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
| Cause | ST Elevation Site | Reciprocal Changes |
| STEMI | Coronary artery distribution | Common |
| Pericarditis | Diffuse | In AVR not AVL |
| BER | Chest leads | In AVR in 50% |
| Brugada syndrome | V1 and V2 | No |
| Ventricular aneurysm | Mostly anterior | No |
Learning bite
Territorial ST Segment elevation make AMI more likely; more diffuse ST Segment changes are typical of pericarditis.