Clinical outcomes in patients treated for coronary in-stent restenosis with drug-eluting balloons: Impact of high platelet reactivity

Prognostic Value of High-Sensitivity C-Reactive Protein in In-Stent Restenosis: A Meta-Analysis of Clinical Trials

Background: A risk assessment of in-stent restenosis (ISR) patients is critical for providing adequate treatment. Nevertheless, the prognostic value of high-sensitivity CRP (hs-CRP) levels on ISR has not been consistently demonstrated in clinical studies. In the current meta-analysis, we aim to assess the predictive role of hs-CRP in patients treated with stenting. Methods: We searched PubMed, Web of Science, Embase, and the Cochrane Registry through May 2022. We selected random control trials that compared the effects of different interventions, and that revealed the effects of hs-CRP. Two reviewers independently screened the articles, extracted the data, and assessed the quality of the studies according to the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The data were pooled using a random-effects meta-analysis. Results: Nine articles were included in the meta-analysis. A total of 1.049 patients received stent implantation, and 185 ISR events were recorded during the 1–12-month follow-up period. Baseline hs-CRP levels were not associated with the prediction of ISR among patients receiving stent implantation. The OR of hs-CRP for ISR was 1.81 (0.92–2.69). In the subgroup analysis, 6–12-month hs-CRP levels, diabetes mellitus (DM), and age ≥60(years)were associated with a higher risk of ISR. Conclusions: This meta-analysis shows that higher levels of baseline hs-CRP are not associated with an increased risk of ISR in stented patients. However, an increased risk of ISR was associated with hs-CRP levels at 6 to 12 months of follow-up, which is higher in studies with diabetes mellitus patients and the elderly.

Platelets in In-stent Restenosis: From Fundamental Role to Possible Prognostic Application

BACKGROUND

Introduction of new generations of stents has decreased the percentage of patients experiencing in-stent restenosis (ISR) following the implantation of stent. However, a large number of patients are still afflicted with this phenomenon, which necessitates further study of ISR pathophysiology.

METHODS

Relevant English literature was searched up to 2018 and retrieved form the PubMed database and Google Scholar search engine. The following keywords were used: "In-stent restenosis", "Platelet", "Chemokine", "Inflammation", "Vascular smooth muscle cell" and "Neointima".

RESULTS

Previous studies have shown that ISR is a pathophysiologic response to damage of the artery wall after its elongation and separation of the atherosclerotic plaque. Development of neointimal hyperplasia (NIH) following this pathophysiologic response is a function of inflammation caused by platelets, monocytes, macrophages, and lymphocytes, as well as rapid migration and proliferation of generally quiescent cells in the median layer of the artery wall.

CONCLUSION

After damage to the artery wall, platelets play an essential role in the incidence of NIH by contributing to inflammation and migration of vascular smooth muscle cells and extracellular matrix remodeling, especially via secretion of different chemokines; therefore, developing therapeutic strategies for platelet inhibition in a controlled manner could be the basis of preventive treatments in the near future. In this study, for the first time, we hypothesize that evaluation of platelet activity profile in patients before and after stent implantation may determine the prognosis and likelihood of ISR.

Value of Rotational Thromboelastometry and Impedance Aggregometry for Evaluating Coagulation Disorders in Patients With Cyanotic and Nongenetic Congenital Heart Disease

Adults with cyanotic congenital heart diseases (CCHD) have a higher risk for bleeding, but also for thrombosis. Rotational thromboelastometry (RT), using tissue factor (EXTEM), a contact activator (INTEM) or cytochalasin (FIBTEM), assesses coagulation by determining the time to initiation of clotting (CT) and clot firmness (MCF) including platelet-fibrin-interaction. The aim of this study was to evaluate RT and whole blood impedance aggregometry (IA) in CCHD compared with a control group without chronic cyanosis (NCCHD). These were used to establish normal reference ranges. We prospectively included 124 patients (76 CCHD, 48 NCCHD). Mean oxygen saturation in CCHD was 81.5%, and 98% in NCCHD (p <0.001). Fifty-five CCHD and 1 NCCHD had pulmonary hypertension. Eisenmenger syndrome was present in 39 CCHD (51.3%). Hemoglobin, hematocrit, and reticulocyte levels were significantly higher in CCHD, and they also showed more thrombocytopenia. Platelet aggregation was under normal range in 89.5% of CCHD after triggering with ADP, in 85.5% after triggering with arachidonic acid (ASPI) and in 73.7% after TRAP-6. RT showed significantly longer clotting times and reduced clot firmness in both EXTEM and INTEM tests. FIBTEM-MCF was also significantly reduced. Moderate inverse correlation was found between platelet count and erythrocytes (r = -0.608, p <0.001). Significant correlations were found between platelet number and RT-parameters as well as with all IA parameters. In conclusion, according to RT and IA, CCHD present hypocoagulable disorders. No signs of hypercoagulability were found.