An electrocardiogram or ECG can be an effective tool in the evaluation of a possible heart attack.

How an ECG Works
An electrical impulse stimulates the muscle fibers in the heart to contract. The impulse spreads through the heart in a very organized manner. The heart's normal electrical impulse has a characteristic pattern. The EKG machine displays the pattern of the electrical impulse.

Abnormal electrical patterns on the EKG can help identify heart disease.

The EKG can identify:

• Heart injury:
• Consistent with low oxygen to the heart
• Damage due to heart attack
• Enlargement of the heart
• Cardiac arrhythmia:
• Abnormal heartbeats or rhythms
• Abnormal electrical activity in the heart