Determination of the relationship between TIMI myocardial perfusion grade and ST resolution in evaluating the coronary reperfusion after primary PCI

Introduction: Review of conducted research suggests some evidence on the relationship between TIMI flow grade related to myocardial perfusion and segment resolution rate (STR), while this evidence is limited. Thus, the current research was conducted and implemented to evaluate the relationship between TIMI grade and STR after PCI.Methodology: by reviewing the medical record of ۱۱۲ patients with diagnosis of acute coronary syndrome and under coronary angiography, the primary characteristics of the patients were extracted in this research. Coronary flow was evaluated after PCI by ۲۰۰ μg nitroglycerin bolus intracoronary prescribing. TIMI value was determined based on the contrast opacification dynamics of coronary microcirculation. ECG bands were evaluated in two stages of before PCI and ۳۰ minutes after transferring of patient to intensive care unit (ICU). By aggregating the total values in increase in ST in all infarction leads and reduction in reciprocal leads, SSTD value was determined. Relative SSTD value, which means percentage of reduction in SSTD (SSTD%) compared to its base value, was calculated. Findings: strong and significant correlation was found between TIMI variations after PCI and SSTD (correlation coefficient=۰.۳۴۰, P = ۰.۰۰۱). Additionally, a strong and significant correlation was found between TIMI variations after PCI and SSTD% (correlation coefficient =۰.۴۴۲, P = ۰.۰۰۱). Based on the analysis of area under the ROC curve, evaluation of SSTD (AUC = ۰.۶۹۹) and SSTD% (AUC = ۰.۶۲۱) could predict improvement in TIMI flow in patients after PCI. The mean SSTD in patients who finally died and living patients was ۹.۵۷ ± ۹.۸۸ and ۱۷.۴۰ ± ۱۰.۷۱, respectively, which it was significantly lower in patients who died (P value = ۰.۰۰۲). Additionally, mean SSTD% in patients who died and living patients was ۳۷.۲۳ ± ۲۶.۲۹ and ۵۷.۱۰ ± ۱۷.۹۷, respectively, which it was significantly lower in patients who died (P = ۰.۰۰۱ ). According to the analysis of area under ROC curve, evaluation of SSTD (AUC = ۰.۶۶۷) and SSTD% (AUC = ۰.۸۷۳) could predict the occurrence of mortality in patients after PCI. Conclusion: measuring STR can predict TIMI grade variations strongly after performing the PCI process. In addition, determining STR has great value in predicting the mortality after the mentioned procedure.

Keywords:

TIMI myocardial perfusion , ST resolution , coronary reperfusion , primary PCI