Unloading and successful treatment with bioresorbable stents during percutaneous coronary intervention:A case report

BACKGROUND With the development of percutaneous coronary intervention(PCI),the number of interventional procedures without implantation,such as bioresorbable stents(BRS)and drug-coated balloons,has increased annually.Metal drug-eluting stent unloading is one of the most common clinical complications.Comparatively,BRS detachment is more concealed and harmful,but has yet to be reported in clinical research.In this study,we report a case of BRS unloading and successful rescue.This is a case of a 59-year-old male with the following medical history:“Type 2 diabetes mellitus”for 2 years,maintained with metformin extended-release tablets,1 g PO BID;“hypertension”for 20 years,with long-term use of metoprolol sustained-release tablets,47.5 mg PO QD;“hyperlipidemia”for 20 years,without regular medication.He was admitted to the emergency department of our hospital due to intermittent chest pain lasting 18 hours,on February 20,2022 at 15:35.Electrocardiogram results showed sinus rhythm,ST-segment elevation in leads I and avL,and poor R-wave progression in leads V1–3.High-sensitivity troponin I level was 4.59 ng/mL,indicating an acute high lateral wall myocardial infarction.The patient’s family requested treatment with BRS,without implanta-tion.During PCI,the BRS became unloaded but was successfully rescued.The patient was followed up for 2 years;he had no episodes of angina pectoris and was in generally good condition.CONCLUSION We describe a case of a 59-year-old male experienced BRS unloading and successful rescue.By analyzing images,the causes of BRS unloading and the treatment plan are discussed to provide insights for BRS release operations.We discuss preventive measures for BRS unloading.

Outcomes of a non-randomised audit of single pigtail suture stents in urolithiasis management of Asian patients in Singapore

Objective:Double-J(DJ)ureteric stents are commonly placed perioperatively for semirigid or flexible ureteroscopic renal surgery.It is believed that lesser stent material within the bladder mitigates stent-related symptoms.This study aimed to evaluate the J-Fil ureteral stent,a single pigtail suture stent compared with conventional DJ stent in relation to stent symptoms in an Asian population undergoing ureterorenal intervention.Methods:Based on internal audit committee recommendation approval,the records of 50 patients retrieved,available data of 41 patients who were prospectively enrolled into two groups(Group 1[J-Fil stent group],n=21 and Group 2[DJ stent group],n=20)between August 2020 to January 2021,were analysed.Parameters compared were nature of procedure,stone location and size,ease of deployment or removal,and complications.A modified universal stent symptom questionnaire was used to assess morbidity of stent symptoms within 48 h of insertion and at removal.Results:Both groups had similar median age,distribution in male to female ratio,and stone size.The overall median universal stent symptom questionnaire score at insertion was similar for bladder pain,flank or loin pain,and quality of life between Group 1 and 2;however,at removal Group 1 fared significantly better than Group 2,especially for flank or loin pain and pain at voiding.Both groups had similar ease in insertion with no hospital readmissions.Conclusion:Our audit favoured the single pigtail suture stent in Asian ureters in mitigating stent-related issues.It showed a good safety profile with easy deployment and removal.It promises a new standard in stenting.

Can we predict the incidence of high-grade Clavien-Dindo complications in patients with forgotten encrusted stents undergoing endourologic management?

Objective:Ureteral stents are customarily inserted to facilitate urinary drainage,but they come with their own glitches of being forgotten and/or encrusted leading to serious consequences.The present study aimed to report the complications in patients with forgotten and encrusted stents according to the Clavien-Dindo system specific to urological procedures and identify the factors leading to high-grade(Clavien-Dindo Grade 4A or above)complications.Methods:The hospital records of patients with forgotten encrusted double-J stents over a period of 8 years were reviewed.The parameters recorded included patient demographics,indwelling time,need for percutaneous nephrostomy,hemodialysis,urine culture,blood culture,total blood counts,serum creatinine,radiologic findings,management techniques,number of surgical interventions,modified Clavien-Dindo complications,follow-up,and mortality,if any.Results:Forty patients were included in the study.The median age was 52(range 6-85)years.Of the total,25(62.5%)patients had a“significant”stent load;31(77.5%)had renal failure or acute kidney injury on presentation;19(47.5%)patients had sepsis at presentation.Among the patients presented with sepsis,11(57.9%)patients demonstrated a positive urine culture;and 7/11(63.6%)patients exhibited pan-resistant organisms.Twelve out of 40(30.0%)patients in our series developed high-grade Clavien-Dindo complications.On univariate analysis,sepsis at presentation(p=0.007),stent load(p=0.031),diabetes(p=0.023),positive urine culture(p=0.007),and stent indwelling time of more than 1 year(p=0.031)were found to be significant.On multivariate logistic regression analysis,sepsis at presentation(p=0.017)and positive urine culture(p=0.016)were significant predictors for high-grade complications.Conclusion:It is prudent to identify specific risk factors,namely sepsis at presentation and positive urine culture to triage and optimize these patients before surgical management.

Revolutionizing palliative care:Electrocautery-enhanced lumenapposing metal stents in endoscopic-ultrasound-guided biliary drainage for malignant obstructions

Patients with malignant biliary obstruction,following endoscopic retrograde cholangiopancreatography(ERCP)failure could be referred for endoscopicultrasound-guided biliary drainage through electrocautery-enhanced(ECE)lumen-apposing metal stent(LAMS)placement.However,the efficacy and safety of ECE-LAMS in this scenario have remained debatable due to minimal scientific evidence.The current confirmed 91.0%clinical success,96.7%technical success,7.3%reintervention rate,and 17.5%adverse events,following the treatment of malignant biliary obstruction with ECE-LAMS delivery.Finally,ECE-LAMS proved to be a generalizable strategy for managing biliary obstruction for patients who were excluded from ERCP.

Defining failure of endoluminal biliary drainage in the era of endoscopic ultrasound and lumen apposing metal stents

The role of endoscopy in pathologies of the bile duct and gallbladder has seen notable advancements over the past two decades.With advancements in stent technology,such as the development of lumen-apposing metal stents,and adoption of endoscopic ultrasound and electrosurgical principles in therapeutic endoscopy,what was once considered endoscopic failure has transformed into failure of an approach that could be salvaged by a second-or third-line endoscopic strategy.Incorporation of these advancements in routine patient care will require formal training and multidisciplinary acceptance of established techniques and collaboration for advancement of experimental techniques to generate robust evidence that can be utilized to serve patients to the best of our ability.

Long-term outcomes of titanium-nitride-oxide coated stents and drug-eluting stents in acute coronary syndrome:A systematic review and meta-analysis

BACKGROUND In severe cases of coronary artery disease,percutaneous coronary intervention provide promising results.The stent used could be a drug-eluting stent(DES)or a titanium-nitride-oxide coated stent(TiNOS).AIM To compare the 5-year effectiveness and safety of the two stent types.METHODS The following systematic review and meta-analysis was conducted in accordance with the preferred reporting items for systematic reviews and meta-analysis guidelines,and PubMed/MEDLINE,Scopus,and Cochrane Central were searched from inception till August 2023.Primary outcomes were major adverse cardiac events(MACE),cardiac death,myocardial infarction(MI),cardiac death or MI,and ischemia-driven total lesion revascularization(ID-TLR).RESULTS Four randomized controlled trials(RCT),which analyzed a sum total of 3045 patients with acute coronary syndrome(ACS)after a median follow-up time of 5 years were included.Though statistically insignificant,an increase in the ID-TLR was observed in patients receiving TiNOSs vs DESs.In addition,MI,cardiac death and MI,and definite stent thrombosis(DST)were significantly decreased in the TiNOS arm.Baseline analysis revealed no significant results with meta-regression presenting non-ST elevated MI(NSTEMI)as a statistically significant covariate in the outcome of MACE.CONCLUSION TiNOS was found to be superior to DES in terms of MI,cardiac death or MI,and DST outcomes,however,the effect of the two stent types on ID-TLR and MACE was not significant.A greater number of studies are required to establish an accurate comparison of patient outcomes in TiNOS and DES.

Unveiling the potential of electrocautery-enhanced lumen-apposing metal stents in endoscopic ultrasound-guided biliary drainage

This editorial delves into Peng et al's article,published in the World Journal of Gastrointestinal Surgery.Peng et al's meta-analysis investigates the effectiveness of electrocautery-enhanced lumen-apposing metal stents(ECE-LAMS)in ultrasound-guided biliary drainage for alleviating malignant biliary obstruction.Examining 14 studies encompassing 620 participants,the research underscores a robust technical success rate of 96.7%,highlighting the efficacy of ECE-LAMS,particularly in challenging cases which have failed endoscopic retrograde cholangio pancreatography.A clinical success rate of 91.0% underscores its impact on symptom alleviation,while a reasonably tolerable adverse event rate of 17.5% is observed.However,the 7.3% re-intervention rate stresses the need for post-procedural monitoring.Subgroup analyses validate consistent outcomes,bolstering the applicability of ECE-LAMS.These findings advocate for the adoption of ECELAMS as an appropriate approach for biliary palliation,urging further exploration in real-world clinical contexts.They offer valuable insights for optimizing interventions targeting malignant biliary obstruction management.

Safety and efficacy of Kaffes intraductal self-expanding metal stents in the management of post-liver transplant anastomotic strictures

BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on safety and duration for metal stents in this setting is scarce.Due to limited access to endoscopic retrograde cholan-giopancreatography(ERCP)during the coronavirus disease 2019 pandemic in our centre,there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy.This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents.METHODS Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query.Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records.The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months.Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for≤120 d or>120 d.RESULTS During the study period,a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course.In 33 ERCPs,the stent was removed or exchanged on a 3-month interval.No pancreatitis,perfor-ations or deaths occurred.Minor post-ERCP complications were similar between the 3-month(abdominal pain and intraductal migration)and 6-month(abdominal pain,septic shower and embedded stent)groups-6.1%vs 9.1%respectively,P=0.40.All strictures resolved at the end of the stenting course,but the stenting course was variable from 3 to 22 months.The recurrence rate for stenting courses lasting for up to 120 d was 71.4%and 21.4%for stenting courses of 121 d or over(P=0.03).There were 28 patients that were treated with a single ERCP with Kaffes,21 with removal after 120 d and 7 within 120 d.There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course(71.0%vs 10.0%,P=0.01).CONCLUSION Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures.

Pulmonary artery stent thrombosis and symptomatic pulmonary hypertension following COVID-19 infection in Alagille patient:A case report

BACKGROUND Alagille syndrome is a multisystem disease that results in various vascular anomalies,commonly involving the cardiac and pulmonary systems.To the best of our knowledge,there is no literature regarding the cardiovascular outcomes of these patients in association with coronavirus disease 2019(COVID-19).CASE SUMMARY A 34-year-old woman with a history of Alagille syndrome who underwent successful atrial septal defect with partial anomalous pulmonary veins and patent ductus arteriosus repair,as well as left pulmonary artery catheterization and stenting in childhood due to pulmonary stenosis.The patient was without any respiratory symptoms and was a dancer prior to contracting COVID-19.Several weeks after her COVID-19 infection,she developed left pulmonary artery stent thrombosis and subsequent symptomatic pulmonary hypertension.A treatment strategy of anticoagulation alongside pharmacological agents for pulmonary hypertension for 3 months followed by balloon pulmonary artery angioplasty to reopen the stenosis was unsuccessful.CONCLUSION In the era of COVID-19,patients with pulmonary vascular malformations and endovascular stents are at an increased risk for chronic thromboembolic disease.Patients may benefit from prophylactic antiplatelet or anticoagulation therapy.Stent thrombosis is a devastating phenomenon and should be treated urgently and aggressively with balloon pulmonary angioplasty,and/or a thrombolytic agent.

Research on the Status Quo and Optimization of Centralized Procurement of Coronary Stents

Objective To study the impact of the first national centralized procurement of coronary stents on patients’psychology,the economy of medical institutions,and the survival and development of the coronary stents industry,and to provide suggestions on perfecting procedures to better carry out the centralized procurement of coronary stents.Methods Literature analysis was used to investigate the results of the procurement of coronary stent in a province and a hospital.Results and Conclusion The centralized procurement of coronary stents has alleviated the economic pressure of patients,but it has many problems.Therefore,this paper proposes some suggestions,such as promoting the orderly development of the coronary stent industry,improving the evaluation link of the centralized procurement of coronary stents,adopting the accurate reporting model to ensure the quality of coronary stents and improving the standardization of clinical services.

Pancreatic stent improves the success rate of needle-knife papillotomy in patients with difficult biliary cannulation

BACKGROUND Needle-knife precut papillotomy(NKP)is typically performed freehand.However,it remains unclear whether pancreatic stent(PS)placement can improve the outcomes of NKP.AIM To explore whether PS placement improves the success rate of NKP in patients with difficult biliary cannulation.METHODS This single-center retrospective study included 190 patients who underwent NKP between January 2017 and December 2021 after failed conventional biliary cannulation.In cases with incidental pancreatic duct cannulation during conventional biliary cannulation,the decision for pre-NKP PS placement was made at the endoscopist's discretion.The primary outcome was the difference in the NKP success rate between patients with and without PS placement;the secondary outcome was the adverse event rate.RESULTS Among the 190 participants,82 received pre-NKP PS(PS-NKP group)whereas 108 did not[freehand or freehand NKP(FH-NKP)group].Post-NKP selective biliary cannulation was successful in 167(87.9%)patients,and the PS-NKP had a significantly higher success rate than the FH-NKP group(93.9%vs 83.3%,P=0.027).The overall adverse event rates were 7.3%and 11.1%in the PS-NKP and FH-NKP groups,respectively(P=0.493).A periampullary diverticulum(PAD)and significant intraoperative bleeding during NKP were independently associated with NKP failure;however,a pre-NKP PS was the only predictor of NKP success.Among the 44 participants with PADs,the PS-NKP group had a non-significantly higher NKP success rate than the FH-NKP group(87.5%and 65%,respectively;P=0.076).CONCLUSION PS significantly improved the success rate of NKP in patients with difficult biliary cannulation.

Association of stent thrombectomy and conventional treatment with neuroprotection, complications, anxiety, and depression in acute ischemic stroke patients

BACKGROUND Acute ischemic stroke(AIS)is an abrupt blood flow cessation to a specific brain region within a vascular zone,causing a subsequent decline in neurological capabilities.Stent thrombectomy is a recently established technique for treating AIS.It provides the benefits of being a relatively simple and safe procedure,capable of partially enhancing a patient’s condition.However,some patients may experience endothelial damage and recurrent thrombosis,with clinical outcomes that are not always satisfactory.Hence,the efficacy of this method remains unclear.AIM To survey the association of stent thrombectomy vs standard treatment with neurological function protection,complications,and short-term prognosis in patients diagnosed with AIS.METHODS This study assigned 90 patients with AIS to the observation and control groups(n=45 patients)from December 2020 to December 2022.Stent thrombectomy was conducted in the observation group,whereas routine treatment was provided to the control group.The study assessed the therapeutic outcomes of two groups,including a comparison of their neurological function,living ability,anxiety and depression status,plaque area,serum inflammatory factors,serum Smur100βprotein,neuron-specific enolase(NSE),homocysteine(Hcy),and vascular endo-thelial function.Additionally,the incidence of complications was calculated and analyzed for each group.RESULTS The total effective rate of treatment was 77.78%and 95.56%in the control and observation groups,respectively.After 8 weeks of treatment,the scores on the National Institutes of Health Stroke Scale,Hamilton Anxiety Scale,and Hamilton Depression Scale decreased remarkably;the Barthel index increased remarkably,with better improvement effects of the scores in the observation group(P<0.05);total cholesterol,triglyceride,C-reactive protein,and plaque area lessened remarkably,with fewer patients in the observation group(P<0.05);S-100βprotein,NSE,and Hcy levels lessened remarkably,with fewer patients in the observation group(P<0.05);serum vascular endothelial growth factor and nitric oxide synthase levels increased remarkably,whereas the endothelin-1 level decreased,with better improvement effect in the observation group(P<0.05).Complications occurred in 8.88%of patients in the observation group compared with 33.33%in the control group.CONCLUSION Stent thrombectomy appeared to provide more remarkable neuroprotective effects in patients with AIS compared to the intravenous thrombolysis regimen.Additionally,it has effectively improved the neurological function,daily activities,and vascular endothelial function of patients,while reducing the incidence of complications and improving short-term prognosis.

Composite bioabsorbable vascular stents via 3D bio-printing and electrospinning for treating stenotic vessels

A new type of vascular stent is designed for treating stenotic vessels. Aiming at overcoming the shortcomings of existing equipment and technology for preparing a bioabsorbable vascular stent （BVS）, a new method which combines 3D bio-printing and electrospinning to prepare the composite bioabsorbable vascular stent （CBVS） is proposed. The inner layer of the CBVS can be obtained through 3D bio- printing using poly-p-dioxanone （PPDO）. The thin nanofiber film that serves as the outer layer can be built through electrospinning using mixtures of chitosan-PVA （poly （vinyl alcohol））. Tests of mechanical properties show that the stent prepared through 3D bio-printing combined with electrospinning is better than that prepared through 3D bio- printing alone. Cells cultivated on the CBVS adhere and proliferate better due to the natural, biological chitosan in the outer layer. The proposed complex process and method can provide a good basis for preparing a controllable drug-carrying vascular stent. Overall, the CBVS can be a good candidate for treating stenotic vessels.

Stents for colorectal obstruction:Past,present,and future

Since the development of uncovered self-expanding metal stents(SEMS) in the 1990 s, endoscopic stents have evolved dramatically. Application of new materialsand new designs has expanded the indications for enteral SEMS. At present, enteral stents are considered the first-line modality for palliative care, and numerous types of enteral stents are under development for extended clinical usage, beyond a merely palliative purpose. Herein, we will discuss the current status and the future development of lower enteral stents.

Placement of prophylactic pancreatic stents to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis in high-risk patients: A meta-analysis

AIM: To assess the effectiveness of pancreatic stents for preventing pancreatitis in high-risk patients after endoscopic retrograde cholangiopancreatography (ERCP).

Advantages and disadvantages of biodegradable platforms in drug eluting stents

Coronary angioplasty with drug-eluting stent(DES)implantation is currently the most common stent procedure worldwide.Since the introduction of DES,coronary restenosis as well as the incidence of target vessel and target lesion revascularization have been significantly reduced.However,the incidence of very late stent thrombosis beyond the first year after stent deployment has more commonly been linked to DES than to baremetal stent(BMS)implantation.Several factors have been associated with very late stent thrombosis after DES implantation,such as delayed healing,inflammation,stent mal-apposition and endothelial dysfunction. Some of these adverse events were associated with the presence of durable polymers,which were essential to allow the elution of the immunosuppressive drug in the first DES designs.The introduction of erodable polymers in DES technology has provided the potential to complete the degradation of the polymer simultaneously or immediately after the release of the immunosuppressive drug,after which a BMS remains in place.Several DES designs with biodegradable(BIO)polymers have been introduced in preclinical and clinical studies, including randomized trials.In this review,we analyze the clinical results from 6 observational and randomized studies with BIO polymers and discuss advantages and disadvantages of this new technology.

Palliation of malignant esophageal obstruction and fistulas with self expandable metallic stents

AIM: To evaluate the efficacy of self expandable metallic stents (SEMS) in patients with malignant esophageal obstruction and fistulas. METHODS: SEMS were implanted in the presence of fluoroscopic guidance in patients suffering from advanced and non-resectable esophageal, cardiac and invasive lung cancer between 2002 and 2009. All procedures were performed under conscious sedation. All patients had esophagus obstruction and/or fistula. In all patients who required reintervention, recurrence of dysphagia, hemorrhage, and fistula formation were indications for further endoscopy. Patients' files were scanned retrospectively and the obtained data were analyzed using SPSS 13.0 for Windows. The χ 2 test was used for categorical data and was analysis of variance for noncategorical data. Patients' long-term survival was assessed using the Kaplan-Meier method. RESULTS: Stents were successfully implanted in 90 patients using fluoroscopic guidance. Reasons for stent implantation in these patients were esophageal stricture (77/90, 85.5%), external pressure (8/90, 8.8%) and tracheo-esophageal fistula (5/90, 5.5%). Dysphagia scores (mean ± SD) were 3.37 ± 0.52 before and 0.90 ± 0.43 after stent implantation (P = 0.002). Intermittent, nonmassive hemorrhage due to the erosion caused by the distal end of the stent in the stomach occurred in only one patient who received implementation at cardioesophageal junction. Mean survival following stenting was 134.14 d (95% confidence interval: 94.06-174.21).CONCLUSION: SEMS placement is safe and effective in the palliation of dysphagia in selected patients with malignant esophageal strictures.

Biodegradable stents in gastrointestinal endoscopy

Biodegradable stents(BDSs)are an attractive option to avoid ongoing dilation or surgery in patients with benign stenoses of the small and large intestines.The experience with the currently the only BDS for endoscopic placement,made of Poly-dioxanone,have shown promising results.However some aspects should be improved as are the fact that BDSs lose their radial force over time due to the degradable material,and that can cause stent-induced mucosal or parenchymal injury.This complication rate and modest clinical efficacy has to be carefully considered in individual patients prior to placement of BDSs.Otherwise,the price of these stents therefore it is nowadays an important limitation.

Lumen-apposing metal stents for malignant biliary obstruction: Is this the ultimate horizon of our experience?

In the last years, endoscopic ultrasonography (EUS) has evolved from a purely diagnostic technique to a more and more complex interventional procedure, with the possibility to perform several type of therapeutic interventions. Among these, EUS-guided biliary drainage (BD) is gaining popularity as a therapeutic approach after failed endoscopic retrograde cholangiopancreatography in distal malignant biliary obstruction (MBO), due to the avoidance of external drainage, a lower rate of adverse events and re-interventions, and lower costs compared to percutaneous trans-hepatic BD. Initially, devices created for luminal procedures (e.g., luminal biliary stents) have been adapted to the new trans-luminal EUSguided interventions, with predictable shortcomings in technical success, outcome and adverse events. More recently, new metal stents specifically designed for transluminal drainage, namely lumen-apposing metal stents (LAMS), have been made available for EUS-guided procedures. An electrocautery enhanced delivery system (EC-LAMS), which allows direct access of the delivery system to the target lumen, has subsequently simplified the classic multi-step procedure of EUS-guided drainages. EUS-BD using LAMS and ECLAMS has been demonstrated effective and safe, and currently seems one of the most performing techniques for EUS-BD. In this Review, we summarize the evolution of the EUS-BD in distal MBO, focusing on the novelty of LAMS and analyzing the unresolved questions about the possible role of EUS as the first therapeutic option to achieve BD in this setting of patients.

Temporary self-expanding metallic stents for achalasia: A prospective study with a long-term follow-up

AIM: To compare the efficacy of self-expanding metallic stents (SEMSs) for the long-term clinical treatment of achalasia. METHODS: Ninety achalasic patients were treated with a temporary SEMS with a diameter of 20 mm (n = 30, group A), 25 mm (n = 30, group B) or 30 mm (n = 30, group C). Data on clinical symptoms, complications and treatment outcomes were collected, and follow-up was made at 6 mo and at 1, 3-5, 5-8, 8-10 and > 10 years, postoperatively.RESULTS: Stent placement was successful in all patients. Although chest pain occurrence was high, stent migration was less in group C than in groups A and B. The clinical remission rate at 5-8, 8-10 and > 10 years in group C was higher than that in the other two groups. The treatment failure rate was lower in group C (13%) than in groups A (53%) and B (27%). SEMSs in group C resulted in reduced dysphagia scores and lowered esophageal sphincter pressures, as well as normal levels of barium height and width during all the follow-up time periods. Conversely, these parameters increased over time in groups A and B. The primary patency in group C was longer than in groups A and B. CONCLUSION: A temporary SEMS with a diameter of 30 mm is associated with a superior long-term clinical efficacy in the treatment of achalasia compared with a SEMS with a diameter of 20 mm or 25 mm.