OBJECTIVE: The introduction and development of the embolic protecting device (EPD) has resulted in a decreased rate of stroke after carotid artery stenting (CAS). The authors performed a retrospective study to investigate the risk factors for developing large emboli after CAS which can lead to ischemic events. METHODS: A total of 35 consecutive patients who underwent CAS between January 2009 and March 2012 were included in this study. Patients were divided into two groups including those with small emboli (group A; grade 1, 2) and those with large emboli (group B; grade 3, 4). The size and number of emboli were assigned one of four grades (1=no clots, 2=1 or 2 small clots, 3=more than 3 small clots, 4=large clots) by microscopic observation of the EPD after CAS. We compared demographic characteristics, medical history, and angiographic findings of each group. RESULTS: Thirty-five patients underwent CAS, and technical success was achieved in all cases. Twenty-three patients were included in group A and 12 patients in group B. Our results demonstrated that advanced age [odds ratio (OR) 1.24; 95% confidence interval (CI) 1.01-1.52; p=0.044] and smoking (OR 42.06; CI 2.828-625.65, p=0.006) were independent risk factors for developing large emboli after CAS. CONCLUSION: In patients with carotid artery stenosis treated with CAS, advanced age and smoking increased the number and size of emboli. Although use of an EPD is controversial, it may be useful in CAS in patients with risk factors for large emboli in order to reduce the risk of ischemic events.
Carotid Arteries ; Carotid Stenosis ; Embolic Protection Devices ; Humans ; Retrospective Studies ; Risk Factors ; Smoke ; Smoking ; Stents ; Stroke

To date, there have been many clinical trials to examine carotid endarterectomy (CEA) for its clinical usefulness, and-in comparison with the results of CEA-carotid artery stenting (CAS) for its clinical impact. The paper summarizes the guideline for extracranial carotid arterial disease, providing the classification of recommendation and level of evidence. Extracranial carotid artery is unique in its geometry, hemodynamics, and hemorheologic characteristics. Invasive or non-invasive imaging methods for the extracranial carotid arterial disease should be used appropriately for decision making.
Arteries ; Carotid Arteries ; Carotid Artery Diseases ; Decision Making ; Embolic Protection Devices ; Endarterectomy ; Endarterectomy, Carotid ; Hemodynamics ; Stents

The authors present a case in which macro-embolus from the ruptured atheromatous plaque developed during carotid artery stenting (CAS). A 63-year-old man who had suffered a left middle cerebral artery territory infarction had significant proximal left internal carotid artery stenosis required CAS procedure. Immediate after stent deployment, the patient showed abrupt neurological deterioration with 12 x 3 mm sized macro-embolus which was caught by the embolus protection device (EPD). Retrieval of the macro-embolus was performed safely and the patient recovered to pre-procedure status. Macro-embolus can be resulted during the CAS. The EPD can capture the macro-embolus and safe removal is technically feasible.
Angioplasty ; Carotid Arteries ; Carotid Stenosis ; Embolic Protection Devices ; Embolism ; Humans ; Infarction ; Middle Cerebral Artery ; Stents

PURPOSE: Since we reported about a landmark technique to reopen an occluded subclavian artery, we have faced difficulty in using protection devices in the vertebral artery to protect against thromboembolism from the reversed steal phenomenon after angioplasty and stenting. Therefore, we are presenting an optimal solution in using a protection device while recanalizing the occluded subclavian artery. MATERIALS AND METHODS: Among 21 cases of stenting for subclavian artery steno-occlusion, we applied the landmark technique at the opposite end of an occluded segment in 4 patients and used a protection device in two patients. Because the embolic protection device was placed in the vertebral artery via the brachial artery, optimal angioplasty and stenting via the brachial route were limited. Therefore, angioplasty via the trans-brachial approach was needed to be followed by stenting through a trans-femoral approach. We estimated the safe and optimal steps for placement and retrieval of the protection devices in addition to stenting. RESULTS: The procedure was safely performed when a stent was introduced via the femoral artery and a protection device was used via the brachial artery. However, in cases when a guidewire wasn't passed via the transfemoral route, simultaneous use of two systems via the brachial route could cause friction of devices or trapping of protection devices in a stent. When a protection device was trapped in a deployed stent, we retrieved the protection device with a 4F angiocatheter by selectively rotating the catheter tip. To avoid such procedural difficulty, we recommend using a transbrachial angioplasty followed by trans-femoral stenting while placing the protection device in the vertebral artery via the trans-brachial route. CONCLUSION: If a guidewire is not passed through using a trans-femoral approach while performing the landmark technique, changing the stenting route from brachial to the femoral artery can be useful after securing the lumen in the occluded subclavian artery after angioplasty via the brachial artery.
Angioplasty ; Brachial Artery ; Catheters ; Embolic Protection Devices ; Endovascular Procedures ; Femoral Artery ; Friction ; Humans ; Stents ; Subclavian Artery ; Thromboembolism ; Vertebral Artery

OBJECTIVE: The main concern during transfemoral carotid artery stenting (CAS) is preventing cerebral embolus dislodgement. We compared clinical outcomes and intraprocedural embolization rates of CAS using a distal filter protection device or proximal balloon occlusion device. METHODS: From January 2011 to March 2015, a series of 58 patients with symptomatic or asymptomatic internal carotid artery stenosis > or =70% were treated with CAS with embolic protection device in single center. All patients underwent post-CAS diffusion-weighted magnetic resonance imaging (DW-MRI) to detect new ischemic lesions. We compared clinical outcomes and postprocedural embolization rates. RESULTS: CAS was performed in all 61 patients. Distal filter protection success rate was 96.6% (28/29), whose mean age was 70.9 years, and mean stenosis was 81%. Their preprocedural infarction rate was 39% (11/28). Subsequent DW-MRI revealed 96 new ischemic lesions in 71% (20/28) patients. In contrast, the proximal balloon occlusion device success rate was 93.8% (30/32), whose mean age was 68.8 years and mean stenosis was 86%. Preprocedure infarction rate was 47% (14/30). DW-MRI revealed 45 new ischemic lesions in 57% (17/30) patients. Compared with distal filter protection device, proximal balloon occlusion device resulted in fewer ischemic lesions per patient (p=0.028). In each group, type of stent during CAS had no significant effect on number of periprocedural embolisms. Only 2 neurologic events occurred in the successfully treated patients (one from each group). CONCLUSION: Transfemoral CAS with proximal balloon occlusion device achieves good results. Compared with distal filter protection, proximal balloon occlusion might be more effective in reducing cerebral embolism during CAS.
Balloon Occlusion* ; Carotid Arteries* ; Carotid Stenosis ; Cerebral Infarction ; Constriction, Pathologic ; Embolic Protection Devices ; Embolism ; Humans ; Infarction ; Intracranial Embolism ; Magnetic Resonance Imaging ; Stents*

Renal artery disease is one of the significant factors that lead to compromise renal function and/or aggravate hypertension in the elderly population. Since the non-surgical treatment of renal artery stenosis, percutaneous transluminal renal angioplasty, is available, it is possible to cure the decreased renal function and exacerbated hypertension. However, bilateral renal artery occlusion (BRAO) that brings about anuria and azotemia is rare. In this communication, we'd like to describe a patient who developed acute renal failure due to BRAO. His renal function was completely recovered after successful implantation of stents into both renal arteries. We are unaware of prior reports documenting the beneficial effect of a distal embolic protection device, the PercuSurge GuardWire system (Medtronic, Minneapolis, MN, USA), in a clinical setting as described here. The GuardWire arm, a device for transient distal balloon occlusion during angioplasty or stent placement, allows recovery of any liberated plaque by aspiration before restoration of antegrade flow, and thereby performs a double service. We'd like to strongly recommend that stent implantation with adjunctive distal protection is essential to obtain a complete restoration of distal blood flow although there is sufficient collateral blood flow in elderly patients with BRAO and azotemia.
Acute Kidney Injury ; Aged ; Angioplasty ; Anuria ; Arm ; Azotemia ; Balloon Occlusion ; Embolic Protection Devices* ; Humans ; Hypertension ; Renal Artery Obstruction ; Renal Artery* ; Stents*

BACKGROUND AND OBJECTIVES: Neurologic intolerance (NI) is defined as the occurrence of neurological symptoms during carotid artery stenting (CAS). Because NI is inevitable problem, it may be helpful to anticipate its occurrence. So, we studied factors associated with NI during proximal protected CAS. METHODS: We retrospectively analyzed all consecutive patients underwent proximal protected CAS from August 2012 to January 2017. RESULTS: We included total 123 patients (109 males, 72±8 years old). The total procedure time was 43±12 minutes, and mean occlusion time was 4.8±1.2 minutes. We divided CAS patients into 2 groups according to presence of NI; neurologic tolerance (NT; n=74, 60%) and NI (n=49, 40%) groups. After the univariate analysis, symptomatic carotid artery stenosis (p = 0.003), absence of anterior communicating artery (p = 0.015) and low common carotid artery occlusion pressure (CCAOP, p < 0.001) were associated with NI. After the multivariate analysis, NI was significantly associated with symptomatic carotid artery stenosis (odds ratio [OR], 5.549; p = 0.014) and systolic CCAOP≤42 mmHg (OR, 6.461; p < 0.001). In NI group, 43 patients (88%) recovered right after the balloon deflation and 2 patients were normalized within 2 hours. However, 1 had major stroke and 3 had minor strokes in 4 patients with persistent NI ≥24 hours. CONCLUSIONS: About 40% showed NI during the CAS. Most of them (88%, 43 of 49 patients) recovered after the balloon deflation, but stroke incidence was significantly higher in NI group. Symptomatic carotid artery stenosis and systolic CCAOP ≤42 mmHg were significantly associated with the development of NI during proximal protected CAS.
Arteries ; Carotid Arteries ; Carotid Artery, Common ; Carotid Stenosis ; Embolic Protection Devices ; Humans ; Incidence ; Male ; Multivariate Analysis ; Neurologic Manifestations ; Retrospective Studies ; Stents ; Stroke

OBJECTIVESTo study the efficacy of proximal embolic protection device in preventing intracranial artery embolization during carotid artery stenting (CAS) and to evaluate its security and maneuverability.

METHODSFrom October 2007 to July 2008, 23 patients with carotid artery stenosis who were suitable for surgical therapy according to the standards of NASCET or ACAS were enrolled in this clinical research. Among them 19 patients (82.6%) were symptomatic, 6 patients (26.1%) with 50%-70% stenosis and 17 cases (73.9%) with > 70% stenosis. All the patients received carotid angioplasty and stenting under the protection of MO. MA system (one kind of proximal embolic protection device). We recorded the cerebral ischemic time during the procedure and observed neurologic events within 30 days.

RESULTSAll the procedures were performed successfully, the mean carotid artery blocking time was (5.3 +/- 1.2) min. No death or stroke occurred during perioperative period. Two cases of patients developed transient loss of consciousness combined with contralateral limb convulsion, while the common carotid artery was occluded by balloon. Two cases of patients developed bradycardia, sustained 6 hours and 1 week. Plaque debris in the withdrawal blood from carotid artery were found in 9 cases. At 30-day follow-up after CAS, TIA occurred in 1 case, new contralateral stroke occurred in 1 case, the incidence of 30-day stroke and death rate was 4.3%.

CONCLUSIONThe application of proximal embolic protection device in CAS procedure for preventing neurologic complications is safe and effective, especially for severe stenosis and unstable plaque in carotid artery stenting.

Aged ; Aged, 80 and over ; Angioplasty, Balloon ; instrumentation ; methods ; Carotid Stenosis ; surgery ; Embolic Protection Devices ; Female ; Follow-Up Studies ; Humans ; Intracranial Embolism ; etiology ; prevention & control ; Male ; Postoperative Complications ; prevention & control ; Stents ; Treatment Outcome

The use of retrievable inferior vena cava (IVC) filters has markedly increased in the recent years. However, the failure rate for the retrieval of the IVC filters using the endovascular method is reported to be up to 19%. Open surgical removal of the IVC filters is technically challenging and may require longitudinal cavotomy, clamping, and repair of the IVC. Here, we present a case of successful open surgical removal of the IVC filter using minimal cavotomy. This technique is an effective method after a failed endovascular removal attempt.
Constriction ; Methods ; Vena Cava Filters ; Vena Cava, Inferior

The dynamic analysis of the implantation process of a new vena cava filter was carried out by finite element analysis method to reveal the influence of the angle, length, width and thickness of the filter rod on its mechanical properties and the inner wall of the blood vessel. The results showed that the high-stress and high-strain areas of the filter were mainly concentrated in the connection between the filter rod and the filter wire. With the increase of the angle of the filter rod, the maximum equivalent stress and the maximum elastic strain on the filter wall decreased, while the maximum equivalent stress on the vascular wall increased. With the increase of the length of the filter rod, the maximum equivalent stress and strain peak of the filter wall increased, but the maximum equivalent stress of the vessel wall decreased. With the increase of the width and thickness of the filter rod, the maximum equivalent stress of the filter wall, the maximum elastic strain and the maximum equivalent stress of the vessel wall all showed an upward trend. The static safety factor of all filter models was greater than 1, and the structure after implantation was safe and reliable. The results of this study are expected to provide a theoretical basis for the structural optimization and deformation mechanism of the new type vena cava filter.
Finite Element Analysis ; Vena Cava Filters ; Vena Cava, Inferior