Bower, Thomas C.

Objective: A significant cohort of patients who have undergone carotid artery stenting (CAS) will have in-stent restenosis (ISR). The optimal management of symptomatic or severe ISR remains poorly defined. The purpose of this study was to describe the indications, treatment, and mid- to long-term outcomes of patients undergoing CAS explantation for ISR. Methods: All patients undergoing internal carotid artery stent explantation with carotid artery reconstruction at Mayo Clinic Rochester, Dartmouth-Hitchcock Medical Center, and Beth-Israel Deaconess Medical Center from 2003 to 2013 were retrospectively reviewed. Isolated common carotid artery stents were excluded. Demographics, comorbidities, indications for explantation, operative details, and perioperative and postoperative outcomes were reviewed. Results: Over the study interval, a total of 971 patients underwent carotid stenting across the 3 centers. Of these, 8 patients ultimately underwent CAS explantation with carotid artery reconstruction. Mean age was 69 years and 5 patients were male. Index stent placement was for symptomatic stenosis in 4 patients, asymptomatic restenosis after endarterectomy in 2 patients, asymptomatic high lesion in 1 patient, and asymptomatic critical stenosis in 1 patient. Indications for explantation were symptomatic ISR in 4 patients and asymptomatic severe ISR in 4 patients. Method of repair was stent explantation and patch angioplasty in 5 and en bloc carotid resection with bypass in 3 patients. There were no perioperative neurologic events or cranial nerve injuries. At a mean follow-up of 38.7 months, there were 2 late disabling ipsilateral strokes (14.4 months and 19.1 months). Conclusion: A significant cohort of patients who have undergone CAS will have ISR. Although excellent perioperative results after surgical explantation can be obtained, this patient subgroup remains at risk for late neurologic events. Appropriate patient selection and diligent long-term follow-up are mandated to obtain optimal outcomes.

FiberNet® is a second generation non-conventional embolization protection device (EPD) that purports to offer several advantages: ability to capture debris as small as 40 μm, more flexibility with placement and positioning in curved segments requiring a small landing zone, ability to conform to asymmetric vessels, and improved deliverability. The design features a low profile with large surface area to capture debris. Legitimate concerns include inducement of obstruction or low flow with debris capture and requirements in the IFU to aspirate during re-capture and device removal. Our goal was to compare the results of carotid artery stenting (CAS) using FiberNet® against a multi-center experience of CAS using other filter devices to identify any differences in technical success or event rates. FiberNet® (n=25) results were compared to all CAS cases performed at the Mayo Clinic in Rochester, MN, St Mary's/Duluth Clinic in MN, and North Central Heart Institute in Sioux Falls, SD (n=250) from March 2001 to December 2008. Chi-square or means were used to compare variables, as appropriate. Bivariate logistic regression was used to identify possible correlates of adverse outcome. Statistical significance was set at < 0.05. FiberNet® patients were more likely to be older (78.1+5.4 vs 73.6+9.4, p=0.019), female (48% vs 29%, p=0.047), and have peripheral vascular disease (84.0% vs 37.2%, p=0.025), and less likely to have diabetes (8.0% vs 29.8%, p=0.012) than patients in the comparison group. FiberNet® patients had more lesion calcification (40.0% vs 18.9%, p=0.014) and increased number of type 2 and 3 arches (44.2% vs 73.9%, p=0.006). Procedural success rate was 100% in both groups. None of the FiberNet® patients showed evidence of stagnant flow. The thirty-day outcome for TIA, CVA, or death was 4% in FiberNet® versus 4.8% in the comparison group (p NS). None of the independent variables – age gender, serum creatinine, arch complexity, lesion length, lesion calcium, lesion thrombus, PVD, diabetes, contralateral carotid occlusion, or ipsilateral carotid endarterectomy – predicted adverse events. Although FiberNet® patients had more lesion calcium and more challenging arch anatomy, procedural success and adverse events were comparable between groups. The advantages of FiberNet® can be applied to CAS with good technical results and may be a promising EPD for certain high-risk situations.

Objective To evaluate the clinical and radiographic predictors of the need for partial or circumferential resection of the inferior vena cava ( IVC ) requiring complex vascular reconstruction during venous tumour thrombectomy for renal cell carcinoma ( RCC ). Patients and Methods Data were collected on 172 patients with RCC and IVC (levels I– IV ) venous tumour thrombus who underwent radical nephrectomy with tumour thrombectomy at the Mayo Clinic between 2000 and 2010. Preoperative imaging was re‐reviewed by one of two radiologists blinded to details of the patient's surgical procedure. Univariable and multivariable associations of clinical and radiographic features with IVC resection were evaluated by logistic regression. A secondary analysis was used to assess the ability of the model to predict histological invasion of the IVC by the tumour thrombus. Results Of the 172 patients, 38 (22%) underwent IVC resection procedures during nephrectomy. Optimum radiographic thresholds were determined to predict the need for IVC resection based on preoperative imaging included a renal vein diameter at the renal vein ostium ( RV o) of 15.5 mm, maximum anterior–posterior ( AP ) diameter of the IVC of 34.0 mm and AP and coronal diameters of the IVC at the RV o of 24 and 19 mm, respectively. On multivariable analysis, the presence of a right‐sided tumour (odds ratio 3.3; P = 0.017), an AP diameter of the IVC at the RV o of ≥24.0 mm (odds ratio 4.4; P = 0.017), and radiographic identification of complete occlusion of the IVC at the RV o (odds ratio 4.9; P < 0.001) were associated with a significantly increased risk of IVC resection. The c‐index for the model was 0.81. Conclusions We present a multivariable model of the radiographic features associated with the need for IVC resection during tumour thrombectomy. Pending external validation, this model may be used for preoperative planning, patient counselling and planned involvement of vascular surgical colleagues in anticipation of the need for complex vascular repair.

Embolic protection devices are occasionally employed during endovascular interventions to prevent complications caused by embolic debris. However, these devices have imperfect efficacy, confer risk of endovascular trauma, and are expensive. We report a patient with giant cell arteritis and symptomatic axillary artery stenosis, with a perceived elevated risk of distal embolization during endovascular intervention. We describe a straightforward embolic protection technique of brachial pressure cuff inflation during endovascular intervention and aspiration of displaced thrombotic material from the static column of blood. This novel, effective, and cost-free technique could also be employed in other vascular beds during endovascular intervention.

Endovascular reconstruction has become the standard treatment of chronic obstruction of large veins. Stenting is done with increasing frequency to treat iliac venous obstructions, with or without associated inferior vena caval or femoral vein occlusions. Open reconstruction with venous bypass is performed today in patients who fail attempts at venous stenting or who are not candidates for endovascular reconstructions. Patients with primary or secondary malignancies invading the vena cava undergo open caval reconstruction at the time of tumour excision. Open venous reconstructions are still preferred in patients with large vein injuries due to blunt or penetrating trauma or in those who suffer iatrogenic venous injuries. Hybrid reconstruction can be performed with endophlebectomy of the common femoral or femoral veins combined with iliofemoral stenting.

Purpose: To review the outcomes of retrograde supra-aortic vessel stent (RSAS) placement combined with open carotid or subclavian artery revascularization. Methods: Retrospective review of all consecutive patients between 1995 and 2010, excluding transfemoral procedures or isolated retrograde stent placement. Results: There were 11 patients (9 females, mean age 65 years). Open revascularization included carotid endarterectomy in 6 patients, carotid-subclavian bypass in 3, and carotid-carotid bypass in 2 patients. There were no operative deaths or neurological events. All symptomatic patients improved. Over a mean follow-up of 24 months, One patient developed common carotid artery (CCA) in-stent dissection and symptomatic restenosis treated with subclavian-carotid bypass. Another 3 patients had asymptomatic restenosis of the carotid bifurcation but required no intervention. Conclusions: Retrograde stenting of the common carotid or innominate artery is a safe and effective method to provide inflow in selected patients with severe supra-aortic vessel disease who require concomitant open carotid or subclavian artery reconstructions.

Objective: Endoleaks are critical complications of endovascular abdominal aortic aneurysm repair (EVAR). This study sought to determine the frequency and nature of intraoperative endoleaks and their impact on postoperative endoleak-related events. Methods: A retrospective chart review was performed of all patients who underwent EVAR at our institution. The impact of intraoperative endoleaks on postoperative endoleak rates and endoleak-related reintervention rates were assessed. Results: From December 18, 1996, to May 21, 2003, 241 patients underwent EVAR. An endoleak was observed during 126 (52.3%) procedures. Type I endoleaks were observed in 63 (26.1%) cases: 35 proximal and 31 distal endoleaks (3 cases at both attachments). Angioplasty, additional cuff placement, or stenting corrected 59 (89.4%) of these endoleaks. A total of 71 type II intraoperative endoleaks (29.5%) and 8 type IV endoleaks (3.3%) were observed without any attempted corrective maneuvers. Ten type III endoleaks (4.2%) occurred but all resolved with angioplasty or additional cuff placement. In all, 86 (35.7%) endoleaks persisted on completion angiogram. Patients with a type I or type II intraoperative endoleak were more likely to have an endoleak at 1.5 years (31.4% vs. 21.6%, P = .018). Reinterventions were required more often after an intraoperative type I endoleak (10% vs. 4%, P = .003). Patients with intraoperative endoleaks demonstrated a trend toward less postoperative aneurysm diameter reduction at 2 years (43.8% vs. 74.5%, P = .104). Conclusion: The presence of a type I or a type II endoleak during EVAR significantly increases the likelihood of a postoperative endoleak and should prompt a high degree of suspicion during follow-up.