Association between clinical parameters and ST-segment resolution after primary percutaneous coronary intervention in patients with acute ST-segment elevation myocardial infarction.

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate and compare various parameters between complete and incomplete ST-segment resolution (STR) patients' groups and to identify associates of STR in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PPCI) (primary outcome).

MATERIALS AND METHODS: A total of 203 consecutive patients were divided into two groups according to the degree of STR: <70% (incomplete) and ≥70% (complete resolution) 5-15min after the PPCI. The cardiovascular risk factors, sex, Killip class, Thrombolysis in Myocardial Infarction (TIMI) flow, symptom-onset-to-balloon time and door-to-balloon time, and adverse cardiovascular events (secondary outcome) were assessed and compared between two groups.

RESULTS: There were 147 patients with incomplete STR and 56 patients with complete STR. Patients with complete STR were younger, had lower Killip class, shorter duration of the chest pain and were less likely to have anterior myocardial infarction (AMI). Patients in the incomplete STR group had longer symptom-onset-to-balloon and door-to-balloon intervals. TIMI3 flow after PPCI was more common in the complete STR group. TIMI flow ≤2 after PCI, AMI and symptom onset-to-balloon time were inversely associated with STR (beta coefficients -28.635, -28.611, and -0.917, respectively). AMI (OR=29.9), symptom onset-to-balloon time (OR=1.7) and patient's age (OR=1.1) were associated with an increased likelihood of having incomplete STR.

CONCLUSIONS: Patients with complete STR were younger, had lower Killip class, shorter duration of STEMI, were less likely to have AMI, were more likely to recover TIMI3 flow. Age, TIMI-flow grade 2 or less after PPCI, AMI and symptom-onset-to-balloon time were associated with STR.