Culprit Lesion Morphology on Optical Coherence Tomography in ST-elevation Myocardial Infarction vs Non ST-elevation Myocardial Infarction-A Systematic Review of 7526 Patients

Background: Patients with STEMI are postulated to have different culprit lesion morphology compared to NSTEMI. The use of OCT in ACS can help delineate lesion morphology. The aim of this systematic review was to analyze the available data on culprit plaque morphology in ACS patients. Methods: The available literature was systematically screened for studies on culprit lesion morphology in ACS pa-tients. Data was extracted from the selected studies and analyzed for baseline characteristics as well as culprit lesion morphology on OCT. Lesion characteristics between STEMI and NSTEMI groups were compared. Results: A total of 32 studies were selected for the final analysis. The average age of the study population was 62.4 years. Majority of patients (66.6%) had STEMI on presentation. NSTEMI patients had a higher prevalence of diabetes compared to STEMI. Both STEMI and NSTEMI patients had similar prevalence of thin-cap fibroatheroma (44.9%). The mean fibrous cap thickness was 84.2 mm in the study. STEMI patients had higher prevalence of lipid plaques, macro-phages and luminal thrombus as compared to NSTEMI patients. Plaque rupture was the predominant culprit lesion morphology in both STEMI and NSTEMI groups, with higher prevalence in STEMI patients. Plaque erosion was also more common in STEMI patients (34.4% vs 13.2%). Conclusion: Plaque rupture is the predominat culprit lesion morphology in both STEMI and NSTEMI patients, despite having differences in baseline characteristics. Use of OCT to determine plaque morphology in ACS patients can help guide management strategy in select cases. [PROSPERO CRD42021249742].