Percutaneous intervention of a giant native coronary artery aneurysm using self-expanding stents.

In the absence of standardized management guidelines, coronary artery aneurysms (CAAs) present therapeutic challenges. Percutaneous coronary intervention (PCI) is rarely explored, especially in giant aneurysms with persistent angina, where surgery might be presumed as a preferred option. We describe the technical aspects and feasibility of PCI using Gore Viabahn expanded polytetrafluoroethylene (ePTFE)-covered nitinol self-expanding stents in a 66-year-old woman with a complex medical history and an enlarging, symptomatic right coronary artery aneurysm. The case was complicated by endoleak after the first stent, but intravascular ultrasound guidance enabled the precise deployment of additional stents, resulting in the successful exclusion of the aneurysm. This case demonstrates steps to successful CAA PCI with Gore Viabahn ePTFE-covered nitinol self-expanding stents and emphasizes that in unsuitable surgical candidates, PCI might be a potential alternative for symptomatic CAAs.

Multicenter Registry of Common Femoral Artery Disease Treated With Endovascular Revascularization Using Interwoven Nitinol Stents: An Observational Retrospective Study.

PURPOSE: Surgical thromboendarterectomy has been the gold standard treatment for common femoral artery (CFA) disease. However, endovascular therapy (EVT) is conducted in certain patients with CFA lesions because of multiple comorbidities. The interwoven nitinol stent (IWS) has been developed to prevent stent fracture. Thus, this study aimed to evaluate the feasibility of EVT using IWS for CFA lesions in clinical practice. MATERIALS AND METHODS: This retrospective multicenter registry analyzed patients who had symptomatic lower-extremity artery disease due to CFA lesions and underwent EVT using IWS between 2019 and 2021. The primary endpoint was restenosis 2 years after EVT. RESULTS: This study enrolled a total of 177 patients with 196 CFA lesions. The 2-year estimate of freedom from restenosis was 88.0%. The 2-year freedom rates from the target-lesion revascularization, major amputation, and all-cause death were 92.9%, 99.0%, and 75.2%, respectively. The clinical features significantly associated with restenosis risk were the reference vessel diameter (RVD, per 1.0 mm, hazard ratio [HR], 0.24 [0.08-0.70]; p=0.009), external iliac artery (EIA) involvement (HR=4.03 [1.56-10.4]; p=0.004), superficial femoral artery (SFA) involvement (HR=3.05 [1.00-9.25]; p=0.049), body mass index (BMI; per 1.0, HR=0.85 [0.73-0.99]; p=0.032), occlusion of deep femoral arteries (DFAs) at baseline (HR=7.89 [2.04-30.5]; p=0.003), and chronic limb-threatening ischemia (CLTI, HR=2.63 [1.02-6.78]; p=0.045). Their significant association was also confirmed by the random survival forest analysis. During a median follow-up of 12.0 months, guiding sheaths were inserted via CFAs implanted IWSs in 73 cases (37.2%), and no patients had cannulation-related complications, such as failed hemostasis, fracture of IWS, and stent occlusion. CONCLUSIONS: Endovascular therapy using IWS in CFA lesions showed acceptable 2-year patency rates at 88.0% and might preserve the arterial access via the ipsilateral CFAs. Small RVD, involving EIA and SFA lesions, emaciation, occluded DFA, and CLTI are associated with poor 2-year patency rates following EVT, thus, IWS implantation in CFA lesions may be an option for patients unsuitable for surgical revascularization. CLINICAL IMPACT: This retrospective multicenter registry enrolled 177 patients with 199 CFA lesions treated with EVT using interwoven nitinol stents, because surgical thromboendarterectomy was difficult due to their multiple comorbidities. The 2-year estimate of freedom from restenosis was acceptable at 88.0%. The 2-year freedom rate from major amputation was also high at 99.0%. Moreover, during a median follow-up of 12.0 months, guiding sheaths were inserted via CFAs implanted IWSs in 73 cases, and no patients had cannulation-related complications such as failed hemostasis, fracture of IWS, and stent occlusion.

Results of Palliative Stenting in Malignant Superior Vena Cava Syndrome Analyzing Self-Expanding Stainless Steel and Nitinol Venous Bare Metal Stents.

PURPOSE: The purpose was to analyze the technical, clinical, and survival outcomes of our patients with malignant superior cava vein syndrome (SVCS) treated with endovascular approach and analyze the efficacy of different stent types used. MATERIAL AND METHODS: It is an observational, retrospective, single-center study. From 2006 to 2023, 42 patients (32 male, 10 female, mean age 62 years, age range, 41-87 years) underwent percutaneous stent placement for malignant SVCS. One stainless steel stent (Wallstent) and 2 venous nitinol stent type (Sinus-XL, Venovo) were used. Follow-up mean was 276 days. RESULTS: A total of 53 stents were deployed. Clinical success was 97.6% in less 24 hours. Technical success was achieved in 97.6%. No complications were found except 1 patient died during the procedure due to stent migration and atrial dissociation (2.3%). Overall intraprocedural stent migration rate was 11.9% (18.8% stainless steel stent, 9.6% nitinol stent, p>0.05). Overall survival rates were 87.8%, 41.99%, and 34.12%, and overall primary patency rates were 100%, 93.3%, 91.6% at 1, 6, and 12 months, respectively. CONCLUSIONS: Endovascular treatment is a safe and effective therapeutic option for SVCS with high technical and clinical success rates and low complication and recurrence rates. CLINICAL IMPACT: The malignant superior cava vein syndrome is a rare clinical entity treated classically with radiation and chemotherapy with a slower response, or surgical bypass, which is an aggressive surgical technique. Endovascular treatment offers a low-invasive technique with quick clinical resolution and good permeability results. However, further studies are lacking to deal with procedure technical characteristics, stent type used, technical complications, and medium- and long-term patency studies. This study aims to evaluate all these items, analysing self-expanding stainless steel and nitinol venous bare metal stents, and add value to endovascular treatment, confirming the good results of this technique.

Endovascular treatment with interwoven nitinol stent for common femoral artery lesions: 2-year outcomes of a single center experience.

OBJECTIVE: The study aimed was to report 2-year outcomes of endovascular treatment with interwoven nitinol (Supera™) stent for common femoral artery (CFA) lesions. METHODS: We reviewed the clinical data of 20 patients who presented with CFA stenosis or occlusion and underwent balloon angioplasty followed by Supera™ stenting in CFA between February 2016 and January 2022. The outcomes were evaluated in these patients in terms of technical success, post-intervention complications, reintervention, and cumulative patency (1 year, and 2 years). RESULTS: The study included 20 patients (22 lesions) who presented with isolated CFA lesions (3), iliac lesions involving CFA (6), superficial femoral artery (SFA) lesions involving CFA (8), and extensive lesions from the iliac artery to SFA (5). There were 16 men (80%) with a mean age of 69.7 years (range, 34-83). Hypertension, smoking, and diabetes were found in 15 (75%), 7 (35%), and 7 patients (35%), respectively. Clinical presentations were Rutherford stage 5 (9, 45%), Rutherford stage 4 (5, 25%), Rutherford stage 6 (4, 20%), and Rutherford stage 3 (2, 10%). Technical success was achieved in all patients (100%). The procedures for treatment were isolated CFA Supera™ stenting (1, 4.5%), CFA plus DFA Supera™ stenting (jailed SFA) (2, 9.1%), CFA plus SFA Supera™ stenting (jailed DFA) (8, 36.4%), CFA Supera™ stenting plus bare iliac stenting (Astron) (6, 27.3%), CFA plus SFA Supera™ stenting (jailed DFA) plus bare iliac stenting (Astron) (5, 22.7%), and additional DFA angioplasty (7, 31.8%). The rate of in-hospital mortality and morbidity were 0% and 10%, respectively. Distal embolization after pre-dilatation occurred in 1 patient, and cerebral infarction occurred 12 h after the procedure in 1 patient. The mean follow-up time was 23 months (range, 2-64). During the follow-up period, in-stent occlusion occurred in 2 patients at 9 and 46 months. Re-intervention was performed in 1 patient due to recurrent symptom of claudication. The cumulative primary patency at 1 year and 2 years were 93.3% and 93.3%, respectively. CONCLUSION: Endovascular treatment with interwoven nitinol (Supera™) stent for CFA lesions was associated with acceptable outcomes at 2 years.

Biomechanical comparison of bone staple fixation methods with suture material for median sternotomy closure using 3D-printed bone models.

AIM: To compare the biomechanical properties of three different sternal closure techniques in a 3D-printed bone model of a sternum from a 30-kg dog. METHODS: Median sternotomy was performed on a total of 90 three-dimensional (3D) copies of a polycarbonate (PC) model of a sternum, generated from the CT images of the sternum of a 30-kg German Shepherd dog. Three different methods were used to repair the sternotomies: polydioxanone suture (group PDS, n = 30), stainless steel bone staples (group SS, n = 30), and nitinol bone staples (group NS, n = 30). Each repair method was tested by applying tensile force in one of three ways (longitudinally, laterally, or torsionally) resulting in a sample size of n = 10 for each repair method-loading combination. In all experiments, the loads at 1-mm and 2-mm gap formation, failure, and the displacement at the failure point were measured. RESULTS: In lateral distraction and longitudinal shear tests, NS and SS staple repairs required application of significantly greater force than PDS across all displacement criteria (1 and 2 mm). NS exhibited significantly greater failure load than PDS. In torsion tests, NS required significantly greater application of force compared to SS or PDS at all displacement criteria (1 and 2 mm) and exhibited a greater failure load than PDS. In terms of displacement at failure point, PDS suture showed more displacement than SS or NS across all experiments (laterally, longitudinally, torsionally). CONCLUSIONS: In this study, bone staples were mechanically superior to PDS suture in median sternotomy closure using 3D-printed bone model in terms of 1-mm, 2-mm displacement loads, and displacement at failure. NS had a higher failure load than PDS under lateral, longitudinal, and torsional distraction. CLINICAL RELEVANCE: These study results imply that bone staples can be considered as an alternative surgical method for median sternotomy closure in dogs.

Double-wire woven nitinol stent for treating dogs with refractory tracheal collapse: A case series.

This retrospective case series describes the signalments, clinical signs, diagnostic test results, and postoperative complications obtained from the medical records of 10 client-owned dogs that underwent treatment for grade IV tracheal collapse using double-wire woven nitinol stents between October 2017 and September 2021. Respiratory signs resolved in all dogs immediately after tracheal stent placement. Mild to moderate stent fractures were identified in five dogs, of which two showed concurrent respiratory distress necessitating re-stenting after several months. Minor complications, such as stent migration, were absent. The double-wire woven nitinol stent optimised for the canine trachea showed favourable outcomes and minimal complications.

Cannulated screws versus nitinol staple for tarsometatarsal fusion: A cadaveric biomechanical comparison model.

BACKGROUND: The objective of this study was to evaluate the biomechanical stability of a medially placed nitinol staple compared to two crossed-screws in the first TMT-1 joint fusion in a cadaveric cyclic loading model. METHODS: Seven matched pairs (N = 7) of lower limb cadaveric specimens were utilized. TMT-1 joints from each donor were fixed with a medially placed nitinol staple or dorsally placed two 3.5 mm partially threaded cannulated crossed-screws. Specimens were tested in a 4-point bending setting with increasing cyclic forces. RESULTS: The mean plantar gapping was not significantly different between the two groups at any loading stage below 200 N. Specimens fixed with a nitinol staple failed at a mean load of 305 ± 57 N. Conversely, those fixed with crossed-screws failed at 373 ± 86 N. (P = .09). CONCLUSION: There was no statistical difference between a medially placed nitinol staple and dorsally placed crossed-screws in failure loads and plantar gapping under cyclic loads at the TMT-1 joint, however, the staple fixation was much more variable. LEVEL OF EVIDENCE: Level V, basic science study, biomechanics.

Treatment of Long Femoropopliteal Lesions With Self-Expanding Interwoven Nitinol Stent: 24 Month Outcomes of the STELLA-SUPERA Trial.

PURPOSE: The performance of self-expanding interwoven nitinol stent (Supera) in femoropopliteal interventions has been proven through trials with short lesions and with relatively low proportion of occlusions. There is limited evidence of Supera stent in long lesions. The aim of this study was to assess the clinical safety and efficiency of the Supera stent in the treatment of long femoropopliteal lesions (Trans-Atlantic Inter-Society Consensus [TASC] C/D) in patients with symptomatic peripheral arterial disease (PAD). METHODS: The STELLA SUPERA (STEnting Long de L'Artère fémorale superficielle par le stent métallique Supera) is a prospective, 2-center, single-arm study. Patients with symptomatic (Rutherford stages 2-6) de novo and TASC C/D lesions of the femoropopliteal segment were treated with Supera stent. The primary endpoint was the primary sustained clinical improvement at 12 months. Follow-up included clinical examination, duplex scan, and biplane X-ray up to 24 months. RESULTS: Between December 2016 and October 2018, 48 symptomatic patients with 49 femoropopliteal lesions (TASC D = 32, 65%) were treated. The mean lesion length was 234 ± 123 mm, and 78% were total occlusion. The mean stented lesion length was 273 ± 127 mm. At 12 and 24 months, the primary sustained clinical improvement rate was 87.2% and 79.7%, respectively. The Rutherford category assessment was significantly improved at 24 months compared with baseline (p=0.02). At 24 months, the primary patency and freedom from target lesion revascularization (TLR) rates were 77.9% and 86.9%, respectively. The ankle-brachial pressure index increased from 0.62 ± 0.15 at baseline to 0.93 ± 0.15 at 24 months (p<0.0001). There were no stent fractures at 24 months. CONCLUSION: The use of Supera stent in long lesions (TASC C/D) is a safe and effective endovascular alternative. These results reinforce the need for randomized clinical trials to assess the value of interwoven stents for long femoropopliteal lesions.

Treatment of Long Femoropopliteal Occlusive Lesions With Self-expanding Interwoven Nitinol Stent: 24 Month Outcomes of the STELLA-SUPERA-SIBERIA Register Trial.

PURPOSE: The efficacy and safety of the Supera stent in superficial femoral artery (SFA) have been reported mostly in shorter lesions with relatively low proportion of occlusions. There are little data on the effectiveness of the Supera stent in long lesions. The aim of this study was to assess the clinical safety and efficiency of the Supera stent in the treatment of long femoropopliteal occlusive lesions (Trans-Atlantic Inter-Society Consensus [TASC] C/D) in patients with symptomatic peripheral artery disease. MATERIALS AND METHODS: The STELLA-SUPERA-SIBERIA is a prospective, single-center, single-arm study. Patients with symptomatic (Rutherford stages 3-6) de novo and TASC C/D occlusive lesions of the femoropopliteal segment were treated with Supera stent. The primary endpoint was the 12 month rate of primary sustained clinical improvement (upward shift on the Rutherford classification to a one level without the need for repeated target lesion revascularization (TLR) in surviving patients without the need for unplanned amputation). Secondary endpoints were the 24 month of primary sustained clinical improvement, MALE, limb salvage, the primary patency, the secondary patency, 24 month MACE. Follow-up included clinical examination, duplex scan, and biplane x-ray up to 24 months. RESULTS: Between April 2019 and January 2020, 52 symptomatic patients with 55 long femoropopliteal occlusive lesions (52.7% TASC D lesions and 47.3% TASC C lesions) were treated. The mean target lesion length was 205±72 mm. All patients had total occlusions. The mean lesion length of the implanted Supera stents was 198±82 mm. At 12 and 24 months, the primary sustained clinical improvement rate was 80.2% and 63.6%, respectively. The Rutherford category assessment was significantly improved at 24 months compared with baseline (p=0.02). The primary patency rate at 12 and 24 months was 78.1% and 60.0%, respectively. At 12 and 24 months, freedom from TLR was 83.5% and 81.8%, respectively. There were no stent fractures at 24 months. CONCLUSION: Supera Stent implantation for TASC C/D femoropopliteal lesions revascularization appears to be a safe and efficient implant given the complexity of the treated lesions. Head-to-head studies are mandatory to establish Supera Stent as an alternative tool to open surgery for long femoropopliteal lesions. CLINICAL IMPACT: Our study indicated, that using self-expanding interwoven nitinol stent for TASC C/D femoropopliteal lesions revascularization appears to be a safe and efficient implant given the complexity of the treated lesions. Although bypass grafting is recommended for prolonged femoropopliteal lesions, open surgery is more traumatic and is associated with greater risks than endovascular procedures. Our findings suggest that the use of interwoven nitinol stents can overcome the disadvantages of traditional stents in such cases, which may help to improve patients' outcomes and reduce the risk of adverse events.

Novel Self-Expanding Interwoven Nitinol Stent for Treating Femoropopliteal Artery Disease: 12-Month Results of Single-Center First-in-Man Study.

PURPOSE: To evaluate the safety and efficacy of Innospring® stent, a novel self-expanding interwoven nitinol stent, in treating femoropopliteal atherosclerotic lesions. METHODS: A prospective, single-center, single-arm, first-in-human study enrolled 15 patients (mean age 73.1 years; 13 men) to evaluate the safety and efficacy of the Innospring® stent monitored by core laboratories. The inclusion criteria were claudication or ischemic rest pain, de novo lesions or nonstented restenosis, >70% stenosis, lesion length <20 cm, and a reference vessel diameter of 4-7 mm. The primary safety endpoint was 30-day major adverse events. The primary efficacy end point was stent patency at 12 months. Follow-up evaluations were conducted at 30 days, 6 months, and 12 months. RESULTS: The lesion length was 6.1 ± 3.5 mm. Fourteen (93.3%) patients had lesions of the superficial femoral artery and 3 (20.0%) patients had lesions of the popliteal artery. Nine (60.0%) patients had moderate-to-severe calcified lesion. Technical and procedural success was 100%. No patients experienced major adverse events in the first 30 days. The Rutherford category showed significant and sustained improvement at 6 and 12 months. The 12-month follow-up radiographs obtained in 13 patients confirmed the absence of stent fractures in 100% of examinations. The cumulative primary stent patency rate at 6 and 12 months were 93.3% and 84.6%, respectively. CONCLUSION: Stenting of the superficial femoral and popliteal arteries using the Innospring® stent is safe and effective. This competing interwoven nitinol stent may provide superior stent integrity and fracture-resistance as well as serve areas under extreme mechanical stress. CLINICAL IMPACT: Endovascular recanalization is a widely accepted and recommended treatment for symptomatic peripheral artery diseases. The Innospring® stent is a novel self-expanding interwoven stent containing eight nitinol wires with additional radial force, fracture-resistance, and visibility under fluoroscopy. This first-in-human study using the Innospring® stent in patients with femoropopliteal occlusive disease reported that stenting of the superficial femoral and popliteal arteries using the Innospring® stent is safe and effective. This competing interwoven nitinol stent may provide an impressive stent integrity and fracture-resistance as well as serve areas under extreme mechanical stress.

Multicenter, retrospective registry of isolated atherosclerotic popliteal arteries treated with endovascular revascularization.

Isolated atherosclerotic popliteal lesions (IAPLs) have been considered challenging. This study aimed to investigate the efficacy of endovascular therapy (EVT) using the newer devices for IAPLs. This retrospective multicenter registry analyzed patients with lower extremity artery disease having IAPLs who underwent EVT using the newer devices between 2018 and 2021. The primary outcome was primary patency 1 year after EVT. A total of 392 consecutive patients undergoing EVT for IAPLs were enrolled. The Kaplan-Meier analysis showed that the primary patency and the freedom from target lesion revascularization were 80.9% and 87.8% 1 year after EVT, respectively. The multivariate Cox proportional hazards regression analysis showed that the clinical features that were independently associated with restenosis risk were drug-coated balloon (DCB) use for younger age (< 75 years old; adjusted hazard ratio, 3.08 [95% confidence interval 1.08-8.74]; P = 0.035), non-ambulatory status (2.74 [95% confidence interval 1.56-4.81]; P < 0.001), cilostazol use (0.51 [95% confidence interval 0.29-0.88]; P = 0.015), severe calcification (1.86 [95% confidence interval 1.18-2.94]; P = 0.007), and small external elastic membrane (EEM) area measured by intravascular ultrasound (IVUS) (< 30 mm2) (2.07 [95% confidence interval 1.19-3.60]; P = 0.010). From the univariate analysis, among patients treated with DCB, younger patients (n = 141) were associated with more comorbidities including smoking (P < 0.001), diabetes mellitus (P < 0.001), end-stage renal disease (P < 0.001), history of revascularization (P = 0.046) and small EEM area (P = 0.036), compared to older patients (n = 140). Moreover, smaller post-procedural minimum lumen area measured by IVUS after DCB dilatation was observed in younger patients (12 ± 4 vs. 14 ± 4 mm2, P = 0.033). This retrospective study demonstrated that the current EVT provided an acceptable 1-year primary patency rate in patients with IAPLs. The primary patency was lower following DCB in younger patients, likely due to the higher rates of comorbidities in this patient population.

Effect of Arthrodesis Device Type and Trajectory on Subtalar Joint Compression.

The use of subtalar arthrodesis procedures has been widely implemented to relieve hindfoot issues after failure of conservative treatments; however, fusion failures persist in some patients with certain risk factors. Currently, surgeons utilize cannulated screws in these arthrodesis procedures to immobilize the subtalar joint. Recent clinical studies have demonstrated improved fusion outcomes in at-risk patients using sustained dynamic compression devices in the tibiotalocalcaneal complex. These devices utilize pseudoelastic nitinol which enables sustained dynamic compression when faced with postoperative bone resorption, joint settling, and bone relaxation. While the clinical success of these devices has been established in the tibiotalocalcaneal complex, the ability of sustained dynamic compression devices to apply joint compression in the subtalar joint has not been quantified. As such, the goals of this study were to (1) compare the ability of static compression devices and sustained dynamic compression devices to apply joint compression and (2) assess the impact of device trajectory on joint compression. A custom mechanical testing fixture was utilized to test the compression applied across the subtalar joint by one sustained dynamic compression device (in anterior and posterior trajectories) as compared to 2 cannulated screws (in both parallel and diverging trajectories). Testing revealed the sustained dynamic compression devices generated 53% greater compression as compared to the static compression devices, despite single versus dual device usage, respectively. Additionally, both types of devices applied joint compression forces in an insertion trajectory-independent manner. These data illustrate the ability of a single SDC device to maintain significantly improved joint compressive forces as compared to 2 static cannulated screws, regardless of insertion trajectory. These SDC devices may be of particular interest for at-risk patients or in revision cases.

Radiographic Evaluation of Isolated Continuous Compression Staples for Akin Osteotomy Fixation.

Continuous compression implants (nitinol staples) are gaining popularity secondary to their lower profile, less demanding technique, and less surgical dissection. Biomechanical support exists; however, clinical data is limited in the foot/ankle. This study's purpose is to determine the efficacy of nitinol staples to achieve stable, bony healing in Akin osteotomies and examine their clinical outcomes, complications, re-operations, and pain scores. We performed a retrospective chart review on 90 patients (93 osteotomies) who underwent an Akin osteotomy using a nitinol staple over a 2-year period. Radiographs were randomized and independently reviewed by 3 blinded foot and ankle surgeons. Osteotomies were deemed healed if greater than 50% of the osteotomy contained bridging bone, partially healed as less than 50% bridging bone, and nonunion as no healing, broken hardware, or loss of reduction. Visual analog scale pain scores were analyzed. Radiographic union was seen in 98.9% of Akin osteotomies (92/93), with no loss of reduction or broken staples (0/95). Only 3.2% (3/93) of patients returned to the operating room unplanned: 1 infection (1.1%), 1 symptomatic hardware removal (1.1%), and 1 traumatic disruption of fixation (1.1%). Postoperative pain scores were significantly lower than preoperative. Staples are lower profile and technically less demanding compared to headed screws, plates, and tension band constructs. They offer continuous compression of the osteotomy and are rigid enough to maintain reduction. Based on the findings of this paper, the use of staples provides robust and stable fixation for Akin osteotomies and has low complication and high healing rates.

Effect of Simulated Bone Resorption on the Biomechanical Performance of Intramedullary Devices for Foot and Ankle Arthrodesis.

Midfoot and subtalar arthrodesis surgeries are performed to correct foot deformities and relieve arthritic pain. These procedures often employ intramedullary (IM) devices. The aim of the present study was to evaluate the biomechanical performance of a sustained dynamic compression (SDC) IM device compared to mechanically static devices in withstanding the effects of simulated bone resorption. Mechanically static and SDC IM devices were implanted in simulated bone blocks (n = 5/device). Compressive loads were measured with a custom-made mechanism to simulate bone resorption. The construct bending stiffness was determined from a 4-point bend test. Resorption was simulated by cutting a 1 mm or 2 mm gap in the midpoint of each construct and repeating the loading (n = 6/device). Initial compressive loads after device insertion were greater in the SDC IM devices when compared to the static devices (p < .01). The SDC device was able to sustain compression from 2 mm to 5.5 mm of simulated resorption depending upon device length, while the static devices lost compression within 1 mm of simulated resorption regardless of implant length (p < .001). In the 4-point bend test, the SDC device maintained its bending stiffness during simulated resorption whereas the static device displayed a significant loss in bending stiffness after 1 mm of simulated resorption (p < .001). The SDC device exhibited a significantly higher bending stiffness than the static device (p < .001). The SDC IM device demonstrated superior biomechanical performance during simulated resorption compared to static devices (p < .001). In conclusion, the ability of SDC IM devices to maintain construct stability and sustain compression across the fusion site while adapting to bone resorption may lead to greater fusion rates and overall quicker times to fusion than static IM devices. Surgeons who perform midfoot and subtalar arthrodesis procedures should be aware of a device's ability to sustain compression, especially in cases where bone resorption and joint settling are prevalent postoperatively.

First Tarsometatarsal Joint Fusion in Foot-A Biomechanical Human Anatomical Specimen Analysis with Use of Low-Profile Nitinol Staples Acting as Continuous Compression Implants.

Background and Objectives: The aim of this study was to investigate under dynamic loading the potential biomechanical benefit of simulated first tarsometatarsal (TMT-1) fusion with low-profile superelastic nitinol staples used as continuous compression implants (CCIs) in two different configurations in comparison to crossed screws and locked plating in a human anatomical model. Materials and Methods: Thirty-two paired human anatomical lower legs were randomized to four groups for TMT-1 treatment via: (1) crossed-screws fixation with two 4.0 mm fully threaded lag screws; (2) plate-and-screw fixation with a 4.0 mm standard fully threaded cortex screw, inserted axially in lag fashion, and a 6-hole TMT-1 Variable-Angle (VA) Fusion Plate 2.4/2.7; (3) CCI fixation with two two-leg staples placed orthogonally to each other; (4) CCI fixation with one two-leg staple and one four-leg staple placed orthogonally to each other. Each specimen was biomechanically tested simulating forefoot weightbearing on the toes and metatarsals. The testing was performed at 35-37 °C under progressively increasing cyclic axial loading until construct failure, accompanied by motion tracking capturing movements in the joints. Results: Combined adduction and dorsiflexion movement of the TMT-1 joint in unloaded foot condition was associated with no significant differences among all pairs of groups (p ≥ 0.128). In contrast, the amplitude of this movement between unloaded and loaded foot conditions within each cycle was significantly bigger for the two CCI fixation techniques compared to both crossed-screws and plate-and-screw techniques (p ≤ 0.041). No significant differences were detected between the two CCI fixation techniques, as well as between the crossed-screws and plate-and-screw techniques (p ≥ 0.493) for this parameter of interest. Furthermore, displacements at the dorsal and plantar aspects of the TMT-1 joint in unloaded foot condition, together with their amplitudes, did not differ significantly among all pairs of groups (p ≥ 0.224). Conclusions: The low-profile superelastic nitinol staples demonstrate comparable biomechanical performance to established crossed-screws and plate-and-screw techniques applied for fusion of the first tarsometatarsal joint.

Six novel minimally invasive therapies for benign prostatic hyperplasia. / æ²»ç–—è‰¯æ€§å‰åˆ—è ºå¢žç”Ÿçš„å ­ç§æ–°å¾®åˆ›æ‰‹æœ¯.

Benign prostatic hyperplasia (BPH) is the most common cause of lower urinary tract symptoms in men. When drug treatment is ineffective or conventional surgery is not suitable, novel minimally invasive therapies can be considered. These include prostatic urethral lift, prostatic artery embolisation, water vapor thermal therapy, Aquablation-image guided robotic waterjet ablation, temporary implantable nitinol device and prostatic stents. These novel therapies can be performed in outpatient setting under local anesthesia, with shorter operative and recovery times, and better protection of ejaculatory function and erectile function. General conditions of the patient and advantages and disadvantages of the each of these therapies should be fully considered to make individualized plans.

Layered Double Hydroxide-Based Micro "Chemical Factory" with Arsenic Processing and Screening Functions on Nitinol for Gallbladder Cancer Treatment.

Gallbladder cancer is a common malignant tumor of the biliary system with a high fatality rate. Nitinol (Ni-Ti) stents, a standard treatment for prolonging patients' lives, are susceptible to reocclusion and cannot inhibit tumor recurrence because they lack antitumor and antibacterial activity. Herein, an arsenic-loaded layered double-hydroxide film is constructed on Ni-Ti, forming a micro "chemical factory." The LDH plays the role of a "processer" which absorbs highly toxic trivalent arsenic (As(III)) and processes it into lowly toxic pentavalent arsenic (As(V)). It also acts as a "quality-inspector," confining As(III) in the interlayer and releasing only As(V) (the finished product) to the outside. This control mechanism minimizes the toxicity during contact with normal tissue. The acidic microenvironment and overexpression of glutathione in tumor tissues not only accelerates the release of arsenic from the platform but also triggers the in situ transformation of arsenic from lowly toxic As(V) to highly toxic As(III), exerting a strong arsenic-mediated antineoplastic effect. Such a microenvironment-responsive "chemical factory" with arsenic processing and screening functions is expected to prevent tumor overgrowth, metastasis, and bacterial infection and provide new insights into the design of Ni-Ti drug-eluting stents for gallbladder cancer treatment.

Minimally invasive treatments for benign prostatic hyperplasia: a Cochrane network meta-analysis.

OBJECTIVE: To assess the comparative effectiveness and ranking of minimally invasive treatments (MITs) for lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: We searched multiple databases up to 24 February 2021. We included randomized controlled trials assessing the following treatments: convective radiofrequency water vapour thermal therapy (WVTT; or Rezum); prostatic arterial embolization (PAE); prostatic urethral lift (PUL; or Urolift); temporary implantable nitinol device (TIND); and transurethral microwave thermotherapy (TUMT) compared to transurethral resection of the prostate (TURP) or sham surgery. We performed a frequentist network meta-analysis. RESULTS: We included 27 trials involving 3017 men. The overall certainty of the evidence of most outcomes according to GRADE was low to very low. Compared to TURP, we found that PUL and PAE may result in little to no difference in urological symptoms, while WVTT, TUMT and TIND may result in worse urological symptoms. MITs may result in little to no difference in quality of life, compared to TURP. MITs may result in a large reduction in major adverse events compared to TURP. We were uncertain about the effects of PAE and PUL on retreatment compared to TURP, however, TUMT may result in higher retreatment rates. We were very uncertain of the effects of MITs on erectile function and ejaculatory function. Among MITs, PUL and PAE had the highest likelihood of being the most efficacious for urinary symptoms and quality of life, TUMT for major adverse events, WVTT and TIND for erectile function and PUL for ejaculatory function. Excluding WVTT and TIND, for which there were only studies with short-term (3-month) follow-up, PUL had the highest likelihood of being the most efficacious for retreatment. CONCLUSIONS: Minimally invasive treatments may result in similar or worse effects concerning urinary symptoms and quality of life compared to TURP at short-term follow-up.

Exploiting the Transformation Temperature to Reform an Infolded Nitinol Self-Expanding Peripheral Stent.

PURPOSE: Nickel-titanium (nitinol) alloys possess a special set of properties that allow for a wide range of applications. Specifically, the transformation temperature for self-expanding nitinol peripheral stents allows for easy crimping at or below room temperature and reformation at body temperature becoming superelastic. CASE REPORT: We report the case of an elderly man with iliac stenting 1 month prior, who presented several weeks after recovering from coronavirus disease 2019 with recurrent anterior-wall ST-elevation myocardial infarction. This was complicated by deformation and infolding of the previously implanted nitinol self-expanding stent in his right common iliac artery (CIA). Understanding nitinol's specific properties, we proceeded with rapid injections of iced saline to cool the nitinol stent to its transformation temperature while nudging the distal end of the stent with a partially inflated balloon. This maneuver softened the nitinol stent, allowing us to "unfold" and reappose it against the wall of the right CIA, resulting in successful restoration of the original shape of the nitinol self-expanding stent. CONCLUSION: This represents the first reported case describing treatment of an infolded nitinol self-expanding peripheral stent by exploiting the transformation temperature of nitinol using iced cold saline to successfully restore the stent's original shape and structure.

A Systematic Review and Meta-Analysis of 12-Month Patency After Intervention for Iliofemoral Obstruction Using Dedicated or Non-Dedicated Venous Stents.

BACKGROUND: Endovascular stenting of the deep venous system has been proposed as a method to treat patients with symptomatic iliofemoral outflow obstruction. The purpose of this systematic review and meta-analysis was to compare the effectiveness of this treatment at 1-year following the development of dedicated venous stents. METHOD AND RESULTS: We searched MEDLINE and EMBASE for studies evaluating the effectiveness of venous stent placement. Data were extracted by disease pathogenesis: non-thrombotic iliac vein lesions (NIVL), acute thrombotic (DVT), or post-thrombotic syndrome (PTS). Main outcomes included technical success, stent patency at 1 year and symptom relief. A total of 49 studies reporting outcomes in 5154 patients (NIVL, 1431; DVT, 950; PTS, 2773) were included in the meta-analysis. Technical success rates were comparable among groups (97%-100%). There were no periprocedural deaths. Minor bleeding was reported in up to 5% of patients and major bleeding in 0.5% upon intervention. Transient back pain was noted in 55% of PTS patients following intervention. There was significant heterogeneity between studies reporting outcomes in PTS patients. Primary and cumulative patency at 1 year was: NIVL-96% and 100%; DVT-91% and 97%; PTS (stents above the ligament)-77% and 94%, and; PTS (stents across the ligament)-78% and 94%. There were insufficient data to compare patency outcomes of dedicated and nondedicated venous stents in patients with acute DVT. In NIVL and PTS patients, stent patency was comparable at 1 year. There was inconsistency in the use of validated tools for the measurement of symptoms before and after intervention. When reported, venous claudication, improved in 83% of PTS patients and 90% of NIVL patients, and ulcer healing occurred in 80% of PTS patients and 32% of NIVL patients. CONCLUSIONS: The first generation of dedicated venous stents perform comparably in terms of patency and clinical outcomes to non-dedicated technologies at 1 year for the treatment of patients with NIVL and PTS. However, significant heterogeneity exists between studies and standardized criteria are urgently needed to report outcomes in patients undergoing deep venous stenting.