Do the Advantages of the FiberNet(®) Embolic Protection Device Translate into Technical Success and Comparable Event Rates in Carotid Artery Stenting?

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.

Intravascular ultrasound assessment of iliac stent procedures.

PURPOSE: To determine whether intravascular ultrasound (IVUS) is more sensitive in identifying incomplete stent deployment or mechanical disruption compared to angiography. METHODS: Over a 9-month period, 44 patients (25 men; mean age 63 years, range 36-88) treated for common or external iliac artery stenoses with balloon angioplasty and stenting underwent IVUS interrogation following completion arteriography. RESULTS: One hundred nine stents were deployed in the 44 patients. Of these, 29 (27%) stents (in 45% of patients) were found by IVUS to be incompletely deployed or to have an associated mechanical disruption despite a normal completion arteriogram. Further treatment (repeat dilation or additional stenting) was performed in 28 cases; 1 hemodynamically insignificant dissection was not treated. Twenty-six (93%) of these interventions were successful as determined by IVUS; 2 underexpanded stents did not respond to redilation. CONCLUSIONS: Incomplete stent deployment or mechanical problems associated with stenting were common in this study, occurring in nearly half of the patients. IVUS has clinical utility in identifying incomplete deployment or mechanical problems in stents with an increased sensitivity compared to contrast angiography.

Carotid artery disease: natural history, diagnosis, and therapy.

Stroke remains a major complication of atherosclerotic cerebrovascular disease, with extracranial carotid occlusive disease accounting for nearly one-third of all events. Although historical symptoms and physical examination findings are important, objective testing with carotid duplex ultrasonography and magnetic resonance arteriography represent the foundation for therapeutic decision making. Contrast arteriography is playing a decreasing role in the evaluation of patients with carotid artery disease. Options for therapy, based on the presence or absence of symptoms and degree of stenosis, include antiplatelet therapy with cardiovascular risk factor modification, carotid endarterectomy, and more recently, endovascular therapy.

Angioplasty and primary stenting of the subclavian, innominate, and common carotid arteries in 83 patients.

PURPOSE: The initial and long-term results of angioplasty and primary stenting for the treatment of occlusive lesions involving the supra-aortic trunks were studied. METHODS: All patients in whom angioplasty and stenting of the supra-aortic trunks was attempted were included in a prospective registry. Results are, therefore, reported on an intent-to-treat basis. The preprocedural and postprocedural clinical records, arteriograms, and noninvasive vascular laboratory examinations of 83 patients (41 men [49.4%] and 42 women [50.6%]; mean age at intervention, 63 years) in whom endovascular repair of the subclavian (66, 75.9%), left common carotid (14, 16.1%), and innominate (7, 8.0%) arteries was attempted were retrospectively reviewed. RESULTS: Initial technical success was achieved in 82 of 87 procedures (94.3%). The inability to cross 4 complete subclavian occlusions and the iatrogenic dissection of 1 common carotid artery lesion accounted for the 5 initial failures. Complications occurred in 17.8% of 73 subclavian and innominate procedures, including access-site bleeding in 6 and distal embolization in 2. Ischemic strokes occurred in 2 of 14 common carotid interventions (14.3%), both of which were performed in conjunction with ipsilateral carotid bifurcation endarterectomy. The 30-day mortality rate was 4.8% for the entire group. By means of life-table analysis, 84% of the subclavian and innominate interventions, including initial failures, remain patent by objective means at 35 months. No patients have required reintervention or surgical conversion for recurrence of symptoms. Of the 11 patients available for follow-up study who underwent common carotid interventions, 10 remain stroke-free at a mean of 14.3 months. CONCLUSION: Angioplasty and primary stenting of the subclavian and innominate arteries can be performed with relative safety and expectations of satisfactory midterm success. Endovascular repair of common carotid artery lesions can be performed with a high degree of technical success, but should be approached with caution when performed in conjunction with ipsilateral bifurcation endarterectomy.

Percutaneous transluminal angioplasty and primary stenting of the iliac arteries in 288 patients.

PURPOSE: This study reports the initial and late results of percutaneous transluminal angioplasty (PTA) and intravascular stenting for atherosclerotic occlusive disease of the iliac arteries. METHODS: The preprocedural and postprocedural clinical records, arteriograms, segmental limb pressure measurements (ankle-brachial [ABI] and thigh-brachial [TBI] indexes), and pulse volume recordings of 288 patients who underwent PTA and primary stenting of the common iliac (354, 69.4%) and external iliac (156, 30.6%) arteries were reviewed. Initial and late clinical, hemodynamic, and angiographic success were assessed by objective criteria. Data on patients who underwent unsuccessful attempts at iliac stent placement are unavailable; results are not reported on an intent-to-treat basis. RESULTS: Clinical follow-up data (mean, 11.9 months) are available for 268 of 288 patients (93.1%) and for 394 of 424 limbs (92.9%). The initial success rates, as determined by TBI, ABI, and clinical limb status, were 90.2%, 87.8%, and 74.6%, respectively. The Kaplan-Meier estimates of angiographic patency (101 arteries) were 96%, 81%, and 73% at 6, 12, and 24 months. Cumulative patency rates were 84%, 76%, and 57% on the basis of TBI, ABI, and clinical limb status at 24 months. Factors associated with initial success included the need for multiple stents (p = 0.0001), a higher degree of initial stenosis (p = 0.0001), lower severity of baseline ischemia (p = 0.007), younger age (p = 0.0015), and the preprocedural patency of the ipsilateral superficial femoral artery (p = 0.002). A higher degree of initial stenosis (p < 0.001) and superficial femoral artery patency (p = 0.004) were also associated with late success. CONCLUSIONS: PTA and stenting of the iliac arteries is associated with reasonable angiographic, hemodynamic, and clinical success. The outcome is favorably affected by higher initial severity of stenosis and greater extent of disease, lower severity of baseline ischemia, younger age, and by patency of the ipsilateral superficial femoral artery.

Endovascular management of unusual aneurysms of the axillary and subclavian arteries.

PURPOSE: Aneurysms of the upper extremity arteries are uncommon and may be difficult to manage with standard surgical techniques. We report the exclusion of three axillary-subclavian aneurysms with covered stents. METHODS AND RESULTS: Palmaz stents were covered with either polytetrafluoroethylene (2 cases) or brachial vein and deployed to exclude pseudoaneurysms in 1 axillary (ruptured) and 2 left subclavian arteries. Two of the patients had advanced cancer and died within 52 days and 3 months of treatment, but their aneurysms were occluded at the time of their death. The repair in the third patient is patent at 9 months. CONCLUSIONS: Endovascular exclusion of axillary and subclavian aneurysms with covered stents may offer a useful alternative to operative repair, particularly in patients with significant comorbidities.

Chronic traumatic thoracic aneurysm: report of two cases with the question of timing for surgical intervention.

We report on two symptom-free patients with chronic thoracic aneurysms related to prior trauma and address the timing for surgical intervention. In addition, we reviewed our institutional experience with similar cases for the period 1970 to 1990. Although natural history data remain incomplete, we propose that in the setting of improved imaging modalities, it may be reasonable to manage this group of patients nonoperatively and intervene surgically only when symptoms develop or there is radiologic evidence of aneurysm change.

Imaging spectrum of thrombo-occlusive vascular disease associated with antiphospholipid antibodies.

The association of antiphospholipid antibodies with unexplained thrombo-occlusive vascular disease is well known but often remains unrecognized. The most well-studied clinical manifestation is venous thrombosis, but arterial occlusive disease involving multiple sites is also well documented. Twenty-six cases of thrombo-occlusive disease were observed in 22 patients over a 3-year period. Magnetic resonance imaging and angiography were used to make the diagnoses. None of the patients who underwent angiography or venography developed thrombolytic disease related to the puncture site. This group of patients with antiphospholipid antibody syndrome had a wide distribution of arterial and venous thrombotic disease. Radiologists should consider antiphospholipid antibody syndrome in the differential diagnosis when evaluating thrombo-occlusive vascular disease that is unexpected or occurs without risk factors. Knowledge of antiphospholipid antibody status has important implications for prognosis and therapy.

Fistulous pseudoaneurysm complicating surgical accessory pathway interruption for Wolff-Parkinson-White syndrome.

Pseudoaneurysms of the left ventricle are unusual operative complications that have commonly been associated with replacement of the mitral valve. In this report, we describe a 31-year-old man who was referred to our institution because of atypical chest pain. He had previously undergone three operations for ablation of an accessory pathway because of Wolff-Parkinson-White syndrome. A pseudoaneurysm of the left ventricle was noted on transesophageal echocardiography, biplanar left ventriculography, and ultrafast cine computed tomography of the heart. Elective surgical repair was successful. Although rare, this case demonstrates an unusual but potentially serious complication of surgical treatment of Wolff-Parkinson-White syndrome.

Predictive value of transcutaneous oxygen pressure and amputation success by use of supine and elevation measurements.

The purpose of this study was to determine if transcutaneous oxygen pressure (tcPO2) measurements can be used to predict amputation site healing in lower limbs with arterial occlusive disease. We measured tcPO2 (supine and with limb elevation) in 90 limbs before amputation and reviewed their subsequent clinical course. Of these, 52 (57%) successfully healed, 21 (23%) failed, and 17 (18%) exhibited delayed healing. Limbs with delayed healing or failure had significantly lower tcPO2 values than values of those that healed. A tcPO2 greater than or equal to 40 torr was associated with primary or delayed healing in 51 of 52 limbs (98%), and a tcPO2 value of less than 20 torr was universally associated with failure. For patients with a tcPO2 between 20 and 40 torr, tcPO2 measurements obtained during limb elevation improved the predictability of outcome. We conclude that supine tcPO2 measurements can help predict amputation site healing, and that tcPO2 measurement during limb elevation improves predictability in limbs with borderline supine tcPO2 values.

The prevalence of vascular occlusive disease associated with antiphospholipid syndromes.

The association of anticardiolipin antibodies (aCL) with unexplained vascular occlusive disease (VOD) is well known. We reviewed the records of 102 consecutive patients seen over a 9 months period who had positive IgG or IgM aCL to determine the frequency and types of VOD in this unselected group of patients. Lupus anticoagulant was detectable in 17 of 67 (25%) patients tested. VOD occurred in 80 of 102 (78%) aCL-positive patients comprised of 17 (16.7%) with systemic venous VOD or pulmonary embolism; 27 (26.5%) with cerebral VOD: 11 (10.8%) with systemic arterial VOD; 3 (2.9%) with coronary thrombosis; and 5 (4.9%) with visceral venous or arterial VOD. Of the 19 obstetric patients with positive aCL, 17 (89%) had at least one unexplained fetal loss and 8 of the 17 (47%) had multiple or recurrent fetal losses. Twelve (11.7%) of the 102 patients met the ACR criteria for systemic lupus erythematosus (SLE). Additionally, 12 (11.7%) patients were identified as nonSLE or undifferentiated connective tissue disease (CTD). The remaining 78 (76%) had no known underlying disease (primary antiphospholipid syndrome). We conclude that IgG and IgM aCL with or without lupus anticoagulant are associated with diverse types of VOD but cerebral VOD appears predominant. aCL-associated unexplained VOD occurs frequently in patients without evidence of CTD-65 of 80 (81%) in our series. Testing for aCL is essential for identifying patients with unexplained VOD, and it should be performed in prospective clinical studies of such patients to better define the pathogenic role of aCL in the natural history of unexplained VOD.

Accelerated atherosclerosis, aneurysmal disease, and aortitis: possible pathogenetic association with cocaine abuse.

Cocaine abuse and its association with vascular disease has become common in the medical literature. A variety of vascular problems have been described including neurovascular complications, cardiovascular complications, aortic dissection, venous thrombosis, mesenteric artery thrombosis, and renal infarction. The pathogenesis of these vascular complications has largely been related to increased adrenergic activity leading to vasospasm. Interaction of cocaine with the vascular endothelium resulting in thrombosis or vasculitis has also been suggested. We report a case of diffuse aneurysmal change of the aorta associated with an atypical inflammatory component consistent with possible cocaine induced vasculitis.