Association of reperfusion delay with inflammatory markers and coronary flow impairment assessed by corrected TIMI frame count in STEMI patients undergoing primary PCI: a cohort study

Abstract

Background: Timely reperfusion remains central to the management of ST-segment elevation myocardial infarction (STEMI). In addition to limiting infarct size, delays in reperfusion may intensify systemic inflammation and contribute to impaired coronary microvascular flow, even when epicardial recanalization appears angiographically successful. This study examined whether reperfusion delay is associated with inflammatory markers at admission and impaired coronary flow measured by corrected TIMI frame count (CTFC) in patients with STEMI treated with primary PCI. Methods: We conducted a single-center observational cohort study including 104 consecutive patients with STEMI who underwent primary percutaneous coronary intervention (PPCI).Reperfusion delay was defined as symptom-to-balloon time and was grouped into four categories (< 2, 2-4, 4-6, and > 6 hours). Inflammatory markers, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), were measured at admission and after PPCI. Coronaryflow was quantitatively assessed usingthe corrected TIMI frame count (CTFC). Associations between reperfusion delay, inflammatory markers, and CTFC were evaluated. Results: CTFC values increased progressively with longer reperfusion delay, indicating worsening coronary flow (P < 0.05). Admission ESR increased significantly with longer symptom-to-balloon time (P < 0.05), and higher CRP categories were more frequently observed among patients with delayed reperfusion (P < 0.05). Higher ESR and CRP levels at admission were also associated with increased CTFC values. Post-procedural ESR and CRP levels, however, showed no significant association with re-perfusion delay or CTFC (P > 0.05). Higher ESR and CRP levels at admission were also linked with increased CTFC values. Post-procedural ESR and CRP levels, however, showed no significant association with reperfusion delay or CTFC. Conclusions: In patients with STEMI undergoing primary PCI, delayed reperfusion is associated with increased inflammatory burden at presentation and impaired coronary flow as assessed by corrected TIMI frame count. Taken together, these findings suggest that inflammatory activation during prolonged ischemia may contribute to impaired coronary flow and highlight the continued importance of minimizing reperfusion delay.