Case report: intracoronary stent fracture complicated with coronary abscess and fistulization into the pericardium.

Background: Stent fractures are a rare complication of angioplasties and are an unusual substrate for coronary abscesses. Case summary: A 63-year-old patient came into the emergency department for ongoing chest pain. The patient had recently undergone coronary stent implantation, 3 months prior. Computed tomography coronary angiography revealed a coronary abscess and stent fracture, with blood effraction into the pericardium. The patient underwent emergency open-heart surgery to clear the infection and perform coronary artery bypass graft surgery. Post-operative outcome was tentatively favourable. The patient suffered acute kidney injury and required haemodialysis. Discussion: Coronary stent fracture is a rare complication which can be life-threatening and which can lead to severe sequelae.

Comparison of Biomechanical Properties of the iCover and VBX Stent Grafts When Used as Bridge Stents in Fenestrated Endografts: An In Vitro Study.

OBJECTIVE: The objective of this study was to compare in vitro the different biomechanical properties of 2 balloon-expandable covered stents, VBX (Viabahn VBX, W.L. Gore & Associates, Flagstaff, AZ) and iCover (iVascular, Barcelona, Spain), as bridging stents in fenestrated aortic endoprostheses. METHODS: Three biomechanical tests were performed to evaluate a total of 12 stents (6 VBX 6 × 59 mm and 6 iCover 6 × 57m). First, a 3-point bending test was performed with a calibrated dynamometer to evaluate the bending strength of the 40% and 150% deformation of the system in its crimped state and the force necessary to deform the expanded stent by 40% with respect to its initial diameter. Then the stents were expanded to their nominal diameter inside a 6-mm-diameter handmade fenestration and flared up to 8 and 10 mm. The whole set was fixed in the dynamometer to carry out the pullout-force (perpendicular dislocation) and shear-stress-force (axial dislocation) tests. The resulting forces were recorded via the force transducer. Load, deformation, and displacement data were recorded in newtons. The results of each stent test were examined under the microscope, and both stent types were compared. RESULTS: Higher forces were required to bend the crimped VBX (16.24 N [IQR, 13.87-17.47 N] for the iCover and 19.01 N [IQR, 16.01-19.50 N] for VBX; P < 0.001), but lower forces were necessary for the expanded VBX compared with the iCover (0.36 N [IQR, 0.1-0.49 N] and 1.01 N [IQR, 0.97-1.09 N], respectively; p = 0.004). Pullout forces were 3.56 N (IQR, 3-4.1 N) and 7.07 N (IQR, 6.86-7.28 N) for the 8-mm flare and 7.29 N (IQR, 6.13-8.45 N) and 14 N (IQR, 12.05-15.95 N) for the 10-mm flare for the iCover and VBX, respectively (P = 0.333 for both comparisons). The shear-stress forces needed to dislocate the 6-mm iCover and VBX axially with a 10-mm flare to 50%, 100%, and 200% were 0.88, 1.61, and 3.55 N for the iCover and 0.71, 1.43, and 2.51 N for the VBX (P = 0.343, P = 0.486, and P = 0.486, respectively). CONCLUSION: After evaluating the stents under in vitro conditions, the VBX and iCover stents showed similar results in terms of biomechanical properties, which demonstrates their competence in in vitro conditions. Further in vitro comparisons with other stent grafts are required. CLINICAL IMPACT: The BECS used in FEVAR / BEVAR must ensure some properties to avoid the most frequent complications derived from the failure of these bridging stents (stenosis, thrombosis, stent integrity, dislodgement or endoleaks) that represent the most common cause for reintervention. This paper adds to the limited data available, information to the clinician after comparing some properties of two BECS used in these techniques that demonstrate their competence in in-vitro conditions.

Systematic Review of Femoral Artery Stent Fractures.

Objective: Primary stenting for long femoropopliteal (FP) lesions remains controversial because of the high risk of stent fracture (SF). This study aimed to summarise current knowledge on SF from randomised control trials about FP stenting. Methods: A systematic review of the Medline database was performed by a combined strategy of MeSH terms: femoral artery, popliteal artery, stenting, and stent fracture. SF was classified according to a standard classification: 1 = single strut fracture; 2 = ≥ two struts fracture; 3 = type 2 with deformation; 4 = multiple struts fracture with acquired transection; 5, type 4 with gap in the stent body. Results: The literature search identified 25 publications including covered stents (CSs; n = 3), drug eluting stents (DESs; n = 8), bare metal stents (BMS; n = 17), and bioabsorbable stents (n = 1). Data were extracted from 4 047 patients; mean age ± standard deviation was 68.9 ± 3.0 years and 69% were male. The median lesion length was 87.6 mm (interquartile range [IQR] 70.0, 149) with a median chronic total occlusion proportion of 36.8% (IQR 29.0, 56.5). In 208 patients treated with CS, SF rates ranged from none to 2.6% at 36 months with no clinical correlation. In 1 106 patients treated with DES, SF rates were relatively low in large cohorts, ranging from 0% at 12 months to 1.9% at 60 months. In smaller cohorts (under 100 patients per group), they ranged from 12.5% at six months to 46.7% at 12 months, with no clinical repercussion. In 1 610 patients treated with BMS, SF rates ranged from 2% to 32.7% at 12 months and from 2.9% to 48.9% at 24 months, with no clinical repercussion. Conclusion: SF rates in large cohorts were low in CF and DES, and quite common in BMS, although none of them had clinical consequences. However, longer follow up and detailed, accurate reports are needed to assess eventual real clinical outcomes.

Non-invasive recanalization of first-generation sirolimus-eluting stent thrombosis due to stent fracture and coronary artery aneurysm after clopidogrel treatment 15 years after implantation.

In 2020, a 48-year-old male patient was admitted to our hospital due to unstable angina. In 2005, three first-generation sirolimus-eluting stents (1st-SESs) had been deployed to his right coronary artery (RCA). Over the past 10 years or so, the patient has been treated with single antiplatelet therapy using aspirin. Coronary angiography (CAG) revealed severe stenosis in the left circumflex artery (LCx) and total occlusion at the proximal portion of the stented RCA. Furthermore, fluoroscopy showed multiple 1st-SES fractures. After ad hoc percutaneous coronary intervention of the LCx, dual antiplatelet therapy (DAPT) was resumed by adding the P2Y12 inhibitor clopidogrel to aspirin. Two months later, CAG revealed complete recanalization and multiple peri-stent coronary artery aneurysms (CAAs) in the RCA. Intravascular ultrasound revealed late-acquired stent malapposition (LSM) and formation of true aneurysms. Coronary angioscopy showed the uncovered struts of the 1st-SES and mural red thrombus. DAPT was continued thereafter, and 8 months later, follow-up CAG showed no significant RCA restenosis. To date, the patient remains free from cardiovascular events. This report documents a rare case of thrombotic occlusion of a 1st-SES with LSM, CAA, and stent fractures followed by non-invasive recanalization after clopidogrel treatment 15 years after 1st-SES implantation. Learning objective: Stent thrombosis due to stent fracture and coronary aneurysm can occur even years after first-generation sirolimus-eluting stent (1st-SES) implantation. Risk assessment using coronary imaging should be made and long-term dual antiplatelet therapy (DAPT) should be recommended in patients with a high risk of stent thrombosis after 1st-SES implantation. In cases of stent thrombosis of the 1st-SES, resuming DAPT, including P2Y12 receptor inhibitors, may be a useful non-invasive treatment option.

Left subclavian artery bridging stent fracture after in-situ laser fenestration during emergent thoracic endovascular aortic repair.

In-situ laser fenestration (ISLF) has been described as a viable option for urgent thoracic aortic aneurysm cases involving supra-aortic vessels. There are, however, limited data on its durability. Here, we present a case of a 70-year-old man with a symptomatic 13-cm thoracic aortic aneurysm extending proximally to the origin of the left subclavian artery (LSA). Emergent thoracic endovascular aortic repair with chimney stenting of the left common carotid artery and ISLF for the LSA was successfully performed. During the follow-up, a compression of the bridging stent to the LSA progressed to a stent fracture needing realignment. Despite ISLF's reported technical success, this case highlights the risk of bridging stent complications, emphasizing the need for a close follow-up.

A case of repeated stent fracture.

Stent fracture is one of the complications of drug-eluting stent implantation. An 84-year-old man underwent coronary angiography for unstable angina. He had diffuse severe stenosis and calcified plaque in the left anterior descending artery and underwent percutaneous coronary intervention (PCI) in the left anterior descending artery for severe stenosis with chest pain. Thereafter, two subsequent stent fractures occurred, so the patient underwent another PCI to cover them. However, a stent fracture was found again one year later. The patient was asymptomatic and PCI was avoided due to the risk of further stent fracture. When a stent fracture occurs, it is important to provide appropriate treatment according to the anatomical findings of the vessel, symptoms and the presence of ischemia.

Asymptomatic Complete Spiral Stent Fracture in Subclavian Artery with Progressive Restenosis in the Early Postoperative Period: A Case Report.

Objective: Stent fractures may be a risk factor for delayed restenosis, but it is difficult to diagnose asymptomatic stent fractures in the subclavian artery (SCA). We report a rare case of percutaneous transluminal angioplasty and stenting (PTAS) for SCA stenosis with asymptomatic severe stent fracture that showed progressive in-stent stenosis in the early postoperative period. Case Presentation: A 70-year-old woman presented with left arm claudication. Magnetic resonance imaging at the time of admission showed SCA stenosis with severe calcification. Because of the left subclavian steal phenomenon on ultrasonography of the left vertebral artery, she underwent PTAS using a balloon-expandable stainless stent. Ultrasonography the day after treatment showed appropriate stent placement. Computed tomography angiography (CTA) 30 days after PTAS showed an asymptomatic complete spiral stent fracture at the mid-portion of the stent. The in-stent stenosis then gradually progressed on follow-up ultrasonography at the site of the stent fracture. Nine months after the first PTAS, a second PTAS using a self-expandable nitinol stent was performed because the peak systolic velocity exceeded 300 cm/s on Doppler ultrasound. Two years after the second PTAS, no neurological symptoms and no stent deformation were observed. Conclusion: PTAS with a balloon-expandable stainless stent for SCA stenosis with severe calcification may lead to stent fracture. In the case of severe stent fracture, careful follow-up may be needed for the detection of asymptomatic in-stent stenosis in the early postoperative period.

In-stent restenosis caused by a reprotruding calcified nodule and stent fracture in the hinged coronary artery.

Calcified nodules (CNs) cause in-stent restenosis (ISR) frequently. Although reprotrusion of CNs through stent struts is one of the mechanisms of ISR, the process of this phenomenon has not been understood. Furthermore, little is known about stent fracture (SF) occurring at the site of CNs. We are presenting a case of an 82-year-old male who developed early ISR due to the combination of an in-stent CN and SF in the hinged right coronary artery. The process of progression of the in-stent CN was recorded sequentially with angiography and intravascular ultrasound (IVUS). IVUS from the fulcrum of hinge motion revealed the repetitive protruding movement of the CN into the stent lumen.

Pulmonary Artery Stent Implantation.

Pulmonary artery stent implantation has become integral in the treatment of pulmonary artery stenosis and is probably the most efficacious therapy for these lesions. Advancements in technology involving stent design and the equipment used for stent delivery have made this procedure much safer and more effective. Strategies to mitigate and successfully treat adverse events related to pulmonary artery stent implantation are reasonably well-established. Pulmonary artery stent implantation remains one of the most complex and technically challenging of congenital cardiac interventions.

Esophageal Self-Expandable Metal Stents Can Fracture in the Distal Third When Used for Post-Bariatric Surgery Complications: A Single Center Experience and Review of the Literature with Video.

Background: Esophageal self-expandable metal stents (SEMS) are an important endoscopic tool. These stents have now been adapted successfully to manage post-bariatric surgery complications such as anastomotic leaks and strictures. In centers of expertise, this has become the primary standard-of-care treatment given its minimally invasive nature, and that it results in early oral feeding, decreased hospitalization, and overall favorable outcomes. Self-expandable metal stents (SEMS) fractures are a rare complication of unknown etiology. We aimed to investigate possible causes of SEMS fractures and highlight a unique endoscopic approach utilized to manage a fractured and impaled SEMS. Methods: This is a retrospective study of consecutive patients who underwent esophageal SEMS placement between 2015-2021 at a tertiary referral center to identify fractured SEMS. Patient demographics, stent characteristics, and possible etiologies of fractured SEMS were identified. A comprehensive literature review was also conducted to evaluate all prior cases of fractured SEMS and to hypothesize fracture theories. Results: There were seven fractured esophageal SEMS, of which six were used to manage post-bariatric surgery complications. Five SEMS were deployed with their distal ends in the gastric antrum and proximal ends in the distal esophagus. All stents fractured within 9 weeks of deployment. Most stents (5/7) were at least 10 cm in length with fractures commonly occurring in the distal third of the stents (6/7). The wires of a fractured SEMS were embedded within the esophagogastric junction in one case, prompting the use of an overtube that was synchronously advanced while steadily extracting the stent. Discussion: We suggest the following four etiologies of SEMS fractures: anatomical, physiological, mechanical, and chemical. Stent curvature at the stomach incisura can lead to strain- and stress-related fatigue due to mechanical bending with exacerbation from respiratory movements. Physiologic factors (gastric body contractions) can result in repetitive squeezing of the stent, adding to metal fatigue. Intrinsic properties (long length and low axial force) may be contributing factors. Lastly, the stomach acidic environment may cause nitinol-induced chemical weakness. Despite the aforementioned theories, SEMS fracture etiology remains unclear. Until more data become available, it may be advisable to remove these stents within 6 weeks.

Fracture and plastering of distal left main stent during double-kissing Culotte technique: a case report.

Background: Acute fracture of a left main (LM) stent during angioplasty is a rare complication. Cardiologists should be aware of the risk of stent fracture (SF) following kissing balloon inflation (KBI) even if the effective diameter of the balloons does not exceed the recommended expansion limits of stents. Case summary: A 64-year-old female with hypertension and dyslipidaemia presented with crescendo angina since three months in spite of optimal medical therapy. Coronary angiogram showed a distal LM bifurcation lesion. The patient was admitted for LM bifurcation stenting by upfront two-stent technique (inverted double-kissing Culotte technique). Following first KBI of the stent placed from left circumflex artery (LCX) to LM, there was stent deformation in the LM shaft. As we had planned the Culotte technique, we decided to exclude the fractured segment by stenting from left anterior descending artery (LAD) to LM. The stent from LAD-LM successfully excluded the fractured part of the first stent from the lumen of LM. Optical coherence tomography done after final KBI from LCX-LM revealed successful exclusion of the deformed segment of the LCX stent with mild malapposition at the site of the deformed stent. A follow-up angiogram after six months showed normal in-stent flow with no evidence of restenosis or pseudoaneurysm. Discussion: Acute LM SF during coronary intervention can occur even if the effective cumulative diameter of the inflated balloons does not exceed the mentioned expansion limit of stents. Intravascular imaging is a helpful modality to define type of SF and its management.

The Role of CT Imaging in a Fractured Coronary Stent with Pseudoaneurysm Formation.

We report a case of a 63-year-old male patient with multiple cardiovascular risk factors and previous myocardial infarction who was referred to the emergency department on September 2023 with symptoms and clinical and biological data consistent with an acute coronary event. A coronary angiography revealed severe ostial stenosis of the left anterior descending artery (LAD) and intrastent thrombotic occlusion in the first two segments of the LAD. Two drug-eluting stents were implanted and the patient was discharged when hemodynamically stable; however, three weeks later, he returned to the emergency department complaining of fever, anterior chest pain, dyspnea at rest, and high blood pressure values at home. High levels of troponin T, C-reactive protein, and NT-proBNP were detected and blood cultures showed methicillin-resistant Staphylococcus aureus. The computed tomography (CT) examination showed a saccular dilatation had developed between two fragments of a stent mounted at the level of the LAD, surrounded by a hematic pericardial accumulation. LAD pseudoaneurysm ablation and a double aortocoronary bypass with inverted saphenous vein autograft were performed and the patient showed a favorable postoperative evolution. In this case, surgical revascularization was proven to be the appropriate treatment strategy, demonstrating the need to choose an individualized therapeutic option depending on case-specific factors.

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.

Spontaneous Endoscopic Esophageal Stent Fracture Post-endoscopic Placement: A Case Report.

Endoscopic esophageal stent (EES) placement is an important tool for the non-operative management of esophageal pathologies. A rare and infrequently reported complication of EES placement is stent fracture and subsequent migration of the broken fragments. We report a rare case of a spontaneous EES fracture from Pakistan four weeks following its placement for esophageal perforation management, and an uneventful endoscopic retrieval of the fractured stent pieces. The recommended guidelines from available, albeit limited, research literature are also discussed as part of this case report.

Stent fracture after transjugular intrahepatic portosystemic shunt placement using the bare metal stent/stent-graft combination technique.

BACKGROUND: A transjugular intrahepatic portosystemic shunt (TIPS) is widely placed to treat portal hypertension. Because the Viatorr® stent (W. L. Gore and Associates, Flagstaff, AZ, United States) is not available in all hospitals in China, the bare metal stent (BMS)/stent-graft combination technique is still popular for TIPS construction. Stent fracture is a complication after TIPS placement using this technique, with limited available literature focusing on it. AIM: To assess the incidence of stent fracture after TIPS placement using the BMS/ stent-graft combination technique and to identify the risk factors for stent fracture. We proposed technique modifications to improve the clinical results of TIPS placement with the BMS/stent-graft combination technique. METHODS: We retrospectively analyzed the computed tomography (CT) data of all patients with portal hypertension who underwent the TIPS procedure between June 2011 and December 2021 in a single center. Patients implanted with the BMS/stent graft and had follow-up imaging data available were included. We identified patients with stent fracture and analyzed their characteristics. Multivariable logistic regression was applied to identify the potential predictors of stent fracture. RESULTS: Of the 68 included patients, stent fracture occurred in seven (10.3%) patients. Based on CT images, the stent fractures were categorized into three types. Our study consisted of four (57.1%) type I fractures, one (14.3%) type II fracture, one (14.3%) type IIIa fracture, and one (14.3%) type IIIb fracture. After adjusting for covariates, multivariable logistic regression revealed that the risk factors for stent fracture were the implantation of a greater number of stents [adjusted odds ratio (aOR) = 22.2, 95% confidence interval (CI): 1.2-415.4, P = 0.038] and a larger proximal sagittal stent bending angle (aOR = 1.1, 95%CI: 1.0-1.3, P = 0.020). CONCLUSION: Stent fracture occurred in approximately 10% of patients with portal hypertension who underwent TIPS with the BMS/stent-graft combination technique. The number of implanted stents and stent bending angle at the inferior vena cava end were predictors of stent fracture, which suggests that the incidence of stent fracture could potentially be reduced by procedural modifications.

Early stent fractures in superficial femoral artery resulting multiple pseudoaneurysm formation within one year: a case report.

BACKGROUND: Though fracture is known complication of stenting, pseudoaneurysm asscoiated with stent fracture is an extremely rare complication. This has previoulsy been described to occur at least one or more years following initial stent placement. Here we present a case of multi-site stent fracture leading to two separate SFA pseudoaneurysms within one year of placement, successfully treated with covered stents. CASE PRESENTATION: A 72-year-old male presented with severe claudication of his left lower extremity (Rutherford 3), found to have long segment SFA chronic total occlusion (CTO). Patient successfully underwent endovascular revascularization. Follow-up duplex ultrasound (US) at one year demonstrated a focus of severe in-stent restenosis (ISR). During repeat angiogram for treatment of the stenosis, stent fracture and pseudoaneurysm was seen in the distal SFA, which was treated successfully with a self-expanding covered stent. Additional stent fractures and pseudoanerusyms were subseuqently identified on follow-up, necessitating a third angiogram, and these were successfully repaired using overlapping covered stents, without further recurrence. CONCLUSIONS: Superficial femoral artery stent fractures leading to pseudoaneurysms are extremely rare, particularly within first year of stent placement. Endovascular repair with covered stents has proven to be an effective treatment option with decreased procedural morbidity compared to surgical repair.