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What is Congenital heart block

Congenital heart block is a rare complication of pregnancy associated with Sjögren Syndrome (an autoimmune syndrome) that may result in the death of the fetus or infant, or the need for pacing in the newborn or at a later stage. Doctors might detect congenital heart block before or after a baby is born. Certain diseases that may occur during pregnancy can cause heart block in a baby. Heart block is a problem that occurs with the heart’s electrical system. This system controls the rate and rhythm of heartbeats. (“Rate” refers to the number of times your heart beats per minute. “Rhythm” refers to the pattern of regular or irregular pulses produced as the heart beats.) With each heartbeat, an electrical signal spreads across the heart from the upper to the lower chambers. As it travels, the signal causes the heart to contract and pump blood. Heart block occurs if the electrical signal is slowed or disrupted as it moves through the heart.

Congenital heart block is a rare condition that affects the heart’s electrical system, which controls and coordinates its pumping function. In infants affected by this condition, the electrical signal that spreads across the heart and causes it to contract and pump blood, is slowed or completely interrupted. This can interfere with the heart’s normal rate and rhythm and may significantly limit the ability of the heart to pump blood to the rest of the body. Congenital heart block generally develops between 18 and 33 weeks of pregnancy. The underlying cause of the condition is poorly understood. However, mothers with lupus or another autoimmune diseases and parents with congenital heart disorders have an increased risk of having a child with a congenital heart block. The condition is generally treated with a pacemaker. Some cases may benefit from prenatal administration of steroids.[1][2]

This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).

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