Futuristic Developments and Applications in Endoluminal Stenting

Endoscopic stenting is a well-established option for the treatment of malignant obstruction, temporary management of benign strictures, and sealing transmural defects, as well as drainage of pancreatic fluid collections and biliary obstruction. In recent years, in addition to expansion in indications for endoscopic stenting, considerable strides have been made in stent technology, and several types of devices with advanced designs and materials are continuously being developed. In this review, we discuss the important developments in stent designs and novel indications for endoluminal and transluminal stenting. Our discussion specifically focuses on (i) biodegradable as well as (ii) irradiating and drug-eluting stents for esophageal, gastroduodenal, biliary, and colonic indications, (iii) endoscopic stenting in inflammatory bowel disease, and (iv) lumen-apposing metal stent.

Real-World Long-Term Clinical Outcomes of Ultrathin Strut Biodegradable Polymer Drug-Eluting Stents in Korean ST-Segment-Elevation Myocardial Infarction (STEMI) Patients with or without Acute Heart Failure Undergoing Primary Percutaneous Coronary Intervention

Biodegradable polymers (BDPs) and ultrathin struts were recently introduced to drug-eluting stents (DES) to further improve outcomes. In this study, we analyzed and compared the effect of the ultrathin strut BDP-DES (UBDP-DES) with the conventional durable polymer-DES (DP-DES) in patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PPCI). A total of 356 STEMI patients (n = 160 in the UBDP-DES group and n = 196 in the DP-DES group) were enrolled. The primary endpoint was target lesion failure (TLF), including cardiac death, target vessel myocardial infarction, and ischemic-driven, target lesion revascularization (ID-TLR). The mean age was 60.3 ± 12.7 years (male 81.7%), and the median follow-up duration was 63.8 months. TLF was numerically more frequent in the UBDP-DES group (8.1% vs. 4.1%; HR 2.14; 95% CI 0.89–5.18; p = 0.091). Propensity score matching (PSM) was performed to balance discrepancies in the baseline characteristics due to patients in the UBDP-DES group initially having more unstable vital signs. However, after PSM (n = 116 in each group), there was no significant difference in TLF (5.3% vs. 5.3%; HR 1.04, 95% CI 0.34-3.22; p = 0.947) or other secondary endpoints including ID-TLR. In the subgroup analysis, subjects with initial acute heart failure (AHF), defined as Killip class ≥ 3, were associated with 13.6% chance of 30-day mortality (9-fold of those without AHF), although chances of repeat revascularization were low (3.0%). Among patients with AHF, the UBDP-DES group was associated with a numerically higher chance of TLF compared with the DP-DES group. There was no difference in TLF between groups in patients without AHF. This study showed that UBDP-DES has long-term clinical outcomes similar to those of conventional DP-DES in real-world Korean STEMI patients receiving PPCI, especially in those without initial AHF.

Assessment of the role of IL6 and IL10 gene polymorphisms as a risk factor for the development of restenosis in patients after implantation of drug-eluting stents

Relevance. Currently, the number of percutaneous coronary interventions continues to increase, which leads to an increase in the absolute number of restenosis cases, which is the main complication of the long-term postoperative period. The search for risk factors responsible for restenosis and artery re-narrowing mechanisms in order to prevent this complication is an important goal in interventional cardiology. Risk factors for the restenosis development include clinical, angiographic and genetic factors. An active search for biomolecular markers associated with the coronary artery restenosis is currently underway. Objective: to study the role of polymorphic variants C-174G of the IL6 gene and C-819T of the IL10 gene as a risk factor for the development of restenosis in patients after stent implantation. Materials and Methods : The study included 113 patients with stable coronary artery disease, who had previously undergone balloon angioplasty and implantation of drug-eluting stents, and 62 patients with intact arteries that were included to the control group. Statistical data processing was carried out using the R-language program and the SPSS Statistics 20 software package. Results: GG genotype for IL6 gene was associated with the development of coronary artery disease. In the subgroup of patients over 65 years of age and instent restenosis, the GG genotype was significantly less frequent. The homozygous CC genotype for IL10 gene was associated with rapid angiographic in-stent restenosis progression.

Downregulation of TRPC4 and TRPC5 Inhibits Smooth Muscle Cell Proliferation without Affecting Endothelial Cell Proliferation

Aims. The main treatment for coronary heart disease is percutaneous coronary intervention (PCI), and drug-eluting stents are designed to inhibit vascular smooth muscle cell (VSMCs) proliferation and migration causing restenosis by releasing pharmacological agents into the vessel wall. Once drug-eluting stents are deployed, these pharmacological agents exert many biological effects in the coronary circulation, not only inhibition of VSMCs but also extension to vascular endothelial cells (VECs). The purpose of this study was to explore target molecules that inhibit VSMCs proliferation without affecting VECs. Methods. mRNA and protein expressions of transient receptor potential channels (TRPCs) in cultured VSMCs and VECs were determined by western blotting and RT-qPCR. VSMCs and VECs proliferation was evaluated using CCK-8 assays and western blotting of proliferating cell nuclear antigen (PCNA). Calcium backfilling assays were performed to detect intracellular calcium ion concentration in cultured VSMCs and VECs. Results. The TRPC6 expression was more abundant in VECs than VSMCs, while TRPC4 and TRPC5 expressions were more abundant in VSMCs than VECs. Knockdown of TRPC4 or TRPC5 alone had no remarkable inhibitory effect on VSMC proliferation. Synergistic knockdown of TRPC4 and TRPC5 inhibited the proliferation of VSMCs, declined the expression of the PCNA, and reduced the intracellular calcium ion concentration but not VECs. Conclusion. These data suggest that concurrent inhibition of TRPC4 and TRPC5 inhibits VSMCs proliferation without affecting VECs, thus providing novel targets for developing pharmacological agents for drug-eluting stents.