bluuebunny/crossref_metadata_2025 huggingface dataset:
Endovascular Graft Infection: Preliminary Results of an International Enquiry
Authors: Fiorani Paolo , Speziale Francesco , Calisti Annalisa , Misuraca Maria , Zaccagnini Davide , Rizzo Luigi , Giannoni Maria Fabrizia
Published: March 2015

Purpose:

To investigate the frequency of aortoiliac endovascular graft infections and seek the main factors influencing their development.

Methods:

To augment personal experience (1 case), a questionnaire was sent to 40 international centers of vascular and endovascular surgery. The literature was also reviewed to collect data on infections developing in endovascular grafts.

Results:

The survey (85% response rate) and literature review identified 62 cases of infected endovascular grafts (0.4% frequency of endograft infection). In 22 (35%) patients, the infection manifested initially with vague symptoms only, but 41 (65%) patients eventually presented with abdominal abscess, groin fistula, and septic embolization. Common bacteria, such as Staphylococcus aureus, were identified as the cause of most infections (54.5%). The majority (49, 79%) of the 62 patients were treated surgically; 11 (17.7%) patients received conservative therapy (no therapeutic data in 2 patients). Overall mortality was 27.4% (17/62), and operative mortality was 16.3% (8/49). Conservative treatment led to a mortality rate of 36.4% (4/11). The mean follow-up for all patients was 47.8 weeks. Possible factors influencing the development of an infection were secondary adjunctive procedures, immunosuppression, treatment of false aneurysms, and infected central lines.

Conclusions:

Infected endovascular grafts are an urgent problem that has been heretofore underestimated and will probably increase as follow-up lengthens. New techniques should be sought to expedite the diagnosis, and an international registry should be set up to provide validated data.
Retrograde Fenestration of Endoluminal Grafts from Target Vessels: Feasibility, Technique, and Potential Usage
Authors: McWilliams Richard G. , Fearn Shirley J. , Harris Peter L. , Hartley David , Semmens James B. , Lawrence-Brown Michael M.D.
Published: March 2015

Purpose:

To report initial experiments involving a new method for percutaneous intraprocedural stent-graft fenestration from the target vessel.

Technique:

In bench and canine models, the fabric of an implanted Zenith endograft was punctured easily using the stiff end of a coronary 0.014-inch guidewire delivered through the target vessel (e.g., renal or iliac artery). A 20-G cutting needle was passed over the coronary wire to enlarge the puncture site, followed by a cutting balloon to create a fenestration that was of sufficient size to allow deployment of a stent.

Conclusions:

In vivo endograft fenestration of a Zenith endograft is feasible. In addition to providing a percutaneous means of intentionally fenestrating a stent-graft from the artery to be perfused, the technique has potential application as a bailout maneuver after inadvertent side branch occlusion. Although the time to achieve successful fenestration in the experimental model was long, refinement may achieve performance times adequate to maintain viability of the end organ.
Chronic Aortic Dissection Complicated by Disseminated Intravascular Coagulation: Successful Treatment with Endovascular Stent-Grafting
Authors: Sakamoto Ichiro , Matsuyama Naohiro , Fukushima Aya , Hayashi Hideyuki , Nishida Akifumi , Hazama Shiro , Noguchi Manabu , Eishi Kiyoyuki , Hayashi Kuniaki
Published: March 2015

Purpose:

To report endovascular repair of a chronic aortic dissection complicated by disseminated intravascular coagulation (DIC).

Case Report:

A 61-year-old man developed DIC associated with a chronic Stanford type B aortic dissection that occurred during cardiac catheterization 12 years earlier. At the current admission, computed tomography showed a partially thrombosed false lumen extending from the aortic arch to the left common iliac artery. On angiography, entry and re-entry tears were identified at the right subclavian and left common iliac arteries, respectively. After stent-graft implantation at the entry and re-entry sites, not only was the false lumen completely thrombosed but the DIC also resolved. The patient is doing well with no complication at 16 months after treatment.

Conclusions:

Endovascular stent-grafting is an acceptable alternative to surgical repair for aortic dissection accompanied by DIC.
Chronic Platelet and Neutrophil Adhesion: A Causal Role for Neointimal Hyperplasia in In-Stent Restenosis
Authors: Tanguay Jean-François , Hammoud Talal , Geoffroy Pascale , Merhi Yahye
Published: March 2015

Purpose:

To investigate the relationship between platelets and neutrophils and the progression of neointimal hyperplasia after angioplasty versus stenting of porcine coronary arteries.

Methods:

Balloon angioplasty or implantation of a balloon-expandable stent was randomly performed in the left and right coronary arteries of 16 Yorkshire swine; the animals were euthanized 1 hour (n=6), 24 hours (n=4), or 1 month (n=6) after the interventions. The adhesion of chromium 51-labeled platelets and indium 111-labeled neutrophils was quantified (per cm2), and histological and morphometric analyses were performed.

Results:

The acute adhesion of platelets and neutrophils observed on the injured segments 1 hour after the interventions was similar between the treated groups. However, at 24 hours, stenting was associated with 2-fold more platelets and 3-fold more neutrophils (p<0.05) than was dilation, and stented arteries remained more thrombogenic at 1 month (p<0.05). Neointimal formation was more intense after stent implantation (3.80±0.77 mm, p<0.05) than after dilation (0.81±0.21 mm), and it correlated positively with the adhesion of platelets (r=0.81, p<0.002) and neutrophils (r=0.69, p<0.01).

Conclusions:

These results indicate that stent implantation is associated with a more intense acute and chronic, low-grade inflammatory response than is dilation. It appears that the chronic inflammatory response is, at least in part, platelet- and neutrophil-driven and contributes to the progression of neointimal proliferation after stenting.
Platelet Adhesion to Simulated Stented Surfaces
Authors: Robaina Samuel , Jayachandran Bhavani , He Yong , Frank Andreas , Moreno Michael R. , Schoephoerster Richard T. , Moore James E.
Published: March 2015

Purpose:

To determine if the protrusion of stent struts into the flow stream, which creates stagnation along the wall dependent on the strut spacing, has an effect on platelet adhesion.

Methods:

Three 2-dimensional stents with different strut spacings were placed in a flat-plate flow chamber. Human blood was collected and platelets were labeled with indium 111. The blood with radioactive platelets was pumped through the flow chamber for 30 minutes to produce a pulsatile wall shear stress of 10±5 dynes/cm2 (mean ± amplitude at 1 Hz). A gamma counter measured radioactivity along the surface and on the stents. Computational flow simulations provided specific data on flow separation and wall shear stress for each stent strut spacing tested (2.5, 4.0, and 7.0 times the strut height).

Results:

The presence of any stent provoked an elevation in platelet adhesion within the stented region (p<0.05). The stents with larger strut spacing had higher platelet adhesion on the substrate in the stented region (1.71±0.63 normalized platelet deposition for the 7.0 model and 2.11±1.02 for the 4.0 model) than stents with smaller strut spacing (1.37±0.68 for the 2.5 model, p<0.05). The stents themselves showed platelet adhesion levels that were 3 to 7 times higher than the substrates, with a similar dependence on stent strut spacing.

Conclusions:

Additional knowledge of the role of mechanical factors in stent restenosis will aid in designing stents that minimize intimal hyperplasia and restenosis. The results of this study demonstrate the importance of stent design-mediated blood flow patterns, with smaller strut spacings minimizing platelet adhesion per unit strut area.
Percutaneous Management of Extensive Clot Trapped in a Temporary Vena Cava Filter
Authors: Vrachliotis Thomas G. , Tachtaras Athanassios , Doundoulakis Nicholaos , Sheiman Robert G. , Papadopoulos Vassilios , Stringaris Kiriakos A.
Published: March 2015

Purpose:

To present percutaneous management of extensive clot trapped in a temporary inferior vena cava (IVC) filter.

Case Report:

A 20-year-old man with a large sacral tumor and left external iliac vein thrombosis had a wire-mounted Günther temporary filter (GTF) prophylactically placed in the infrarenal IVC prior to tumor resection. The 7-day postsurgical venogram prior to filter removal showed extensive clot trapped by the filter, as well as interval cephalic migration, with the filter tip now at the level of the renal veins. A Günther Tulip MReye (GTM) filter was deployed but not released above the renal veins to prevent clot migration during caudal withdrawal of the wire-mounted GTF. After creating enough space in the infrarenal IVC, the GTM was repositioned and fully released with its apex now below the renal veins. The GTF was then uneventfully removed. There was no clinical evidence for significant pulmonary embolism 12 months after placement.

Conclusions:

Cephalic migration of a clotted temporary IVC filter can be managed with intraprocedural protection against pulmonary embolism by first deploying a Günther Tulip filter above the renal veins, with subsequent advancement below the renal veins before temporary filter removal.
Patency Rates of Femorofemoral Bypasses Associated with Endovascular Aneurysm Repair Surpass Those Performed for Occlusive Disease
Authors: Lipsitz Evan C. , Ohki Takao , Veith Frank J. , Rhee Soo J. , Gargiulo Nicholas J. , Suggs William D. , Wain Reese A.
Published: March 2015

Purpose:

To evaluate the patency rates of femorofemoral grafts performed in conjunction with aortomonoiliac or aortomonofemoral (AMI/F) endografts.

Methods:

Over the past 8 years, 110 patients (98 men; mean age 77 ± 7 years, range 57–90) underwent aortoiliac aneurysm repair with an AMI/F endograft. Follow-up data in these patients were prospectively collected for a mean 2.3 years (range 1–68 months).

Results:

There were 2 early (<7 days) AMI/F endograft thromboses with secondary femorofemoral graft occlusion. In both patients, patency of all grafts was restored by thrombectomy plus stenting of the endograft. Three late (4, 5, and 10 months) AMI/F endograft thromboses led to femorofemoral graft failure; 2 were successfully treated, but the third patient refused further intervention. No femorofemoral bypass failed in the absence of AMI/F endograft thrombosis. There were no femorofemoral graft infections. Four-year life-table primary and secondary patency rates were 95% and 99%, respectively.

Conclusions:

Femorofemoral bypasses with AMI/F endografts for aneurysmal disease are durable procedures and have better patency than femorofemoral grafts used to treat occlusive disease. Femorofemoral bypass patency rates alone are not a disadvantage of aortomonoiliac endografts.
Improvement in Proximal Aortic Endograft Fixation: An Experimental Study Using Different Stent-Grafts in Human Cadaveric Aortas
Authors: Veerapen Reuben , Dorandeu Anne , Serre Isabelle , Berthet Jean-Phillipe , Marty-Ane Charles Henri , Mary Henri , Alric Pierre
Published: March 2015

Purpose:

To compare the proximal fixation characteristics of different types of stent-grafts (SG) and the adjunctive effect of a proximally placed Palmaz stent.

Methods:

Human cadaveric aortas were obtained at autopsy and cut into 30 aortic segments. Appropriately oversized (10% to 20%) commercial stent-grafts (Zenith, Ancure, Excluder, Talent) and 4 configurations of homemade Palmaz-based stent-grafts (polytetrafluoroethylene or polyester coverings each with no uncovered proximal edge or a 20-mm bare section of stent) were implanted 20 mm into an aortic segment and balloon dilated. Each segment was placed in an experimental apparatus to measure the dislodgment force. Bare Palmaz stents were used to reinforce the proximal fixation of the commercial stent-grafts, and the measurements were repeated. Manual anastomoses were made and their dislodgment force tested for comparison.

Results:

The median dislodgment force ranged from 6.5 N for the Excluder to 26.5 N for the Zenith (8.0 N for the Talent, 11.8 N for the Ancure, and 8.1 to 10.7 N for the various Palmaz stent-graft designs). There was no significant difference between the Zenith and the Ancure groups or between the Excluder and the Talent groups. However, the Zenith and Ancure devices required significantly higher (p = 0.0004) force (∼25%) to displace them than the other stent-grafts tested. With the Palmaz stent added to the proximal attachment site, the median dislodgment force for the different commercial endografts was significantly improved for all devices (p < 0.03): 34% for the Zenith device, 69% for the Ancure, 73% for the Talent, and 80% for the Excluder endoprosthesis.

Conclusions:

The Zenith stent-graft had the best resistance to dislodgment. An additional Palmaz stent placed at the proximal attachment site greatly improves endograft fixation regardless of the type of stent-graft. For complex aneurysm necks or for intraoperative type I endoleak management, an adjunctive Palmaz stent could be used.
AneuRx Stent-Graft Failure Four Years after TAA Exclusion
Authors: Schepens Marc A. , van den Berg Jos C. , Moll Frans L. , Dossche Karl M. , Heijmen Robin H.
Published: March 2015

Purpose:

To present a case of graft material disruption 4 years after thoracic aortic aneurysm (TAA) exclusion with the AneuRx stent-graft.

Case Report:

In 1999, a 62-year-old man underwent successful exclusion of a descending 98-mm TAA with 2 AneuRx stent-grafts. A type I distal endoleak was diagnosed 1 month later, and a distal extension cuff was placed just proximal to the celiac trunk. One year later, a new endoleak was discovered (presumed to be type II); the patient refused proposed thrombin injection to seal the leak. The diameter of the aneurysm enlarged gradually, and in 2003, he presented with a ruptured TAA and a massive left-sided hemathorax. The patient underwent urgent open surgical repair using extracorporeal circulation; the 3 stent-grafts were removed. Unfortunately, the patient died from cardiac failure 2 days later. Macroscopic examination showed several disruptions of the graft fabric and a stent fracture, which presumably explains the endoleak and rupture.

Conclusions:

This case reaffirms the necessity of long-term stent-graft surveillance.
Impact of Symptomatic Peripheral Arterial Disease on 1-Year Mortality in Patients Undergoing Percutaneous Coronary Interventions
Authors: Nikolsky Eugenia , Mehran Roxana , Mintz Gary S. , Dangas George D. , Lansky Alexandra J. , Aymong Eve D. , Negoita Manuela , Fahy Martin , Moussa Issam , Roubin Gary S. , Moses Jeffrey W. , Stone Gregg W. , Leon Martin B.
Published: March 2015

Purpose:

To determine the impact of symptomatic peripheral arterial disease (PAD) on clinical outcomes in patients treated with percutaneous coronary interventions (PCI).

Methods and Results:

Symptomatic PAD was identified in 1969 (18.9%) of 10440 consecutive patients undergoing PCI. Patients with PAD were older, more frequently female, and had smaller body surface area and more atherosclerotic risk factors, chronic renal insufficiency, and heart failure. Patients with PAD had lower rates of procedural success (94.2% versus 96.2%, p<0.0001) and higher rates of in-hospital complications, including all-cause mortality (2.1% versus 1.1%, p=0.0002), cardiac death (1.5% versus 0.7%, p=0.0009), urgent coronary artery bypass grafting (1.9% versus 1.2%, p=0.01), recurrent ischemia (5.6% versus 2.8%, p<0.0001), re-PCI to the target lesion (2.4% versus 1.1%, p<0.0001), stroke (0.6% versus 0.3%, p=0.0344), transient ischemic attack (0.4% versus 0.1%, p=0.01), femoral hematoma (10.3% versus 8.5%, p=0.01), retroperitoneal hematoma (0.8% versus 0.3%, p=0.009), limb ischemia (3.0% versus 0.7%, p<0.0001), gastrointestinal bleeding (1.9% versus 0.9%, p<0.0001), and blood transfusion (10.1% versus 5.2%, p<0.0001). At 1-year follow-up, patients with PAD had a higher mortality rate (13.6% versus 5.2%, p<0.0001), a higher rate of myocardial infarction (8.3% versus 6.5%, p=0.008), and also more target lesion (21.2% versus 19.8%, p=0.02) or target vessel revascularization (24.6% versus 21.2%, p=0.002). By multivariate analysis, PAD was an independent predictor of 1-year mortality (odds ratio 1.71, 95% confidence interval 1.42 to 2.07, p<0.0001).

Conclusions:

Nearly a fifth of patients undergoing PCI have symptomatic PAD. The presence of PAD is associated with lower rates of procedural success, higher rates of in-hospital and 1-year adverse events, and is independently associated with increased 1-year mortality.
Endografting of the Aortic Arch
Authors: Ishimaru Shin
Published: March 2015

In recent years, endovascular repair with stent-grafts has made great advances as a minimally invasive alternative to conventional open surgery in the treatment of aortic aneurysm and dissection. Although many commercial endograft systems are now used worldwide for the treatment of these pathologies in the abdominal aorta, only a few dedicated stent-grafts have been developed for use in the thoracic aorta. However, these second-generation commercial endografts have almost identical specifications and performance profiles in terms of structure, function, and delivery mechanism as stent-graft systems employed in the abdominal aorta. Thus, endografts have been used in the thoracic aorta with little consideration to the morphological and hemodynamic characteristics specific to the aortic arch and the deployment techniques needed to navigate this curved region of the thoracic aorta. This review will survey the literature on aortic arch stent-graft repair and identify key elements critical to the successful design of an endograft to treat lesions in the aortic arch.
Endograft Technology: Highlights of the past 10 Years
Authors: Fogarty Thomas J. , Arko Frank R. , Zarins Christopher K.
Published: March 2015

The past decade has seen the evolution of an exciting technology that has changed forever the treatment of aortic aneurysmal disease. From rather crude homemade stent-grafts constructed in the surgical suite to elegant commercially manufactured devices in a variety of configurations and sizes, the aortic endograft has experienced a meteoric rise in popularity to become a beneficial, minimally invasive therapy that can obviate the risk of rupture and death. There are now 3 approved endovascular devices on the market for infrarenal abdominal aortic aneurysm repair, and it is likely that additional and improved devices will become available in the future. This review revisits the developmental history of the aortic endograft, noting the ongoing refinements that have arisen from our experiences with the growing population of stent-graft patients. Although research continues to search for solutions to the problems of endoleak and migration, long-term results even with the earlier second and third-generation devices are better than has been achieved with open surgical repair.
Intravascular Stents in the Last and the Next 10 Years
Authors: Palmaz Julio C.
Published: March 2015

The first balloon-expandable coronary stent was approved “for the prevention of restenosis” in 1994, the same year that the Journal of Endovascular Therapy was inaugurated. Since then, the development of the stent has paralleled the evolution of endovascular intervention as a new specialty. Innovators have pushed to explore new and varied stent applications outside the coronary arteries. Carotid stenting, transjugular intrahepatic portocaval shunts, and covered stents are a few of these new applications that have now become commonplace. Dozens of stent designs and several new materials have been tested to solve the problem of in-stent restenosis, but it is the drug-eluting stent (DES) that has emerged as the most promising, at least in the coronary arteries. However, the benefits of DES technology are not likely to be effective in the more pervasive forms of in-stent restenosis, such as encountered in the femoropopliteal segment.

In the future, technologies aimed at stimulating rather than inhibiting tissue response to an implant may be part of the next wave of developments, as we take aim against the poor and/or slow tissue incorporation that manifests as leaks and dislodgement. In the superficial femoral artery, for example, mechanical stresses that cause fractures and dislocations may be addressed by using a very flexible endovascular device with a tissue-friendly inner surface that promotes rapid stent endothelialization to counter the biological effects of motion and microtrauma. The rapidly developing fields of nanotechnology, microelectronics, and advanced materials technology will enable the surface engineer to design molecular-specific surfaces for a new generation of vascular devices. Interactive implantable or injectable microdevices aimed at providing specific information upon demand from an external source will revolutionize disease prevention, as emphasis shifts toward monitoring cardiovascular risk exposure. There is no doubt that during the next 10 years, we will witness impressive technological progress in the field of cardiovascular implantable devices.
Renal Function after Endovascular Aortic Aneurysm Repair: A Single-Center Experience with Transrenal versus Infrarenal Fixation
Authors: Waasdorp Evert , Hullenaar Casper van't , van Herwaarden Joost , Kelder Hans , van de Pavoordt Eric , Overtoom Tim , Moll Frans , de Vries Jean-Paul
Published: March 2015

Purpose:

To describe the short-term consequences of endovascular aortic aneurysm repair (EVAR) on renal function after infrarenal (IR) versus transrenal (TR) stent-graft fixation.

Methods:

Between December 1996 and January 2006, 369 consecutive patients were treated with EVAR. All patients had an AneuRx or a Talent stent-graft implanted using IR (AneuRx) or transrenal (Talent) fixation. Post-EVAR, a standardized follow-up scheme included computed tomography (CT) scanning and serum creatinine measurements at 2 days, 3 months, and 12 months. Postoperative renal dysfunction was defined as a >20% decrease in serum creatinine clearance compared to baseline, the presence of new-onset dialysis, or both. Of the 369 patients, 309 (291 men; mean age 71±7 years, range 63–82) had complete 1-year follow-up and were included in this study. An IR stent-graft was placed in 190 patients, and a TR stent-graft was placed in the remaining 119 patients.

Results:

At discharge, renal dysfunction occurred in 3.7% of the patients in the IR group versus 5.9% in the TR group (p=NS) and rose significantly to 13.7% in the IR group (p=0.001) and 15.1% in the TR group (p=0.02) at the 1-year follow-up. However, no significant difference was noted between the IR and TR groups at either time point. At the 1-year follow-up, at least 50% of renal dysfunction was caused by obstructions of (accessory) renal arteries and renal infarctions. During the follow-up interval, 3 (0.97%) of 309 patients underwent new-onset dialysis.

Conclusion:

Both infrarenal and transrenal fixation techniques in EVAR will lead to a significant rise in renal dysfunction during the first year. A few patients with dysfunction will require dialysis.
Double Tube Stent-Grafts for Infrarenal Aortic Aneurysm: A New Concept
Authors: Ruppert Volker , Erz Kerstin , Bürklein Dominik , Treitl Marcus , Steckmeier Bernd , Stelter Wolf , Umscheid Thomas
Published: March 2015

Purpose:

To present the concept of double tube stent-grafts and examine the indications for and results achieved with these devices.

Methods:

From January 1, 2000, to December 31, 2005, 759 patients who underwent endovascular repair of infrarenal aortic aneurysms at 2 centers. Of these, 45 (5.9%) patients received a double tube stent-graft; complete operative and follow-up data were available for retrospective analysis in 41 patients (33 men; mean age 73.1±8.9 years). Diameters measured before stent-graft implantation and at follow-up (12, 24, 36, and 48 months) with clinical examination, 2-phase computed tomographic angiography, duplex sonography, and biplanar abdominal radiography were tested for significant changes using ANOVA with the Bonferroni-Dunn correction. Late outcomes (clinical success and endoleak) were analyzed by the Kaplan-Meier method.

Results:

The postoperative complication rate was 12.2%, with 2.4% systemic complications (1 patient with angina pectoris); the early mortality rate was 0%. Mean follow-up was 21.9±12.8 months (range 12–61) for the 41 patients. Four (9.8%) patients died during follow-up of cardiac causes (n=2), lung cancer (n=1), and bowel ischemia (n=1). Four (9.8%) endoleaks were observed during follow-up: 1 distal type I, 2 type II, and 1 type III. Maximum aneurysm diameters shrank from 52.0±9.5 mm preoperatively to 44.0±10.8 mm (p<0.0001) postoperatively at the latest available follow-up.

Conclusion:

Our study supports the use of this double tube technique for repair of appropriate saccular infrarenal aortic aneurysms. The double tube stent-graft method appears safe in terms of endoleaks and migration, so we recommend that it be considered an option of endovascular aortic aneurysm therapy.
In Vivo Antegrade Fenestration of Abdominal Aortic Stent-Grafts
Authors: Tse Leonard W. H. , Bui Bao T. , Lerouge Sophie , Salazkin Igor , Therasse Eric , Benko Andrew , Héon Hélène , Oliva Vincent L. , Soulez Gilles
Published: March 2015

Purpose:

To examine in a canine model the feasibility of antegrade fenestration of abdominal aortic stent-grafts to preserve the patency of the renal arteries.

Methods:

Two large dogs underwent antegrade fenestration of stent-grafts in the perirenal aorta. Before fenestration, bare stents were inserted in both renal arteries as fluoroscopic landmarks. A 12-mm iliac extension served as the canine aortic endograft. The first procedure was done under ultrasound and fluoroscopic guidance, using an intravascular ultrasound (IVUS) probe inserted in the vena cava and a Pioneer IVUS catheter. The second was performed exclusively under fluoroscopic guidance with a Brockenbrough needle. Angiograms and duplex ultrasound were planned for 1 month, after which the dogs would be sacrificed for autopsy. The explanted endograft was subjected to biomaterials analysis, with a focus on fabric tear.

Results:

Perforation of the aortic graft and catheterization of the renal arteries with a floppy guidewire were possible in both animals. In dog 1, aortic graft dilation and subsequent fenestration were not possible, and the experiment was terminated. However, the procedure was successful in both renal arteries of dog 2. At 1-month follow-up in this dog, both renal arteries were patent. Stent fractures were observed bilaterally. There was no extension of the damage to the fabric beyond the area of fenestration.

Conclusion:

In vivo antegrade fenestration of aortic endografts is technically feasible. However, improvements in technique, instrumentation, and materials are required to make it a reliable and reproducible way of allowing stent-graft vascularization of aortic side branches.
Differential Effects of Carotid Artery Stenting versus Carotid Endarterectomy on External Carotid Artery Patency
Authors: Woo Edward Y. , Karmacharya Jagajan , Velazquez Omaida C. , Carpenter Jeffrey P. , Skelly Christopher L. , Fairman Ronald M.
Published: March 2015

Purpose:

To determine the effect of stent coverage of the external carotid artery (ECA) after carotid artery stenting (CAS) compared to eversion endarterectomy of the ECA after carotid endarterectomy (CEA).

Methods:

The records of 101 CAS and 165 CEA procedures performed over 2 years were reviewed. Duplex velocities and history and physical examinations were taken prior to the procedure, at 1 month, and at 6-month intervals subsequently. CAS was performed by extending the stent across the internal carotid artery (ICA) lesion into the common carotid artery (CCA) thereby covering the ECA. CEA was performed with eversion endarterectomy of the ECA.

Results:

The mean peak systolic velocities (PSV) in the ICA pre-CAS and pre-CEA were 361 and 352 cm/s, respectively. In terms of CAS, there was a significant increase in ECA velocities versus baseline at 12 (p=0.009), 18 (p=0.00001), and 24 (p=0.005) months. In the CEA group, there was a significant decrease in ECA velocities versus baseline at 1 (p=0.01) and 6 (p=0.004) months. There were 2 occluded ECAs in follow-up in the CAS group and none in the CEA group. No significant differences were noted when comparing preprocedural ICA or ECA velocities. However, at the 1-, 6-, and 12-month intervals, the ECA velocities in the CAS group were significantly higher than in the CEA group (p=0.03, p=0.001, and p=0.0004, respectively). There were no neurological symptoms in any patients during the study period.

Conclusion:

Although progressive stenosis of the ECA is noted during CAS, the ECA usually does not occlude. Furthermore, there are no associated neurological symptoms. Thus, apprehension for progressive ECA occlusion should not be a contraindication to CAS. In addition, concern for ECA coverage should not deter stent extension from the ICA to the CCA during CAS.
Tandem Balloon Protection during Emergency Carotid Artery Stenting of a Stenotic ICA Lesion with Intraluminal Thrombus
Authors: Imai Keisuke , Makino Masahiro , Niwa Fumitoshi , Takegami Tetsuro , Koike Hironori , Azuma Yumiko , Oshima Fumiko , Oda Kenichiro , Kakita Kiyohito
Published: March 2015

Purpose:

To report a technique for emergency CAS of a stenotic internal carotid artery (ICA) lesion with an intraluminal thrombus, which predisposes to distal thromboembolism and could aggravate pre-existing neurological symptoms.

Case Report:

A 77-year-old man with fluctuating stroke underwent successful emergency CAS for an ICA stenosis with intraluminal thrombus using a tandem balloon protection technique featuring proximal balloon blockade and a PercuSurge GuardWire system for distal protection.

Conclusion:

This experience suggests that emergency CAS with tandem balloon protection is a potential treatment for a stenotic lesion with an intraluminal thrombus in patients with fluctuating stroke.
Ultrasound-Enhanced Thrombolysis
Authors: Motarjeme Amir
Published: March 2015

Purpose:

To report a single-center clinical experience with ultrasound-enhanced thrombolysis in the treatment of both arterial and venous thromboses.

Methods:

From January 2005 to June 2006, 33 patients (23 men; age range 39–90 years) with 36 occlusions were treated using ultrasound-enhanced thrombolytic therapy for acute and chronic arterial and venous occlusions. After diagnostic angiography, the occlusions were crossed with an appropriately sized Lysus infusion catheter for infusion of urokinase (80,000–120,000 IU/h).

Results:

Technical success and complete lysis was achieved in 96% of the arterial and 83% of the venous occlusions. Two patients with chronic occlusions (one superficial femoral artery and one iliac vein) were refractory to lytic therapy. Average time for complete lysis was 16.4 hours (range 3–25) for arterial occlusions and 21.2 hours (range 6–43) in patients with deep vein thrombosis.

Conclusion:

Successful clot lysis can be achieved with a high rate of success in a shorter time than conventional thrombolysis using ultrasound-enhanced thrombolysis in both acute and chronic arterial and venous thromboses.
TCD Evaluation before and after Stenting in Patients with Severe Primary Carotid Artery Stenosis versus Restenosis
Authors: Telman Gregory , Kouperberg Efim , Sprecher Elliot , Gruberg Luis , Beyar Rafael , Yarnitsky David
Published: March 2015

Purpose:

To evaluate cerebral hemodynamics before and after carotid angioplasty and stenting (CAS) using transcranial Doppler (TCD).

Methods:

Sixty-eight patients (52 men; mean age 69±9.5 years) with severe carotid stenosis (83.4%±10.2%) were examined by TCD before and 2 months after CAS. Thirty-two (47%) patients had primary carotid stenosis and 36 (53%) had restenosis after carotid endarterectomy (CEA). A broad TCD protocol was employed to estimate cerebral hemodynamics, including assessment of velocities (V) and asymmetry of cerebral blood flow velocity (CBFV) in the middle cerebral artery, (MCA) anterior cerebral artery (ACA), and basilar artery (BA); the pulsatility indexes; and flow acceleration.

Results:

Ipsilateral MCA mean velocities before stenting were 46.3±12.6 cm/s in the primary stenosis group and 47.1±12.3 cm/s in restenosis group; after stenting, the velocities were 53.8±12.1 and 52.7±9.6 cm/s, respectively (p<0.005 for both groups). MCA asymmetry by Vmean before CAS was higher in the primary stenosis group (27.6%±2.4% versus 19.8%±2.3%, p<0.05). After stenting, this index was significantly lower in both groups: 16.4%±2.4% and 12.3%±2.3%, respectively (p<0.0001 for each group). All other TCD parameters improved significantly in both groups after CAS as well (p<0.05), showing the strong hemodynamic effect of this procedure.

Conclusion:

CAS effectively improves cerebral hemodynamics in patients with severe primary and restenosis of the internal carotid artery.
Multicenter Safety and Efficacy Analysis of Assisted Closure after Antegrade Arterial Punctures Using the StarClose Device
Authors: Williams Robin Edward Thomas , Angel Claude Y. , Bourkaib Ryad , Brenot Philippe , Commeau Philippe , Fisher Robert Kendall , Jackson Ralph , Kay Caroline Helen , Le Dref Olivier , Riou Jean-Yves , Rose John , MacDonald Sumaira
Published: March 2015

Purpose:

To evaluate the safety and efficacy of the StarClose device for closure of antegrade punctures following infrainguinal endovascular interventions.

Methods:

A retrospective review was conducted of 221 consecutive patients treated with the StarClose device in a 12-month period at 5 centers (4 French and 1 British). Of these, 107 patients (69 men; median age 75 years, range 44–93) were from the UK cohort (111 closures), and 94 patients (75 men; median age 67 years, range 32–95) were from the French cohort (111 closures). Technical success, complication rates, demographic data, medical history, and procedural details were gathered for all patients. Residual bleeding and the requirement for additional manual compression were recorded when the device failed. Clinical evaluation was performed at discharge; color-coded duplex ultrasonography was done in a subset of French patients.

Results:

The overall technical success rate was 94.6% (210/222; 95% CI 3.1%–9.2%). The results were similar in the 2 cohorts: 95.5% (106/111; 95% CI 1.9%–10.1%) in the UK and 93.7% (104/111; 95% CI 3.1%–12.4%) in France. The 12 failures (5 UK and 7 France) were due to several mechanisms: device failure (n=5), obesity (n=1), groin scarring (n=2), and unexplained (n=4). In 2 failed cases, open surgical closure of the arteriotomy was performed because pressure hemostasis failed. Two pseudoaneurysms were observed: one after immediate failure was successfully treated by prolonged pressure; the other, after apparent success of the device, required surgical therapy. The incidence of serious vascular complication was 1.8% (4/222; 95% CI 0.7%–4.5%); 2 patients from each cohort.

Conclusion:

The StarClose device safely and effectively closes antegrade punctures after infrainguinal endovascular intervention, even in patients who would be considered to be at high risk for puncture-site bleeding. However, a randomized trial would be required to support any definitive recommendations.
Targeted Renal Therapy and Contrast-Induced Nephropathy during Endovascular Abdominal Aortic Aneurysm Repair: Results of a Feasibility Pilot Trial
Authors: Allie David E. , Lirtzman Mitchell D. , Wyatt Charles H. , Keller V. Antoine , Mitran Elena V. , Hebert Chris J. , Patlola Raghotham , Veerina Kalyan K. , Walker Craig M.
Published: March 2015

Purpose:

To evaluate the feasibility of targeted renal therapy (TRT) to decrease the rate of contrast-induced nephropathy (CIN) during endovascular aortic aneurysm repair (EVAR) in patients at risk for CIN.

Methods:

A prospective nonrandomized analysis of TRT was performed in 10 high-risk patients (8 men; median age 66.5 years, range 56–80) with pre-existing renal insufficiency. TRT involved high-dose intrarenal artery infusions of fenoldopam (FEN), a short acting selective dopamine-1 agonist and renal arteriolar vasodilator, delivered percutaneously via a left brachial access using the 5-F Benephit PV Infusion System during EVAR.

Results:

There were no device-related complications. TRT infusion duration ranged from 3.5 to 6.0 hours (median 4.5). Median contrast dosage was 120 mL (range 50–200). At 24 and 72 hours after EVAR, creatinine clearance (CrCl) had improved in 7 (70%) patients, remained unchanged in 2 (20%), and declined >25% in 1 (10%); the latter returned to baseline on day 5. At 30 days, 7 (70%) patients had improved CrCl and 3 (30%) remained unchanged.

Conclusion:

TRT is feasible during EVAR in high-risk patients. Further investigation is warranted to determine the safety and efficacy of TRT in preserving renal function during EVAR.
Changes in Coronary Flow Reserve following Stent Implantation in the Swine Descending Thoracic Aorta
Authors: Zacharoulis Achilles A. , Arapi Sophia M. , Lazaros George A. , Karavidas Apostolos I. , Zacharoulis Apostolos A.
Published: March 2015

Purpose:

To evaluate coronary flow reserve (CFR) changes following stent implantation in the descending thoracic aorta (DTA) of a porcine model.

Methods:

Six pigs (3 males; 40 to 44 kg) were anesthetized and kept on mechanical ventilation. A 6-F guiding right Judkins catheter was advanced under fluoroscopy to the right coronary artery, and a pressure wire with a temperature sensor was placed within the vessel lumen at a distance of 4 cm from the ostium. CFR was estimated by the thermodilution method before and after maximal coronary vasodilation with 20 mg of intracoronary papaverine. Aortography was also performed to measure aortic diameter. Subsequently, a self-expanding vascular stent was deployed into the DTA just below the left subclavian artery (LSA), and CFR was measured again. All animals were maintained for 3 weeks; at the end of this period, a further CFR was calculated using the same procedure.

Results:

The mean aortic diameter below the LSA was 12.15±0.15 mm. Following stent deployment, the mean aortic diameter measured at the stented segment was 12.58±0.11 (p=0.001 versus baseline). The mean CFR value was 4.7062.00 before stent implantation, 2.6860.86 immediately after, and 4.0561.15 at 3 weeks after stenting. Accordingly, CFR values were significantly depressed immediately after stent placement compared with baseline (p=0.027). However, CFR values obtained 3 weeks following stent deployment were similar to the initial values (p=0.59).

Conclusion:

Stent deployment in the normal swine DTA produces a significant immediate decrease in CFR, which is attenuated 3 weeks later. The clinical impact of CFR changes following DTA endografting remain to be elucidated.
Risk Factors for Developing Postprocedural Microemboli following Carotid Interventions
Authors: Tedesco Maureen M. , Coogan Sheila M. , Dalman Ronald L. , Haukoos Jason S. , Lane Barton , Loh Christopher , Penkar Tejus S. , Lee Jason T.
Published: March 2015

Purpose:

To determine risk factors predictive of microemboli found on diffusion-weighted magnetic resonance imaging (DW-MRI) following carotid angioplasty and stenting (CAS) with distal protection and carotid endarterectomy (CEA).

Methods:

A retrospective review was conducted of all carotid interventions at a single institution between 2004 and 2006. In that time frame, 64 carotid interventions (34 CAS, 30 CEA) were performed in 63 male patients (mean age 69.5 years, range 52 to 91) with DW-MRI scans available for review. Patient characteristics, including age, gender, smoking history, diabetes mellitus, hypertension, hyperlipidemia, obesity (body mass index >30), coronary artery disease (CAD), chronic obstructive pulmonary disease, peripheral vascular disease, and atrial fibrillation, were documented. For the CAS patients, anatomical and procedural characteristics, including fluoroscopy time, contrast volume, performance of an arch angiogram, and lesion anatomy, were recorded. Bivariate analyses were performed to determine which parameters were associated with the occurrence of acute postprocedural microemboli found on DW-MRI by 2 blinded neuroradiologists.

Results:

Twenty-four (71%) of the 34 CAS patients and 1 (3%) of the 30 CEA patients demonstrated new cerebral microemboli postoperatively. In the bivariate analyses of all patient, anatomical, and procedural characteristics, only a history of CAD was associated with an increased risk of microemboli; 20 (80%) of the 25 patients who had postprocedure microemboli had CAD compared to 18 (46%) of 39 patients without microemboli (p=0.007). Twenty (53%) of the 38 (59%) patients with CAD developed microemboli compared to 5 (19%) of the 26 patients without CAD (p=0.007). All other patient, procedural, and anatomical characteristics were not found to be independent risk factors predictive of postprocedure microemboli.

Conclusion:

CAS with distal protection carries a significantly greater risk for developing new microemboli compared to CEA. Of all the risk factors analyzed, only a history of CAD emerged as an independent risk factor for the development of microemboli following carotid intervention. This finding may influence the decision to perform CAS in patients deemed high risk solely due to the presence of CAD.
Increased Anterior Abdominal Aortic Wall Motion: Possible Role in Aneurysm Pathogenesis and Design of Endovascular Devices
Authors: Goergen Craig J. , Johnson Bonnie L. , Greve Joan M. , Taylor Charles A. , Zarins Christopher K.
Published: March 2015

Purpose:

To determine whether variations in aortic wall motion exist in mammalian species other than humans and to consider the potential implications of such variations.

Methods:

M-mode ultrasound was used to measure abdominal aortic wall motion in 4 animal species [mice (n=10), rats (n=8), rabbits (n=7), and pigs (n=5)], and humans (n=6). Anterior wall displacement, posterior wall displacement, and diastolic diameter were measured. The ratio of displacement to diameter and cyclic strain were calculated.

Results:

Body mass varied from 24.1±2.4 g (mouse) to 61.8±13.4 kg (human); aortic diameter varied from 0.53±0.07 mm (mouse) to 1.2±1 mm (human). Anterior wall displacement was 2.5 to 4.0 times greater than posterior among the species studied. The ratios of wall displacement to diastolic diameter were similar for the anterior (range 9.40%–11.80%) and posterior (range 2.49%–3.91%) walls among species. The ratio of anterior to posterior displacement (range 2.47–4.03) and aortic wall circumferential cyclic strain (range 12.1%–15.7%) were also similar. An allometric scaling exponent was experimentally derived relating anterior wall (0.377±0.032, R2=0.94) and posterior wall (0.378±0.037, R2=0.93) displacement to body mass.

Conclusion:

Abdominal aortic wall dynamics are similar in animals and humans regardless of aortic size, with more anterior than posterior wall motion. Wall displacement increases linearly with diameter, but allometrically with body mass. These data suggest increased dynamic strain of the anterior wall. Increased strain, corresponding to increased elastin fatigue, may help explain why human abdominal aortic aneurysms initially develop anteriorly. Aortic wall motion should be considered when developing endovascular devices, since asymmetric motion may affect device migration, fixation, and sealing.
Endovascular Rescue of a Fused Monorail Balloon and Cerebral Protection Device
Authors: Campbell John E. , Bates Mark C. , Elmore Michael
Published: March 2015

Purpose:

To present a case of successful endovascular retrieval of a monorail predilation balloon fused to an embolic protection device (EPD) in the distal internal carotid artery (ICA) of a high-risk symptomatic patient.

Case Report:

A 60-year-old man with documented systemic atherosclerotic disease had a severe (>70%) restenosis in the left ICA 3 years after endarterectomy. He was scheduled for carotid artery stenting (CAS) with cerebral protection; however, he developed unstable angina and was transferred to our facility, where the admitting team decided that staged CAS followed by coronary bypass grafting would be the best option. During the CAS procedure, a 6-mm AccuNet filter was passed across the lesion via a 6-F carotid sheath and deployed in the distal ICA without incident. However, the 4-×20-mm predilation monorail balloon was then advanced without visualizing the markers, resulting in inadvertent aggressive interaction that trapped the balloon's tip in the filter. Several maneuvers to separate the devices were unsuccessful. Finally, the filter/balloon combination was moved gently retrograde until the balloon was straddling the subtotal ICA lesion. The lesion was dilated to 4 mm with the balloon, and the sheath was gently advanced across the lesion as the balloon was deflated. Angiography excluded interval occlusion of the filter from the embolic debris during the aforementioned aggressive maneuvers and documented antegrade flow. The filter was slowly withdrawn into the 6-F sheath with simultaneous aspiration. A second 6-mm filter was deployed, and the procedure was completed satisfactorily. The patient did well, with no neurological sequelae.

Conclusion:

EPDs are an essential in carotid artery stenting and, keeping in mind the potential risks associated with their use, will help the operator avoid complications such as this one.
Improving Endograft Stability by Accommodation onto the Aortic Bifurcation
Authors: Perdikides Theodossios P. , Avgerinos Efthimios D. , Lagios Konstantinos , Ziegler Peter , Stelter Wolf
Published: March 2015

Purpose:

To report the technique for deploying a 3-part endovascular graft onto the native aortic bifurcation for greater stent-graft stability.

Technique:

The Zenith Composite Endovascular Graft is a 3-part system consisting of a proximal tubular body with an uncovered Gianturco Z stent, a distal bifurcated body, and a contralateral leg. Proximally, 8-mm flexible interstent gaps facilitate precise infrarenal aortic placement, even in angulated necks. Technically, the bifurcated part is deployed first and pulled down to the aortic bifurcation, while the tubular main body and contralateral leg deployment follow. Using this technique to accommodate the graft onto the natural aortic bifurcation, distal stability can be enhanced and graft migration minimized.

Conclusion:

The Composite configuration can be an alternative to ensure a higher security index in difficult anatomies. It may be beneficial in patients with short (10–15 mm), angulated (>60°), or conical necks and deserves investigation in these patient populations.