Integrated backscatter-intravascular ultrasound and modification of plaque during excimer laser coronary angioplasty

This study aims to test the hypothesis that the effect of excimer laser coronary angioplasty (ELCA) not only vaporizes thrombi and their underlying coronary plaque, it also changes their quality. We performed a series of cross-sectional analyses in 52 lesions in 51 patients before and after ELCA with integrated backscatter-intravascular ultrasound (IB-IVUS). The constituent parts of the plaque can be assessed by IB-IVUS (i.e., calcified, fibrous, lipid) according to integrated backscatter values. Minimum lumen diameter, lumen volume and vessel volume expanded after ELCA, while plaque volume did not significantly decrease. There was also a decrease of ‘lipid’ component (35.4–30.3%, P < 0.001) and an increase of IB-IVUS-derived ‘fibrous’ part (34.5–38.3%, P < 0.001). These results may help in understanding plaque change after ELCA. Excimer laser coronary angioplasty seems to contribute to the modification of coronary plaque composition in addition to debulking it.

Five-year major adverse cardiac and cerebrovascular events of patients with lipid core abutting lumen (LCAL) on integrated-backscatter intravascular ultrasound undergoing PCI with current DES

Background Percutaneous Coronary Intervention (PCI) using the new generation drug-eluting stent (DES) has been extremely reduced target lesion revascularization (TLR) in recent years. However, a high incidence of non-target lesion-related cardiovascular events in patients undergoing PCI is an important problem to be solved. According to the previous findings, patients with vulnerable plaques particularly have a high recurrence of cardiovascular events. Little studies, however, has been done to examine the relationship between plaque characteristics on intravascular imaging in a target lesion and non-target lesion-related cardiovascular events. Purpose The main objective of this study is to investigate the five-year major adverse cardiac and cerebrovascular events (MACCE) of patients with lipid core abutting lumen (LCAL) on integrated backscatter intravascular ultrasound (IB-IVUS) in a target lesion undergoing PCI with current DES. Methods and results Between February 2010 and September 2013, in total 780 patients with ischemic heart disease undergoing PCI, 166 target lesions in 166 consecutive patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) and stable angina pectoris (SAP) undergoing IVUS-guided PCI were studied. Plaque characteristics in all target lesions were analyzed by three-dimensional IB-IVUS system using the mechanical IVUS catheter. Our previous study has found that LCAL which is defined as a lipid pool directly in contact with the lumen visualizes the thin fibrous cap of less than 75μm on optical coherence tomography (OCT). On the basis of this data, LCAL at minimal lumen area (MLA) site was identified. In total, 39 patients had lesions with LCAL at MLA site (LCAL(+)), and 127 patients had those without LCAL (LCAL(−)). The primary endpoint was defined as MACCE, including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and non-TLR for the new lesion during a median follow up of five years. The MACCE occurred significantly higher in the LCAL(+) than in the LCAL(−) (38.5% vs. 17.3%; p&lt;0.005). And the Kaplan-Meier estimates have shown that the cumulative incidence of MACCE was significantly higher in the LCAL(+) than in the LCAL(−) (log rank test, p=0.041). Additionally, after adjustment for confounders, gender, prior PCI and LCAL was the independent predictors for the MACCE of patients undergoing PCI with current DES. Furthermore, after adding LCAL to a baseline model with established factors consisting of age, gender, diabetes mellitus, prior PCI and percentage lipid volume on IB-IVUS, the net reclassification (p&lt;0.002) and integrated discrimination improvement (p&lt;0.004) significantly improved compared to baseline model alone. Conclusions In this study, it has become clear that LCAL on IB-IVUS is likely to be a surrogate marker of MACCE in patients undergoing PCI with current DES. Funding Acknowledgement Type of funding source: None

P3388Five year outcomes of patients with lipid rich plaque detected three-dimensional Integrated-Backscatter intravascular ultrasound (IB-IVUS) in target lesion after second generation DES implantation

Background Elective percutaneous coronary intervention (PCI) using second generation drug-eluting stent (DES) has been dramatically reduced restenosis rate. Recently, it has been reported that plaque characterization in nontarget lesion is associated with cardio-vascular events in ischemic heart disease patients undergoing elective PCI. However, it is unclear whether plaque characterization in target lesion is predictor of MACEs (major adverse cardiac events) after elective PCI. Purposes The aim of this study is whether plaque characterization detected integrated-backscatter intravascular ultrasound (IB-IVUS) in the target lesion is associated with MACEs in patients with PCI after second generation DES implantation. Methods and results Of 700 patients with ischemic heart disease, 552 patients were excluded for chronic totally occlusion, severe calcification hindering precise intracoronary imaging, tortuous lesions, ostial or left main stem lesions and ST-elevated myocardial infarction patients. Finally, 148 consecutive patients who consented to repeated IB-IVUS prior to undergoing elective PCI were recruited in the study.Plaque characterization in target lesion was identified for three-dimensional IB-IVUS technology using the mechanical IVUS catheter (ViewIT, 40 MHz, 2.5 Fr; Terumo, Tokyo, Japan). The median of percentage lipid volume in all target lesions was 47.6%. Furthermore, lipid rich plaque (LRP) group was defined as the lesions consisting of percentage lipid volume greater than the median. And, non-lipid rich plaque (non-LRP) group was defined as the lesions consisting of percentage lipid volume less than the median. MACEs were defined as cardiovascular death, target vessel myocardial infarction, target lesion revascularization and stent thrombosis. The median of follow up period was 60 months. Of the 148 patients, 106 patients had stable angina pectoris. The remaining 42 patients are acute coronary syndrome (NSTE-ACS). 74 patients were classified LRP groups and 74 patients were non-LRP groups. No significant differences were observed between the two groups with respect to age, sex and coronary risk factors. While plaque and vessel volume were greater in the LRP group (216.9±116.3mm3, p<0.001) than non-LRP group (322.5±144.0mm3, p p<0.001). Remodeling index was greater in LRP group (1.02±0.18) than non-LRP group (0.93±0.18, p<0.003). Although MACEs were no significant differences between the two groups, the number of MACEs tend to be more in patients with LRP group (8.1±27.4%) than small lipid group (2.7±16.3, p<0.147). Especially, cardiac death tend to be more in LRP group (6.7±25.2% than non-LRP group (1.3±11.6, p<0.096). Conclusions In conclusion, lipid rich plaque detected by three dimensional IB-IVUS system in target lesion with patients undergoing elective PCI may be associated with clinical outcomes for five years after second generation DES implantation. Acknowledgement/Funding None