Comparison Between the Incidence of Coronary No-Reflow in Patients with Acute ST-Elevation Myocardial Infarction receiving ticagrelor versus clopidogrel loading doses

Abstract

Background Primary PCI is the preferred reperfusion strategy for ST segment elevation myocardial infarction (STEMI); because it offers prompt and complete recanalization of an occluded infarct-related artery. However, inspite of successfully restored (Thrombolysis in Myocardial Infarction [TIMI] grade 3) epicardial blood flow, myocardial reperfusion is not regained in some patients. This phenomenon is referred to as coronary no reflow. Such patients with no reflow have higher incidence of resting segmental wall motion abnormalities (SWMA), myocardial free wall rupture, and death. Objective To compare the effect of 180 mg ticagrelor versus 600 mg clopidogrel loading doses, on the incidence of no-reflow in acute ST segment elevation myocardial infarction (STEMI) patients. Material and Methods This study was carried out on 100 patients, presented with acute STEMI to Ain Shams university hospitals, in the period between November 2018 and February 2019 who underwent primary percutaneous coronary intervention (PCI). All patients were subjected to history, clinical examination, ECG recording before and after primary PCI, blood samples before primary PCI for (creatinine, CKTotal, CKMB in addition to routine laboratory investigations), and echocardiography after primary PCI. Patients were divided into two groups, where 50 patients received a 600 mg loading dose of clopidogrel and the other 50 received a 180 mg loading dose of ticagrelor prior to primary PCI. The primary endpoint was the occurrence of no reflow defined as TIMI flow grades ≤ 2 and or MBG of 0 or 1. The secondary endpoint was the occurrence of major adverse cardiac events during hospital stay. Results The primary endpoint of no reflow occurred in 17 (34%) patients in the clopidogrel group versus 12 (24%) patients in the ticagrelor group. This difference was not statistically significant (P-value 0.271). There was no significant statistical difference in the occurrence of major adverse cardiac events either. Conclusion The incidence of no reflow does not seem to be affected by the type of P2Y12 inhibitor loading received in the setting of STEMI. Further large-scale multi-center studies are required to prove or disprove the current evidence on the superiority of ticagrelor over clopidogrel in STEMI patients.