Type of thrombus, no reflow and outcomes of coronary intervention in ACS patients: OCT-guided study

Thrombus is the main finding in most patients with acute coronary syndrome (ACS), the type of which potentially impacts the end result of the interventional procedure in terms of no reflow and edge dissection. Optical coherence tomography (OCT) is considered a precise intra-vascular tool to image thrombi and characterise its properties. We aimed to study the impact of thrombus type, as defined by OCT, on procedural outcome in ACS patients. In this retrospective study we enrolled 100 patients who were treated by percutaneous coronary intervention (PCI) with the guidance of OCT. We recorded demographic and clinical data of the whole studied cohort. Angiographic details and procedural data were noted. Baseline OCT study was performed before intervention and repeated post- intervention. Plaque characterisation was identified, and thrombi were defined as red or white thrombi. Acute angiographic outcome was defined with special emphasis on no reflow. Male patients and ST-elevation myocardial infarction (STEMI) patients more often had white thrombi (58.1% and 71.2%, respectively). Cases with red thrombi had longer pain duration, which was statistically significant. Edge dissection was more frequent with red thrombus, 44.7% versus 32.1% with white thrombus, but the difference is not statistically significant, while 17% of patients with white thrombi were complicated by no-reflow phenomenon versus only 4.3% in patients with red thrombi, and this difference was statistically significant. In conculsion, OCT-guided PCI is feasible and safe in ACS settings. OCT- guided intra-procedural differentiation of thrombus type is potentially beneficial in predicting acute procedural outcome.