Does potassium citrate administration change the type and composition of encrusted material on Double-J stent compared to primary stone?

Purpose

To evaluate the effect of potassium citrate administration on the composition of encrusted material on the ureteral stent after Double-J insertion.

Methods

We designed a randomized clinical trial for our study; 65 patients that underwent transurethral lithotripsy and Double-J stent insertion were included in the study after informed consent and divided into two groups. In the first group (33 patients) potassium citrate was prescribed after surgery till stent removal and the second group (32 patients) followed without prescribing this medication. After stent removal, encrusted materials on removed stents were analyzed then the type and composition of encrusted material compared with the primary stone that was removed.

Results

Our results revealed that the type and composition of primary stone and encrusted stone were similar in patients that do not receive potassium citrate (p-value of 0.073, 0.251 and 0.944 for calcium oxalate, uric acid, and calcium phosphate respectively). In patients that taking potassium citrate rate of calcium oxalate (p-value < 0.001) and uric acid (p-value < 0.001) material on encrusted stent significantly decreased compared with the non-intervention group.

Conclusion

Results of this study revealed that taking of potassium citrate after ureteral stent insertion significantly decreases the formation of calcium oxalate and uric acid encrusted material on Double-J stent so it could be recommended for prevention of stent encrustation in patients that primary stone analysis are calcium oxalate and uric acid stone.

Comparison Between Lumen-Apposing Metal Stents and Plastic Stents in Endoscopic Ultrasound-Guided Drainage of Pancreatic Fluid Collection: A Meta-analysis and Systematic Review

OBJECTIVES

This study aimed to explore efficacy and safety between LAMSs (lumen-apposing metal stents) and DPPSs (double-pigtail plastic stents) in endoscopic ultrasound-guided drainage for pancreatic fluid collections.

METHODS

Electronic databases were searched to identify relevant studies published until July 20, 2020.

RESULTS

Fifteen studies were identified in this study. Endoscopic ultrasound-guided drainage with LAMS has higher clinical success (90.01% vs 82.56%) (odds ratio [OR], 2.44; 95% confidence interval [CI], 1.79-3.33; P < 0.00001), less recurrence (OR, 0.44; 95% CI, 0.29-0.68; P = 0.0002), and fewer additional interventions (OR, 0.34; 95% CI, 0.211-0.55; P < 0.001). There was no significant difference between LAMS and DPPS in technical success (97.45% vs 97.38%) (OR, 0.92; 95% CI, 0.50-1.70; P = 0.80), adverse events (OR, 0.92; 95% CI, 0.41-2.09; P = 0.84), stent-related adverse events (OR, 0.78; 95% CI, 0.39-1.54; P = 0.47), and bleeding (OR, 1.47; 95% CI, 0.57-3.28; P = 0.42). Lumen-apposing metal stents have slightly more perforations (OR, 7.10; 95% CI, 1.22-41.30; P = 0.03) in studies of walled-off necrosis.

CONCLUSIONS

Lumen-apposing metal stents have the advantage of higher clinical success, less recurrence, and fewer additional interventions. However, LAMS may increase perforation for walled-off necrosis.

Covered vs bare stent for distal malignant biliary obstruction due to primary common biliary cancer

This study was designed as a means of comparing the clinical efficacy and long-term outcomes of covered vs bare stent insertion as a treatment for distal malignant biliary obstruction (DMBO) caused by primary common biliary cancer (PCBC).This retrospective study was designed using data collected between January 2012 and December 2019 to assess the short- and long-term outcomes in patients with DMBO caused by PCBC treated by inserting either bare or covered stents were compared.Ninety two patients with DMBO caused by PCBC were divided between bare (n = 51) or covered (n = 41) stent groups. Technical success rates in both groups were 100%. Clinical success of bare vs covered stent use were 96.1% and 97.6% (P = 1.00). Stent dysfunction was seen in 17 and 6 patients in the bare and covered stent groups, respectively (P = .04). The median stent patency for bare and covered stents was 177 and 195 days, respectively (P = .51). The median survival was 188 and 200 days in the bare and covered stent groups, respectively (P = .85).For patients with DMBO caused by PCBC, using bare vs covered stents yields similar clinical efficacy and long term outcomes.

[Influence of traditional double-J stent versus Polaris loop stent on the quality of life and erectile function of young and middle-aged men after ureteral laser lithotripsy]

OBJECTIVE

To investigate the impact of two different ureteral stents on the quality of life and erectile function of young and middle-aged men after ureteral laser lithotripsy.

METHODS

A total of 118 male patients aged 22－45 years underwent ureteral laser lithotripsy followed by indwelling of the traditional double-J stent (the DJS group, n = 60) or Polaris loop stent (the PLS group, n = 58). We obtained the general information, intra- and post-operative clinical data, and scores on QOL, IPSS, Visual Analogue Scale (VAS) and IIEF, and compared them between the two groups of patients.

RESULTS

There were no statistically significant differences in the body mass index, height, stone diameter, hydronephrosis degree, operation time, intra-operative adverse events, or post-operative stenting time between the two groups of patients. The PLS outperformed the DJS group in such clinical indexes as inflammation markers, lower urinary tract symptoms (LUTS), backache at urination, and QOL, IPSS and VAS scores during stenting at 4 weeks after operation(P < 0.05). The IIEF scores of the PLS and DJS groups were 8.44 ± 2.10 vs 12.50 ± 1.78 (P = 0.003) at 2 weeks, 8.65 ± 1.90 vs 13.42 ± 1.88 (P = 0.002) at 4 weeks, and 13.57 ± 1.01 vs 17.38 ± 2.47 (P = 0.003) at 6 weeks after operation, with no statistically significant difference between the two groups at 8 weeks.

CONCLUSIONS

Ureteral stenting affects the quality of life and erectile function of young and middle-aged male patients after ureteral laser lithotripsy. The Polaris loop stent affects less the quality of life and erectile function of the patients than the traditional double-J stent during postoperative stenting.

Percutaneous stenting and chemotherapy for unresectable pancreatic cancer: Comparison of irradiation stents vs conventional metal stents

OBJECTIVES

Percutaneous stenting is a palliative method to relieve obstructive jaundice caused by unresectable pancreatic carcinoma. In this study, we aimed to compare the safety and efficacy of irradiation stents and conventional metal stents.

METHODS

A total of 32 patients who received irradiation stents or conventional metal stents to treat obstructive jaundice caused by locally advanced pancreatic cancer were included in this retrospective study. Chemotherapy using gemcitabine was performed after jaundice subsided. Stent patency, technical success, survival, and complications were compared between groups.

RESULTS

Seventeen patients were enrolled in the irradiation stent group (ISG), and 15 patients were enrolled in the uncovered stent group (USG). Median and mean stent patency time were 9.8 months (95% CI, 7.682-11.981) and 9.506 months (95% CI, 8.0-11.012) in the ISG, respectively, vs 8.8 months (95% CI, 6.528-11.072) and 7.62 months (95% CI, 5.917-9.323) in the USG, respectively (P = 0.019). Median and mean overall survival were 10.4 months (95% CI, 8.383-12.417) and 9.953 months (95% CI, 8.408-11.498), respectively, in the ISG vs 9.7 months (95% CI, 7.901-11.499) and 8.14 months (95% CI, 6.44-9.84), respectively, in the USG (P = 0.027).

CONCLUSIONS

Irradiation stents extend stent patency and overall survival compared with conventional biliary stents for the treatment of pancreatic carcinoma complicated by obstructive jaundice. Irradiation stents combined with chemotherapy may be a better choice for the treatment of obstructive jaundice caused by unresectable pancreatic carcinoma.

Endoscopic, Single-Session Management of Encrusted, Forgotten Ureteral Stents

Background and Objectives: Remained or forgotten ureteral double-J stents may cause serious complications. Removing of an encrusted, forgotten stent can be challenging. We present our experience with heavily encrusted ureteral stents and discuss the endourologic treatment options as well as their effectivity. Materials and Methods: Eleven men and six women (mean 48.58 ± 14.48 years of age) with 18 encrusted forgotten stents (mean 16.4 ± 13.25 months of indwelling) were treated at our clinic. All patients underwent the operation after negative urine cultures were obtained. Their medical records were retrospectively reviewed and analyzed in terms of number of interventions required to remove the stent, operation time, complications, hospital stay and stone-free rate. Results: According to the Forgotten-Encrusted-Calcified (FECal) classification, the most common form of stent encrustation was grade III (64.7%) and 17.6% of the stents were fragmented. Four of 17 patients were initially treated with extracorporeal shock-wave lithotripsy. The patients required a mean of two endoscopic interventions for removing the encrusted stent and all stents were removed endoscopically in a single session. The mean operating time was 63.3 ± 41.8 minutes. Cystolithotripsy followed by ureteroscopy was the most common intervention (41.1%). Of the 17 patients, peroperative and postoperative complications were Clavien grade I in two, grade II in two and grade IIIb in one. The mean hospital stay was 1.3 ± 0.99 days. All patients were stone-free after a month of stent removal. Conclusions: The endourological removal of the encrusted forgotten stents in a single session is feasible and effective with a minimal morbidity. The treatment strategy should be to minimize the number of interventions.

Metallic Ureteric Stents in Malignant Ureteric Obstruction: A Systematic Review

The effectiveness of metallic stents in the management of malignant ureteric obstruction is unclear. This systematic review evaluates the use of 4 commercially available metallic stents (Resonance, Memokath 051, Uventa, and Allium URS). Twenty-one studies met eligibility criteria. Overall success rates ranged from 88% for the Allium stent to 65% for Memokath 051. Resonance demonstrated the lowest migration rate (1%). Uventa had the lowest obstruction rate (6%). Metallic ureteric stents offer a viable alternative in the management of malignant ureteric obstruction. Further high quality studies are required to assess cost effectiveness and refine specific indications based on etiology and level of the ureteric obstruction.

[Vascular stents: Approaches used to increase their clinical efficacy]

Using stents for endovascular restoration of blood flow made a revolution in vascular surgery, however, despite numerous variants of stents presented on the pharmacological market, there are no stents which would completely solve the problem of restenosis in the area of stent placement. In order to decrease growth of the neointima of the stented portions of vessels, stents coated with cytostatic and cytotoxic agents were worked out. To optimize the rate of drug release it was suggested to apply them in a mixture with biodegradable or biostable polymers. Placement of drug-eluting stents in a combination with dual antiplatelet therapy made it possible to decrease frequency of restenosis and reocclusion of the restored vascular lumen in patients, however it did not solve the problem of the development of thromboses and neointimal hyperplasia in the remote postoperative period. The article provides an overview of various modifications of vascular stents, clinical studies of stents of various manufacturers, as well as modern developments in manufacturing polymer/drug coatings and methods of applying them onto the stent. This is followed by analyzing the contribution of coatings to clinical efficacy of stents and prospects of increasing efficacy of vascular stents.

Clinical, humanistic, and economic outcomes between drug-eluting stent (DES) and bare metal stent (BMS): 18-month follow-up study

BACKGROUND

Percutaneous coronary intervention (PCI) is one of the most performed interventions for ischemic heart diseases. In Hong Kong, the total number of patient discharges and deaths for ischemic heart diseases in 2009 was 33,363, including 4,360 deaths. There are over 5,000 cases of PCI yearly. This study aimed to compare clinical, economic, and humanistic outcomes among patients receiving drug-eluting stent (DES) or bare metal stent (BMS) in Hong Kong.

METHODS

Patients who received stent implantation between September 15, 2009 and October 11, 2010 in Prince of Wales Hospital, Hong Kong, were recruited and followed for 18 months. Occurrence of major adverse cardiac events (cardiac death, non-fatal MI, TLR and TVR) was employed as the clinical outcome measurements. Improvement in quality-of-life by stent interventions was measured as quality-adjusted life-year (QALY). EQ-5D questionnaire was adopted to assess the QALY gained. Cost-utility analysis and cost-effectiveness analysis for BMS and DES were employed as the economic outcome measurement.

RESULTS

Six hundred and eighty-four patients (DES = 402; BMS = 282) were included. From 0-18 months, TLR rate (2.7% vs 3.5%, p = .549) and TVR rate (3.7% vs 6.4%, p = .111) were lower in the DES group, but without statistical significance. EQ VAS (71.06 ± 14.56 vs 71.07 ± 16.57, p = .998) and utility score (0.81 ± 0.17 vs 0.78 ± 0.16, p = .162) were comparable between DES and BMS group. Overall, the cost per QALY gained was HKD + 1,178,100 and ICER was HKD + 187,000 (1USD = 7.8 HKD).

CONCLUSIONS

No significant difference in TVR, TLR rates, EQ VAS, and utility score was found between the DES and BMS group. The higher cost of index procedure for the DES group was found to be partly offset by reduced cost of follow-up, offering cost-effectiveness in ACS patients, predominantly in STEMI patients. DES was recommended for STEMI patients.

Comparison of Drug-Eluting Stents With Bare-Metal Stents for PCI of Saphenous Vein Graft Lesions: Systematic Review and Meta-Analysis

BACKGROUND

The superiority of drug-eluting stent (DES) implantation over bare-metal stent (BMS) implantation in saphenous vein graft (SVG) lesions is controversial, with significant heterogeneity demonstrated in the literature.

METHODS

A study search was conducted from January 2003 to October 2015, and identified four randomized controlled trials (RCTs) and 35 observational studies comparing DES vs BMS in SVG interventions. Clinical endpoint data were abstracted and analyzed by combining the odds ratios (ORs) of individual studies into a pooled OR using a random-effects model.

RESULTS

The meta-analysis included 39,213 patients in the DES group and 26,461 patients in the BMS group. Patients who underwent percutaneous coronary intervention with DES had lower major adverse cardiovascular event (MACE) rate (OR, 0.63; 95% confidence interval [CI], 0.54-0.74; P<.001), lower all-cause mortality rate (OR, 0.76; 95% CI, 0.69-0.84; P<.001), lower target-vessel revascularization (TVR) rate (OR, 0.70; 95% CI, 0.57-0.86; P<.001), and lower target-lesion revascularization (TLR) rate (OR, 0.64; 95% CI, 0.50-0.84; P<.01), with no difference in stent thrombosis (OR, 0.90; 95% CI, 0.61-1.32; P=.58). There was no significant reduction in myocardial infarction (MI) in the DES group compared with the BMS group (OR, 0.87; 95% CI, 0.73-1.04; P=.13). Benefits were sustained at long-term follow-up of 36 months without an increased risk of early and/or late stent thrombosis. The observed benefit for MACE was only seen in observational studies (OR, 0.63; 95% CI, 0.53-0.75; P<.001) with no benefit in RCTs (OR, 0.53; 95% CI, 0.20-1.40; P=.20).

CONCLUSIONS

The results suggest that patients with DES in comparison with BMS implantation for PCI to SVG lesions had lower MACE, all-cause mortality, and TVR rates, without a significant reduction in MI and TLR.

Outcomes of Endovascular AAA Repair in Patients with Hostile Neck Anatomy Using Adjunctive Balloon-Expandable Stents

Hostile neck anatomy remains the predominant reason that patients are denied endovascular aneurysm repair (EVAR). We reviewed our experience of EVAR with use of prophylactic adjunctive proximal balloon-expandable stents in patients with hostile neck anatomy and adjunctive proximal balloon-expandable stents in patients with type I endoleaks. Of 140 patients who underwent EVAR between 2000 and 2004, we reviewed data for 19 patients in whom we used proximal balloon-expandable stents. By high-resolution computed tomography scan or angiography, hostile neck anatomy was classified as length <15 mm, neck diameters = 26 mm, circumferential thrombus at the proximal neck, angulated neck =60 degrees, and neck bulge or reverse taper necks. Patients were considered to have hostile anatomy if they met 1 or more of the above-cited criteria. All patients underwent AAA repair with commercially available endograft systems, Zenith (Cook, Bloomington, IN) and AneuRx (Medtronic/AVE, Minneapolis, MN). Balloon-expandable stents utilized included Cordis-Palmaz stents (17/19) and eV3 Max stents (2/19). Stents were deployed in the proximal graft with transrenal extension. AneuRx (18/19) and Zenith (1/19) endografts were used in all of the patients. Of the 19 patients, 15 had prophylactic stent placement for known hostile neck anatomy and 4 patients had stent placement for type I endoleak. Assisted primary technical success was achieved in all patients. Three patients had maldeployment of the endograft or proximal stent requiring additional endovascular interventions at the time of surgery. No endografts were deployed too low requiring stent placement. Procedure-related complications occurred in 2 of 19 patients. These included 1 operative death secondary to pneumonia and 1 patient who developed progressive renal failure. Short-term clinical success was achieved in 17 of 19 patients. Two patients required secondary interventions, 1 due to device migration with secondary conversion to open repair, and an endoleak, which, on angiogram, was a large type II endoleak successfully treated with coiling of the inferior mesenteric artery. One patient was observed to have a type II endoleak with no associated aneurysm enlargement. Short-term results suggest the use of prophylactic adjunctive balloon-expandable stents may decrease the incidence of secondary interventions related to hostile neck anatomy when used as an adjunctive measure with EVAR. Based on our experience, we feel EVAR may be offered to an expanded patient population with hostile neck anatomy with use of prophylactic balloon-expandable stents.

Medical Devices; Gastroenterology-Urology Devices; Classification of the Metallic Biliary Stent System for Benign Strictures. Final order

The Food and Drug Administration (FDA) is classifying the metallic biliary stent system for benign strictures into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the metallic biliary stent system for benign strictures' classification. The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

Stents for the prevention of pancreatic fistula following pancreaticoduodenectomy

BACKGROUND

Several studies have demonstrated that the use of pancreatic duct stents following pancreaticoduodenectomy is associated with a lower risk of pancreatic fistula. However, to date there is a lack of accord in the literature on whether the use of stents is beneficial and, if so, whether internal or external stenting, with or without replacement, is preferable. This is an update of a systematic review.

OBJECTIVES

To determine the efficacy of pancreatic stents in preventing pancreatic fistula after pancreaticoduodenectomy.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Web of Science, and four major Chinese biomedical databases up to November 2015. We also searched several major trials registers.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing the use of stents (either internal or external) versus no stents, and comparing internal stents versus external stents, replacement versus no replacement following pancreaticoduodenectomy.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data. The outcomes studied were incidence of pancreatic fistula, need for reoperation, length of hospital stay, overall complications, and in-hospital mortality. We showed the results as risk ratio (RR) or mean difference (MD), with 95% confidence interval (CI). We assessed the quality of evidence using GRADE (http://www.gradeworkinggroup.org/).

MAIN RESULTS

We included eight studies (1018 participants). The average age of the participants ranged from 56 to 68 years. Most of the studies were conducted in single centers in Japan (four studies), China (two studies), France (one study), and the USA (one study). The risk of bias was low or unclear for most domains across the studies. Stents versus no stentsThe effect of stents on reducing pancreatic fistula in people undergoing pancreaticoduodenectomy was uncertain due to the low quality of the evidence (RR 0.67, 95% CI 0.39 to 1.14; 605 participants; 4 studies). The risk of in-hospital mortality was 3% in people who did receive stents compared with 2% (95% CI 1% to 6%) in people who had stents (RR 0.73, 0.28 to 1.94; 605 participants; 4 studies; moderate-quality evidence). The effect of stents on reoperation was uncertain due to wide confidence intervals (RR 0.67, 0.36 to 1.22; 512 participants; 3 studies; moderate-quality evidence). We found moderate-quality evidence that using stents reduces total hospital stay by just under four days (mean difference (MD) -3.68, 95% CI -6.52 to -0.84; 605 participants; 4 studies). The risk of delayed gastric emptying, wound infection, and intra-abdominal abscess was uncertain (gastric emptying: RR 0.75, 95% CI 0.24 to 2.35; moderate-quality evidence) (wound infection: RR 0.73, 95% CI 0.40 to 1.32; moderate-quality evidence) (abscess: RR 1.38, 0.49 to 3.85; low-quality evidence). Subgroup analysis by type of stent provided limited evidence that external stents lead to lower risk of fistula compared with internal stents. External versus internal stentsThe effect of external stents on the risk of pancreatic fistula, reoperation, delayed gastric emptying, and intra-abdominal abscess compared with internal stents was uncertain due to low-quality evidence (fistula: RR 1.44, 0.94 to 2.21; 362 participants; 3 studies) (reoperation: RR 2.02, 95% CI 0.38 to 10.79; 319 participants; 3 studies) (gastric emptying: RR 1.65, 0.66 to 4.09; 362 participants; 3 studies) (abscess: RR 1.91, 95% CI 0.80 to 4.58; 362 participants; 3 studies). The rate of in-hospital mortality was lower in studies comparing internal and external stents than in those comparing stents with no stents. One death occurred in the external-stent group (RR 0.33, 0.01 to 7.99; low-quality evidence). There were no cases of pancreatitis in participants who had internal stents compared with three in those who had external stents (RR 0.15, 0.01 to 2.73; low-quality evidence). The difference between internal and external stents on total hospital stay was uncertain due to the wide confidence intervals around the average effect of 1.7 days fewer with internal stents (9.18 days fewer to 5.84 days longer; 262 participants; 2 studies; low-quality evidence). The analysis of wound infection could not exclude a protective effect with either approach (RR 1.41, 0.44 to 4.48; 319 participants; 2 studies; moderate-quality evidence). Operative replacement of pancreatic juice versus not replacing pancreatic juice There was insufficient evidence available from a small trial to ascertain the effect of replacing pancreatic juice.

AUTHORS' CONCLUSIONS

This systematic review has identified limited evidence on the effects of stents. We have not been able to identify convincing direct evidence of superiority of external over internal stents. We found a limited number of RCTs with small sample sizes. Further RCTs on the use of stents after pancreaticoduodenectomy are warranted.

[Results of Percutaneous Coronary Intervention in Elderly Diabetic Patients]

OBJECTIVE

Our aim was to compare results of the percutaneous coronary intervention (PCI) with drug elutingstent (DES) and bare metal stent (BMS) in older patients with coronary heart disease (CHD) and diabetes mellitus (DM) type 2.

METHODS

Patients (> 65 years) with DM type 2 were divided into two groups: the 1st group--58 patients after PCI with DES, the 2nd group--62 patients after PCI with BMS. The average follow-up period was 32.6 ± 8.0 months. The end-points of the study were death, non-fatal myocardial infarction and restenosis of the target stenosis.

RESULTS

Endovascular treatment of patients older than 65 years with DM is highly effective and safe despite the complexity of coronary lesions. There are no significant differences in the rate of early (hospital) complications in two groups. Also, we did notfind differences in three-year mortality between the groups. But the incidence of myocardial infarction in the groups with DES and BMS was 9% and 18% respectively (p = 0.039). Major adverse cardiovascular events (death, myocardial infarction and restenosis of the target stenosis) frequency was also lower in the group with DES compared to BMS (36% and 61% respectively, p = 0.001).

CONCLUSION

Endovascular treatment of patients older than 65 years with DM type 2 is a highly effective and safe method despite the complexity of coronary lesions. PCI with DES compared to BMS in older patients with DM is associated with improvement of medium-term results and decreases the number of cardiovascular events.

Stent graft types for endovascular repair of abdominal aortic aneurysms

BACKGROUND

The UK prevalence of abdominal aortic aneurysm (AAA) is estimated at 4.9% in over 65-year olds. Progressive and unpredictable enlargement can lead to rupture. Endovascular repair of AAAs involves a stent graft system being introduced via the femoral artery and manipulated within the aorta under radiological guidance. Following endograft deployment, a seal is formed at the proximal and distal landing zones to exclude the aneurysm sac from the circulation. With the increasing popularity of endovascular repair there has been an increase in the number of commercially available stent graft designs on the market. This is an update of the review first published in 2013.

OBJECTIVES

This review aimed to assess the different stent graft types for endovascular repair of AAA.

SEARCH METHODS

The Cochrane Vascular Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched February 2015) and the Cochrane Register of Studies (2015, Issue 1). Trial databases were searched by the TSC for details of ongoing and unpublished studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) of stent graft types in the repair of AAAs were sought without language restriction and in consultation with the Cochrane Vascular Group TSC.

DATA COLLECTION AND ANALYSIS

We planned to conduct data collection and analysis in accordance with the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

No studies were identified that met the inclusion criteria. It was not possible to review the quality of the evidence in the absence of studies eligible for inclusion in the review.

AUTHORS' CONCLUSIONS

Unfortunately, no data exist regarding direct comparisons of the performance of different stent graft types. High quality randomised controlled trials evaluating stent graft types in abdominal endovascular aneurysm repair are required.

Stent graft types for endovascular repair of thoracic aortic aneurysms

BACKGROUND

The UK prevalence of thoracic aneurysm is estimated at 10.4 per 100,000 person-years. Progressive and unpredictable enlargement can lead to rupture. Endovascular repair of thoracic aortic aneurysms involves a stent graft system being introduced via the femoral artery and manipulated within the aorta under radiological guidance. Following endograft deployment, a seal is formed at the proximal and distal landing zones to exclude the aneurysm sac from the circulation. With the increasing popularity of endovascular repair there has been an increase in the number of commercially available stent graft designs on the market. This is an update of the review first published in 2013.

OBJECTIVES

This review aimed to assess the different stent graft types for endovascular repair of thoracic aortic aneurysms.

SEARCH METHODS

The Cochrane Vascular Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched February 2015) and the Cochrane Register of Studies CENTRAL (2015, Issue 1). Trial databases were searched by the TSC for details of ongoing and unpublished studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) of stent graft types in the repair of thoracic aortic aneurysms were sought without language restriction.

DATA COLLECTION AND ANALYSIS

Data collection and analysis was conducted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

No studies were identified that met the inclusion criteria. It was not possible to assess the quality of the evidence in the absence of studies eligible for inclusion in the review.

AUTHORS' CONCLUSIONS

Unfortunately, no data exist regarding direct comparisons of the performance of different stent graft types. High quality RCTs evaluating stent graft types in thoracic endovascular aneurysm repair are required.

[Results of endovascular treatment of abdominal aortic aneurysms]

OBJECTIVE

Studying the results of endovascular prosthetic repair in patients with abdominal aortic aneurysms.

MATERIAL AND METHODS

A retrospective study of 34 elderly and aged patients (mean age 67.4±1.24 years) with severe concomitant pathology and the risk of Euroscore averagely amounting to 13.16±0.19, subjected to endoprosthetic repair for the presence of AAA.

RESULTS

In all 34 cases we obtained good immediate results of endoprosthetic repair of the infrarenal portion of the abdominal aorta: positioning of stent grafts was adequate, expansion complete, with no sign of endoleak. Hospital lethality rate was 0%. The intra- and postoperative periods were not accompanied by the development of neither cardiological nor neurological complications. Analysing by the McNemar criterion showed that there was a statistically significant trend towards elevation of leukocytosis and ESR after surgery (p=0.074), and for other indices the shifts were statistically insignificant or absent. Since no signs of an inflammatory process were revealed, in all cases the postoperative wounds healed with fist intension, the alterations in the blood formula were associated with resorption of thrombotic masses in the paraprosthesis space.

CONCLUSION

In all cases, implantation of the stent graft resulted in achieving the main objective, i. e. adequate isolation of the aneurysmatic sac in AAA. Dynamic follow up did not reveal any cases of stent graft dislocation, aneurysm rupture, thrombosis of endograft branches, or type 1a leaks.

Thoracic endovascular aortic repair: are we approaching total endovascular solutions for thoracic aortic disease?

Thoracic endovascular aortic repair (TEVAR) has become an attractive alternative treatment option for thoracic aortic disease. New devices and advanced image-guided procedures are continuously expanding the indications. This article focuses on currently available endovascular solutions for thoracic aortic disease and future 'all endovascular' directions of TEVAR. Currently available endovascular solutions, such as hybrid operations, chimney stent grafting and transapical stent graft deployment, for ascending aortic pathologies are presented. Additionally, the impact of upcoming new technologies, such as endovascular treatment of Stanford Type A dissections of the ascending aorta, is elaborated. With improving device technology, diverse available stent grafts and imaging modalities, TEVAR has become safer and holds promising potential to expand treatment options, especially for the ascending aorta and the aortic arch.

Medical devices; gastroenterology-urology devices; classification of pancreatic drainage stent and delivery system. Final order

The Food and Drug Administration (FDA) is classifying the pancreatic drainage stent and delivery system into class II (special controls). The special controls that will apply to the device are identified in this order, and will be part of the codified language for the pancreatic drainage stent and delivery system classification. The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

Understanding urinary conditioning film components on ureteral stents: profiling protein components and evaluating their role in bacterial colonization

Ureteral stents are fraught with problems. A conditioning film attaches to the stent surface within hours of implantation; however, differences between stent types and their role in promoting encrustation and bacterial adhesion and colonization remain to be elucidated. The present work shows that the most common components do not differ between stent types or patients with the same indwelling stent, and contain components that may drive stent encrustation. Furthermore, unlike what was previously thought, the presence of a conditioning film does not increase bacterial adhesion and colonization of stents by uropathogens. Genitourinary cytokeratins are implicated in playing a significant role in conditioning film formation. Overall, stent biomaterial design to date has been unsuccessful in discovering an ideal coating to prevent encrustation and bacterial adhesion. This current study elucidates a more global understanding of urinary conditioning film components. It also supports specific focus on the importance of physical characteristics of the stent and how they can prevent encrustation and bacterial adhesion.

Unprotected left main PCI: status report 2013

Unprotected left main coronary artery (ULMCA) disease is seen in 4% of patients who undergo angiography. Though coronary artery bypass graft surgery has traditionally been the preferred approach to revascularization, recent major society guidelines support the use of percutaneous coronary intervention (PCI) in properly selected patients. This article provides an overview of recent studies evaluating the efficacy of ULMCA PCI and looking at contemporary approaches to the evaluation and percutaneous treatment of ULMCA disease. The ongoing EXCEL trial will help elucidate the role of ULMCA PCI in the treatment of left main disease compared with coronary artery bypass graft surgery.

Stents for the prevention of pancreatic fistula following pancreaticoduodenectomy

BACKGROUND

Several studies have demonstrated that the use of pancreatic duct stents following pancreaticoduodenectomy is associated with a lower risk of pancreatic fistula. However, to date, there is a lack of accord in the literature on whether the use of stents is beneficial and, if so, whether internal or external stenting is preferable.

OBJECTIVES

To determine the efficacy of pancreatic stents in preventing pancreatic fistula after pancreaticoduodenectomy.

SEARCH METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, ISI Web of Science and four major Chinese biomedical databases were searched up to February 2011. We also searched four major trials registers.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing the use of stents (either internal or external) versus no stents, and comparing internal stents versus external stents following pancreaticoduodenectomy.

DATA COLLECTION AND ANALYSIS

Two authors extracted the data independently. The outcomes studied were incidence of pancreatic fistula, need for reoperation, length of hospital stay, overall complications, and in-hospital mortality. The results were shown as relative risk (RR) with 95% confidence interval (CI).

MAIN RESULTS

A total of 656 patients were included in the systematic review. Overall, the use of stents (both external and internal) was not associated with a statistically significant change in any of the studied outcomes. In a subgroup analysis, it was found that the use of external, but not internal, stents is associated with a significant reduction in the incidence of pancreatic fistulae (RR 0.33; 95% CI 0.11 to 0.98, P = 0.04), the incidence of complications (RR 0.48; 95% CI 0.25 to 0.92, P = 0.03) and length of hospital stay (RR -0.57; 95% CI -0.94 to -0.21, P = 0.002). In RCTs on the use of internal versus external stents, no statistically significant difference was found in terms of any of the studied outcomes.

AUTHORS' CONCLUSIONS

This systematic review suggests that the use of external stents following pancreaticoduodenectomy may be beneficial. However, only a limited number of RCTs with rather small sample sizes were available. Further RCTs on the use of stents after pancreaticoduodenectomy are warranted.

Biodegradable stents for caustic esophageal strictures: a new therapeutic approach

The treatment of caustic esophageal strictures is a challenging topic. Although traditional therapies have limited efficacy, most of these patients eventually require surgery. Biodegradable (BD) stents are newly designed stents for benign conditions. This is a retrospective case series of seven patients with caustic esophageal stricture. BD esophageal stents were inserted for palliation of dysphagia. The position of the stent was checked at 1, 4, 8, 12 16, 20, and 24 weeks and at the end of follow-up period. The follow-up period was 60 ± 23 (36-102) weeks. Complete dissolution of the stent occurred at 16 ± 4 (12-20) weeks. Three patients had partial/complete relief of dysphagia. The remaining four patients experienced tissue hyperplasia at the edges of the stent and required serial dilations. At the end of follow-up, all patients had partial or complete relief of dysphagia. Although BD stents have some efficiency, tissue hyperplasia is the main limiting factor. Further randomized trials are needed to determine efficiency of BD stents for caustic damage.

Stent graft types for endovascular repair of abdominal aortic aneurysms

BACKGROUND

The UK prevalence of abdominal aortic aneurysm (AAA) is estimated at 4.9% in over 65-year olds. Progressive and unpredictable enlargement can lead to rupture. Endovascular repair of AAAs involves a stent graft system being introduced via the femoral artery and manipulated within the aorta under radiological guidance. Following endograft deployment, a seal is formed at the proximal and distal landing zones to exclude the aneurysm sac from the circulation. With the increasing popularity of endovascular repair there has been an increase in the number of commercially available stent graft designs on the market.

OBJECTIVES

This review aimed to assess the different stent graft types for endovascular repair of AAA.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched November 2012) and CENTRAL (2012, Issue 10). Trial databases were searched by the TSC for details of ongoing and unpublished studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) of stent graft types in the repair of AAAs were sought without language restriction and in consultation with the Peripheral Vascular Disease Group TSC.

DATA COLLECTION AND ANALYSIS

We planned to conduct data collection and analysis in accordance with the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

No studies were identified that met the inclusion criteria.

AUTHORS' CONCLUSIONS

Unfortunately, no data exist regarding direct comparisons of the performance of different stent graft types. Therefore, this review cannot recommend guidance to clinicians in their selection of stent graft types. High quality randomised controlled trials evaluating stent graft types in abdominal endovascular aneurysm repair are required.

Stent graft types for endovascular repair of thoracic aortic aneurysms

BACKGROUND

The UK prevalence of thoracic aneurysm is estimated at 10.4 per 100,000 person-years. Progressive and unpredictable enlargement can lead to rupture. Endovascular repair of thoracic aortic aneurysms involves a stent graft system being introduced via the femoral artery and manipulated within the aorta under radiological guidance. Following endograft deployment, a seal is formed at the proximal and distal landing zones to exclude the aneurysm sac from the circulation. With the increasing popularity of endovascular repair there has been an increase in the number of commercially available stent graft designs on the market.

OBJECTIVES

This review aimed to assess the different stent graft types for endovascular repair of thoracic aortic aneurysms.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched November 2012) and CENTRAL (2012, Issue 11). Trial databases were searched by the TSC for details of ongoing and unpublished studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) of stent graft types in the repair of thoracic aortic aneurysms were sought without language restriction.

DATA COLLECTION AND ANALYSIS

Data collection and analysis was conducted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

No studies were identified that met the inclusion criteria.

AUTHORS' CONCLUSIONS

Unfortunately, no data exist regarding direct comparisons of the performance of different stent graft types. Therefore, this review cannot recommend guidance to clinicians in their selection of stent graft types. High quality RCTs evaluating stent graft types in thoracic endovascular aneurysm repair are required.

[Choice of tools for stenting the left coronary artery trunk: a whim or a need?]

OBJECTIVE

To study the results of stenting the left coronary artery trunk and to determine the possibility of using Empira dilatation balloon catheters for kissing dilatation.

SUBJECT AND METHODS

The left coronary artery trunk was stented in 47 patients, which constituted 1.39% of the total number of the stented patients. Bifurcation stenting was performed in 48.9%. T and crush stenting procedures were used in 4 and 2 patients, respectively. Stenting of the left coronary artery trunk with transition to the orifice of the anterior interventricular artery or the circumflex artery was carried out in 12 and 5 patients, respectively.

RESULTS

The angiographic success rate was 100%; there were no fatal outcomes. After endovascular treatment, 20 (42.5%) patients belonged to Functional Class (FC) 0-I angina; 24 (51.1%) and 3 (6.4%) were diagnosed with FC II and III, respectively.

CONCLUSION

It was ascertained that it was expedient to use the Empira dilatation balloon catheters for kissing dilatation. The left coronary artery trunk can be successfully stented if the patent is carefully prepared for the intervention.

Comparison of the influence of plastic and fully covered metal biliary stents on the accuracy of EUS-FNA for the diagnosis of pancreatic cancer

BACKGROUND AND STUDY AIMS

Prior studies have reported that the presence of prior biliary stent may interfere with EUS visualization of pancreatic tumors. We aimed to compare the influence of the biliary plastic and fully covered self-expanding metal stents (CSEMS) on the accuracy of EUS-FNA cytology in patients with solid pancreatic masses.

PATIENTS AND METHODS

We conducted a retrospective study evaluating 677 patients with solid pancreatic head/uncinate lesions and a previous biliary stent in whom EUS-FNA was performed. The patients were stratified into two groups: (1) those with a plastic stents and (2) those with CSEMS. Performance characteristics of EUS-FNA including the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were compared between the two groups.

RESULTS

The frequency of obtaining an adequate cytology by EUS-FNA was similar in both the CSEMS group and the plastic stent group (97 vs. 97.1 % respectively; p = 1.0). The sensitivity, specificity, and accuracy of EUS-FNA was not significantly different between patients with CSEMS and plastic stents (96.8, 100, 100 % and 97.3, 98, 99.8 %, respectively). The negative predictive value for EUS-FNA was lower in the CSEMS group compared to the plastic stent group (66.6 vs. 78.1 % respectively; p = 0.42). There was one false-positive cytology in the plastic stent group compared to none in the CSEMS group.

CONCLUSIONS

In a retrospective cohort trial, EUS-FNA was found to be highly accurate and safe in diagnosing patients with suspected pancreatic cancer, even in the presence of a plastic or metallic biliary stent. The presence of a stent did not contribute to a higher false-positive cytology rate.

Use of a novel adjunctive kissing-balloon technique with the Trellis device to successfully prevent embolization across juxtaposed kissing aortoiliac stents

The Trellis thrombectomy system (Covidien) has been used successfully to perform isolated pharmacomechanical thrombectomy of both venous and arterial thrombi. The device is designed to provide localized treatment while preventing both systemic spread of the thrombolytic agent and also distal embolization. However, when this device is utilized to remove thrombi at bifurcation lesions, embolization into the contralateral vessel can potentially occur. We describe a novel and simple technique of adjunctive kissing balloon inflation while using the Trellis device for the management of an aortoiliac occlusion that occurred in one of two juxtaposed stents previously placed in the distal aorta into the bilateral iliac arteries. This technique prevented distal embolization into the contralateral iliac artery.

Optimum palliation of inoperable hilar cholangiocarcinoma: comparative assessment of the efficacy of plastic and self-expanding metal stents

BACKGROUND

Endoscopic retrograde biliary drainage (ERBD) with plastic or self-expanding metal stents (SEMS) is often performed for palliative care for cholangiocarcinoma.

OBJECTIVE

The objective was to compare the clinical effectiveness, including stent patency, complication rate, and need for salvage percutaneous transhepatic biliary drainage, of SEMS and plastic stents.

METHODS

A total of 100 patients with inoperable cholangiocarcinoma were identified from an endoscopic database from 1/1/01 to 9/30/06 at a tertiary cancer hospital and their clinical history was retrospectively reviewed. All patients were followed to death, re-intervention, or for at least one year. Stent patency and patient survival were estimated by Kaplan-Meier analysis, supplemented by the log-rank test for comparisons between groups.

RESULTS

Forty-eight patients had SEMS placed and 52 patients had plastic stents placed. ERBD was successful in 46 (95.8%) in the SEMS group and 49 (94.2%) in the plastic group (P = 0.67). Median patency times were 1.86 months in the plastic group and 5.56 months in the SEMS group (P < 0.0001). A mean of 1.53 and 4.60 re-interventions were performed in the SEMS and plastic groups, respectively (P < 0.05). Complications occurred in 4/48 (8.3%) in the SEMS group and 4/52 (7.7%) in the plastic group (P = 0.79). Median survival was 9.08 and 8.22 months in the SEMS and plastic stent groups, respectively (P = 0.50).

CONCLUSION

Metallic stent patency was superior to that of plastic stents in all Bismuth-Corlette classifications of hilar cholangiocarcinoma with similar complication rates. SEMS seem to be cost-effective and, when feasible, should be considered as an initial intervention in patients with inoperable hilar cholangiocarcinoma.

Cost-effectiveness of the Taxus paclitaxel-eluting stent in the Swedish healthcare system

OBJECTIVE

To analyse the cost-effectiveness of Taxus compared to a bare-metal stent in patients with coronary artery disease in the Swedish healthcare setting.

DESIGN

A decision-analytic model combining clinical data on revascularization rates with Swedish unit costs for medical resources and utility data from the literature.

RESULTS

For patients of moderate risk, the average cost per patient at 12 months is 72,200 SEK for Taxus and 66,900 SEK for a bare-metal stent, while the average cost for high risk patients is nearly equivalent (73,000 vs. 71,700 SEK). The cost per revascularization avoided is generally favourable, while the incremental cost per QALY gained varies depending on the assumptions made; from 2,351,000 SEK for patients of moderate risk at 12-months to cost saving at 24 months for high risk patients. Budget impact scenarios at 12 months are cost-neutral.

CONCLUSION

The Taxus stent is cost-effective in high risk patients, particularly at 24 months. Although it may be less cost-effective for the general population, there is still a substantial offset of initial procedure costs through lower rate of repeat revascularizations.

Comparison of sarpogrelate and ticlopidine in bare metal coronary stent implantation

BACKGROUND

The efficacy and safety of sarpogrelate, a selective 5-hydroxytryptamine receptor subtype 2A antagonist, have not yet been established in bare metal coronary stenting. Accordingly, we sought to clarify whether treatment with sarpogrelate is clinically useful in bare metal coronary stenting.

METHODS

A total of 450 patients who underwent successfully planned or unplanned bare metal coronary stenting were randomly divided into the following 2 groups: the sarpogrelate (300 mg/day) plus aspirin (100 mg/day) group (group S, n=225) and the ticlopidine (200 mg/day) plus aspirin (100 mg/day) group (group T, n=225). Either sarpogrelate or ticlopidine was administered for at least 4 weeks after the procedure. Follow-up coronary arteriography was performed at 6 months after the procedure. The primary endpoints were the incidence of adverse drug reactions requiring a withdrawal of treatment and the rate of binary restenosis. The secondary endpoint was the incidence of stent thrombosis.

RESULTS

The incidence of adverse drug reactions requiring a withdrawal of treatment was significantly lower in group S than in group T (0.44% vs 8%, p=0.002). The rate of binary restenosis did not differ significantly between groups S and T (16.9% vs 18.2%). In addition, the incidence of subacute stent thrombosis did not differ between groups S and T (0.44% vs 0.44%).

CONCLUSIONS

The incidence of adverse drug reactions requiring a withdrawal of treatment was significantly lower with sarpogrelate use than with ticlopidine use. The rate of binary restenosis and the incidence of subacute stent thrombosis did not differ between both drug groups.

Sirolimus-eluting stents compared with standard stents in the treatment of patients with primary angioplasty

BACKGROUND

Sirolimus-eluting stents have been shown to decrease restenosis and reintervention as compared with standard stents. We evaluated the use of sirolimus-eluting stents in primary percutaneous coronary intervention for acute myocardial infarction with ST-segment elevation.

METHODS

We randomly assigned 120 patients to compare sirolimus-eluting stents with uncoated stents in primary percutaneous coronary intervention for acute myocardial infarction with ST-segment elevation. The primary end point was composite: death from cardiac causes, recurrent myocardial infarction, or target-lesion revascularization after 360 days.

RESULTS

The rate of the primary end point was 6.7% in the sirolimus-eluting stent and 11% in the bare-metal stent group (relative risk 1.75, 95% CI 0.47-6.57, P = .402). The survival free from target-vessel failure showed a higher trend in the sirolimus-eluting stent group than in the bare-metal stent group (0.0% vs 5.7%, P = .064). There was no significant difference between the 2 groups in the rate of death (5% and 3.6%, respectively; P = .736), reinfarction (1.7% and 1.8%, respectively; P = .940), or stent thrombosis (3.4% and 1.8%, respectively; P = .621).

CONCLUSIONS

Among selected patients with acute myocardial infarction and ST-segment elevation, the use of sirolimus-eluting stents shows a trend to reduce the rate of target-vessel revascularization in comparison with bare-metal stent.

[Dual platelet aggregation inhibition in coronary artery stent implantation--what is evidence-based?]

Dual platelet inhibition (ASA and clopidogrel) is the generally accepted standard therapy to avoid stent thrombosis although clopidogrel is not approved for this indication in Germany. The duration of dual platelet inhibition depends on the complexity of the stenosis, plaque activity and the type of stent implanted. Recent analyses suggested that implantation of drug eluting stents is associated with a substantially higher rate of stent thrombosis when compared with bare metal stents. This in turn fueled an ongoing debate about the optimal duration of dual platelet inhibition after implantation drug eluting stents. Guideline rcommendations vary between between 3 months and lifelong therapy with updates and additional statements published on a monthly basis leaving cardiologists and primary care providers in a state of therapeutic uncertainty. Taking the most recent guidelines and professional statements into account the following duration of dual platelet inhibition can be recommended: dual platelet inhibition for 1 month after implantation of bare metal stents, dual platelet inhibition for 9-12 months after an acute coronary syndrome; dual platelet inhibition for at least 12 months after implantation of drug eluting stents and brachytherapy in patients who are not at high risk for bleeding. Patients with previously implanted drug eluting stents who are currently taking dual antiplatelet therapy are at high risk for developing stent thrombosis when a situation arises that requires cessation or interruption of dual platelet inhibition. Therefore, the interventionalist is advised to carefully discuss risks and benefits of the selected stent and clearly document the decision process in an accepted consent form. When elective or urgent surgery is required the surgeon and practitioner must decide whether the procedure can be performed with reasonable safety without discontinuation of antiplatelet therapy posing a higher bleeding risk to the patient. Patients on chronic oral anticoaglation should be additionally treated with clopidogrel for 1 month after implantation of bare metal or 12 months after drug-eluting stents. Additional treatment with ASS is not generally recommended since the bleeding risk of this triple medication may overweigh the benefits of dual antiplatelet inhibition.

Randomized comparison of dexamethasone-eluting stents with bare metal stent implantation in patients with acute coronary syndrome: serial angiographic and sonographic analysis

AIMS

The aim of this study is to compare the anti-inflammatory effect of the dexamethasone preloaded stent (Dexamet, Abbott, Galway, Ireland) with the bare metal stent (BMS; BiodivYsio, Biocompatibles Cardiovascular LTD, Galway, Ireland) in patients with acute coronary syndrome (ACS) assessed by angiographic (QCA) and intracoronary ultrasound (ICUS).

METHODS AND RESULTS

One hundred twenty patients with ACS were randomly assigned to revascularization using the Dexamet stent (n = 60) or BMS (n = 60). Serial QCA analysis and ICUS analysis were performed during long-term follow-up (2.9 F; 20 MHz transducer; Volcano Corp, Brussels, Belgium). Power calculations were performed for QCA-derived differences of lumen loss. In addition, statistical analysis was performed (SPSS for Windows 12.0.1). The target lesion revascularization rate was lower in the Dexamet group (10 [16.67%] vs 20 [33.33%] patients; P = .031). The QCA revealed improved lumen restoration in the Dexamet stent group (lumen loss, 0.55 +/- 0.65 vs 1.07 +/- 0.92 mm [P = .001]; loss index, 0.20 +/- 0.23 vs 0.46 +/- 0.42 [P < .001]). The ICUS revealed greater neointimal proliferation in the BMS versus the Dexamet stent group (3.36 +/- 1.03 vs 3.05 +/- 1.38 mm2; P < .001). Death (n = 1) and the number of total occlusions of the stent segment (n = 1) were identical in both groups.

CONCLUSION

Dexamet stents, in comparison with the BMS stents, reduced the target lesion revascularization rate in patients with ACS and lead to better lumen restoration during long-term follow-up.

Update on bioabsorbable stents: from bench to clinical

Permanent metallic stents are associated with limitations such as continued mechanical stress, transfer to the tissue, and continued biological interaction with the surrounding tissue. They are also associated with late stent thrombosis and artifacts when non-invasive technologies such as MRI and MSCT are used. The potential advantages of bioabsorbable polymeric or metallic stents are to leave no stent behind, they are fully compatible with MRI and MSCT imaging, and are not associated with late stent thrombosis. This review covers the different stent programs as they move from bench to bed and clinical trials. Bioabsorbable stents are considered the next frontier of stenting and we will discuss their potential to fulfill this promise in interventional cardiology.

[Prospective study of the treatment of localised ureteric strictures by wire mesh stent]

AIMS

To assess efficacy of Mémotherm BARD ureteral metallic stent in the treatment of non-operable ureteral stenoses.

MATERIAL AND METHOD

Prospective evaluation of ureteral stenoses consecutively treated using Mémotherm BARD ureteral metallic stent. Assessment criteria (recurrence frequency, permeability, tolerance, complications) were measured by clinical examination, Intra Veinous Pyelography, renal sonography, urine culture at 1, and every 3 months.

RESULTS

Thirteen stents were inserted in 12 patients (mean age: 68 yrs) presenting with subsequent ureteral stenosis (9 neoplastic, 3 following radiotherapy) over a 3 year period. No technical difficulty was observed. Mean follow-up was 19 months. Stenosis recurrence was observed in 5 patients, due to tumoural progression, but with no tumour in-growth. There was non incrustation or migration, pain, hematuria, infection due to the stent. All stent remained permeable and functional in surviving patients.

CONCLUSIONS

In our experience, Mémotherm BARD ureteral metallic stent could be considered a useful cost-effective alternative to double J stent or traditional surgery in non-operable or end-of-life patients. The high ureteral stenosis recurrence rate was linked to the patient initial pathology. Considering these encouraging results, this study could represent the first stage of a multicenter tracker-study, which would permit to take into account further technological development of this type of material.

Meta-analysis of clinical trials on use of drug-eluting stents for treatment of acute myocardial infarction

BACKGROUND

Recent trials have shown the effects of drug-eluting stents (DES) in treatment of acute myocardial infarction (AMI), but data on the clinical outcome are still incomplete.

METHODS

We performed a meta-analysis of all trials comparing DES and bare-metal stents (BMS) in AMI.

RESULTS

We found 7 randomized trials comparing the effects of DES and BMS in AMI, enrolling a total of 2357 patients (1177 with DES and 1180 with BMS) with a follow-up of 8 to 12 months. Incidence of major cardiac events (death, myocardial infarction, or revascularization) was 9.3% in patients treated with DES and 17.6% in patients with BMS, with a relative risk (RR) of 0.53 with 95% CI 0.43 to 0.66. Incidence of death or myocardial infarction was similar in the two groups, occurring in 5.8% of patients with DES and 6.9% of patients treated with BMS, with an RR of 0.84 (95% CI 0.62-1.15). Target lesion revascularization occurred in 4.8% of DES and in 12.0% of BMS patients, with an RR of 0.40 (95% CI 0.30-0.54). Stent thrombosis occurred in 2.3% in DES versus 2.6% in BMS patients, with an RR of 0.87 (95% CI 0.53-1.45). There was no heterogeneity among trials in any of the analyses (I2 = 0% for all).

CONCLUSIONS

Drug-eluting stents significantly reduce need for revascularization in patients with AMI, without changes in incidence of death or myocardial infarction. Use of DES is not associated with an increased risk of stent thrombosis at 1-year follow-up.

Drug‐eluting coronary stents — a note of caution

There are two types of coronary stents: bare-metal stents (BMS) that cost about $800 each, and drug-eluting stents (DES) that cost about $3,300 each. DES reduce the rate of restenosis but have a higher incidence of late stent thrombosis, particularly if dual antiplatelet therapy with aspirin and clopidogrel is interrupted. Stent thrombosis has a myocardial infarction rate of 70% and a mortality rate of 31%-45%. Randomised studies of BMS versus DES show no increase in myocardial infarction or death with DES in simple coronary lesions, but in clinical practice, DES are mainly used in complex coronary disease where the rate of stent thrombosis is higher. Registry data suggest an increased rate of death and myocardial infarction of 0.5%-1.0% per annum with DES. Clinicians need to be aware of the risks associated with prematurely ceasing dual antiplatelet therapy in patients with DES.

[Acute myocardial infarction after discontinuing aspirin two years after implantation of a drug-eluting coronary stent]

HISTORY AND ADMISSION FINDINGS

A 48-year-old man was admitted to our cardiac catheterization unit with severe chest pain 75 minutes after onset of symptoms. Two years before he had undergone percutaneous coronary intervention (PCI) for stable angina pectoris with implantation of a drug-eluting stent (TAXUS) into the proximal left anterior descending artery. Antiplatelet therapy with 75 mg clopidogrel was given for one year, together with 100 mg aspirin. Subsequently he was put on low-dose aspirin monotherapy. Eight days before admission aspirin was discontinued because a tooth extraction was planned.

DIAGNOSTIC PROCEDURES

The ECG showed significant ST-segment elevation in the precordial leads V1-5.

TREATMENT AND OUTCOME

90 minutes after onset of symptoms coronary angiography was performed and an in-stent thrombosis of the proximal left coronary artery was diagnosed. A successful PCI was performed and abiximab given. The creatine kinase concentration increased to a maximum of 3170 U/l. The pre-discharge echocardiogram showed a slightly reduced left ventricular ejection fraction. After the procedure the patient was stable and free of chest pain and he was discharged from the hospital after one week.

CONCLUSION

Discontinuing antiplatelet therapy, even years after implantation of a drug-eluting coronary stent, increases the risk of a late stent thrombosis. This should be taken into account especially before any procedure, even with a low bleeding risk such as tooth extractions. Antiplatelet treatment should be continued, even if there is a risk increasing minor bleeding complications, so that any life-threatening complication of an acute myocardial infarction is avoided.

Engineering aspects of stents design and their translation into clinical practice

The implantation of coronary stents is a relevant part of interventional procedures for percutaneous revascularization. The wide acceptance of coronary stenting was based on the results of two highly significant trials which have shown the superiority of stenting over balloon angioplasty in terms of reduction of angiographic restenosis and need for repeated intervention in focal lesions and large coronary arteries. Since then, the growing use of stent market was impressive. A rapidly increasing number of different stent type with different material and designs has been introduced in the market both for bare metal stent and drug eluting stent. This review will summarize the different components of stent design that are important in term of biological response of the arterial wall and clinical outcome. In addition, new stent platforms, mainly represented by the biodegradable stent will be shortly reviewed since it may provide in the near future a more "physiological" answer to stent implantation, reducing vascular injury and accelerating vessel healing with consequent improving in clinical outcome.

One-Year Mean Follow-up of 41 Patients Treated With Bifurcation Stenting

Forty-one patients, mean age 61 +/- 13 years, had stenting of bifurcation coronary artery lesions. Of the 41 patients, a crushing stent was used in 33 patients (80%), a T stent in 6 patients (15%), a kissing stent in 1 patient (2%), and side branch angioplasty in 1 patient (2%). Mean follow-up was 12 months (range 7-17 months). At follow-up, of the 41 patients, none (0%) died, 1 (2%) had a myocardial infarction, 3 (7%) had thrombotic stent occlusion, 3 (7%) had restenosis, 4 (10%) had target lesion revascularization, and 6 (15%) had myocardial infarction or target lesion revascularization or had died.