Comparison of no-reflow phenomenon in patients with ST-segment- elevation myocardial infarction undergoing primary PCI vs. pharmaco-invasive strategy: a single-centre study

Background The no-reflow phenomenon after percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI) represents a major barrier to successful reperfusion, leading to adverse outcomes despite epicardial vessel patency. Comparative evidence regarding its incidence and clinical consequences between primary PCI and pharmaco-invasive PCI remains scarce. Aim The study aimed to compare the incidence of the no-reflow phenomenon in patients undergoing pharmaco-invasive PCI versus primary PCI, and to evaluate the short-term clinical outcomes of patients with no-reflow at three months post-procedure. Methods In this prospective, single centre, observational study, STEMI patients presenting within 24 h of symptom onset were enrolled at a tertiary care centre. Patients experiencing no-reflow were categorized into Group A (primary PCI; n = 92) and Group B (pharmaco-invasive PCI; n = 192). Baseline demographics, comorbidities, angiographic characteristics, and outcomes were analysed. The primary outcome was the incidence of major adverse cardiac events at three months. Results Among 857 patients undergoing primary PCI and 2,976 undergoing pharmaco-invasive PCI, the incidence of no-reflow was significantly higher in the primary PCI group (10.7% vs. 6.5%). Patients in Group A were older (58.9 ± 13.6 vs. 54.4 ± 11.4 years; P = 0.004) and more frequently diabetic (55.4% vs. 41.6%; P = 0.029), whereas hypertension was more prevalent in Group B (42.7% vs. 13.0%; P < 0.001). Baseline TIMI 0 flow was more common in Group A (79.3% vs. 24.5%; P < 0.001). After PCI, final TIMI 3 flow rates were comparable (85.9% vs. 89.6%; P = 0.361). In-hospital complications and three-month outcomes were similar between two groups: death (4.3% vs. 5.2%), revascularization (4.3% vs. 4.7%), and rehospitalization (5.4% vs. 3.1%) (all P > 0.05). Conclusion No-reflow was more frequent after primary PCI, particularly in older, diabetic, and late-presenting patients with baseline TIMI 0 flow. Both reperfusion strategies achieved comparable short-term clinical outcomes in no-reflow patients. Pharmaco-invasive PCI may mitigate the risk of no-reflow in selected STEMI patients while maintaining equivalent early prognosis.