Relationship between non-culprit lesion plaque characteristics changes and in-stent neoatherosclerosis formation: 1-year follow-up optical coherence tomography study.

The relationship between the in-stent neoatherosclerosis (ISNA) formation and the plaque's characteristic changes in the non-culprit lesion is unclear. We aim to investigate the plaque characteristics changes at non-culprit lesions between patients with ISNA and without ISNA formation at 1-year follow-up. We retrospectively enrolled patients who had DES implantation in de novo lesion and underwent immediately after stenting and 1-year follow-up optical coherence tomography (OCT) examination. OCT-defined ISNA was defined as the presence of lipid-laden neointima or calcification within the culprit stent with a longitudinal extension of ≥1 mm. Non-culprit lesions were divided into two groups: ISNA group (with ISNA) and non-ISNA group (without ISNA). Plaque characteristics of non-culprit lesions were evaluated at baseline and 1-year follow-up. In total, 89 patients with 89 non-culprit lesions (ISNA: n = 37; non-ISNA: n = 52) were included in the analyses. The lesions in the ISNA group show a smaller minimum lumen area compared to the non-ISNA group at 1-year follow-up (2.57 ± 1.08 mm2 versus 3.20 ± 1.62 mm2, p = 0.044). The lesions of the ISNA group show a significant decrease in minimum lumen area changes percent (-7.25% versus 6.46%, p = 0.039). And there are more lesions with minimum lumen area (64.9% versus 38.5%, p = 0.014) and minimum lumen diameter (64.9% versus 40.4%, p = 0.023) decrease in the ISNA group. Furthermore, the lesions in ISNA group have more plaques with lipid core length increase (25.0% versus 10.0%, p = 0.040), more plaques with FCT decrease (50.0% versus 74.0%, p = 0.027) and less TCFA change to non-TCFA (33.3% versus 87.5%, p = 0.010). The plaque characteristic changes in non-culprit lesions are closely related to ISNA formation. The ISNA formation may accompany by a tardier plaque stabilization process in non-culprit lesions.

Clinical Influencing Factors of Acute Myocardial Infarction Based on Improved Machine Learning.

At present, there is no method to predict or monitor patients with AMI, and there is no specific treatment method. In order to improve the analysis of clinical influencing factors of acute myocardial infarction, based on the machine learning algorithm, this paper uses the K-means algorithm to carry out multifactor analysis and constructs a hybrid model combined with the ART2 network. Moreover, this paper simulates and analyzes the model training process and builds a system structure model based on the KNN algorithm. After constructing the model system, this paper studies the clinical influencing factors of acute myocardial infarction and combines mathematical statistics and factor analysis to carry out statistical analysis of test results. The research results show that the system model constructed in this paper has a certain effect in the clinical analysis of acute myocardial infarction.

Localization of in-stent neoatherosclerosis in relation to curvatures and bifurcations after stenting.

BACKGROUND: In-stent neoatherosclerosis (ISNA) is a final common pathway of late-stent failure. However, distribution of ISNA has been little reported. This study was to evaluate the localization of ISNA in relation to curvatures and bifurcations after stent implantation using optical coherence tomography (OCT). METHODS: We retrospectively selected patients who underwent OCT examination ≥12 months after stent (sirolimus-eluting stents, SES) implantation. A stent curvature was defined if the angulation of the stent segment was >29°. Distribution of ISNA in relation to stent curvature and bifurcation was evaluated. RESULTS: Totally, 331 patients were enrolled. The mean follow-up time was 15 months. Forty-one (12.3%) patients were found with ISNA. OCT results showed that stents with ISNA had thicker neointima (mean neointima thickness: 0.16 vs. 0.08 mm, P<0.001) compared to patients without ISNA. Segments with angulation >29° had a higher prevalence of ISNA compared with to angulation ≤29° [18 (18.4%) vs. 23 (9.9%), P=0.032]. ISNA was more frequently located at the "inner curvature" than the "outer curvature" (77.8% vs. 22.2%, P=0.018). If ISNA occurred in a branch, it was more often on the opposite side of the branch compared with the same side of the branch [21 (77.8%) vs. 6 (22.2%), P=0.004]. CONCLUSIONS: Localization of ISNA is related to vessel curvatures and bifurcations. ISNA occurs more often on the inner curvature and the opposite side of the branch.

Impact of Age on Stent Strut Coverage and Neointimal Remodeling as Assessed by Optical Coherence Tomography.

While older age associates with adverse percutaneous coronary intervention (PCI) outcomes, detailed information relating age to stent strut coverage and neointimal characteristics is lacking. One hundred nineteen patients with 123 sirolimus-eluting stents (SESs) were divided into 3 groups: group A (≤55 years), group B (56-65 years), and group C (>65 years). At 6 and 12 months of follow-up, optical coherence tomography was performed to assess strut coverage and neointimal remodeling. At 6 months, the proportion of uncovered struts increased with age: 6.1% in group A versus 7.3% in group B versus 11.7% in group C (P < 0.001) while the proportion of embedded struts decreased: 72.1% versus 57.0% vs. 55.0%, respectively (P < 0.001). Mean neointimal thicknesses were 90  µm versus 60  µm versus 60  µm, respectively (P < 0.001), and neointimal areas were 0.82  mm2 versus 0.52  mm2 versus 0.57  mm2 (P < 0.001). At 12 months, the proportion of uncovered struts increased with age (3.9% vs. 3.3% vs. 4.9 %; P < 0.001), while mean neointimal thicknesses were 100 versus 70 versus 80  µm (P < 0.001) and neointimal areas were 0.87 versus 0.60 versus 0.67  mm2 (P < 0.001). Patients ≤55 years receiving SES showed highest strut coverage and neointimal repair rate compared with the other 2 groups. A "catch-up phenomenon" appeared to occur in the oldest patients, as in the first 6 months the neointima showed lowest endothelial cell coverage and lowest neointimal proliferation rate, whereas from 6 to 12 months, the highest neointimal proliferation rate was seen in the oldest patients.

A rabbit model of spontaneous thrombosis induced by lipopolysaccharide.

AIM: Inflammation plays a critical role in the development of atherosclerotic plaque, and lipopolysaccharide (LPS) is a potentially important source of inflammation. The aim of this study was to develop a rabbit model of spontaneous thrombosis mimicking the pathophysiological and morphological characteristics of atherosclerotic plaque in humans. METHODS: The rabbits were randomized into four groups: group A (n=10) received a normal diet; group B (n=10) received a regular diet and weekly LPS injections (1 µg/kg, Escherichia coli); group C (n=15) received a cholesterol-enriched diet before and after sustaining a balloon injury to the right common carotid artery; and group D (n=15) was treated the same as group C in addition to receiving LPS injections. The morphological characteristics of the resulting lesions were evaluated using optical coherence tomography (OCT) and histology. RESULTS: No significant atherosclerotic plaque was observed in groups A or B. Group D exhibited a higher incidence of spontaneous luminal thrombi than group C or B (60% vs. 20% vs. 10%, p<0.05). All of the thrombi detected with OCT were confirmed on histology. A good correlation between the fibrous cap thickness and thrombus arc was obtained on OCT and the histological evaluations. CONCLUSIONS: A rabbit model of LPS-induced spontaneous thrombosis was developed in which OCT was used to follow changes in plaque morphology.