Bundle Branch Block: Types, Causes and Symptoms

Bundle branch block is the term for the condition when the heart cannot beat normally due to a delay or obstruction in the course of the electrical impulse. Periodically, the heart experiences greater difficulty pumping blood throughout the body.

The pathway that electrical impulses follow as they travel to the left or right ventricles of the heart could stop or get blocked.

The bundle branch block may not require treatment. When it occurs, treating the underlying medical condition such as heart disease that led to the bundle branch block is the main course of treatment.

Types of Bundle Branch Blocks 

Bundle branch bricks come in two varieties:

• Right bundle branch block (RBBB): The disorder known as right bundle branch block (RBBB) is caused by a break in the electrical pathway that connects your right ventricle to the external environment.
• Left bundle branch block (LBBB): A break in the electrical signaling pathway that supplies your left ventricle causes a left bundle branch block (LBBB).

Your left and right bundles may be impacted simultaneously, or one bundle may be affected.

Causes Of The Bundle Branch Block

Electrical impulses pass through the heart muscle, causing it to beat (contract). Both the left and the right bundles are branching on the path that these impulses take. If either of these branch bundles is damaged for example, following a heart attack the electrical impulses could get blocked. Unusual heartbeats are the outcome.

Multiple reasons can lead to bundle branch blocks, depending on whether the bundle branch on the left or right is affected. Unknown causes can occur occasionally.

Several reasons could be:

Left bundle branch block

• Angina, also known as a myocardial infarction
• Elevated blood pressure, or hypertension,
• Heart muscle inflammation, also known as myocarditis, can result in bigger, stiffer, or weaker heart muscle (cardiomyopathy).

Right bundle branch block

• Pulmonary embolism
• A heart attack, or myocardial infarction
• Heart structural problems that exist from birth are known as congenital heart defects. One such defect is an atrial septal defect, which is a hole in the wall that separates the upper chambers of the heart.
• Pulmonary hypertension
• An inflammation of the heart muscle is called myocarditis.

Symptoms Of The Bundle Branch Block

A bundle branch block may not exhibit any symptoms at all. When this illness's symptoms do manifest, they may include:

• Dizziness.
• Having a syncope episode.
• Feeling like one is about to faint (presyncope).

The following are possible signs of blockages in the bundle branches on both sides:

• Arrhythmia, which is an irregular heartbeat.
• Trouble breathing (dyspnea).
• Bradycardia

It is more probable that symptoms will manifest if you:

• An underlying heart condition.
• The left and right bundle branch blocks.
• Severe bundle branching block.

Risk Factors of The Bundle Branch Block

Risk factors for bundle branch block include the following:

Getting older: Bundle branch block is more common in older adults than in younger adults due to underlying medical conditions. Heart disease and elevated blood pressure both raise the chance of bundle branch block.

Treatment Of The Bundle Branch Block

Most people who have bundle branch blocks are asymptomatic and do not need medical care. For example, there's no medication for treating the left bundle branch block. The specific symptoms and underlying heart problems, however, will determine the course of treatment.

Medicines

Drugs to reduce blood pressure or decrease heart failure symptoms are possible treatments for cardiac problems caused by bundle branch blocks.

Surgery and other procedures

Your doctor might recommend a pacemaker if you have a bundle branch block and a history of fainting. A tiny implanted device called a pacemaker is positioned under the skin of the upper chest. It is attached by two cables to the right side of the heart. When required, the pacemaker produces electrical impulses to maintain a regular heartbeat.

Biventricular pacing, sometimes referred to as cardiac resynchronization therapy, may be necessary if you have a bundle branch block and poor heart pumping capacity. There are parallels between pacemaker placement and this therapy. 

There will be a third wire linked to the left side of your heart to make sure that both sides are beating simultaneously. Improving the heart's chamber contractions' efficiency and order is the goal of cardiac resynchronization therapy.

Prevention Of The Bundle Branch Block

Your risk of BBB and other heart problems can be decreased by taking good care of yourself and making sensible decisions. These comprise:

• Eat less fat in your diet.
• Do aerobic exercises regularly.
• Maintain an appropriate weight.
• Regulate your cholesterol.
• Stop smoking and using items made of tobacco.
• Reduce your blood pressure if it's high.
• For routine exams, visit your doctor.

Complications Of The Bundle Branch Block

If both the left and right bundles are blocked, the main problem is a complete blockage of the electric signaling from the upper to the lower chambers of the heart. Insufficient signaling could cause the heart rhythm to slow down. A lower heart rate might lead to serious consequences like fainting and irregular heartbeats.

Because bundle branch block affects the heart's electrical activity, it can often make it more challenging to diagnose other cardiac conditions, especially heart attacks. It could lead to delays in receiving appropriate treatment for different types of cardiac diseases.

Diagnosis Of The Bundle Branch Block

If you have the right bundle branch block and are in good general health, you might not need a full medical check. A thorough medical checkup is necessary if you have a left bundle branch block.

The reasons behind a bundle branch block can be found using the tests listed below:

• Cardiogram is sometimes referred to as an ECG or EKG: During an electrocardiogram (ECG), electrodes, or sensors, are attached to the chest and sometimes the arms or legs. And can show the rhythm of the heart. It may also show signs of a bundle branch block and the side of the heart that is injured.
• Echocardiogram: Using sound waves, this examination produces finely detailed images of the heart and heart valves. It can show the cardiac muscle's thickness and anatomical structure. Your supplier may utilize this test to pinpoint the precise reason for the bundle branch block.

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