nitinol and Hemorrhage

To report a novel technique for safely closing antegrade common femoral artery (CFA) punctures using the StarClose device after proximal superficial femoral artery (SFA) angioplasty.. The vessel locator of the StarClose device should not be deployed within a recently dilated vessel, so after proximal SFA angioplasty, the sheath is withdrawn into the CFA. A second guidewire is inserted into the profunda femoris artery followed by insertion of the StarClose sheath. The vessel locator is deployed in the profunda main stem and withdrawn into the CFA until resistance is felt, indicating apposition to the luminal aspect of the vessel wall. The device is subsequently deployed according to the manufacturer's instructions.. Use of profunda femoris artery allows safe closure of the CFA using the StarClose device following antegrade puncture for proximal SFA angioplasty.

Topics: Alloys; Angiography; Angioplasty, Balloon; Arterial Occlusive Diseases; Femoral Artery; Hemorrhage; Hemostatic Techniques; Humans; Punctures

Vascular complications during transcatheter aortic valve replacement (TAVR) still pose a significant concern regarding procedural safety. Designated closure devices for large-bore vascular access are needed.. Patients undergoing TAVR were prospectively enrolled into the study. The InSeal vascular closure device (VCD) achieves hemostasis by utilizing a crescent-shaped nitinol scaffold covered by a biodegradable membrane, which is delivered at the arterial puncture site. The coprimary endpoints were predefined as hemostasis within 15 min following vessel access site closure and after activated clotting time falls below 200 s and the rate of related major vascular adverse events in first month.. A total of 50 patients were prospectively enrolled into the study, with an average age of 80.8 ± 7.4 years and 62% males. Hemostasis with the Inseal VCD was achieved in 94% of the patients with average time-to-hemostasis of 51 ± 97 s. The rates of in-hospital vascular complications were 12% mostly driven by minor vascular complications (10%). Femoral artery stents were used in three patients due to failed hemostasis.. Initial clinical experience indicates that a novel, nitinol-based, large-bore vascular closure device is safe and effective in achieving hemostasis after TAVR.

Topics: Aged; Aged, 80 and over; Alloys; Arteries; Catheterization, Peripheral; Equipment Design; Female; Germany; Hemorrhage; Hemostasis; Hemostatic Techniques; Humans; Israel; Male; Prospective Studies; Punctures; Treatment Outcome; Vascular Access Devices; Vascular Closure Devices

Traumatic vascular injuries, resulting from either civilian accidents or wounded soldiers, require new endovascular devices (i.e., stent graft) to rapidly control the excessive internal hemorrhage in torso region. Current stent designs are limited by their permanent nature, which is note well suited for emergent placement. A retrievable stent graft could regulate the internal bleeding temporarily, as fast as possible with the most feasible performance, until the patients arrive the hospital to receive the proper treatment. The novel endovascular device of this study is designed according to the anatomy of a porcine model with plans to transition to a human model in the future. The stent graft is manufactured using a substantially long nitinol backbone and covered selectively based on anatomic measurements, with highly stretchable expanded-polytetrafluoroethylene (ePTFE). In this study, our group comprehensively explored designing and manufacturing methods, and their impact on the stent graft performance. Geometric parameters and heat treatment conditions were investigated to show their effect on the radial force of the metallic backbone. As a retrievable device, the resistance force for retrieval as well as deployment were measured, and analyzed to be manipulated through ePTFE covering configurations. In vitro measurements for bleeding were measured using swine aorta to show the functionality of the stent graft under the simulated pulsatile flow circulation. Finally, the stent graft showed substantial effectiveness for hemorrhage control in vivo, using swine model. The new design and fabrication methods enable rapid hemorrhage control that can be removed at the time of a dedicated surgical repair.

Topics: Alloys; Animals; Aorta; Blood Vessel Prosthesis; Hemorrhage; Humans; Mechanical Phenomena; Mechanical Tests; Polytetrafluoroethylene; Prosthesis Design; Risk Assessment; Stents; Swine; Torso; Treatment Outcome

Early hemorrhage control before the operating room is essential to reduce the significant mortality associated with traumatic injuries of the vena cava. Conventional approaches present logistical challenges on the battlefield or in the trauma bay. A retrievable stent graft would allow rapid hemorrhage control in the preoperative setting when endovascular expertise is not immediately available and without committing a patient to the limitations of current permanent stents. This study details a refined retrievable Rescue stent for percutaneous delivery that was examined in a porcine survival model of penetrating caval hemorrhage.. A retrievable caval stent was reduced in delivery profile to a 9F sheath using finite element analysis. The final stent was constructed with a "petal and stem" design using nitinol wire followed by covering with polytetrafluoroethylene. Seven Yorkshire pigs (79-86 kg) underwent 22F injury of the infrarenal vena cava with intentional class II hemorrhage (1200 mL). Percutaneous deployment of the Rescue stent was used to temporize hemorrhage for 60 minutes, followed by resuscitation with cell saver blood and permanent caval repair. Hemorrhage control was documented with photography and angiography. Vital signs were recorded and laboratory values were measured out to 48 hours postoperatively. Data were examined with a repeated-measures analysis of variance.. The profile of the caval Rescue stent was successfully reduced from 16F to 9F while remaining within fracture and shape memory limits for nitinol. In addition, both rapid deployment and recapture were preserved. Following intentional hemorrhage after caval injury, animals revealed a significant drop in mean arterial pressure (average, 30 mm Hg), acidosis, and elevated lactate level compared with before injury. Compared with uncontrolled hemorrhage, which resulted in death in <9 minutes, the Rescue stent achieved hemorrhage control in <1 minute after venous access in all seven animals. All animals were successfully recovered after permanent repair. There was no significant change in levels of transaminases, bilirubin, creatinine, or hemoglobin at 48 hours compared with preinjury baseline.. A retrievable Rescue stent achieved rapid percutaneous hemorrhage control after a significant traumatic injury of the vena cava and allowed successful recovery of all injured animals. Further development of this approach may have utility in preoperative damage control of caval injuries.

Topics: Alloys; Angiography; Animals; Endovascular Procedures; Finite Element Analysis; Fluorocarbon Polymers; Hemorrhage; Hemostasis, Surgical; Models, Animal; Prosthesis Design; Stents; Swine; Vena Cava, Inferior

To evaluate the efficacy and safety of the nitinol clip-based closure device (Starclose®, Abbott Vascular, Santa Clara, California) in patients with femoral arterial cannulation at the common femoral artery bifurcation.. Femoral artery puncture at the bifurcation of common femoral artery is a relative contraindication for the use of vascular closure devices with intravascular components, and patients with bifurcation cannulation were excluded from the pivotal trials of these devices. The nitinol clip-based closure device (Starclose) is extravascular and is sometimes used in such patients; however, the efficacy and safety of this approach is unknown.. We evaluated consecutive patients undergoing deployment of a Starclose device following a coronary procedure via the femoral artery approach. Quantitative femoral angiographic analyses were performed using a hand caliper. The distance of the artery puncture site from the bifurcation was recorded in each patient. Any arterial cannulation ≤ 3 mm from the bifurcation was categorized as a bifurcation cannulation (as the outer diameter of the nitinol clip of Starclose is 4 mm).. Among 1096 patients who underwent deployment of a Starclose device, 217 (20%) were within 3 mm of the bifurcation. Starclose deployment at the bifurcation was not associated with a significant increase in the risk of any (0.9% vs. 1.0%; p = 0.892) major (0.0% vs. 0.3%; p = 0.389) or minor vascular complications (0.9% vs. 0.7%; p = 0.711) compared to deployment for non-bifurcation cannulations (both for diagnostic and percutaneous coronary interventional procedures). The results were unchanged in both a regression model adjusted for a propensity score (41 baseline covariates) as well as a propensity score-matched cohort (217 bifurcation cannulations vs. 217 non-bifurcation cannulations).. In a select group of patients, vascular closure using a extravascular closure device (Starclose) appears to be safe for arterial cannulations at or near the bifurcation.

Topics: Aged; Alloys; Angiography; Cardiac Catheterization; Case-Control Studies; Cohort Studies; Female; Femoral Artery; Hemorrhage; Hemostatic Techniques; Humans; Logistic Models; Male; Middle Aged; Outcome Assessment, Health Care; Propensity Score; Retrospective Studies; Surgical Instruments; Treatment Outcome; Wound Closure Techniques

Topics: Alloys; Cardiac Catheterization; Femoral Artery; Hemorrhage; Hemostatic Techniques; Humans; Outcome Assessment, Health Care; Propensity Score; Surgical Instruments; Treatment Outcome; Wound Closure Techniques

Diagnostic cardiac catheterizations are predominantly performed using access through the femoral artery. To improve patient comfort and early mobilization, a number of percutaneous closure devices have been developed. One such device using the nitinol clip was developed by Abbott Vascular Devices and was approved for use on the basis of the results of the Clip Closure In Percutaneous Procedures (CLIP) study. The safety of repuncture through a previously deployed device has not been established in humans. We present the case of a patient who had an arterial line placed for post-operative monitoring after cardiac surgery at the site of a previous arteriotomy closed with the Starclose device. The catheter traversed through the central portion, tethered to the periphery of the ninitol clip, and required surgery for extraction.

Topics: Aged; Alloys; Cardiac Catheterization; Cardiac Surgical Procedures; Catheterization, Peripheral; Device Removal; Equipment Design; Femoral Artery; Foreign-Body Migration; Hemorrhage; Hemostatic Techniques; Humans; Male; Postoperative Care; Punctures; Radiography; Treatment Outcome; Vascular Surgical Procedures

Topics: Alloys; Cardiac Catheterization; Catheterization, Peripheral; Equipment Design; Femoral Artery; Foreign-Body Migration; Hemorrhage; Hemostatic Techniques; Humans; Punctures

A patient was fitted with an Anaconda stent graft for which there was a persistent type II endoleak. Two subsequent attempts at embolization were unable to resolve the endoleak. The diameter of the aneurysm varied initially from 5.5 cm in diameter down to 4.8 cm but then later re-dilated to 6.1 cm, with evidence of persistent flow into the aneurysmal sac from the inferior mesenteric artery. Results from serial computed tomography scans demonstrated clear evidence of a type II endoleak that originated from the inferior mesenteric artery with outflow to a distal lumbar artery. The harvested stent graft did not show evidence of a device-related failure. The stent graft and its modular segments were found to have been properly deployed. Only a thin external capsule was evident at explantation. The internal wall of the device showed irregular and thin encapsulation with scattered mural thrombi, which were more prominent at the bifurcation of the main body of the device. Blood deposits and tissue development were sufficient to prevent blood oozing through the wall. The explanted Anaconda stent graft was devoid of any construction flaws or damage (fatigue of the textile or corrosion of the Nitinol wires) after implantation.

Topics: Alloys; Aortic Aneurysm, Abdominal; Biocompatible Materials; Blood Vessel Prosthesis; Device Removal; Equipment Failure Analysis; Hemorrhage; Humans; Materials Testing; Microscopy, Electron, Scanning; Polypropylenes; Stents; Sutures; Tomography, X-Ray Computed

We describe a case of symptomatic common femoral artery stenosis following use of a vascular clip closure device (StarClose). Operative repair was performed, with removal of the clip device and subsequent vein patch angioplasty.

Topics: Adult; Alloys; Angioplasty; Arterial Occlusive Diseases; Constriction, Pathologic; Coronary Angiography; Device Removal; Equipment Design; Female; Femoral Artery; Hemorrhage; Hemostatic Techniques; Humans; Intermittent Claudication; Punctures

Topics: Alloys; Angioplasty; Arterial Occlusive Diseases; Constriction, Pathologic; Coronary Angiography; Device Removal; Equipment Design; Evidence-Based Medicine; Femoral Artery; Hemorrhage; Hemostatic Techniques; Humans; Intermittent Claudication; Patient Selection; Punctures; Risk Assessment

Topics: Alloys; Angioplasty, Balloon; Arterial Occlusive Diseases; Device Removal; Equipment Design; Femoral Artery; Foreign-Body Migration; Foreign-Body Reaction; Giant Cell Arteritis; Hemorrhage; Hemostatic Techniques; Humans; Patient Selection; Pressure; Punctures; Risk Factors; Skin Diseases; Ultrasonography

We report the first case of a transcutaneous migration of a vascular clip closure device 10 weeks after placement during femoral artery puncture for percutaneous transluminal angioplasty. We postulate focal inflammatory vascular wall changes as the predisposing factor in this patient with giant cell arteritis.

Topics: Aged; Alloys; Angioplasty, Balloon; Arterial Occlusive Diseases; Device Removal; Equipment Design; Female; Femoral Artery; Foreign-Body Migration; Foreign-Body Reaction; Giant Cell Arteritis; Hemorrhage; Hemostatic Techniques; Humans; Punctures; Risk Factors; Skin Diseases; Ultrasonography

Hemorrhage caused by tumor invasion of the axillary artery is a rare, but serious complication. A 70-year-old female with a history of inflammatory breast cancer was diagnosed with hypovolemic shock caused by arterial bleeding into the left axilla. After successful reanimation an emergency arteriography was performed. The bleeding site was localized in the proximal part of the axillary artery. A self-expanding endoluminal graft was positioned across the lesion. The final angiography showed a correct placement of the stent with excellent distal flow, and no signs of bleeding. On the seventh day, the patient was discharged with ambulatory follow up.

Topics: Aged; Alloys; Angioplasty, Balloon; Axilla; Axillary Artery; Blood Vessel Prosthesis Implantation; Breast Neoplasms; Carcinoma; Female; Hemorrhage; Humans; Neoplasm Invasiveness; Radiography; Shock; Stents

Carotid blowout is a devastating complication in patients with head and neck malignancy. A covered stent offers an alternative to treatment of a carotid blowout patient thought to be at high risk for surgery or carotid occlusion. Stent placement in the common carotid artery or carotid bulb is a technical challenge because of large luminal diameter and luminal calibre discrepancy between internal carotid artery and common carotid artery. We present four patients with common carotid rupture and massive bleeding who were treated with self-expanding covered stents, among them, two cases were treated with newly designed self-expanding polytetrafluoroethylene (PTFE)-covered nitinol stents.

Topics: Aged; Alloys; Blood Vessel Prosthesis; Carotid Artery, Common; Carotid-Cavernous Sinus Fistula; Critical Illness; Equipment Design; Fatal Outcome; Head and Neck Neoplasms; Hemorrhage; Humans; Male; Middle Aged; Polytetrafluoroethylene; Radiography; Rupture, Spontaneous; Stents

To evaluate the performance of a combined hybrid radiography/magnetic resonance (MR) unit to guide portal vein (PV) puncture during human transjugular intrahepatic portosystemic shunt (TIPS) creation.. Fourteen patients undergoing TIPS creation were studied during standard clinical applications. Patients were anesthetized and then positioned in an open MR unit containing a flat-panel radiographic fluoroscopic unit. With use of a combination of fluoroscopy and MR imaging, the PV was accessed and the TIPS procedure was performed. A noncovered nitinol stent or a covered stent-graft was placed in the TIPS tract. Number of punctures required, total procedure time, fluoroscopy time, procedural success rate, complications, and ultrasonographic and clinical follow-up were recorded.. Clinical success was obtained in 13 of 14 patients. In one patient, extrahepatic puncture of the PV occurred, resulting in hemorrhage and requiring placement of a covered stent to control the bleeding. The mean number of punctures required to access the PV was 2.6 +/- 1.7, and the total procedure time was 2.5 hours +/- 0.6. Mean fluoroscopy time was 22.3 minutes +/- 5.5. Results of clinical and ultrasonographic follow-up compare favorably to previously published reports.. TIPS creation with a combination hybrid radiography/MR unit is feasible and may reduce the number of needle passes required and radiation exposure, with similar overall outcomes compared with studies reported in the literature.

Topics: Alloys; Feasibility Studies; Female; Fluoroscopy; Follow-Up Studies; Hemorrhage; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Portasystemic Shunt, Transjugular Intrahepatic; Punctures; Radiography, Interventional; Radiology, Interventional; Stents; Time Factors; Treatment Outcome; Ultrasonography, Interventional

To evaluate the long-term palliative effect of self-expanding nitinol esophageal stents in patients with malignant dysphagia.. One hundred patients with severe dysphagia secondary to malignant esophageal strictures were treated with self-expanding nitinol stents. The strictures were caused by squamous carcinoma (n = 43), adenocarcinoma (n = 28), anastomotic tumor recurrence (n = 14), and mediastinal tumor (n = 15).. One hundred six stents were successfully positioned in 100 patients. Attempts to insert a second, coaxial stent were unsuccessful in two patients; a second stent was placed incorrectly in another patient. Statistically significant (P < .001) reduction of dysphagia was noted after expansion of the stents. Complications consisted of incomplete expansion secondary to stent twisting (n = 4), stent migration (n = 4), tumor ingrowth (n = 17), tumor overgrowth (n = 3), food impaction (n = 5), fracture of stent wires (n = 2), benign strictures at stent edges (n = 2), tumor bleeding (n = 3), and esophagorespiratory fistula (n = 5). The primary patency rate was 75% (77 of 102 stents); the secondary patency rate was 94% (96 of 102 stents). The survival time (mean, 6.2 months; range, 0.1-47 months) varied with the diagnosis.. Placement of self-expanding nitinol stents is safe and has a good long-term palliative effect on dysphagia in patients with malignant esophageal strictures.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Alloys; Anastomosis, Surgical; Carcinoma, Squamous Cell; Deglutition Disorders; Equipment Design; Equipment Failure; Esophageal Fistula; Esophageal Neoplasms; Esophageal Stenosis; Evaluation Studies as Topic; Female; Follow-Up Studies; Food; Foreign-Body Migration; Hemorrhage; Humans; Longitudinal Studies; Male; Mediastinal Neoplasms; Middle Aged; Neoplasm Recurrence, Local; Palliative Care; Respiratory Tract Fistula; Stents; Surface Properties; Survival Rate