Left bundle branch block

Updated: 2024-07-13

Description

A delay or blockage of electrical signals to the left side of the heart.

Overview

Left bundle branch block sometimes makes it harder for the heart to pump blood to the rest of the body. High blood pressure, a heart attack, and thickening, stiffness or irritation of the heart muscle can cause it.

Symptoms

Most people don't have symptoms. If they occur, they include fainting or a slow heart rate.

Treatments

Treatment depends on the cause. Any underlying condition, such as heart disease, should be treated. Some people need a device called a pacemaker to help the heart beat.