Metal Stent Implantation Research Articles

Preclinical investigation of neoatherosclerosis in magnesium-based bioresorbable scaffolds versus thick-strut drug-eluting stents

Neoatherosclerosis is a frequent finding after implantation of permanent metallic stents. Bioresorbable scaffolds (BRS) are considered to reduce the incidence of neoatherosclerosis owing to their dissolution and consequent vascular restoration. The aim of this study was to evaluate the formation of neoatherosclerosis between magnesium-based BRS and thick-strut metallic drug-eluting stents (DES) in a rabbit model of neoatherosclerosis and in proportion to the effect of high-dose statin medication. Fully bioresorbable magnesium scaffolds (BRS, n=45) and thick-strut permanent metallic DES of equivalent geometry and design (n=45) were implanted into the iliac arteries of New Zealand White rabbits (n=45) following endothelial balloon injury and exposure to a cholesterol diet. Endothelialisation was assessed in 12 animals after 35 days using scanning electron microscopy (SEM), showing significantly enhanced re-endothelialisation above struts in the BRS (n=13) compared to DES (n=10). Eleven (11) animals were terminated for baseline assessment after 91 days while the remaining 22 animals were randomised to receive high-dose statin treatment (3 mg/kg) or placebo. BRS-treated vessels showed a significant reduction in foam cell infiltration as a sign of early neoatherosclerosis by histology and OCT when compared to thick-strut DES-treated vessels. Statin treatment resulted in significant reduction of foam cell infiltration in BRS and DES by histology. Our findings suggest reduced neoatherosclerosis formation in magnesium-based BRS relative to thick-strut DES. High-dose statin treatment may be a promising measure to reduce neoatherosclerosis progression, both on its own and in synergy with site-targeted device-based treatment.

Randomized comparison between bare-metal stent plus colchicine versus drug-eluting stent alone in prevention of clinical adverse events after percutaneous coronary intervention.

The use of colchicine is associated with a significant reduction of cardiac adverse events in patients with coronary artery disease. Past small randomized trials with oral immunosuppressive or anti-inflammatory therapieshave demonstrated a reduction of adverse clinical events after bare metal stent implantation. The potential role of adjunctive colchicine after bare-metal stentimplantation, compared with drug-eluting stent alone, is unknown. The primary end point of the study will be to compare cost-effectiveness at 1year of follow-up of coronary intervention with bare-metal stentimplantation plus 1 mg of colchicine during 3 months versus percutaneous coronary intervention with drug-eluting stent implantation alone. ClinicalTrials.govidentifier: NCT04382443.

The Predictive Value of Monocyte Count to High-Density Lipoprotein Cholesterol Ratio in Restenosis After Drug-Eluting Stent Implantation.

BackgroundThe clinical value of monocyte count to high-density lipoprotein cholesterol ratio (MHR) in in-stent restenosis (ISR) of patients who have undergone bare metal stent implantation has been studied. However, the predictive value of MHR in ISR for patients who have undergone drug-eluting stent (DES) implantation has not been explored.MethodsNon-ST segment elevation acute coronary syndrome (NSTE-ACS) patients who had undergone DES implantation and coronary angiography follow-up at the Beijing Shijitan Hospital, Capital Medical University, between January 1, 2008, and December 31, 2018, were retrospectively enrolled. Patients were divided into ISR and non-ISR groups depending on the follow-up coronary angiography results. Relative clinical information was recorded and analyzed. The receiver operating characteristic curve analysis was used to determine the optimum cut-off pre-procedural MHR to predict ISR.ResultsA total of 214 patients were enrolled in our study. The mean period between two coronary angiography procedures was 25.4±9.8 months. Percutaneous coronary intervention due to NSTE myocardial infarction, a bifurcation lesion, increased platelet count, and a high MHR were the independent risk factors in multivariate logistic regression analyses.ConclusionOur results indicated that elevated MHR is an independent and useful predictor of ISR in NSTE-ACS patients who have undergone DES implantation.

Coronary circulatory indices in non-infarct related vascular territories in a porcine acute myocardial infarction model

Abstract Background There has been debate on the reliability of fractional flow reserve (FFR) or resting pressure-derived indices in non-IRA of patients with acute ST-segment elevation myocardial infarction. Purpose This study aimed to evaluate temporal changes of coronary hemodynamic and physiologic indices in non-infarct related artery (non-IRA), which might be affected by adjacent infarcted myocardium, using an experimental animal model of acute myocardial infarction (AMI). Methods In Yorkshire swine, acute myocardial infarction was simulated with selective balloon occlusion at left circumflex artery (LCX) as IRA for 30 minutes. Non-IRA stenosis was created using bare metal stent implantation in left anterior descending artery (LAD) 4 weeks before the experiments. Serial changes of systemic hemodynamics, coronary pressure, and Doppler-derived coronary flow velocity were measured in a non-occluded LAD as non-IRA from baseline, balloon occlusion of LCX, and 15 minutes after reperfusion of LCX. Results Among the 6 experimental subjects, the median diameter stenosis of non-IRA was 33.9% (Q1-Q3: 21.7%-46.1%). During balloon occlusion of IRA, there were transient significant changes in both resting and hyperemic aortic pressure (Pa), distal coronary pressure (Pd), averaged peak velocity (APV), trans-stenotic pressure gradient (PG), and microvascular resistance of non-IRA (all P values<0.020). After reperfusion of IRA, the resting APV (P=0.002) and resting trans-stenotic PG (P=0.004) were significantly increased and resting microvascular resistance (P=0.004) was significantly decreased than those in baseline phase. However, the hyperemic APV (P=0.479), hyperemic trans-stenotic PG (P=0.778), and hyperemic microvascular resistance (P=0.816) were not significantly different compared with those in the baseline phase. After reperfusion, the FFR in non-IRA was not significantly different (0.94±0.01 vs. 0.93±0.01, P=0.353), while the CFR (1.93±0.07 vs. 1.36±0.07, P=0.025) and resting Pd/Pa (0.98±0.01 vs. 0.94±0.01, P=0.017) were significantly lower than baseline values. Conclusions In a porcine AMI model, occlusion of IRA induced significant changes of systemic hemodynamics and coronary circulatory indices of non-IRA. However, after reperfusion of IRA, FFR did not change significantly, while resting Summarizing Figure Funding Acknowledgement Type of funding source: Other. Main funding source(s): 1. Philips/Volcano, 2. Bio & Medical Technology Development Program of the National Research Foundation of the Korean government

Distal bare metal stent implantation during thoracic endovascular aortic repair is beneficial to treat complicated type B aortic dissection: A systematic review and meta-analysis.

To explore whether thoracic endovascular aortic repair (TEVAR) plus distal bare metal stent (BMS) implantation leads to favorable clinical outcomes compared with standard TEVAR in treating acute complicated type B aortic dissection. Relevant publications were found through a precise search of PubMed, Cochrane Library, and EMBASE. Count data were calculated as the odd ratio (OR)and 95% confidence interval (CI) using the Mantel-Haenszel statistical method, quantitative data were calculated as mean difference and 95% CI using Inverse Variance statistical method. When the data heterogeneity was large, with an I2 > 50%, a random-effects model and sensitivity analysis were performed. The analysis tool we used was the software Revman 5.3 and G*power 3.1. There were 7 publications involving 958 patients who were enrolled ultimately. The incidence of unplanned secondary intervention and postoperative adverse events in the TEVAR + BMS were lower than standard TEVAR (OR, 0.42, (95% CI, 0.23 to 0.75); OR, 0.57, (95% CI, 0.37 to 0.90)), and the pooled number needed to treat was 15 for unplanned secondary intervention and 15 for postoperative adverse events. There were no significant difference in the aortic-related or all-cause 30-day mortality (OR, 0.81, (95% CI, 0.25 to 2.61); OR, 0.47, (95% CI, 0.18 to 1.22)), aortic-related, all-cause mortality at least 6 months or incidence of the postoperative endoleak (OR, 0.47, (95% CI, 0.17 to 1.32); OR, 0.42, (95% CI, 0.17 to 1.06); OR, 0.81, (95% CI, 0.32 to 2.05)). There is no significant outcome difference except for reduced reintervention but this does not seem to adversely affect survival. It is unclear whether this justifies the additional cost of placing it in every complicated type B aortic dissection regardless of anatomy after standard TEVAR alone. Besides, more data are needed to verify the adjunctive distal bare metal stents' performance at different dissection stages.

Follow-Up Investigation of 41 Children After Metallic Airway Stent Implantation: An 8-Year Experience.

Objective: To present 8-year follow-up outcomes, treatment of complications, and prognosis in children with congenital tracheal stenosis after metallic airway stent implantation.Methods: Retrospective analysis was performed on the clinical records of children who had airway stents placed between May 20, 2011 and May 31, 2016, and on their follow-up records collected on November 31, 2019.Results: During the 8 years follow-up, 41 children underwent airway stenting under flexible bronchoscopy and participated in the follow-up investigation. There were 26 cases with left main bronchus (LMB) stenosis (63.4%), 16 cases with congenital tracheal stenosis (CTS, 39.0%), 12 cases with right main bronchus (RMB) stenosis (29.3%), and 1 case of subglottic stenosis (2.4%). A total of 76 stents were implanted, and 21 patients died after implantation. There were 34 children (82.9%) with congenital heart disease (CHD), while other diseases accounted for <5%. Among children with CHD and those with other conditions, the number of death cases was 19 and 2, respectively; no significant differences were observed between the two groups (P>0.05). The most frequent complications were increased airway secretion (75.8%), stent deformation (66.7%), and granulation tissue hyperplasia (60.6%). The airway stenosis (45.5%) and stent migration (12.1%) occurred at a moderate rate. The less common complications were airway softening (6.1%), and stent breakage (6.1%).Conclusions: The placement and removal of the metallic stent are convenient and quick procedures that can relieve the symptoms of dyspnea caused by airway stenosis in the case of an emergency. After stent implantation, the primary disease should be actively treated, and the stent should be removed as soon as possible after the cause of airway stenosis is successfully removed. Larger stents are more likely to cause complications; thus, a good follow-up system should be established to timely address all the complications.

Combining the Passeo-18 Lux Drug-Coated Balloon and the Pulsar-18 Bare Metal Stent: 12- and 24-Month Outcomes of the BIOLUX 4EVER Investigator-Initiated Trial

Purpose: To report the outcomes after treating stenotic or occluded femoropopliteal lesions with a drug-coated balloon (DCB) followed by the implantation of a thin-strut self-expanding bare metal stent in the BIOLUX 4EVER trial (ClinicalTrials.gov identifier NCT02211664). Materials and Methods: The prospective, multicenter, physician-initiated BIOLUX 4-EVER trial was conducted at 5 centers in Belgium and enrolled 120 patients (mean age 70.9±10.5 years; 79 men) with symptomatic stenotic or occluded de novo femoropopliteal lesions. A fifth of the patients had diabetes mellitus and nearly half had previous peripheral artery interventions. The lesions were a mean 83.3±49.5 mm long with a mean reference vessel diameter of 5.26±0.59 mm. Lesions were treated with a Passeo-18 Lux DCB followed by the implantation of a Pulsar-18 bare metal stent. Follow-up visits were conducted at 1, 6, 12, and 24 months postprocedure; the main outcome was primary patency at 12 months. Results: Technical success was obtained in all patients. Primary patency was observed in 89.9% of patients (95% CI 84.0% to 95.8%) at 12 months and in 83.5% at 24 months (95% CI 89.9% to 97.3%), and freedom from target lesion revascularization was 93.6% (95% CI 89.9% to 97.3%) and 86.1% (95% CI 79.9% to 92.3%), respectively. Ten patients died throughout the course of the trial (90.7% survival at 24 months), all of noncardiovascular causes. The ankle-brachial index improved from 0.68±0.09 at baseline to 0.93±0.11 and 0.93±0.12 at 12- and 24-month follow-up visits (p<0.001). An improvement of at least 1 Rutherford category was observed in 91 of 94 patients (96.8%) at 12 months and 78 of 83 patients (93.4%) at 24 months (p<0.001). Conclusion: The combination of a Passeo-18 Lux DCB followed by a Pulsar-18 stent implantation produced safe and effective outcomes in the treatment of femoropopliteal lesions at up to 24 months. Adding paclitaxel to the bare nitinol stent platform by predilating with a Passeo-18 Lux DCB seems to increase efficacy at 1 and 2 years compared with the use of bare metal stents only, which were investigated in the precursor 4-EVER study.

Self-expandable metal stent of esophagogastric junction versus pyloric area obstruction in advanced gastric cancer patients

Upper gastrointestinal stenting is a palliative treatment for relieving symptoms such as nausea, vomiting, and dietary intake in patients with obstruction due to inoperable advanced stomach cancer. Self-expandable metal stent (SEMS) implantation for malignant obstruction has recently become more effective, safer, and less expensive than operative modality. It also has better short-term outcomes, particularly a shorter hospital stay and a more rapid return to oral intake, than surgical treatment. However, there is no comparative analysis regarding the efficacy, side effects, and survival rate of stenting between the esophagogastric junction (EGJ) and pyloric obstructions.To compare the prognoses and complications after SEMS implantation between EGJ and pyloric obstructions in advanced gastric cancer.Among advanced gastric cancer patients with gastrointestinal obstruction diagnosed from January 2008 to December 2017 at the Gastroenterology Department of Chungnam National University Hospital, 42 and 76 patients presented with EGJ (EGJ obstruction group) and gastric pyloric obstructions (pyloric obstruction group), respectively. We retrospectively reviewed the survival period, changes in food intake, and complications of these patients before and after SEMS placement.The prevalences of aspiration pneumonia were 11.9% (5/42) and 2.6% (2/76) in the EGJ and pyloric obstruction groups, respectively, before SEMS placement (P value: .041). Other symptoms associated with gastric malignant obstruction were not statistically different between the groups. Success rate and adverse events did not significantly differ between the EGJ and pyloric obstruction groups. There was no difference in frequency of stent reinsertion procedures performed owing to reobstruction, but the reprocedure average period was statistically significantly longer in the EGJ obstruction group [EGJ obstruction: 158.3 days (±42.4); pyloric obstruction: 86.0 days (±29.1)] (P value: .022). As an index of improved dietary status, the Gastric Outlet Obstruction Scoring System score was not significantly different between the groups before and after SEMS placement.The EGJ and pyloric obstruction groups did not significantly differ in prognosis or complication rates. However, EGJ stent was more stable than pyloric stent when reobstruction was considered.

Vitamin D attenuates HMGB1-mediated neointimal hyperplasia after percutaneous coronary intervention in swine.

Intracoronary stenting is a common procedure in patients with coronary artery disease (CAD). Stent deployment stretches and denudes the endothelial layer, promoting a local inflammatory response, resulting in neointimal hyperplasia. Vitamin D deficiency associates with CAD. In this study, we examined the association of vitamin D status with high mobility group box 1 (HMGB1)-mediated pathways (HMGB1, receptor for advanced glycation end products [RAGE], and Toll-like receptor-2 and -4 [TLR2 and TLR4]) in neointimal hyperplasia in atherosclerotic swine following bare metal stenting. Yucatan microswine fed with a high-cholesterol diet were stratified to receive vitamin D-deficient (VD-DEF), vitamin D-sufficient (VD-SUF), and vitamin D-supplemented (VD-SUP) diet. After 6months, PTCA (percutaneous transluminal balloon angioplasty) followed by bare metal stent implantation was performed in the left anterior descending (LAD) artery of each swine. Four months following coronary intervention, angiogram and optical coherence tomography (OCT) were performed and swine euthanized. Histology and immunohistochemistry were performed in excised LAD to evaluate the expression of HMGB1, RAGE, TLR2, and TLR4. OCT analysis revealed the greatest in-stent restenosis area in the LAD of VD-DEF compared to VD-SUF or VD-SUP swine. The protein expression of HMGB1, RAGE, TLR2, and TLR4 was significantly higher in the LAD of VD-DEF compared to VD-SUF or VD-SUP swine. Vitamin D deficiency was associated with both increased in-stent restenosis and increased HMGB1-mediated inflammation noted in coronary arteries following intravascular stenting. Inversely, vitamin D supplementation was associated with both a decrease in this inflammatory profile and in neointimal hyperplasia, warranting further investigation for vitamin D as a potential adjunct therapy following coronary intervention.

A potential strategy for in-stent restenosis: Inhibition of migration and proliferation of vascular smooth muscle cells by Cu ion.

The in-stent restenosis (ISR) often happens after the implantation of metal stents, including both bare metal stents (BMSs) and drug-eluting stents (DESs). Drug release from DESs could reduce significantly the occurrence of ISR but also suppress the revascularization and cause thrombosis. In this study, the effect of Cu ion in a range of 0 to 500μM on the migration and proliferation of rat aortic smooth muscle cells (RASMCs) was investigated by a series of in vitro experiments including wound-healing assay, cell viability assay and flow cytometric analysis. It has been found that the critical concentration of Cu ion should be at least 250μM in order to significantly inhibit the migration of RASMCs and the proliferation of RASMCs were impeded by every dose of Cu ion used in this study. In addition, the protein level of caspase-3 was upregulated by 250μM and 500μM Cu2+ exposure, which might be the main reason for RASMCs apoptosis. Thus, it is proposed that ISR might be prevented by the constant release of Cu ion.

Italian Multicenter Registry of Bare Metal Stent Use in Modern Percutaneous Coronary Intervention Era (AMARCORD): A multicenter observational study.

We aimed to evaluate the use of bare metal stent (BMS) implantation in current percutaneous coronary intervention (PCI) era, focusing on indications for use and clinical outcomes. Limited data on BMS usage in current clinical practice are available. All patients who underwent PCI with at least one BMS implantation in 18 Italian centers from January 1, 2013 to December 31, 2017, were included in our registry. Rates of BMS use and reasons for BMS implantations were reported for the overall study period and for each year. Primary outcomes were mortality, bleeding (Bleeding Academic Research Consortium-BARC and Thrombolysis in Myocardial Infarction-TIMI non-CABG definitions), and major adverse cardiac events (MACE) defined as the composite of all-cause and cardiac death, any myocardial infarction, target vessel revascularization, or any stent thrombosis. Among 58,879 patients undergoing PCI in the study period, 2,117 (3.6%) patients (mean age 73 years, 69.7% males, 73.3% acute coronary syndrome) were treated with BMS implantation (2,353 treated lesions). The rate of BMS implantation progressively decreased from 10.1% (2013) to 0.3% (2017). Main reasons for BMS implantation were: ST-elevation myocardial infarction (STEMI) (23.1%), advanced age (24.4%), and physician's perception of high-bleeding risk (34.0%). At a mean follow-up of 2.2 ± 1.5 years, all-cause and cardiac mortality were 25.6 and 12.7%, respectively; MACE rate was 35.3%, any bleeding rate was 13.0% (BARC 3-5 bleeding 6.3%, TIMI non-CABG major bleeding 6.1%). In a large, contemporary, real-world, multicenter registry, BMS use progressively reduced over the last 5 years. Main reasons for BMS implantation were STEMI, advanced age, and physician's perception of high-bleeding risk. High rates of mortality and MACE were observed in this real-world high-risk population.

Impact of coronary calcification on outcomes after ABSORB scaffold implantation: insights from the GABI-R registry

To investigate the outcomes after bioresorbable scaffold (BRS) implantation in calcified coronary lesions. In calcified coronary lesions, durable metallic drug-eluting stent (DES) implantation is associated with worse clinical outcomes compared to noncalcified lesions. Although not recommended, BRSs were frequently implanted in calcified lesions in clinical practice. Their outcome is not well investigated. Between November 2013 and January 2016, 3326 patients were enrolled in the German-Austrian ABSORB ReglstRy (GABI-R). Lesion calcification severity was classified into no (n = 1144), mild (n = 1306), and moderate-to-severe (n = 690) calcification. Patients with calcification were older (none: 59.1 ± 11.2 vs. mild: 61.6 ± 10.9 vs. moderate to severe: 62.4 ± 10.5 years, P < 0.001), had more diabetes (19.1 vs. 20.8 vs. 23.9%, P = 0.015), and more often had previous myocardial infarction (MI) (19.3 vs. 23.1 vs. 25.4%, P = 0.002). Despite a higher rate of postdilatations (P < 0.001), lesions with calcification had more residual stenosis (2.05 ± 9.36% vs. 3.11 ± 9.36% vs. 3.89 ± 9.39%, P < 0.001). Consequently, procedural success was achieved in 97.7 vs. 96.2 vs. 93.6% of cases in none, mild, and moderate-to-severe calcification (P < 0.001). At 24 months, cardiac death (0.3 vs. 0.7 vs. 1.6%, P = 0.009) was higher with increasing calcification. However, no significant between-group difference was observed in the incidence of target vessel MI, target vessel revascularization, or target lesion failure. The rate of probable scaffold thrombosis was significantly higher with increasing calcification. In GABI-R, ABSORB scaffolds in calcified lesions required more postdilation, led to more residual stenosis, but did not portend increased target lesion revascularization over 2 years. Nevertheless, coronary calcification severity emerged as a cardiovascular risk marker and was predictive of cardiovascular mortality. Clinicaltrial.gov NCT02066623.

Real-world analysis of a Biolimus A9 polymer-free drug-coated stent with very short dual antiplatelet therapy in patients at high bleeding risk.

Patients at high risk of bleeding requiring percutaneous coronary intervention (PCI) need careful evaluation of both their thrombotic and their bleeding risks. In these patients, apolymer-free metallic stent coated with biolimus-A9 (BA9-DCS) followed by 1‑month dual antiplatelet therapy (DAPT) could be asafe option; however, real-world data are still lacking. We analyzed the performance of the device in areal-world scenario. Patients assessed as being at high risk of bleeding with an indication for PCI were treated with BA9-DCS and DAPT consisting of aspirin (100 mg/day) and clopidogrel (75 mg/day) for at least 1month, followed by either oral anticoagulation or single antiplatelet therapy. No exclusion criteria were used. The primary endpoint was the occurrence of an adverse event after PCI, i.e. severe bleeding requiring hospitalization, ischemic or hemorrhagic stroke, clinically driven stent thrombosis, myocardial infarction or cardiac death. Overall, 89patients were enrolled in this study [median age 75(66-81)years; 27females (30%)] and 171 interventions were performed. During amedian follow-up of 203 (145-273) days the primary endpoint occurred in 20patients (23%): 12(13%) had clinically significant bleeding, four (5%) ischemic stroke and four (5%) died from cardiac causes related neither to stent thrombosis nor to acute myocardial infarction. Female gender emerged as the only statistically significant predictor of an adverse event (adjusted hazard ratio (HR)3.3; 95% confidence interval (CI): 1.2-8.7, p = 0.017). In real-world patients at high risk of bleeding, implantation of the polymer-free metallic stent coated with Biolimus-A9 (Biofreedom®; Biosensors Europe, Morges, Switzerland) followed by 1-month DAPT showed encouraging results without any stent thrombosis.

A modified predilation, sizing, and postdilation scoring system for patients undergoing metallic drug-eluting stent implantations.

This study sought to assess whether the predilation, scaffold/stent sizing, and postdilation (PSP) score for bioresorbable scaffold (BRS) implantation was associated with outcomes following metallic drug-eluting stent (DES) implantation. The PSP score is associated with patients' prognoses after BRS implantation. This study involved 2,348 patients who underwent biodegradable polymer DES implantations during the PANDA III trial. The optimal PSP technique was defined according to previous studies of BRS implantations. The main outcome was target lesion failure (TLF) that comprised cardiac death, target-vessel myocardial infarction, or ischemia-driven target lesion revascularization. Twenty-five (1.1%) patients fulfilled all the PSP criteria. The BRS-derived PSP score was of limited prognostic value for 2-year TLF after metallic DES implantation; optimal sizing was a protective factor, but optimal predilation was a risk factor. We built a new PSP model for DESs by identifying the following risk factors: predilation performed with a residual stenosis ≥70% or a balloon-to-quantitative coronary angiography (QCA)-determined reference vessel diameter (RVD) ratio >1:1, sizing performed with an RVD <2.25 mm or a stent diameter >0.25 mm wider than the QCA-RVD, a postprocedural stenosis diameter ≥30%, age, and the baseline SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery (SYNTAX) score. The new PSP scoring system predicted 2-year TLF (area under the curve, 0.69; 95% confidence interval, 0.65-0.73); a cutoff value of 19.2 points identified high-risk patients. The new PSP scoring system, based on redefined PSP criteria, age, and the SYNTAX score, could help optimize metallic DES implantations.

Should the Oddis sphincter be retained? A clinical analysis of biliary metal stent implantation in patients with malignant obstructive jaundice.

We sought to analyze the efficacy and safety of preserving the Oddis sphincter during metallic biliary stent implantation in patients with malignant obstructive jaundice. In a retrospective analysis, 133 patients with malignant obstructive jaundice who were admitted to our hospital from January 2010 to January 2017 and who underwent metallic biliary stent implantation were divided into two groups - the Oddis sphincter retention group (n = 55) and the Oddis sphincter nonretention group (n = 78) - according to whether the Oddis sphincter was left untouched during stent placement. The patient clinical data as well as information on complications, time of stent patency, improvement in liver function, and decline of serum bilirubin were reviewed and evaluated. Statistical analysis was performed using the Statistical Package for the Social Sciences version 19.0 (IBM Corp., Armonk, NY, USA, USA) and Prism version 7 (GraphPad Software, San Diego, CA, USA). The median follow-up time was 9.6 months (range: 1-20 months) and there was no significant difference in general clinical information between the two groups. However, the incidence rates of acute biliary infection, recurrent biliary infection, acute pancreatitis, chronic pancreatitis, and asymptomatic pancreatic enzyme levels were higher in the Oddis sphincter retention group and the differences were all statistically significant (P < 0.05). Conversely, there were no significant differences in bilirubin decline, liver function improvement, and stent patency between the two groups (P > 0.05). Leaving the Oddis sphincter untouched during biliary stent placement can reduce the incidence of postoperative complications, while there was no effect on stent patency or jaundice relief. Therefore, it is recommended to preserve the Oddis sphincter when the stenosis is more than 3 cm above the duodenal papilla.

Percutaneous transhepatic cholangiography and drainage and endoscopic retrograde cholangiopancreatograph for hilar cholangiocarcinoma: which one is preferred?

both percutaneous transhepatic cholangiography and drainage (PTCD) and endoscopic retrograde cholangiopancreatography (ERCP) with SEMS implantation have been used for unresectable hilar cholangiocarcinoma (HC) in the clinic for many years. However, which one is preferred is still unknown. to study the effects of biliary drainage of self-expanding metal stents (SEMS) implantation under PTCD or ERCP to treat HC. the clinical data of 82 patients with HC from January 2006 to January 2015 were recorded retrospectively. Patients were treated with biliary implantation of self-expanding metal stents (SEMS) under PTCD (PTCD group, 40 patients) or ERCP (ERCP group, 42 patients). Clinical data, including total bilirubin concentrations, complications and survival time were analyzed. the remission of jaundice was similar in both groups (p > 0.05). The median survival time of the ERCP group and PTCD group were 237 d and 252 d respectively, with no significant differences (p > 0.05). The biliary infection rates under ERCP and PTCD procedure were 52.4 % and 20.0 % respectively, with a significant statistical difference (p < 0.05). For those HC patients of Bismuth III/IV, the infection rates under ERCP and PTCD procedure were 58.3 % and 14.3 %, respectively (p < 0.05). both PTCD and ERCP with SEMS implantation were effective to prolong the survival time of HC patients. The biliary infection rates were higher in the ERCP group, especially for Bismuth III/IV HC patients.

Effect of the type of a coronary stent on dynamics of quality of life in patients with ischaemic heart disease

The purpose of the present study was to investigate the dynamics of quality of life in patients with ischaemic heart disease before and after implantation of a coronary stent depending on the stent's type and patient's gender. The authors analysed the dynamics of quality of life in a total of 120 patients with ischaemic heart disease. The patients were subdivided into two equal groups of 60 each. Group One patients were subjected to implantation of bare-metal stents, whereas Group Two patients received stents coated with zotarolimus as an antiproliferative agent. The control group was composed of 60 people who did not suffer from ischaemic heart disease and were comparable by the age and gender. Quality of life was investigated prior to stent implantation and 6, 12 and 24 months thereafter with the use of the SF-36 questionnaire. It was determined that the indices of quality of life before stenting of coronary arteries was higher in men than in women. However, no gender-related differences were revealed after stent implantation. The dynamics of the parameters of quality of life of patients following implantation of uncoated metal stents within 6 months turned out to have a positive and then rapidly progressing negative course, whereas implantation of stents coated with antiproliferative drug zotarolimus was within 12 months followed and accompanied by a positive and then slowly progressing negative course.

The choice of treatment for myocardial infarction based on individual cardiovascular risk and symptoms of coronary heart disease

According to the data of hospital mortality of patients of the Shymkent cardiological center, the most frequent case of the indicator at the stationary stage in patients with myocardial infarction occurs when the class of acute heart failure according to Killip II-IV is determined in patients, the level of blood glucose is more than 8.0 mmol/l, the level of blood creatinine is more than 123.8 mmol/l and the absence of arterial hypertension when entering the clinic. The main causes of mortality among such elderly and senile patients were Killip class II-IV, blood glucose level of more than 7.30 mmol/l, blood creatinine level of more than 141.4 mmol/l, belonging to the female sex and the absence of hypertension on admission. Implementation of coronary artery stenting taking into account risk factors affecting mortality in hospital in patients with acute myocardial infarction leads to a decrease in hospital mortality and long-term mortality, compared with conservative treatment. Implantation of drug-coated stents and uncoated metal stents equally reduced the mortality rate of myocardial infarction in patients. In elderly and senile patients with myocardial infarction in combination with diabetes mellitus after coronary artery stenting there is a deterioration in long-term survival. Long-term survival at the end of 2010-2018 was 83.67%, while in patients with concomitant diabetes mellitus - only 40.03%, p=0.045 (Log-rank test). Thrombolytic therapy did not improve survival in hospital and long-term patients in the elderly and senile age group. Implementation of thrombolysis in elderly and senile patients hospitalized up to 1.5 hours from the onset of symptoms of myocardial infarct, leads to an unreliable reduction in mortality (p=0.085), hospitalized later than 1.5 hours - there is an increase in mortality compared with patients without thrombolysis(p=0.848). Coronary stenting in acute myocardial infarction reduced mortality in elderly and senile patients regardless of the time between the onset of symptoms of myocardial infarction and hospitalization (p=0.486 and p=0.004).

The mechanism of PDA/PEI/5-Fu coated esophageal stent material on inhibiting cancer associated pathological cells.

Metal stent implantation is usually applied to alleviate nonoperative palliative esophageal obstruction for esophageal cancer in the later period. However, in-stent restenosis after stent implantation limits the esophageal stents' performance due to lack of effective suppression of pathological cells from cancer microenvironment. In previous work, we modified the esophageal stent material 317L stainless steel (317LSS) surface with a poly-dopamine/poly-ethylenimine/5-fluorouracil layer (PDA/PEI/5-Fu), which had strong anti-tumor and anti-restenosis functions. Nevertheless, the mechanism of PDA/PEI/5-Fu layer against tumor and inflammation remains unclear. In this work, we revealed the mechanism of PDA/PEI/5-Fu suppressing the esophageal cancer related pathological cells (esophageal tumor cells, epithelial cells, and fibroblast) and inflammatory cells (macrophages) via series of experiments. Our data suggested that the PEI inhibited viability and E-cadherin expression of the pathological cells, and blocked the NF-κB signal pathway (reducing levels of p-NF-κB proteins). The loaded 5-Fu inhibited the inflammatory factors (TNF-α and IL-1β) release and promoted the anti-inflammation/anti-tumor factors (IL-10 and IL-4) release from macrophages, and also suppressed pathological cells migration; both the PEI and 5-Fu contributed to the upregulation of Bax and Caspase-3 (pro-tumor-apoptosis factor), as well as the downregulation of Bcl-2 (anti-tumor-apoptosis factor) in esophageal tumor cells. All the results showed that PDA/PEI/5-Fu coating had potential multipath anti-cancer and anti-inflammatory effects in the surface modification of esophageal stents.

Investigation of the cytotoxic effects of magnesium alloys on cell cultures

Background. Metallic stent implantation is associated with an increased risk of adverse events, such as prolonged endothelial dysfunction, constant traumatisation of the vessel wall, chronic local inflammation and thrombosis. Thus, the development and manufacturing of bioresorbable stents, which maintain the required support during the vessel healing period and completely dissolve without any side effects, is highly relevant. At present, magnesium alloys are regarded the most applicable for this purpose due to their low corrosion resistance and high biocompatibility.Aim. To assess the cytotoxicity of different magnesium alloys in vitro.Methods. Using strain tempering, seven samples with different yield stress levels were produced: sample 1, MgZnZr (ZK60) 310 МPа; sample 2, MgZnCa (ZX10) 60 МPа; sample 3, MgZnCa (ZX40) 130 МPа; sample 4, MgYZn (WZ31) 300 МPа; sample 5, MgYZn (WZ31) 275 МPа; sample 6, MgYZn (WZ20) 340 МPа and sample 7, MgZnZr (ZK60) 180 МPа. The samples were incubated in a culture medium to obtain the extract, which was further tested on immortalised human fibroblasts. The cytotoxicity of the obtained extract was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, optical microscopy and pH test.Results. In MTT assay, sample 7 was significantly cytotoxic (mean cell survival: 48% [2% ± 1%]), whereas sample 5 was slightly cytotoxic (mean cell survival: 81% [4% ± 14%]). In optical microscopy, the same samples showed the lowest cell density. In flow cytometry, the number of necrotic cells significantly increased in sample 7 (8.25%) and only slightly increased in samples 1 and 5 (3.449% and 3.626%, respectively). Furthermore, samples 5 and 7 showed the highest medium pH.Conclusion. The composition and strain tempering method magnesium alloys are directly correlated with the degree of cell necrosis, change in morphology and medium pH in vitro.Received 7 June 2019. Revised 28 October 2019. Accepted 6 November 2019.Funding: The work is supported by the Ministry of Science of Russian Federation (project RFMEFI58317X0070).Conflict of interest: Authors declare no conflict of interest.