Abstract 13439: Change to Detection of Plaque Rupture By High-Definition Intravascular Ultrasound in Patients With Acute Coronary Syndrome

BackgroundOptical coherence tomography (OCT) has high image resolution that allows in vivo assessment of plaque characteristics in acute coronary syndrome (ACS) lesions. However, few disadvantages (e.g., poor representation for coronary ostium, the need for complete blood removal and poor penetration depth) limits the utility of OCT in some situations. High-definition intravascular ultrasound (HD-IVUS) is the most recently developed IVUS technology with higher resolution of 60 MHz range than conventional IVUS, which is expected to be a high performance diagnostic tool like OCT. However, the diagnostic accuracy for HD-IVUS remains poorly understood. Therefore, we evaluated the diagnostic performance of HD-IVUS for plaque characteristics in ACS lesions.MethodThis study was a prospectively planned single center study. From September 2017 to May 2018, consecutive ACS patients were enrolled. Patients with cardiac arrest and lesions with in-stent restenosis were excluded. Both OCT and HD-IVUS for culprit lesions were performed just after thrombus aspiration. Diagnosis by OCT was used as gold standard and plaque characteristics were classified into plaque rupture, plaque erosion and calcified nodule. Observer blinded to the information of angiography and OCT evaluated the plaque characteristics by HD-IVUS.ResultA total of 52 patients were enrolled in this study. HD-IVUS were performed for 52 patients (100%), and OCT were performed for 39 patients (75.0%). OCT was avoided due to poor TIMI flow (4 patients) and ostium lesion (1 patients). In 8 patients who underwent OCT, image quality was poor due to incomplete blood removal. Finally, 27 patients underwent both OCT and HD-IVUS (9 patients with non-ST elevation ACS and 18 patients with ST elevation ACS). In OCT assessments, there were 12 patients with plaque rupture (44.4%) and 14 patients with plaque erosion (51.9 %) (definite erosion 3, probable erosion 11). Of 12 patients with plaque ruptures, 11 patients were also diagnosed as plaque rupture by HD-IVUS. Sensitivity and specificity of HD-IVUS for plaque rupture was 92% and 100%, respectively.ConclusionHD-IVUS is more widely available than OCT for ACS patients and has high diagnostic performance for identification of plaque rupture.