What are the classical signs of a myocardial infarction on an ECG?

• A. ST elevation, Q waves, and T wave inversions
• B. Deep Q waves and flattened T waves
• C. Normal ST segments with aberrant QRS complexes
• D. J point elevation only

Answer: (A)

The classical signs of a myocardial infarction on an ECG include ST elevation, Q waves, and T wave inversions.

ST elevation occurs in the early stages of an acute myocardial infarction, particularly in a STEMI (ST-Elevation Myocardial Infarction). This elevation signals that there is a significant blockage in the coronary arteries, leading to a lack of blood supply to the heart muscle. The development of pathological Q waves indicates that there has been myocardial necrosis or damage, which typically manifests in the leads that correspond to the area of infarction. T wave inversions may follow as the heart muscle begins to recover, reflecting changes in the repolarization phase of the cardiac cycle due to the injured myocardium.

Understanding these patterns is crucial for timely intervention, as they guide healthcare providers in diagnosing myocardial infarction and determining the urgency and type of treatment required.