Right bundle branch block (RBBB) is an abnormal pattern that can be seen on an electrocardiogram (ECG) that indicates that the electrical impulse from the heart is not distributed normally through the ventricles. In particular, a right bundle branch block means that electrical stimulation of the right ventricle is delayed.
The two branches of the bundle (right and left) are electrical pathways that allow the cardiac electrical impulse to travel rapidly and evenly through both ventricles so that the heartbeat is well coordinated.
With right bundle branch block, there is a partial or complete block of the electrical impulse to the right ventricle, which delays its electrical activation and, consequently, its contraction.
Similar to left bundle branch block (LBBB), in which pacing of the left ventricle is delayed), right bundle branch block affects how efficiently the heart can pump blood. Since the right side of the heart carries blood to the lungs and not to the entire body, RBBB carries a lower risk of death than RBBB.
A right bundle branch block is sometimes associated with underlying heart or lung disease. When a right bundle branch block is diagnosed, a medical examination is generally required to identify and reduce cardiovascular risks.
A right bundle branch block causes characteristic ECG changes, so doctors can usually easily diagnose this condition just by looking at the results.
In bundle branch block , the QRS complex, the part of the ECG that represents the electrical impulse that travels through the ventricles, is wider than usual because it takes longer than usual to distribute it.
With right bundle branch block, there is a characteristic pattern of this 12-lead expansion (or "views") provided by a standard ECG. Therefore, it is usually easy to determine the presence of a right bundle branch block simply by observing the nature of the expansion of the QRS complex.
Sometimes a right bundle branch block is part of Brugada syndrome . If an ECG in a young person shows a pattern indicating a right bundle branch block with ST elevation in leads V1 and V2, especially if there is a history of unexplained episodes of fainting or dizziness, consider Brugada syndrome. as an opportunity.
The incidence of right bundle branch block increases with age. The disease occurs in people over 65 years of age twice as often as in people over 40 and is more common in men.
Right bundle branch block is more common than left bundle branch block and can be less serious. However, a right bundle branch block indicates an increased risk of heart disease and ultimately the need for a pacemaker.
If a right bundle branch block is detected, it can be classified as complete or incomplete block based on ECG data. An incomplete block means that electrical signals are transmitted better than a complete block.
Since an incomplete block can sometimes turn into a complete block, continuous monitoring is recommended. However, an incomplete block is usually not dangerous on its own.
Underlying heart and lung disease
The right branch of the bundle of His, which passes through the interior of the right ventricular muscle, is relatively superficial in relation to the surface of the ventricular cavity. This makes the right bundle branch vulnerable to injury and stretching as long as the right ventricle is subjected to any type of stress.
Right bundle branch block often occurs with any right ventricular disease. These conditions can include:
A right bundle branch block can also occur in any condition that increases right ventricular pressure.
This is more common with pulmonary embolism , but lung conditions are also troublesome, causing chronic increases in right ventricular pressure. Conditions like chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea, for example, can cause pulmonary hypertension , which can lead to a right bundle branch block.
Anyone who has a right bundle branch block needs a medical exam for signs of heart or lung disease. A chest X-ray and an echocardiogram are commonly used for this purpose.
Because the right bundle branch is susceptible to anything that can cause even minor trauma to the right ventricle, temporary right bundle branch block sometimes occurs in patients undergoing cardiac catheterization . This temporary event occurs when the catheter irritates the right bundle branch. It usually goes away quickly (within minutes) after the catheter is removed.
However, in people who already have a left bundle branch block, even this temporary right bundle branch block is likely to result in a temporary complete heart block and the heart may stop beating. Therefore, in patients with right-sided cardiac catheterization, a temporary pacemaker is sometimes inserted during the procedure to ensure that the heart rate continues uninterrupted during the examination.
With a block of the right or left bundle of His, two ventricles of the heart are paced sequentially (one after the other) and not simultaneously. This loss of normal coordination between the two ventricles can reduce the efficiency of the heartbeat.
However, the decrease in cardiac efficiency is probably less important in right bundle branch block. For example, the use of cardiac resynchronization therapy (CRT) may not be as beneficial for people with right bundle branch block, even if they have heart failure.
By itself, right bundle branch block does not require permanent pacemaker therapy. However, in some people, a right bundle branch block is just one manifestation of a more general problem with the electrical conduction system of the heart.
In such cases, a pacemaker may be necessary if sick sinus syndrome or heart block develops.
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A right bundle branch block, even in people without heart disease, indicates an increased risk of cardiovascular disease. Anyone diagnosed with this condition should be screened to rule out an underlying heart or lung condition and to minimize cardiovascular risk factors that they can control.
A right bundle branch block is especially serious in people with heart failure or heart attack.
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