ST segment elevation during dobutamine stress echocardiography after acute myocardial infarction: Clinical significance and correlation with contractile recovery

The aim of this study was the evaluation of the value of dobutamine stress induced ST-segment elevation after acute myocardial infarction in predicting spontaneous contractile recovery. Fifty eight consecutive patients were studied within 7 days after first acute myocardial infarction (AMI) with dobutamine stress echocardiography (DSE). A score model based on 16 segments and four grades was used to assess the left ventricular function and a twelve-lead electrocardiography was continuously monitored throughout the test. Follow up was performed by trans-thoracic echocardiography at 90 days. At follow up, contractile recovery was defined as improvement of wall motion score by more than one grade in at least two myocardial segments. ST-segment elevation was observed in 24 (41%) out of the 58 patients studied. During DSE; persistent segmental wall motion abnormalities were more frequently observed in patients without ST-segment elevation while improvement without subsequent worsening was more frequently observed in patients with ST-segment elevation (P = 0.001). On follow up, contractile recovery was reported in 37 (64%) patients, it was more frequently observed in patients who already developed ST-segment elevation during DSE (P = 0.007). Dobutamine induced ST-Segment elevation has the sensitivity, specificity, positive and negative predictive values of 66%, 86%, 88% and 53%, respectively to predict spontaneous contractile recovery after AMI, while the combined sensitivity, specificity, positive and negative predictive values of dobutamine echocardiography and electrocardiography were 73%, 89%, 94% and 64%, respectively. Dobutamine stress induced ST segment elevation occurring in electrocardiographic leads exploring an infarct area is a predictor of spontaneous contractile recovery after AMI particularly when combined with echocardiogarphic evidence of myocardial viability.