Incidence, Predictors, and Prognosis of Coronary Slow-Flow and No-Reflow Phenomenon in Patients with Chronic Total Occlusion Who Underwent Percutaneous Coronary Intervention

BACKGROUND: The incidence and prognosis of coronary slow-flow (CSF) and no-reflow phenomenon (NRP) in patients with coronary chronic total occlusion (CTO) who underwent percutaneous coronary intervention (PCI) remain unclear. METHODS: This single-center prospective study aimed to investigate the incidence of CSF/NRP during CTO interventional therapy, determine predictors of CSF/NRP, and evaluate its effect on patient outcomes. RESULTS: In this study, 552 patients with CTO who underwent PCI were included. CSF/NRP occurred in 16.1% of them. They had higher incidences of diabetes mellitus (53.9% vs 36.3%, p=0.002) and hypertension (50.6% vs 37.1%, p=0.018) and a lower incidence of retrograde filling grade >2 (34.8% vs 47.1%, p=0.036). Patients with CSF/NRP had a higher neutrophil ratio (55.6±19.4 vs 52.4±18.3, p=0.038) and levels of low-density lipoprotein (LDL; 3.0±0.8 vs 2.8±0.6, p=0.029), fasting glucose (FG; 8.3±1.3 vs 6.8±1.1, p=0.005), uric acid (332.6±82.9 vs 308.2±62.8, p=0.045), and high-sensitivity C-reactive protein (Hs-CRP; 9.8±4.8 vs 7.3±3.9, p=0.036). A multivariate logistic regression analysis revealed that diabetes mellitus (odds ratio [OR], 1.962; 95% confidence interval [CI]: 1.198–2.721; p=0.042), mean platelet volume (MPV; OR,1.284; 95% CI, 1.108–1.895; p=0.046), LDL cholesterol (LDL-C; OR, 1.383; 95% CI, 1.105–2.491; p=0.036), FG (OR, 2.095; 95% CI, 1.495–2.899; p=0.018), Hs-CRP(OR, 2.218; 95% CI, 1.556–3.519; p=0.029), and retrograde filling of grade >2 (OR, 0.822; 95% CI, 0.622–0.907; p=0.037) were independent predictors of CSF/NRP in CTO patients who underwent PCI. Kaplan-Meier analysis revealed that the patients in the CSF/NRP group had a significantly lower cumulative major cardiac and cerebrovascular events (MACCE)-free survival than those in the non-CSF/NRP group (p<0.0001). CONCLUSION: Of the patients with CTO who underwent PCI, 16.1% developed CSF/NRP and had a significantly lower cumulative MACCE-free survival rate. Diabetes mellitus; higher levels of MPV, LDL-C, FG, and Hs-CRP; and a lower incidence of retrograde filling grade >2 were independent predictors of CSF/NRP in CTO patients who underwent PCI. Thus, they can be used for risk stratification.