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%, =0.002) and hypertension (50.6% vs 37.1%, =0.018) and a lower incidence of retrograde filling grade >2 (34.8% vs 47.1%, =0.036). Patients with CSF/NRP had a higher neutrophil ratio (55.6±19.4 vs 52.4±18.3, =0.038) and levels of low-density lipoprotein (LDL; 3.0±0.8 vs 2.8±0.6, =0.029), fasting glucose (FG; 8.3±1.3 vs 6.8±1.1, =0.005), uric acid (332.6±82.9 vs 308.2±62.8, =0.045), and high-sensitivity C-reactive protein (Hs-CRP; 9.8±4.8 vs 7.3±3.9, =0.036). A multivariate logistic regression analysis revealed that diabetes mellitus (odds ratio [OR], 1.962; 95% confidence interval [CI]: 1.198-2.721; =0.042), mean platelet volume (MPV; OR,1.284; 95% CI, 1.108-1.895; =0.046), LDL cholesterol (LDL-C; OR, 1.383; 95% CI, 1.105-2.491; =0.036), FG (OR, 2.095; 95% CI, 1.495-2.899; =0.018), Hs-CRP(OR, 2.218; 95% CI, 1.556-3.519; =0.029), and retrograde filling of grade >2 (OR, 0.822; 95% CI, 0.622-0.907; =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 (<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.