Predictors of ST Depression Resolution in STEMI Patients Undergoing Primary PCI and Its Clinical Significance

Purpose: ST depression resolution (STD-R) in ECG is a prognostic factor indicative of successful fibrinolysis or angioplasty in the treatment of ST elevation myocardial infarction (STEMI) and subsequent mortality. We conducted this study to determine the clinical significance of STD-R and its predictors in patients with anterior STEMI undergoing primary percutaneous intervention (PPCI). Methods: Admission documents of all patients with diagnosis of anterior STEMI who were admitted to a specialty heart center and underwent PPCI since July 2018 until July 2019 were examined. The amount of ST elevation and depression in all 12 leads of a standard ECG at admission and 90 minutes after PPCI was measured and resolution was determined. All patients were followed-up for 10.8 +/- 4.0 months. Results: A total of 179 patients had ST depression besides elevation in the first ECG. Female gender, diabetes, not smoking, lower hemoglobin, and higher platelet counts were significantly more common in the group with less than 50% resolution of ST depression. STD-R <50% was significantly associated with the incidence of in-hospital acute heart failure and major adverse cardiac events (MACE) (p value: 0.025 and 0.012, respectively) and resolution of ST elevation >= 50% was associated with reduced in-hospital mortality (p value <0.0001). According to Kaplan-Meier curve, survival in the two groups of STE-R >= 50% and STE-R <50% was significantly different (Log rank: 31.18, p value<0.0001). Conclusion: STD-R can be considered to have high predictive power, like STE-R for predicting incidence of in-hospital acute heart failure and major adverse cardiac events.