What ST segment findings are commonly associated with angina?

The commonly associated ST segment finding with angina is horizontal or down sloping ST segment depression. This finding indicates that there is myocardial ischemia, which occurs when there is a temporary reduction in blood flow to the heart muscle during conditions like angina.

In angina, the heart muscle does not receive enough oxygen during periods of increased demand (such as with exercise or stress), leading to these characteristic changes on an electrocardiogram (ECG). The horizontal or down sloping ST segment depression signifies that there is a delay in the repolarization of the cardiac tissue due to the imbalance between oxygen supply and demand.

Other changes, like ST segment elevation, would suggest more severe conditions such as an acute myocardial infarction rather than the transient ischemic episodes seen in angina. A flat ST segment does not indicate any significant ischemic activity, and an upright ST segment typically signifies a normal repolarization process, thus not aligning with the diagnostic criteria for angina.