purkinje fibers. Anterior fascicle block, which is much more common, causes left axis deviation. See the image below. Jul 24, 2019 · Background: Right bundle branch block (RBBB) is among the most common electrocardiographic abnormalities. There is no evidence to suggest established RBBB carries other than a normal prognosis (1) Right bundle branch block may indicate pathology in the right side of the heart e. 5%) DBP >80–90 mmHg with increase of 10 mmHg The Reykjavik study showed a prevalence of 0. Typically, patients have received radiation therapy for one of the following 1-5: mediastinal lymphoma; esophageal cancer; thymoma; lung cancer (especially left-sided) Apr 28, 2015 · Due to reports of cardiovascular adverse events and observed physiological effects, the package inserts for stimulant drugs warn against use in patients with preexisting heart disease or cardiac structural abnormalities due to risk of sudden death, stroke, and myocardial infarction (MI). They can present in patients both with and without preexisting cardiac disease. ) The electrical current that controls the contraction of heart muscle starts in the sinoatrial node block, high-grade atrioventricular block, or third-degree atrioventricular block not caused by reversible or physiologic causes, permanent pacing is recommended regardless of symptoms. In a healthy heart, the electrical signal for your Sep 14, 2020 · Right bundle branch block (RBBB) is frequently found in the general healthy population. arrhythmogenic ventricular cardiomyopathy (ARVC), left bundle branch block (LBBB), and right bundle branch block (RBBB) with left anterior or posterior fascicular block. 5 Oct 23, 2019 · QRS > 120 ms in adults (>100 ms in children 4-16yo, and > 90 ms <4yo. 4-6 Furthermore, the FDA issued a safety announcement in A number of antipsychotic and antidepressant drugs are known to increase the risk of ventricular arrhythmias and sudden cardiac death. Figure 4. Other electrocardiographic presentations typical of PE include anterior T wave inversion and right bundle branch block [77,78]. Blood flows from the heart to the lungs through the pulmonary vein. It’s also possible that this condition can occur without a known cause. 12 The Tecumseh study showed the prevalence Dec 12, 2022 · A left bundle branch block (LBBB) is an abnormal finding on an ECG (electrocardiogram). These patients require thorough cardiological investigation to determine if lamotrigine can be administered safely. Right bundle branch block causes On the Web Most recent articles. V1: Dominant S wave. Interruption of the left anterior fascicle causes left anterior hemiblock characterized by modest QRS prolongation (< 120 millisecond) and a frontal plane QRS axis more negative than − 30 ° (left axis deviation). The right bundle branch courses down the right side of interventricular septum near the endocardium in its upper third, deeper in the muscular portion of the septum in the middle third, and then again near the endocardium in its lower third. It usually doesn’t cause symptoms unless you have some other heart condition. Rarely, hyperkalemia can alter the conduction physiology by slowing electrical impulse conduction through cardiac tissue, causing a right bundle branch AV system (AV node, His bundle, Purkinje system) Preexisting AV block, bundle branch block or fascicular block may become worse. In a healthy heart, the signal to start your heartbeat begins in the upper right chamber of the heart (right atrium). In a healthy heart, the electrical signal for your Feb 15, 2024 · Bundle branch block is a condition that occurs when there is a delay or blockage in the electrical signals that control the heart's contractions. Sometimes, there is no known cause. Possible cause: Bundle branch block can be congenital or acquired. This happens because of a block in the path that your electrical impulses follow. A note from Cleveland Clinic. Beta blockers: These drugs inhibit the part of the nervous system that speeds up the heart. Methods: Retrospective chart review of management of patients with BCT, RBBB without a history of ischaemic heart disease. In normal cardiac conduction, impulses travel equally down the left and right bundles, with the septum activated from left to right and the formation of small Q waves in lateral leads. US National Guidelines Clearinghouse Right bundle branch block in asymptomatic individuals is not correlated with adverse outcomes. Also, as you age, your heart Apr 29, 2022 · The right bundle branch is a long, thin, discrete structure that consists of fast response Purkinje fibers. Find these drugs listed on the page and be warned of similar symptoms as possible side-effects. The pathway includes two branches the left and the right bundles. [1] Reports show that frequent VPCs can cause progressive left Mar 19, 2020 · The cause for bundle branch blocks can differ depending on whether the left or right bundle branch is affected. A wide and notched R wave pattern may be seen in lead V1 and/or V2. These are usually distinct from any problem with AV conduction (ie, they usually coexist with normal sinus rhythm Apr 3, 2020 · Practice Essentials. Calvin Weisberger answered. It has a relatively high prevalence, a study conducted on young Swiss military conscripts with a mean age of 19 Feb 24, 2017 · 9 cardiovascular events, including hypertension, palpitations, and tachycardia (no numbers of effect separately), 1 right bundle branch block, 1 prolonged QT interval/NR Findling et al. Finally, a new right bundle branch block in patients experiencing dyspnea (particularly if acute) may Objective: To study the response of regular broad-complex tachycardia (BCT) demonstrating right bundle branch block (RBBB) to treatment in the Emergency department (ED). The classic S1Q3T3 pattern was seen in less than 10% of COVID-19-related PE . Characteristic ECG changes of right bundle branch block and S–T segment elevation leads V1–V3. 7 Phase 3 block (also called tachycardia‐dependent block) occurs when an impulse arrives at tissues that are still refractory caused by incomplete repolarization. Left bundle branch block may be due to conduction system degeneration or a reflection of myocardial pathology. 4 causes of right bundle branch blockage 1. Leads 1 and V6: S > R in duration OR >40 ms in leads I and V6 in adults. RBBB is caused by diseases that affect the right bundle branch or the myocardial region, where the right bundle branch is located. atrial septal defect (especially ostium secundum), myocardial ischaemia. The 2 upper chambers are called atria. Apr 3, 2023 · Ventricular premature complexes (VPCs), or premature ventricular complexes/contractions (PVCs), are ectopic beats that arise from within the ventricles. Jun 20, 2018 · pulmonary embolism. 4; p <0. Jun 11, 2022 · Tests that can be used to diagnose a bundle branch block or its causes include: Electrocardiogram (ECG or EKG). The electrical signals are passed to the ventricles, the main heart pumping chambers. Mar 26, 2019 · Painful left bundle branch block (LBBB) syndrome is a rare disorder in which a rate-related LBBB aberration causes debilitating exertional chest discomfort. Apr 22, 2022 · Flecainide is the first-line antiarrhythmic agent used in patients without structural heart disease. It is a class IC antiarrhythmic drug that inhibits inward sodium current through its dose-dependent blockade of voltage-gated calcium channels within the cardiac membrane. 15 In a retirement community, a prevalence of bundle-branch block of 5. It occurs from a change in the way the heartbeat travels down the left side of the heart. Psychotropic drugs can produce cardiovascular side effects associated with a degree of cardiotoxicity. However, with your family history and complaints of chest pain, I would recommend that you see a cardiologist for further evaluation. A bundle branch block (BBB) is a blockage or disruption to the electrical signal that causes your heart to beat. 5%) DBP >80–90 mmHg with increase of 10 mmHg Right bundle branch block comes from a problem with the heart’s ability to conduct electrical signals. Unmonitored toxicity can cause ventricular dyssynchrony or fatal arrhythmia. The Oct 10, 2020 · Right bundle branch block (RBBB) is frequently found in the general healthy population. Common in young Thai males. There are two types of second-degree heart block. Right bundle branch block may occur in other pathologies e. Possible causes include trauma, structural changes, infiltrative diseases (eg, sarcoidosis), myocarditis, and myocardial Can jra cause right bundle branch block s an adult? A doctor has provided 1 answer. During an electrocardiogram (ECG), sensors (electrodes) are attached to the chest and sometimes to the arms or legs. The delay or block can happen on the pathway that sends electrical impulses to either the left or right side of the ventricles. The 2 upper chambers are called atria, and the 2 lower chambers are called ventricles. Nov 16, 2023 · Did you know that certain medications can cause symptom of 'Bundle branch block right'. There are two main conducting pathways in the heart, the left and the right bundle. Anxiety can be considered one of the causes of some named conditions, such as high blood pressure; therefore, it can be indirectly linked to right bundle branch blockage. Widespread use of cocaine and its attendant toxicity has produced a wealth of benchwork studies and small animal investigations that evaluated the effects of cocaine on the cardiovascular system. That’s why there are two types of bundle branch blocks: Left bundle branch block. The main left bundle branch penetrates the membranous portion of the interventricular septum under the aortic ring and then divides into several fairly discrete branches. The coexistence of a heart disease complicates the management of mental illness, can contribute to a reduced quality of life and a worse illness course. On the other hand, a new right bundle branch block in patients with chest pain may indicate occlusion in the left anterior descending artery. 10 seconds in patients younger than 8 years) Prolonged Oct 3, 2023 · LBBB: Left Bundle Branch Block. right ventricular strain (especially due to pulmonary Mar 24, 2022 · The third degree is called complete heart block. Therefore, the AHA / ACCF / HRS recommendations for Mar 28, 2016 · Transient BBB can have several mechanisms including phase 3 block, phase 4 block and concealed conduction. 1% was found in the male population ≥52 years old. American Roentgen Ray Society Images of Right bundle branch block causes All Images X-rays Echo & Ultrasound CT Images MRI; Ongoing Trials at Clinical Trials. 5%) SBP >120 mmHg + increase of 10 mmHg 4/265 (1. This block leads to an abnormal heart rhythm. Assessing QT-interval in the presence of bundle-branch block. This results in the Jul 28, 2009 · Abstract. A LBBB can be caused by problems with the electrical conduction of the heart, the heart muscle, or the shape of the heart. Although LBBB is often associated with significant heart disease and is often the result of myocardial injury, strain or hypertrophy, it can also be seen in patients without Oct 31, 2013 · Complete right bundle branch block (± left anterior hemiblock) on ECG, present in 7 (2. The heart's electrical system is responsible for coordinating the timing of the heartbeats, ensuring that the chambers contract in a synchronized manner. Oct 16, 2022 · However, it can cause intermittent effects, including dizziness and even syncope (fainting). Jul 13, 2022 · Electrophysiology. The aim of this study was to perform a brief meta-analysis on the Oct 12, 2015 · The RBBB finding on your EKG is nonspecific and does not signify that you have heart disease. Just need to lose 30-40 lbs. Some people are born with heart block – known as congenital heart block. Possible causes include trauma, structural changes, infiltrative diseases (eg, sarcoidosis), myocarditis, and myocardial Skipped heartbeats and a slower-than-normal heart rate may result. QRS complex: QRS duration becomes prolonged. In clinical practice, differential diagnosis from other arrhythmic disorders is important. 001). Images. May 20, 2020 · Transthoracic echocardiography showed normal left ventricle ejection fraction (LVEF), and initial ECG demonstrated sinus bradycardia with high-grade atrioventricular block with likely atrioventricular Wenckebach and a right bundle branch block . The diagnosis is made clinically. The 2 lower chambers are called ventricles. 14 Among men 75 to 79 years old, right bundle-branch block was found in 4. Incomplete right bundle branch block is a common finding at all ages with more prevalence in men compared with women 1. 40% of patients have a family history of sudden death. The co-occurrence of psychiatric disorders in cardiac patients might affect the clinical Sep 19, 2020 · 3. T-wave: T-wave may diminish in amplitude. A diagnosis of left bundle branch block often means that you have an underlying heart condition. Acquired bundle branch block could be related to repetitive drug use. Associated with mutation of SCN5A gene, blocking Na Nov 4, 2019 · ECG performed 5 minutes after infusion of lidocaine 100 mg reveals junctional escape rhythm with right bundle branch block and left anterior fascicular block at a heart rate of 60 bpm. Jan 24, 2022 · Background. You are never too young to prevent heart disease, which can be prevented 85% of the time. Unmonitored toxicity can cause ventricular Psychotropic drugs can produce cardiovascular side effects associated with a degree of cardiotoxicity. Left bundle branch block may also develop following aortic valve disease or cardiac procedures. minor chest trauma. Electrical impulses that cause your heart to beat (contract) start in the heart's upper right chamber (right atrium) and travel to the lower chambers (ventricles). Your heart has 4 chambers. ECG performed at discharge: sinus rhythm, narrow QRS complex, and left anterior fascicular block. This system includes specialized pathways RBBB is a block at the right bundle branch leading to delayed right ventricle depolarization. Heart attack (myocardial infarction) High blood pressure (hypertension) Inflammation of the heart muscle (myocarditis) Jul 25, 2023 · Left bundle branch block (LBBB) is a common electrocardiographic (ECG) abnormality seen in patients whose normal cardiac conduction down both anterior and posterior left fascicles of the His-Purkinje system is compromised. Structurally normal heart. Mar 1, 2022 · Left bundle branch block is a problem with the heart’s electrical wiring (conduction) system. In a healthy heart, the electrical signal for your Nov 14, 2022 · Digitalis: This medication is commonly used to slow down the heart rate. 4-6 Furthermore, the FDA issued a safety announcement in Sep 19, 2020 · 3. The predictive significance of right bundle branch block was independent of age at enrollment, gender, ethnicity and risk factors for coronary artery disease. Patients have abnormal findings on the surface electrocardiogram (ECG) but do not usually have any apparent cardiac structural abnormalities. The R or r deflection is usually wider than the initial R wave. No symptoms in otherwise healthy 37 y/o male. 5%) SBP >140 mmHg 20/265 (7. A problem in the bundle of His presents in an identical fashion to a combined block of both bundles, ie, complete heart block. Patients with heart failure with reduced ejection fraction and left bundle branch block may respond positively to cardiac resynchronization Sep 19, 2020 · 3. Examples of medications that can affect the heart`s electrical conduction system include beta-blockers, calcium channel blockers, and antiarrhythmic agents. Brugada syndrome is a disorder characterized by sudden death associated with one of several ECG patterns characterized by incomplete right bundle-branch block and ST-segment elevations in the anterior precordial leads. May 13, 2020 · Bundle branch block is a heart block caused by a lesion in one of the bundle branches located in the septum (the heart muscle between the two ventricles). This delay does not often cause symptoms. An can show how well the heart is beating. However, a more common occurrence is an isolated left or right bundle branch block. Appropriate discordance (discussed below) Electrophysiology. In RBBB, the left ventricle is activated normally, thus the early part of the QRS complex correlating to septal depolarisation is unchanged. In most cases, it does not require any treatment and prognosis is better. BBB can affect your right ventricle (right bundle branch block), left ventricle (left bundle branch block) or both ventricles. infection in the heart tissue or valves. Despite this wealth of knowledge, very little is known about the frequency or types of arrhythmias in patients with significant cocaine A number of antipsychotic and antidepressant drugs are known to increase the risk of ventricular arrhythmias and sudden cardiac death. Such symptoms are more likely to occur if the bundle branch block exists along with a cardiovascular disease such as hypertension (high blood pressure), heart failure, or cardiomyopathy (disease of the heart muscle). Causes can include: Left bundle branch block. Bundle branch blocks: These happen when the electrical signals travel more slowly in one side of your heart than in the May 19, 2024 · Incomplete Right Bundle Branch Block. Review articles. Having a family history of Dec 29, 2020 · More specific findings, suggestive of right ventricular strain, were encountered in only one-third of patients. 6%) patients, predicted a higher risk of mortality (HR: 5. This happens when no signals reach your ventricles, the lower chambers of the heart. Your heart sends electrical impulses to the bottom chambers of your heart Sep 4, 2023 · Impulses, or electrical signals, travel through both the left and right chambers of your heart to make it pump. For all other types of atrioventricular block, in the absence of conditions associated with progressive atrioventricular Jun 21, 2019 · Right bundle branch block patterns with a normal duration of QRS complex are quite common in healthy people. In RBBB the right conducting pathway no longer functions so electrical conduction is maintained through the left bundle. Other potential causes of RBBB include: heart attack. Leads V1 or V2: rsr’ , rsR’ , or rSR’ pattern. Powerpoint slides. can certain medications cause bundle branch block?: BBB: Certaiin common blood pressure medications and/or antiarrhythmics. Bundle branch block is a type of conduction block involving partial or complete interruption of the flow of electrical impulses through the right or left bundle branches. ST segment: ST segment depression may develop. Therefore, the AHA / ACCF / HRS recommendations for Sep 27, 2022 · There is also evidence that HCQ usage may be associated with the development of conductive heart disorders, such as right bundle branch block, left anterior fascicular block, and complete atrioventricular (AV) block [18, 48]. 12 seconds in patients olderthan 12 years (> 1. It is defined by QRS complex duration between 110 and 120 ms in adults and a rsr', rsR', or rSR' pattern in leads V1 or V2 2, and it implies a partial block in the right Purkinje system. The clinical manifestations, evaluation, and . In normal cardiac conduction, impulses travel equally down the left and right Right bundle branch block (RBBB) is an abnormality of the electrical conducting system of the heart. g. Cardiovascular effects of hypothyroidism can include electrocardiographic changes, such as bradycardia, right bundle branch block, flattened or inverted T waves, QRS prolongation and even torsades de pointes ventricular arrhythmia []. However, the prognostic role of right bundle branch block (RBBB) in these patients has not yet been evaluated. 3; 95% CI: 2. Aug 8, 2023 · A right bundle branch block is typically caused by disease processes that change the myocardium of the right bundle branch, for example, structural changes, trauma, and infiltrative processes. The right part of the heart will have delayed signals, which will cause an irregular heartbeat. Widening of the QRS complex – in the setting of left bundle-branch block (LBBB) or right bundle-branch block (RBBB) – leads to QT-interval prolongation without significant alterations to the repolarization duration . Most cited articles. This quick and painless test measures the electrical activity of the heart. Right bundle branch block may indicate pathology in the right side of the heart e. qa gx jv sb pm qm cl vv nd ss