Post-procedural TIMI flow grade 2 is not associated with improved prognosis in patients with non-ST-segment elevation myocardial infarction undergoing percutaneous coronary revascularization (PL-ACS registry)

Background: The impact of final Thrombolysis in Myocardial Infarction (TIMI) flow in the infarct-related artery (IRA) on outcomes in non-ST-segment elevation myocardial infarction (NSTEMI) patients treated with percutaneous coronary intervention (PCI) is unknown. This study aimed to evaluate the impact of post-procedural TIMI flow in IRA on outcomes in NSTEMI patients undergoing percutaneous coronary revascularization. Methods: We analyzed 2,767 patients with first NSTEMI from the Polish Registry of Acute Coronary Syndromes (PL-ACS) who underwent PCI. The patients were divided according to post-procedural culprit vessel TIMI (0-1: 90, 3.26%; 2: 61, 2.20%; 3: 2,616, 94.54%). Results: The following mortality values were obtained in TIMI 0-1, 2, and 3 groups, respectively: in-hospital, 12.22%, 13.11%, 1.72% (p < 0.0001); 1-month, 13.33%, 13.11%, 3.44% (p < 0.0001); 12-month, 15.56%, 16.39%, 6.50% (p < 0.0001); 36-month, 25.56%, 21.31%, 13.91% (p = 0.0007). Mortality rates in patients with final TIMI 0-1 and 2 were not significantly different. Optimal TIMI 3 was independently associated with baseline TIMI 2-3 (OR +/- 95% CI: 7.070 [4.35-11.82]), p < 0.0001; higher ejection fraction (1.30 [1.03-1.63]), p = 0.0038; and family history of coronary artery disease (2.83 [1.17-8.11]), p = 0.0294. Type C lesion, previous heart failure, and PCI without stenting independently predicted suboptimal TIMI 0-2. Conclusions: Only achieving final TIMI 3 in IRA improves outcomes in NSTEMI patients treated with percutaneous coronary revascularization. The mortality rate of near-normal TIMI 2 is comparable to that of TIMI 0-1 after PCI.