ST Segment Distribution

ST segment elevation due to STEMI follows a coronary artery ‘territorial’ distribution which is not typically seen in other conditions.

It may also be accompanied by reciprocal changes (seen in 70% of inferior and 30% of anterior STEMI) [6].

The image displays ST segment changes of STEMI (with reciprocal changes) in a distribution clearly reflecting coronary artery territory (click on the ECG to enlarge).

ST segment elevation due to BER is typically evident in the precordial leads:

  • 74% in V1-V2
  • 73% in V3-V4
  • 37% in inferior leads [8]

ST Segment elevation is more diffuse in pericarditis.

For the distribution of ST Segment changes and associations with cause see Table 1.

Table 1

Table 1: Distribution of ST Segment changes


ST Elevation Site

Reciprocal Changes


Coronary artery distribution




In AVR not AVL


Chest leads

In AVR in 50%

Brugada syndrome

V1 and V2


Ventricular aneurysm

Mostly anterior


Learning bite

Territorial ST Segment elevation make AMI more likely; more diffuse ST Segment changes are typical of pericarditis.