What Causes an Abnormal EKG?

Different heart conditions and problems can cause abnormal EKG readings, including congenital heart defects, an enlarged heart, poor blood supply flowing to the heart and arrhythmia, according to MedlinePlus. An EKG, or ECG, is also known as an electrocardiogram.

Other conditions that may be indicated by an abnormal EKG include damage to the heart muscle, low electrolytes in the blood, fluid near the heart and myocarditis, MedlinePlus states. These conditions can be indicative of serious heart problems, including heart attack, tachycardia, sick sinus syndrome and Wolff-Parkinson-White syndrome.

An EKG test is typically administered when there is cause for concern. Those in a normal state of health do not have a yearly EKG, for example. This test is administered when a person complains of chest pains or other problems where an issue with the heart may be indicated, according to MedlinePlus. When a doctor performs the test, individuals lie flat on the backs, and electrodes are attached to their arms, legs, and chests. These electrodes are hooked up to the EKG machine, which gives the doctor a printout. From this printout, the doctor can determine if heart problems are present. An EKG measures the size of the heart chambers, how fast the heart is beating and any current or past damage to the heart.