Correlates of the “No-Reflow” or “Slow-Flow” Phenomenon in Patients Undergoing Primary Percutaneous Coronary Intervention

Background: despite recent advances in interventional equipment and techniques, the angiographic no-reflow phenomenon occurs in a considerable number of patients undergoing primary percutaneous coronary intervention (pci). we investigated the clinical, angiographic, preprocedural, and procedural characteristics associated with the no-reflow phenomenon among patients undergoing primary pci. methods: between march 2008 and april 2013, 530 patients (78.5% male, mean age=58.11±12.39 y) with st-segmen televation myocardial-infarction who underwent primary pci were categorized in 2 groups according to their postprocedural thrombolysis-in-myocardial infarction (timi) flow grades: those with a maximum score of 2 (the no- reflow or slow-flow group) and the ones with a score of 3 (the reflow group). a multivariable logistic regression model was used to find the multiple correlates of the no-reflow phenomenon after pci. results: there were 166 (31.3%) patients in the no-reflow group and 364 (68.7%) in the reflow group. the no-reflow patients were older and had significantly longer target lesion lengths, higher synergy between percutaneous coronary intervention with taxus and cardiac surgery (syntax) scores, higher infarct-related artery syntax scores, more thrombus burden, and a higher frequency of initial timi flow grades of 2 or lower. our multivariable logistic regression analysis demonstrated that older age, higher numbers of q waves, not using statin, longer target lesion lengths, higher thrombus grades, and higher infarct-related artery syntax scores remained the independent correlates of increased no-reflow rates after primary pci (area under the roc curve=0.784, 95% ci: 0.742–0.826; p<0.001). conclusion: clinical, angiographic, and procedural features of patients undergoing primary pci may be correlated with the occurrence of the no-reflow phenomenon. the thrombus grade and the infarct-related artery syntax score could be among these factors.