Late mitral restenosis after percutaneous commissurotomy: Predictive value of inflammation and extracellular matrix remodeling biomarkers

Deficiency of neuropeptide Y attenuates neointima formation after vascular injury in mice

BACKGROUND

Restenosis after percutaneous coronary intervention (PCI) limits therapeutic revascularization. Neuropeptide Y (NPY), co-stored and co-released with the sympathetic nervous system, is involved in this process, but its exact role and underlying mechanisms remain to be fully understood. This study aimed to investigate the role of NPY in neointima formation after vascular injury.

METHODS

Using the left carotid arteries of wild-type (WT, NPY-intact) and NPY-deficient (NPY^-/-) mice, ferric chloride-mediated carotid artery injury induced neointima formation. Three weeks after injury, the left injured carotid artery and contralateral uninjured carotid artery were collected for histological analysis and immunohistochemical staining. RT-qPCR was used to detect the mRNA expression of several key inflammatory markers and cell adhesion molecules in vascular samples. Raw264.7 cells were treated with NPY, lipopolysaccharide (LPS), and lipopolysaccharide-free, respectively, and RT-qPCR was used to detect the expression of these inflammatory mediators.

RESULTS

Compared with WT mice, NPY^-/- mice had significantly reduced neointimal formation three weeks after injury. Mechanistically, immunohistochemical analysis showed there were fewer macrophages and more vascular smooth muscle cells in the neointima of NPY^-/- mice. Moreover, the mRNA expression of key inflammatory markers such as interleukin-6 (IL-6), transforming growth factor-β1 (TGF-β1), and intercellular adhesion molecule-1 (ICAM-1) was significantly lower in the injured carotid arteries of NPY^-/- mice, compared to that in the injured carotid arteries of WT mice. In RAW264.7 macrophages, NPY significantly promoted TGF-β1 mRNA expression under unactivated but not LPS-stimulated condition.

CONCLUSIONS

Deletion of NPY attenuated neointima formation after artery injury, at least partly, through reducing the local inflammatory response, suggesting that NPY pathway may provide new insights into the mechanism of restenosis.

Histopathological Characterization of Mitral Valvular Lesions from Patients with Rheumatic Heart Disease

BACKGROUND

The underlying mechanisms by which rheumatic heart disease (RHD) lead to severe valve dysfunction are not completely understood.

OBJECTIVE

The present study evaluated the histopathological changes in mitral valves (MV) seeking an association between the pattern of predominant valvular dysfunction and histopathological findings.

METHODS

In 40 patients who underwent MV replacement due to RHD, and in 20 controls that underwent heart transplant, histological aspects of the excised MV were analyzed. Clinical and echocardiographic data were also collected. Histological analyses were performed using hematoxylin-eosin staining. Inflammation, fibrosis, neoangiogenesis, calcification and adipose metaplasia were determined. A p value<0.05 was considered to be statistically significant.

RESULTS

The mean age of RHD patients was 53±13 years, 36 (90%) were female, whereas the mean age of controls was 50±12 years, similar to the cases, with the majority of males (70%). The rheumatic valve endocardium presented greater thickness than the controls (1.3±0.5 mm versus 0.90±0.4 mm, p=0.003, respectively), and a more intense inflammatory infiltrate in the endocardium (78% versus 36%; p=0.004), with predominance of mononuclear cells. Moderate to marked fibrosis occurred more frequently in rheumatic valves than in control valves (100% vs. 29%; p<0.001). Calcification occurred in 35% of rheumatic valves, especially among stenotic valves, which was associated with the mitral valve area (p=0.003).

CONCLUSIONS

Despite intense degree of fibrosis, the inflammatory process remains active in the rheumatic mitral valve, even at late disease with valve dysfunction. Calcification predominated in stenotic valves and in patients with right ventricular dysfunction.

Correlation of pre-operative circulating inflammatory cytokines with restenosis and rapid angiographic stenotic progression risk in coronary artery disease patients underwent percutaneous coronary intervention with drug-eluting stents

Background

This study aimed to explore the associations of common inflammatory cytokine levels with restenosis and rapid angiographic stenotic progression (RASP) risk in coronary artery disease (CAD) patients underwent percutaneous coronary intervention (PCI) with drug‐eluting stents (DES).

Methods

Two hundred and ten CAD patients underwent PCI with DES were consecutively recruited, then pre‐operative serum levels of TNF‐α, IL‐1β, IL‐4, IL‐6, IL‐8, IL‐10, IL‐17A, IL‐21, and IL‐23 were determined by ELISA. The 12‐month in‐stent restenosis and RASP of non‐intervened lesion were assessed by quantitative coronary angiography analysis.

Results

The pre‐operative TNF‐α, IL‐6, IL‐17A, and IL‐23 expressions were increased while IL‐4 expression was decreased in restenosis patients compared with non‐restenosis patients. Further analysis revealed that IL‐6, IL‐8, hypercholesteremia, diabetes mellitus, and HsCRP could independently predict restenosis risk, and subsequent ROC curve revealed that their combination was able to differentiate restenosis patients from non‐restenosis patients with an AUC of 0.951 (95%CI: 0.925‐0.978). Meanwhile, the pre‐operative TNF‐α, IL‐6, IL‐17A, IL‐21, and IL‐23 expressions were increased whereas IL‐4 level was decreased in RASP patients compared with non‐RASP patients. Further analysis revealed that TNF‐α, IL‐6, IL‐23, hypercholesteremia, SUA, HsCRP, and multivessel artery lesions could independently predict RASP risk, and subsequent ROC curve disclosed that their combination could discriminate RASP patients from non‐RASP patients with an AUC of 0.886 (95%CI: 0.841‐0.931).

Conclusions

This study unveils the potentiality of pre‐operative circulating inflammatory cytokines as markers for predicting restenosis and RASP risk in CAD patients underwent PCI with DES.