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.

Improved Outcomes of Combined Main Branch Stenting and Side Branch Drug-Coated Balloon versus Two-Stent Strategy in Patients with Left Main Bifurcation Lesions

Background. Drug-eluting stent (DES) plus drug-coated balloon (DCB) is a safe and effective treatment strategy for coronary artery bifurcation lesions, but there is no report about this strategy being used for left main (LM) bifurcation lesions. We aim to explore the efficacy and safety of DES plus DCB in the treatment of LM bifurcation lesions. Methods. A total of 100 patients diagnosed with LM bifurcation lesions by coronary angiography were retrospectively enrolled at our center from January 2018 to December 2019. They received either a two-stent strategy or a main branch (MB) stenting plus side branch (SB) DCB strategy and were accordingly divided into the 2-DES group and the DES + DCB group. Patients treated with DES + DCB were compared with a cohort of matched patients treated with a 2-DES strategy. Clinical data was collected and quantitative coronary analysis was performed. Results. For immediate postoperative angiography, though the two groups had no differences in the minimal luminal diameter (MLD) and luminal stenosis of MB, the DES + DCB group had significantly lower SB ostial MLD and a higher degree of residual lumen stenosis than the 2-DES group ( P < 0.05 ). At the time of follow-up, the SB ostial MLD of the DES + DCB group was higher than that of the 2-DES group, but lumen stenosis, late lumen loss (LLL), and LLL at the distal end of the left MB were all smaller than those of the 2-DES group ( P s < 0.05 ). Furthermore, the incidence of lumen restenosis and MACE between the two groups had no significance. Conclusion. The combination of DES and DCB is relatively safe and effective for the treatment of LM bifurcation lesions, and this strategy seems to have advantages in reducing LLL at the SB ostium.

Safety and Efficacy of Drug-Coated Balloons Versus Drug-Eluting Stents in Acute Coronary Syndromes: A Prespecified Analysis of BASKET-SMALL 2

Background: Drug-coated balloons (DCBs) are an established treatment strategy for coronary artery disease. Randomized data on the application of DCBs in patients with an acute coronary syndrome (ACS) are limited. We evaluated the impact of clinical presentation (ACS versus chronic coronary syndrome) on clinical outcomes in patients undergoing DCB or drug-eluting stent (DES) treatment in a prespecified analysis of the BASKET-SMALL 2 trial (Basel Kosten Effektivitäts Trial–Drug-Coated Balloons Versus Drug-Eluting Stents in Small Vessel Interventions). Methods: BASKET-SMALL 2 randomized 758 patients with small vessel coronary artery disease to DCB or DES treatment and followed them for 3 years regarding major adverse cardiac events (cardiac death, nonfatal myocardial infarction, and target vessel revascularization). Results: Among 758 patients, 214 patients (28.2%) presented with an ACS (15 patients [7%], ST-segment–elevation myocardial infarction; 109 patients [50.9%], non–ST-segment–elevation myocardial infarction; 90 patients [42.1%], unstable angina pectoris). At 1-year follow-up, there was no significant difference in the incidence of the primary end point by randomized treatment in patients with ACS (hazard ratio, 0.50 [95% CI, 0.19–1.26] for DCB versus DES) or chronic coronary syndrome (hazard ratio, 1.29 [95% CI, 0.67–2.47] for DCB versus DES). There was no significant interaction between clinical presentation and treatment effect ( P for interaction, 0.088). For cardiac death ( P for interaction, 0.049) and nonfatal myocardial infarction ( P for interaction, 0.010), a significant interaction between clinical presentation and treatment was seen at 1 year with lower rates of these secondary end points in patients with ACS treated by DCB. At 3 years, there were similar major adverse cardiac event rates throughout groups without significant interaction between clinical presentation and treatment ( P for interaction, 0.301). All-cause mortality was higher in ACS compared with chronic coronary syndrome; however, there was no difference between DCB and DES irrespective of clinical presentation. Conclusions: In this subgroup analysis of the BASKET-SMALL 2 trial, there was no interaction between indication for percutaneous coronary intervention (acute versus chronic coronary syndrome) and treatment effect of DCB versus DES in patients with small vessel coronary artery disease. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01574534.

Ticagrelor vs. Clopidogrel in Acute Coronary Syndrome Patients With Chronic Kidney Disease After New-Generation Drug-Eluting Stent Implantation

Background: The impact of ticagrelor-based dual antiplatelet therapy (DAPT) on acute coronary syndrome (ACS) in patients with chronic kidney disease (CKD) remains unclear.Methods: Data on a total of 1,067 ACS patients with CKD including end-stage renal disease (ESRD) who underwent new-generation drug-eluting stent implantation were extracted from a multicenter registry. This study aimed to compare outcomes of patients treated with ticagrelor- (n = 449) and those treated with clopidogrel-based (n = 618) DAPT. Outcomes of interest included major adverse cardiac and cerebrovascular events (MACCEs) and bleeding (Bleeding Academic Research Consortium grade 3 or 5) at 12 months. Propensity-score matching (346 pairs) analysis was performed.Results: The patients with ESRD showed the highest MACCE and bleeding rates (P &lt; 0.001). There was no difference in the rate of MACCEs between the treatment groups (7.8% vs. 8.4%; hazard ratio [HR] = 0.95, 95% confidence interval [CI] = 0.56–1.61, P = 0.855); however, a trend toward an increased bleeding rate was observed in the ticagrelor-based DAPT group (6.8% vs. 3.8%, HR = 1.84, 95% CI = 0.93–3.63, P = 0.079). Among patients with CKD stage III/IV but without ESRD (277 pairs), the ticagrelor-based DAPT group showed a reduced MACCE rate (3.6% vs. 8.7%, HR = 0.41, 95% CI = 0.19–0.86, P = 0.018) and a similar bleeding rate (5.1% vs. 3.2%, HR = 1.61, 95% CI = 0.70–3.71, P = 0.267), compared with those of the clopidogrel-based DAPT group.Conclusion: The effects of ticagrelor-based DAPT on ischemic and bleeding outcomes of ACS patients with CKD varied according to CKD stage; in ACS patients with CKD without ESRD, ticagrelor-based DAPT reduced MACCE risk without increasing bleeding risks, relative to those observed with clopidogrel-based DAPT.

A viewpoint on material and design considerations for oesophageal stents with extended lifetime

Oesophageal stents are meshed tubular implants designed to maintain patency of the oesophageal lumen and attenuate the symptoms of oesophageal cancer. Oesophageal cancers account for one in twenty cancer diagnoses and can lead to dysphasia, malnutrition and the diminishment of patient quality of life (QOL). Self-expanding oesophageal stents are the most common approach to attenuate these symptoms. Recent advances in oncological therapy have enabled patient survival beyond the lifetime of current devices. This introduces new complications for palliation, driving the need for innovation in stent design. This review identifies the factors responsible for stent failure. It explores the challenges of enhancing the longevity of stent therapies and outlines solutions to improving clinical outcomes. Discussions focus on the role of stent materials, construction methods, and coatings upon device performance. We found three key stent enhancement strategies currently used; material surface treatments, anti-migratory modifications, and biodegradable skeletons. Furthermore, radioactive and drug eluting stent designs were identified as emerging novel treatments. In conclusion, the review offers an overview of remaining key challenges in oesophageal stent design and potential solutions. It is clear that further research is needed to improve the clinical outcome of stents and patient QOL.