Myocardial bridge

Overview

A myocardial bridge is a heart condition that is present at birth. That means it is a congenital heart defect. In this condition, a part of a heart artery travels through the heart muscle instead of over it. The band of heart muscle that covers the artery is called the myocardial bridge. You also may hear this condition called myocardial bridging or a coronary artery anomaly. Coronary means related to the heart's blood vessels.

A myocardial bridge can happen in any heart artery. But it usually affects the artery that supplies blood to a large part of the heart muscle. This artery is called the left anterior descending (LAD) artery. The middle part of the LAD artery is a common location for a myocardial bridge.

Usually a myocardial bridge doesn't cause any symptoms or heart issues and may not need treatment. The condition is often found by chance when heart imaging tests are done for another reason.

In some people with myocardial bridges, the heart muscle squeezes the artery enough to reduce blood flow. This may cause symptoms such as chest pain, shortness of breath or irregular heartbeats. Treatment usually begins with medicines. Sometimes a procedure or surgery is needed.

Symptoms

Most people with myocardial bridges have no symptoms. Some people don't notice symptoms until later in life. When symptoms occur, they often do so during exercise or other situations that make the heart beat faster and work harder.

Symptoms of a myocardial bridge may include:

• Chest pain or pressure, also called angina.
• Shortness of breath.
• A fast or pounding heartbeat, called heart palpitations.
• Dizziness or lightheadedness.
• Fainting, also called syncope.

Sometimes these symptoms may have another cause. Your healthcare professional may do tests to see whether a myocardial bridge or another health condition is causing your symptoms.

When to seek care

Make an appointment to see your healthcare professional if you have any symptoms that worry you. If symptoms happen during exercise, talk with your healthcare professional about what activity you were doing and how strenuous it was.

When to seek emergency care

Get emergency medical help if you have shortness of breath or chest pain that is sudden or that you cannot explain. Always call 911 or your local emergency number if you think your chest pain may be due to a heart attack.

Causes

A myocardial bridge forms before birth. It happens when part of a heart artery grows inside the heart muscle instead of on the heart's surface. The changed artery is considered a congenital coronary artery anomaly. This means the change in the path the artery takes is present from birth.

Risk factors

There are no known risk factors for a myocardial bridge.

Myocardial bridging happens more often in people with some heart conditions. For example, it is more common in people with hypertrophic cardiomyopathy, a disease in which the heart muscle becomes thickened.

Complications

Most often, a myocardial bridge does not cause complications. Rare or serious issues associated with myocardial bridging can include:

• Irregular heartbeats, called arrhythmias.
• Heart attack, also called myocardial infarction.
• Coronary artery spasm.
• Stress cardiomyopathy.
• Sudden cardiac death.

Prevention

There is no known way to prevent a myocardial bridge because it is present from birth.