What is one of the common causes of ischemic changes observed on an ECG?

• A. Coronary artery disease
• B. Myocardial infarction
• C. Congestive heart failure
• D. Cardiac arrest

Answer: (A)

Coronary artery disease (CAD) is a primary underlying cause of ischemic changes observed on an ECG. This condition occurs when the coronary arteries become narrowed or blocked due to atherosclerosis, which reduces blood flow to the heart muscle. When the heart muscle does not receive adequate blood supply, it can lead to ischemia, characterized on the ECG by changes such as ST segment depression or elevation, T wave inversions, or the presence of Q waves.

While myocardial infarction is a consequence of ischemic changes and presents its own set of distinct findings on an ECG, CAD is the underlying process that often leads to those ischemic changes. Congestive heart failure and cardiac arrest can have various ECG findings, but they are not direct causes of ischemia in the same way as CAD, making coronary artery disease the most common cause of ischemic changes seen on an ECG.