What EKG Results Reveal About Your Heart Health

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Electrocardiogram (EKG) tests help doctors identify and diagnose present or past heart abnormalities. For those with a history of heart disease or anyone over 40, they are an important part of any doctor visit. Electrodes attached to strategic locations on the patient’s body measure the heart’s electrical impulses which are displayed on a computer monitor and then printed. Physicians then take the resulting data to interpret the health of the heart in an effort to identify and circumvent heart disease.

The patient’s EKG reading is compared to that of a normal heart. Differences in heart rate and the rhythm of contractions between the two readings highlight potential or past heart attacks, coronary artery diseases or heart disease. If these symptoms are detected, further testing is done to investigate.

Interpretation of the Signals and What They Mean

Interpreting the results can be done in a variety of ways, but most focus on identifying recurring patterns that may indicate trouble. The first thing EKG readers look at is the heart rate, as electrodes cause spikes in the graph by stimulating the heart into contracting and expanding. The “P” spike is the first spike that indicates the activity in the heart’s upper chamber. The PR interval, a horizontal line, indicates the bridge between the contraction and relaxation of the atria. Each EKG is made up of a series of these dips and spikes that represent the patterns of the heart’s impulses in the upper chamber. Each spike is represented by a different letter.

Each electrical signal starts in the sinus node or sinoatrial (SA) node, a group of cells located in the heart. The SA node is located in the upper right chamber of the heart. A healthy heart at rest normally fires off an electrical signal to indicate a new heart beat anywhere from 60 to 100 times a minute.

Following the SA node, the signal then travels to the right and left atria. The atria then contracts and pumps blood into the heart’s two lower chambers, the ventricles. The EKG records this data as the P wave.

The signal then passes between the atria and the ventricles through a group of cells known as the atrioventricular (AV) node. The signal generally slows down as it passes through the AV node, which allows the ventricles time to fill up with the life-sustaining blood. This is the flat line between the end of the P wave and the beginning of the Q wave on the EKG.

The electrical signal then leaves the AV node to travel into the right and left branches, recorded as the Q wave on the EKG.

As the signal spreads across the left and right ventricles, they contract to pump blood through the lungs and throughout the body. On the EKG, R marks the contraction of the left ventricle while S marks the contraction of the right. When the ventricles relax, this is shown as the T wave on the EKG.

A Living Graph

The entire process continues over and over again with each heartbeat. The EKG serves as a continually living graph to showcase the flow of blood through your heart and highlight any discrepancies. Most interpretations of the EKG are based on recurring patterns. Heart rate is generally the first thing a physician will consider when looking at the results. The electrodes cause spikes in the graphs to represent the contraction and relaxation of the heart muscles.

Follow Up After EKG

Normal hearts display a spike pattern known as sinus arrhythmia, which varies slightly from heart to heart. If the EKG does not display the sinus arrhythmia, it may be a sign of serious heart problems and may indicate the future occurrence of sudden heart failure. In these cases, patients are usually recommended to additional treatment to stave off heart attacks, though the exact treatment is left up to the physician.