RESUMO
The significance of reciprocal changes distribution in acute pericarditis has not been studied yet. We evaluated the significance of reciprocal changes distribution in leads V1 and AVR in differentiating acute pericarditis from myocardial infarction. A retrospective case control study done on 240 pateitns with AP only 76 patients who had ST elevation ECG changes were included in the study, compared to another control group of 80 patients with documented acute myocardial infarction [AMI]. The reciprocal changes in leads AVR and V1 +/- III was the most sensitive and specific ECG findings for the diagnosis of AP, sensitivity of 68% and specificity of 98% P< 0.001. Moreover PR segment depression P< 0.26, ST/T wave ratio P< 0.33, shape of ST segment P= 0.49, ST segment axis P- 0.11, were not found to be sensitive nor specific for the diagnosis of AP. However the diffuse ST segment elevation was suggestive of AP with sensitivity of 51% and specificity of 97.5%, P< 0.001. This study showed that the reciprocal changes in the leads V1, AVR, +/- leads III are more sensitive and specific than the PR segment depression, ST segment shape, ST/T wave ratio, ST segment axis. For the diagnosis of AP, and it can be useful tool to differentiate AP from AMI