Prevalence and prognostic implications of the no-reflow phenomenon in patients undergoing primary percutaneous coronary intervention in a university center in a middle-income country

Background No-reflow (TIMI flow ≤2) during primary PCI for STEMI occurs in 7–25% of cases, indicates poor myocardial tissue perfusion, and is associated with a poor outcome. (1–3) The incidence in our hospital is unknow. Purpose To analyse the prevalence of no-reflow and the 30-day mortality in our hospital. Methods We analysed the database of a teaching hospital and identified 2463 patients who underwent primary PCI from January 2006 to December 2021. No-reflow was defined as post-PCI TIMI flow ≤2, in the absence of post-procedural significant (≥25%) residual stenosis, abrupt vessel closure, dissection, perforation, thrombus of the original target lesion, or epicardial spasm. The outcome measure was 30-day mortality. Results Of total of 2050 patients, no-reflow phenomenon was found in 413 (16.8%) patients, and it was associated with significantly higher 30-day mortality (16.7% vs. 4.29%; p = <0.001). Patients with no-reflow were older (60 [53–69.5] vs. 59 [51–66]; p=0.001), with a higher delay in onset of symptom to emergency department arrival (270 min vs. 247 min; p=0.001) but had similar door to balloon time (75 min vs. 80 min; p=0.434). No-reflow patients also had had fewer previous myocardial infarction (11.6 vs. 18.4; p=0.001), lower systolic blood pressure (128 mm Hg vs. 132 mm Hg; p = <0.001) and a Killip class >1 (37% vs. 26.4%; p = <0.001). No-reflow patients were more likely to have an anterior myocardial infarction (55.4% vs. 47.8; p=0.005), initial TIMI flow 0 (76% vs. 68%; p = <0.001) and TMP 0 (14.1% vs. 4.5%; p = <0.001). Conclusion No-reflow occurred in 16.8% of STEMI patients undergoing primary PCI and was more likely with older age, delayed presentation, anterior myocardial infarction and Killip class >1. No-reflow was associated with a higher mortality at 30-day follow-up.