Self-expandable Stent Placement Research Articles

Hemodynamic instability during carotid artery stenting: the relative contribution of stent deployment versus balloon dilation

Hemodynamic instability may complicate carotid angioplasty and stenting in up to 40% of patients. The authors have previously demonstrated that primary self-expanding stent placement alone can gradually dilate severely stenosed carotid arteries without the use of balloons. The authors hypothesized that eliminating the balloon would reduce carotid baroreceptor stimulation, thereby decreasing the incidence of hemodynamic instability. Ninety-seven high surgical risk patients with symptomatic, severely stenosed carotid arteries were treated with the intention of using a self-expanding stent alone. Seventy-seven arteries (79%) were treated with stenting alone, and 20 required angioplasty (21%). Intraprocedural bradycardia (heart rate < 60 bpm) developed in 29 patients (38%) and hypotension (systolic blood pressure < 90 mm Hg) occurred in 1 patient (1%) treated with stenting alone. Fourteen patients (70%) who underwent angioplasty and stenting had bradycardia, and hypotension developed in 4 (20%). Atropine, glycopyrrolate, or vasopressors were required in 8% of patients who received stenting alone, compared to 30% of patients who underwent angioplasty. In the first 24 hours after treatment, hypotension or bradycardia developed in 25 patients (32%) who had undergone stent placement alone, and in 15 patients (75%) after stent placement and balloon angioplasty. There was no difference in the occurrence of intra- or postprocedural hypertension (systolic blood pressure > 160 mm Hg) between patients treated with stenting alone or stenting and balloons. Factors independently associated with hemodynamic depression included baseline heart rate and balloon use. Hemodynamic instability during and after carotid artery stenting was observed more frequently when balloon angioplasty was required than when stent placement was performed without concurrent balloon angioplasty.

Placement of Self-Expanding Metal Biliary Stents (SEMS) in Patients with Resectable Pancreatic Cancer

Placement of Self-Expanding Metal Biliary Stents (SEMS) in Patients with Resectable Pancreatic Cancer

Cardiac Arrest Caused by Tension Pneumomediastinum in a Boerhaave Syndrome Patient

This report presents a 23-year-old man with esophageal perforation, tension pneumomediastinum, and subsequent cardiorespiratory arrest. Initial resuscitation by cervical and subxiphoid mediastinotomy was ineffective. Bedside decompression of the posterior mediastinum through the esophageal hiatus of the diaphragm resulted in immediate return of a normal sinus rhythm and noncompromised mechanical ventilation. The patient made a full recovery and was discharged on day 12. Transhiatal decompression of the posterior mediastinum can be recommended for the treatment of cardiorespiratory complications in patients with tension pneumomediastinum in whom the classic cervical and subxiphoid mediastinotomies are ineffective.

Endovascular occlusion of intracranial wide-necked aneurysms with stenting (Neuroform) and coiling: mid-term and long-term results

Coiling associated with placement of self-expandable intracranial stents has amplified the treatment of intracranial wide-necked aneurysms, but the durability of this treatment and the existence of delayed recurrence are not yet well known. The purpose of this report is to present our experience with the Neuroform Stent associated with coiling and to evaluate complications, effectiveness, and long-term results of this technique. A retrospective study of 42 patients with wide-necked cerebral aneurysms treated with the Neuroform Stent was performed. Mean aneurysm size was 11.3 mm. Mean neck size was 5.33 mm. All patients were treated with coiling and stenting. Clinical and angiographic follow-up was available in 38 patients (90.5%). The overall follow-up time ranged from 6 months to 5 years (mean, 42 months), but most of the patients (92%) had a follow-up period superior to 1 year. Successful deployment of 41 stents (97%) was obtained. Permanent procedural morbidity was observed in only one patient (2.4%). Long-term complete aneurysmal occlusion was obtained in 27 patients (71%). Aneurysmal regrowth was observed in four patients (9.5%) on the first control angiogram. After the first control angiogram, no delayed recanalization or regrowth was observed. During the follow-up period, there were no hemorrhagic events, no delayed thrombosis, and no stent displacement. Our results demonstrate the effectiveness of the technique, a small rate of procedural complications, and long-term tolerance of the Neuroform Stent. Despite some evidence of early aneurysmal recurrence, long-term durability of stent-assisted aneurysm occlusion is stable after the first year.

Self-expanding Stent Placement as a Bridge for Safe Hepatic Chemoembolization in a Patient with Isolated Spontaneous Dissection of the Celiac Artery

Self-expanding Stent Placement as a Bridge for Safe Hepatic Chemoembolization in a Patient with Isolated Spontaneous Dissection of the Celiac Artery

EUS-guided self-expandable stent placement in 1 step: a new method to treat pancreatic abscess

EUS-guided self-expandable stent placement in 1 step: a new method to treat pancreatic abscess

Fatal Pericardial Tamponade After Superior Vena Cava Stenting

We discuss a fatal complication of percutaneous superior vena cava (SVC) self-expandable stent placement in a patient with superior vena cava syndrome (SVCS). The SVCS was caused by a malignant mediastinal mass with total occlusion of the SVC. Twenty-four hours after the procedure, the patient died of a hemopericardial tamponade. In the literature, only seven cases have been described with this life-threatening complication. Patients with a necrotic tumor mass are more likely to develop this complication. Knowledge of this complication may increase patient survival.

Expandable Stents for Malignant Dysphagia

Esophageal carcinoma is a common disorder with an overall 5-year survival rate of only 13%. Since most patients with incurable esophageal cancers live approximately six months, the main goal of treatment remains palliative relief of dysphagia and closure of tracheoesophageal fistulae (if present), while maintaining adequate peroral nutrition and quality of life. Endoluminal stenting is now considered to be the most effective and widely adopted method of palliation. Self-expanding metal stents (SEMSs) and self-expanding plastic stents (SEPSs) are easily deployed and highly effective in rapidly improving dysphagia and in sealing tracheoesophageal fistulae. Stents have been shown to be extremely useful for palliating malignant dysphagia resulting from primary esophageal tumors as well as from extraesophageal malignancies that cause external compression at any level of the esophagus. This article reviews endoscopic techniques of self-expanding esophageal stent placement in the treatment of malignant dysphagia.

Palliative treatment of malignant esophageal stenosis: the role of self-expanding stent endoscopic implantation

Endoscopic tube implantations were carried out in 40 patients with malignant stenosis of the esophagus and gastric cardia using self-expanding metallic stents. The indications for endoscopic intubation were the advanced stage of the tumor in 27 cases and risk factors that made resection inadvisable in 13 cases. In three patients, it proved impossible to implant a stent endoscopically because we were not able to pass the guide wire through the stenosis, whereas correct stent placement was achieved in 37 cases. Functional results were good in 33 patients, but four patients did not show any improvement of symptoms. Complications occurred in nine patients (24.3%): two bleedings, three neoplastic obstructions, one food obstruction, and three distal dislodgements of the prosthesis were observed, but could be readily corrected. No deaths occurred. The median survival time was 151 days (range 25-545 days). This study suggests that endoscopic placement of metallic self-expanding stents is safe and is to be preferred to plastic stents for easier implantation and lower morbidity.

Covered Self Expandable Metal Stents in Border-Line Resectable Pancreatic Carcinoma: Prospective Study Concerning Effectiveness and Safety

Aims: Placement of biliary self expandable metal stents (SEMS) in patients with pancreatic carcinoma suitable of surgical treatment has been controversial. Since covered SEMS (SEMSc) became available, the possibility of inserting these stents in potentially surgical patients is safer as they can be removed if necessary in 85-95% of cases. The aim of this study is to assess the effectiveness and safety of SEMSc in patients with malignant jaundice secondary to border-line resectable pancreatic carcinoma. Material and Method: 33 consecutive patients (23 m/10f; age 69.1 yrs) with obstructive jaundice secondary to border-line resectable pancreatic carcinoma (superior mesenteric vein invasion,large tumor, retroperitoneal growth) were included in the study. After biliary drainage with a SEMSc,patients underwent neoadjuvant treatment with gemcitabin and radiotherapy during 8 weeks. Patients were reevaluated after treatment by CT scan and tumors staged as unresectable or potentially resectable. In those patients harbouring potentially resectable tumors surgery was indicated. Effectiveness in jaundice palliation, accomplishment of neoadjuvant therapy and stent removal requirements during presurgical period were assessed. Stent related postsurgical complications were also evaluated. Results: SEMSc could be inserted in all patients although in one case the stent had to be removed 72 hours after placement due to acute cholecystitis (3%). 32 patients completed oncologic treatment with no toxicity related to the stent. After CT reevaluation,21 patients (65.6%) were considered unsuitable for surgery and 11 patients (34.4%) candidates for tumor resection. Bilirubin levels dropped from 15.3 to 1.1 mg/dl (p < 0.01) in surgical patients with no episodes of cholangitis. In 4 of the 11 patients stent removal was indicated prior to surgery to assure bilioenteric anastomosis. It was successfully performed in all patients with a polypectomy snare after a mean post insertion period of 11.5 weeks. At operation,4 patients were not resected due to peritoneal disease and 7 patients finally resected (21.9%). Cholangitis pathological features were present in all surgical specimens but clinical cholangitis or anastomotic fistula were not registered during postoperative follow up in any patient. Conclusions: 1. SEMSc are effective in presurgical jaundice palliation in patients with border-line resectable pancreatic carcinoma. 2. These stents allow neoadjuvant oncologic treatment accomplishment without any added toxicity. 3. The possibility of stent removal when needed is a remarkable advantage in terms of safety. 4. Postoperative complications do not increase in relation to presurgical SEMSc insertion.

Stent Fracture and Reocclusion After Placement of a Single Self-Expanding Stent in the Common Iliac Artery and Endovascular Treatment

We present a case of fracture of a single self-expanding stent placed in the common iliac artery (CIA). An 80-year-old woman underwent placement of a self-expanding stent for CIA occlusion. Stent fracture and reocclusion were detected after 18 months. Successful revascularization was achieved using a stent-in-stent maneuver. The possibility of stent fracture with reocclusion should be considered following treatment with a single self-expanding stent for CIA occlusion.

Self-Expandable Stent Placement in Infrapopliteal Arteries After Unsuccessful Angioplasty Failure: One-Year Follow-up

The purpose of this prospective study was to evaluate whether stent placement in infrapopliteal arteries is helpful in failed percutaneous transluminal angioplasty (PTA). Infrapopliteal PTA was performed in 70 arteries of 66 patients with chronic critical lower limb ischemia. The group comprised 55 males and 11 females, with an average age of 63.4 (range, 42-82) years. Diabetes mellitus was present in 92.4% of patients. Only the palpable anterior tibial and posterior tibial arteries were evaluated. Stents (Xpert stent; Abbot Vascular, Redwood City, CA, USA) were placed in 16 arteries where PTA was not successful (the failure was defined as residual stenosis >30% after PTA). In 54 arteries simple PTA was performed and was technically successful. Twenty-four nondilated arteries with no significant stenosis served as a comparison group. The 12-month patency rate was evaluated according to a combination of palpation and Doppler ultrasound. In all cases stent placement restored the flow in the artery immediately after unsuccessful PTA. Twelve-month follow-up showed a patency rate of 82% in the PTA group, 78% in the stent group, and 69% in the comparison group. We conclude that stent placement in the case of unsuccessful infrapopliteal PTA changed technical failure to success and restored flow in the dilated artery. At 12-month follow-up the patency rate of infrapopliteal arteries stented for PTA failure did not differ significantly either from nonstented arteries with an optimal PTA result or from a comparison group of nonintervened arteries.

Self-Expandable Polytetrafluoroethylene (PTFE)-covered Nitinol Stent for the Palliative Treatment of Malignant Biliary Obstruction

Purpose: We wanted to determine the technical and clinical efficacy of placing a self-expandable PTFE-covered nitinol stent for the management of inoperable malignant biliary obstruction. Materials and Methods: Thirty six patients with inoperable malignant biliary obstructions were treated by placement of self-expandable PTFE-covered nitinol stents (S & G Biotech Corporation, Seongnam, Korea). Clinical evaluation was done with assessment of the serum bilirubin and alkaline phosphatase levels, which were measured before and after stent placement within 1 week, at 1 month and at 3 months. The patient survival rate and stent patency rate were calculated with performing Kaplan-Meier survival analysis. Results: Successful stent placement was achieved in all the patients without procedure-related complication. Pancreatitis as an early complication occurred in two cases. The serum bilirubin and alkaline phosphatase levels were significantly decreased after the procedure. During the follow-up, recurrent obstructive jaundice occurred in six cases; stent migration occurred in four cases and tumor overgrowth occurred in two cases. The survival rates were 97%, 80%, 67% and 59% at 1, 3, 6 and 9 months, respectively. The stent patency rates were 96%, 92%, 86% and 86% at 1, 3, 6 and 9 months, respectively. Conclusion: Self-expandable PTFE-covered nitinol stent placement seems to be technically feasible and effective for the palliative treatment of malignant biliary obstruction.

Primary Self-Expandable Nitinol Stent Placement in Focal Lesions of Infrarenal Abdominal Aorta: Long Term Results

To evaluate the technical and clinical success, safety and long term results of percutaneous transluminal angioplasty/self-expandable nitinol stent placement of infrarenal abdominal aorta focal lesions. Eighteen patients underwent PTA of focal atherosclerotic occlusive disease of distal abdominal aorta. Two symptomatic occlusions and 16 stenoses in 10 male and 8 female patients (mean age 68.2 years) were treated with primary self-expandable nitinol stent placement. Primary self-expandable nitinol stent placement was technically successful in all 18 procedures; clinical success was achieved in 100% of patients. No complications associated with the procedure occurred. During the 49.4 months of mean follow up (range 3-96, 4 months) all treated aortic segments remained patent. Endovascular treatment (primary self-expandable nitinol stent placement) of focal atherosclerotic lesions of distal abdominal aorta is a safe method with excellent primary technical and clinical success rates and favourable Long term results.

Fracture of a Nitinol Carotid Artery Stent That Caused Restenosis

The placement of self-expanding nitinol stents in the carotid artery is rapidly emerging as a minimally invasive alternative in the treatment of cervical carotid artery occlusive disease. Fractures of balloon-expandable stents after placement in the carotid artery have been previously documented. The authors report on a single case of early stent fracture and complete mid-body disruption of a self-expanding stent associated with a significant restenosis necessitating repeat intervention after carotid artery stent placement for a de novo atherosclerotic lesion.

Delayed Complications after Placement of Self-Expanding Stents in Malignant Esophageal Obstruction: Treatment Strategies and Survival Rate

Placement of self-expanding metal stents is regarded as a safe and effective treatment in patients with incurable malignant esophagogastric obstruction. However, proceeding and possible benefit of re-interventions in patients with recurrent dysphagia due to delayed complications (>4 weeks after stent insertion) is unclear. In 133 patients with malignant stricture of the esophagus or the esophagogastric junction 164 expandable metal stents were placed. About 89 patients were followed up until death. All tumor- or stent-related complications and consequent re-interventions were recorded. The overall incidence of delayed complications was 53.4% (71 of 133 pts.), with 34 patients (25.6%) experiencing more than one complication. Recurrent dysphagia due to tumor ingrowth (22%) or overgrowth (15%), bolus obstruction (21%), stent migration (9%), and development of esophagorespiratory fistula (9%) was successfully treated by dilatation (24%), placement of a second/third stent (27%), laser therapy (16%), and/or placement of a feeding tube (PEG, 19%). The median survival of patients with endoscopic therapy was significantly longer (222 +/- 26 days) compared to patients without re-intervention (86 +/- 14 days, P < 0.0001). Delayed complications after metal stent placement for malignant esophageal stricture are common, but can be treated successfully by endoscopic re-intervention in most cases. Regular interventional therapy may also improve survival.

Minimizing Endoscopic Complications: Endoluminal Stents

Almost all endoluminal stents used by gastroenterologists in the United States are self-expandable metal stents, and they are placed most commonly for relief of malignant luminal obstruction. Recently, a plastic self-expandable stent was approved for treating refractory benign esophageal strictures. Endoluminal stent placement is associated with myriad of complications. Some of these complications can be avoided or minimized by the endoscopist, whereas others are beyond the endoscopist's control. This article covers the various complications that can occur following self-expandable stent placement and provides recommendations on how to minimize these complications.

Self-expanding Polyflex plastic stents in esophageal disease: various indications, complications, and outcomes

Esophageal stenting has become an important technique in the treatment of different clinical problems such as malignant or benign stenosis, anastomotic leaks after surgery, or fistulas. In this study we present our experience with the self-expanding Polyflex plastic stent in various indications, arising complications, and patient's outcomes. Over a three-year period, 35 patients underwent self-expanding Polyflex plastic stent placement for esophageal stenosis (n = 23) with 22 malignant, and for perforations, fistulas, or anastomotic leaks after surgery (n = 12). The short-term efficacy and long-term outcomes were analyzed. In patients with stenosis, implantation was performed without any complications in 91% (21/23). In one patient perforation occurred while passing the stenosis; in another patient the stent dislocated during the insertion procedure. Dysphagia score improved from 3.0 to 1.0 after stenting. In all patients with perforations, fistulas, or anastomotic leaks (n = 12), stents were placed successfully without any complication. Complete sealing of the mucosal defect was proven by radiography in 92% (n = 11) and healing was seen in 42% (n = 5). If indicated, stent removal was performed without any complications. Stent migration (n = 13; 37%) was the most common long-term complication. The placement of self-expanding Polyflex plastic stents is a highly sufficient and cost-effective treatment for malignant and benign esophageal disorders. Because the long-term results were highly favorable, self-expanding plastic stent placement could be used as the initial treatment for various conditions.

Long-Term Results after Placement of Aortic Bifurcation Self-Expanding Stents: 10 Year Mortality, Stent Restenosis, and Distal Disease Progression

To retrospectively evaluate the 10 year follow-up results in patients who had "kissing" self-expanding stent aortic bifurcation reconstruction. Forty-three patients were treated with "kissing" self-expanding stents for aortoiliac occlusive disease. Early follow-up with clinical and ankle brachial pressure indices (ABPI) was performed at 3, 6, 12, and 24 months and with intra-arterial digital subtraction angiography at 12-24 months; clinical and angiographic follow-up was performed for symptom recurrence up to 10 years after treatment. Retrospective record review was performed to assess mortality, clinical patency, angiographic patency, and secondary assisted patency of both stents and downstream peripheral vessels at 5 and 10 years follow-up. The 2 year primary angiographic and secondary assisted stent patencies were 89% and 93%, respectively. At 10 years follow-up in 40 patients the mortality was 38% (due to myocardial infarction, stroke, chronic renal failure, malignancy, and liver failure). At 5 and 10 years follow-up the primary clinical stent patency was 82% and 68%, and the secondary assisted stent patency 93% and 86%, respectively. At 5 and 10 years, the distal vessel patency was 86% and 72%, and the secondary assisted distal vessel patency treated by surgical or endovascular techniques was 94% and 88%, respectively. At 10 years there was no limb loss. The long-term (10 year) results of aortic bifurcation arterial self-expanding stent placement in patients with arterial occlusive disease show a 10 year primary stent patency rate of 68% but a secondary assisted patency rate of 86%. In addition there is a high overall mortality due to other cardiovascular causes and the rate of distal disease progression and loss of patency is similar to the loss of stent patency rate.

Malignant Duodenal Obstructions: Palliative Treatment Using Self-Expandable Nitinol Stents

To assess the efficacy of fluoroscopic per oral placement of self-expandable nitinol stents in the palliative treatment of malignant duodenal obstructions. Under fluoroscopic guidance, 82 patients (56 male and 26 female; mean age, 62.3 y) with malignant duodenal obstructions were treated with per oral placement of four types of self-expandable nitinol stents. All patients presented with severe nausea and recurrent vomiting, and their obstructions were inoperable. Technical success was achieved in 78 of 82 patients (95.1%). After stent placement, food intake capacity improved in 74 of 78 patients (94.9%). Stent migration occurred in one patient 4 days after placement. A covered stent was placed to cover the ampulla of Vater in 15 patients without external biliary drainage; three of them (20%) became jaundiced. During the mean follow-up period of 74.7 days (range, 9-374 d), eight patients developed recurrent obstructive symptoms caused by tumor ingrowth (n=2) or tumor overgrowth (n=6). They were successfully treated by additional stent placement. The primary stent patency rates were 97.0%, 79.8%, and 44.0% at 30-, 90-, and 180 days, respectively (mean patency, 228.2 d; 95% CI, 153.9-302.5). Fluoroscopic per oral placement of self-expandable nitinol stents is an effective palliative treatment for malignant duodenal obstructions.