New technologies for CAS that might overcome the burden of microembolization

Microembolization during carotid artery stenting (CAS) is the result of embolic events shown by intraprocedural transcranial Doppler (TCD) or postprocedure diffusion-weighted MRI that do not lead to acute neurological deficit. Although the long term clinical outcome of these silent infarcts is not yet well established, there is increasing evidence that these events could be associated with neurological impairments, such as cognitive decline. In order to prevent microembolization due to excessive catheter manipulation at the time of guiding catheter placement in patients with challenging anatomy, a cervical access system with flow reversal protection was developed. Other embolic events are often seen as the result of plaque protrusion through stent struts. A new type of stent, so-called "hybrid" stent, incorporates the flexibility and conformability of an open-cell stent as well as plaque coverage seen with a close-cell stent, with the goal of achieving better plaque stabilization reducing macro and microembolization, while maintaining original vessel anatomy and flow hemodynamic. At the present time there are three different stents under investigation or this application.

How safe are carotid endarterectomy and carotid artery stenting in the early period after carotid-related cerebral ischemia?

Timing of treatment in carotid artery disease is still a matter of debate. So far there is controversial literature available concerning the safety of rapid treatment after a qualifying neurological event. Carotid endarterectomy turned out to be more effective in stroke prevention when carried out closer after the onset of symptoms. The initial "two weeks" cut off for surgery meanwhile turned into a "as soon as possible" treatment policy. In case of a cerebral infarction it seems reasonable, however, to delay surgery. Less evidence exists about the ideal timing of carotid artery stenting. Data analysis from the Carotid Stenosis Trialists' Collaboration showed that the early days after plaque rupture carry a high risk for periprocedural complications after carotid artery stenting. The analysis of a large register series showed, that carotid artery stenting carried a significantly higher risk for complications in patients with and without cerebral infarction when performed within 48 hours after the onset of symptoms.

Patient characteristics and outcomes of carotid endarterectomy and carotid artery stenting: analysis of the German mandatory national quality assurance registry - 2003 to 2014

AIM

In Germany, every surgical or endovascular procedure on the extracranial carotid artery is documented in a mandatory quality assurance registry. The purpose of this study is to describe the patient characteristics, the indications for treatment, and the short-term outcomes as well as to analyse the corresponding trends from 2003 to 2014.

METHODS

Data on demographics, peri-procedural measures, and outcomes were extracted from the annual quality reports published by the Federal Agency for Quality Assurance and the Institute for Applied Quality Improvement and Research in Health Care. Data were available from 2003 to 2014 for carotid endarterectomy (CEA) and from 2012 to 2014 for carotid artery stenting (CAS). The primary outcome event of this study is any stroke or death until discharge from hospital. Temporal trends of categorical variables were statistically analysed using the Cochran-Armitage test for trend.

RESULTS

Between 2003 and 2014, 309,405 CEAs and 18,047 CAS procedures were documented in the database; 68.1% of all patients were male. The mean age of patients treated with CEA increased from 68.9 years in 2003 to 70.9 years in 2014. The proportion of patients with ASA stages III to V increased from 65% to 71% in CEA, whereas it decreased from 44% to 41% in CAS patients. 53.1% of all CEAs were performed for asymptomatic patients (group A), 34.4% for symptomatic patients treated electively (group B), and 11.2% a in a collective group including other indications for CEA or CAS (such as recurrent stenosis, carotid aneurysms, emergency treatment due to stroke-in-evolution). The corresponding data for CAS are 49.3%, 26.1% and 26.3% respectively. In group B, the interval between the neurological index event and CEA decreased from 28 to 8 days (P<0.001). In patients treated with CAS, this interval was 9 days in 2012 (no further data available). On average, 67.1% and 48.2% of surgically treated patients as well as 77.8% and 69.8% of CAS patients were neurologically assessed before and after the procedure, respectively. From 2003 to 2014, CEA procedures were performed more frequently in locoregional anesthesia (10.1% to 29.1%, P<0.001). The same trend was observed for the application of the eversion technique (37.0% to 41.6%, P<0.001), the neurophysiological monitoring (49.8% to 61.8%, P<0.001), and the intra-procedural assessment of the treated artery (44.5% to 69.7%, P<0.001). In contrast, shunting was used less frequently (48.1% to 43.0%, P<0.001). Averagely 95.7% of all endovascular procedures were performed using stent-angioplasty. In 54.2% a protection device was used. Nitinol and bare metal stents were used in 74.1% and 21.4% of cases, respectively. The in-hospital rate of any stroke or death decreased from 2.0% to 1.1% in asymptomatic patients treated with CEA without a contralateral stenosis ≥75% or occlusion, P<0.001). In patients treated with CAS this rate did not increase (1.7% to 1.8%, p=0.909). The corresponding rates in CEA and CAS patients with severe contralateral stenosis or occlusion varied between 1.9%-3.1% and 2.2%-2.6%, respectively. In symptomatic patients (group B) with a stenosis of 50 percent or more, the rate of any stroke or death decreased significantly after CEA from 4.2% to 2.4% (P<0.001) and remained stable after CAS (3.9% to 3.5%, P=0.577).

CONCLUSION

This report on 327,452 carotid procedures analysed one of the largest quality registries on CEA and CAS worldwide. Data indicate that treated patients became older and sicker, whereas in contrast, the in-hospital rates of stroke or death are decreasing over time.

Recruiting RCTs comparing CAS, CEA and best medical treatment for asymptomatic carotid stenosis

The present paper summarizes the similarities and differences between recent and ongoing randomized controlled trials on optimal treatment of patients with severe but asymptomatic carotid stenosis. Protocol details will be discussed as well as needs for outcome and especially differentiation between patients with a low versus high risk for future events.

Stroke risk in the early period after carotid related symptoms: a systematic review

Current guidelines recommend performing carotid endarterectomy in patients with symptomatic carotid disease as soon as possible after the neurological index event. However, early stroke risk has not been well documented for this patient group. We therefore conducted a systematic analysis of the current literature on the recurrent risk of ischemic events in patients with symptomatic carotid stenosis. Systematic review was performed by searching the MEDLINE® database from 1950 until June 8, 2015 (key words: cerebral ischemia, transient ischemic attack, amaurosis fugax, stroke, symptomatic carotid stenosis, recurrent risk, outcome, prognosis, follow-up, cohort and natural history). All studies reporting stroke risks in patients with symptomatic carotid stenosis after neurologic index events within a period of 7 days were included. Cumulative stroke risks with 95% confidence intervals after a neurologic index event were recalculated at 2-3, 7, 14 and 30 days and a meta-analysis including an analysis of heterogeneity were performed using the statistical package R and Excel for Mac 2003. Ten studies with a total number of 2634 patients were included. Results of an overall stroke risk were as follows: 2.0-17.2% at 2-3 days, 0-22.1% at 7 days, 0-29.6% at 14 days and 0-11.1% at 30 days in patients with a symptomatic extracranial carotid stenosis. The pooled stroke risk in the six studies with active follow-up was 6.0% (95% CI 2.4-14.4) at 2-3 days, 10.9% (6.1-18.7) at 7 days and 17.6% (9.7-29.9) at 14 days. Pooled stroke risk in the three studies with uncensored populations was even higher with 6.4% (1.5-23.8%) at 2-3 days, 19.5% (12.7-28.7) at 7 days and 26.1% (20.6-32.5%) at 14 days. Significant heterogeneity (P<0.001) could be explained by the different inclusion criteria and the study's design. Retrospective studies with passive follow-up had the lowest stroke risk whereas prospective studies with active follow-up and without bias through early intervention by carotid endarterectomy or carotid stenting had the highest stroke risk. The risk of recurrence of cerebrovascular events in patients with symptomatic carotid stenosis within the first days after a neurologic index event is as high as 6.4% (1.5-23.8), 19.5% (12.7-28.7) and 26.1% (20.6-32.5) after 2-3, 7 and 14 days respectively. Patients with a symptomatic carotid stenosis are therefore at a very high risk of a definitive stroke. Recommendations by current guidelines to perform carotid endarterectomy as soon as possible after the neurologic index event are therefore justified.

Carotid angiographic characteristics in the CREST trial were major contributors to periprocedural stroke and death differences between carotid artery stenting and carotid endarterectomy

OBJECTIVE

The Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) demonstrated a higher periprocedural stroke and death (S+D) rate among patients randomized to carotid artery stenting (CAS) than to carotid endarterectomy (CEA). Herein, we seek factors that affect the CAS-CEA treatment differences and potentially to identify a subgroup of patients for whom CAS and CEA have equivalent periprocedural S+D risk.

METHODS

Patient and arterial characteristics were assessed as effect modifiers of the CAS-CEA treatment difference in 2502 patients by the addition of factor-by-treatment interaction terms to a logistic regression model.

RESULTS

Lesion length and lesions that were contiguous or were sequential and noncontiguous extending remote from the bulb were identified as influencing the CAS-to-CEA S+D treatment difference. For those with longer lesion length (≥12.85 mm), the risk of CAS was higher than that of CEA (odds ratio [OR], 3.42; 95% confidence interval [CI], 1.19-9.78). Among patients with sequential or remote lesions extending beyond the bulb, the risk for S+D was higher for CAS relative to CEA (OR, 9.01; 95% CI, 1.20-67.8). For the 37% of patients with lesions that were both short and contiguous, the odds of S+D in those treated with CAS was nonsignificantly 28% lower than for CEA (OR, 0.72; 95% CI, 0.21-2.46).

CONCLUSIONS

The higher S+D risk for those treated with CAS appears to be largely isolated to those with longer lesion length and/or those with sequential and remote lesions. In the absence of those lesion characteristics, CAS appears to be as safe as CEA with regard to periprocedural risk of S+D.

Physician-initiated prospective Italian Registry of carotid stenting with the C-Guard mesh-stent: the IRON-Guard registry. Rationale and design

According to the World Health Organization, every year, 5 million peoples die for stroke and another 5 million are permanently disabled. Although there are many causes of acute stroke, a common treatable cause of acute stroke is atheromatous narrowing at the carotid bifurcation. Carotid endarterectomy is still the standard of car, even if carotid artery stenting (CAS) has become an effective, less invasive alterantive. Unfortunately, CAS procedure is not yet perfect; regardless the use of an embolic protection device (EPD), percutaneous treatment has been correlated with a risk of cerebral ischemic events related to distal embolization. The objective of the IRON-Guard Registry is to evaluate the clinical outcome of treatment by means of stenting with the C-Guard (InspireMD, Boston, MA, USA) in subjects requiring CAS due to significant extracranial carotid artery stenosis with a physician-initiated, Italian, prospective, multicenter, single-arm study. A total of 200 enrolled subjects divided over different centers are planned to be enrolled. CAS will performed by implanting of C-Guard stent. Procedure will be performed according to the physician's standard of care. Standard procedures will be followed based on the Instructions for Use, for the C-Guard device of Inspire. The primary endpoint of this study is the 30-day rate of major adverse events (MAE), defined as the cumulative incidence of any periprocedural (≤30 days postprocedure) death, stroke or myocardial infarction. Secondary endpoints are rate of late ipsilateral stroke (31 through 365 days), system technical success, device malfunctions, major adverse events (MAEs), serious device-related and procedure-related adverse events, target lesion revascularization, and in-stent restenosis rates.

Prognostic Impact of Blood Pressure Variability on Aortic Dissection Patients After Endovascular Therapy

Hypertension has been deemed as a pivotal risk factor for the development of aortic dissection; however, the importance and prognostic significance of blood pressure variability (BPV) in aortic dissection are always ignored. A total of 173 acute type B aortic dissection patients were enrolled in and retrospectively reviewed between January 2009 and November 2013. There were 74 patients with high BPV and 99 with low BPV stratified by preoperative mean BPV. Technical success was achieved in all patients. The proportions of hypertension and general anesthesia were significantly higher in the high BPV group (70.3% vs 55.6% and 77% vs 62.6%, P = 0.049 and 0.043, respectively). The risk of aorta-related death in the high BPV group was apparently higher than the low BPV group (28.4% vs 9.1%, P = 0.001). By performing multivariable logistic regression, we found history of hypertension was likely to be a risk factor of BPV (95% confidence interval [CI]: 1.010-3.911), and high BPV was an independent predictor of aorta-related death (95% CI: 1.671-9.587). The difference of aorta-related mortality was pronounced between high and low BPV subgroups regardless of the refractory hypertension (41.4% vs 14.3% and 20.0% vs 7.0%, P = 0.023 and 0.037, respectively). The thrombosis ratio of false lumen was significantly higher in the low BPV group at 3-month (72.4 ± 17.5% vs 51.8 ± 11.6%, P < 0.001) and 6-month (86.4 ± 9.1% vs 69.7 ± 7.9%, P < 0.001). High BPV is an independent risk factor for the prognosis of aortic dissection. Further studies on BPV might provide new preventive and therapeutic strategies for aortic dissection.

Mechanism of Procedural Stroke Following Carotid Endarterectomy or Carotid Artery Stenting Within the International Carotid Stenting Study (ICSS) Randomised Trial

OBJECTIVE

To decrease the procedural risk of carotid revascularisation it is crucial to understand the mechanisms of procedural stroke. This study analysed the features of procedural strokes associated with carotid artery stenting (CAS) and carotid endarterectomy (CEA) within the International Carotid Stenting Study (ICSS) to identify the underlying pathophysiological mechanism.

MATERIALS AND METHODS

Patients with recently symptomatic carotid stenosis (1,713) were randomly allocated to CAS or CEA. Procedural strokes were classified by type (ischaemic or haemorrhagic), time of onset (intraprocedural or after the procedure), side (ipsilateral or contralateral), severity (disabling or non-disabling), and patency of the treated artery. Only patients in whom the allocated treatment was initiated were included. The most likely pathophysiological mechanism was determined using the following classification system: (1) carotid-embolic, (2) haemodynamic, (3) thrombosis or occlusion of the revascularised carotid artery, (4) hyperperfusion, (5) cardio-embolic, (6) multiple, and (7) undetermined.

RESULTS

Procedural stroke occurred within 30 days of revascularisation in 85 patients (CAS 58 out of 791 and CEA 27 out of 819). Strokes were predominately ischaemic (77; 56 CAS and 21 CEA), after the procedure (57; 37 CAS and 20 CEA), ipsilateral to the treated artery (77; 52 CAS and 25 CEA), and non-disabling (47; 36 CAS and 11 CEA). Mechanisms of stroke were carotid-embolic (14; 10 CAS and 4 CEA), haemodynamic (20; 15 CAS and 5 CEA), thrombosis or occlusion of the carotid artery (15; 11 CAS and 4 CEA), hyperperfusion (9; 3 CAS and 6 CEA), cardio-embolic (5; 2 CAS and 3 CEA) and multiple causes (3; 3 CAS). In 19 patients (14 CAS and 5 CEA) the cause of stroke remained undetermined.

CONCLUSION

Although the mechanism of procedural stroke in both CAS and CEA is diverse, haemodynamic disturbance is an important mechanism. Careful attention to blood pressure control could lower the incidence of procedural stroke.

Impact of Inherited Prothrombotic Disorders on the Long-Term Clinical Outcome of Percutaneous Transluminal Angioplasty in Patients with Diabetes

The aim of our study was to analyse inherited thrombotic disorders that influence the long-term outcome of PTA. Methods. Diabetic patients with peripheral arterial disease (PAD) treated by PTA in our centre between 2008 and 2011 were included in the study. Patients were divided into unsuccessful PTA group (75 patients), successful PTA group (58 patients), and control group (65 patients, with diabetes but no PAD). Diagnosis of inherited thrombotic disorders included mutation in factor V (Leiden), factor II (prothrombin), and mutation in genes for methylenetetrahydrofolate reductase-MTHFR (C677T and A1298C). Results. The genotypic frequency of Leiden allele G1691A was significantly associated with a risk of unsuccessful PTA in comparison with successful PTA group and control group (OR 8.8 (1.1-70.6), p = 0.041, and OR 9.8 (1.2-79.2), p = 0.032, resp.). However, we only observed a trend for the association of the prothrombin allele G20210A and risk of PTA failure. The frequencies of alleles of MTHFR 677 or 1298 did not differ significantly among the groups. Conclusion. Our study showed higher frequency of heterozygous form of Leiden mutation in diabetic patients with unsuccessful outcome of PTA in comparison with patients with successful PTA and diabetic patients without PAD.

Combining superficial femoral artery endovascular treatment with distal vein bypass

AIM

Significant strides have been made using endovascular solutions for the treatment of patients with peripheral vascular disease (PAD) and for tissue loss. But the Trans-Atlantic Inter-Society Consensus (TASC) II classification states that surgery still remains the best solution for C and D lesions, though endovascular management of superficial femoral artery (SFA) can improve inflow for distal origin bypass grafts. Our aim was to evaluate the results of combining endovascular treatment of SFA with distal vein bypass in patients with critical limb ischemia (CLI) and great tissue loss or in the cases where the below-knee endoluminal techniques alone were unable to salvage limbs.

METHODS

A retrospective study of the combined interventions carried out from January 2006 and June 2013 was performed. Twenty-seven angioplasties or selective stentings of SFA combined with popliteal-distal bypass in 23 patients with stage 4, 5 or 6 Rutherford classification were performed. There were 14 men and 9 women, four were bilateral. Mean age was 71.5 years (55-91); 21 (91.3%) were diabetic, and in these, there was almost always deep debridement of necrotic or infected tissue. In 17 cases (62.9%) SFA angioplasty was performed alone, a self-expendable stent was released in the other 10 (37.1%). Distal bypass originated from distal SFA in 5 cases (18.5%), from above-knee popliteal artery in 8 (29.6%) and from below-knee popliteal artery in 14 (51.8%). Reversed saphenous vein was used for bypass in all cases. The target vessel was the posterior tibial artery in 6 cases, anterior tibial artery in 10 and dorsalis pedis in eleven. Follow-up ranged from 4 months to 6 years (with a mean of 37 months).

RESULTS

There were no deaths, but two early graft failures and three major amputations during the perioperative period. Primary patency rate of both the endovascular SFA and the bypass was 81.6% (N.=22) and secondary patency was 88.8% (N.=24). Three years primary and secondary patency rate were, respectively, 74.1% (N.=20) and 81.6% (N.=22). One-year limb salvage rate was 88.8%, at three years was 86.1% and fifteen minor amputations were performed in 13 patients.

CONCLUSION

The endovascular treatment of SFA associated with surgical distal vein bypass is a useful and effective strategy in patients with severe lower extremity arterial disease. This strategy allows a good inflow on SFA in selected patients with the opportunity to perform shorter bypass, use of limited autologous conduit and good expectation of patency.

Angioplasty versus stenting for iliac artery lesions

BACKGROUND

Atherosclerosis of the iliac artery may result in a stenosis or occlusion, which is defined as iliac artery occlusive disease. A range of surgical and endovascular treatment options are available. Open surgical procedures have excellent patency rates but at the cost of substantial morbidity and mortality. Endovascular treatment has good safety and short-term efficacy with decreased morbidity, complications and costs compared with open surgical procedures. Both percutaneous transluminal angioplasty (PTA) and stenting are commonly used endovascular treatment options for iliac artery occlusive disease. A stenotic or occlusive lesion of the iliac artery can be treated successfully by PTA alone. If PTA alone is technically unsuccessful, additional stent placement is indicated. Alternatively, a stent could be placed primarily to treat an iliac artery stenosis or occlusion (primary stenting, PS). However, there is limited evidence to prove which endovascular treatment strategy is superior for stenotic and occlusive lesions of the iliac arteries.

OBJECTIVES

To assess the effects of percutaneous transluminal angioplasty versus primary stenting for stenotic and occlusive lesions of the iliac artery.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched April 2015) and Cochrane Register of Studies (CRS) (2015, Issue 3). The TSC searched trial databases for details of ongoing and unpublished studies.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing percutaneous transluminal angioplasty and primary stenting for iliac artery occlusive disease. We excluded quasi-randomised trials, case reports, case-control or cohort studies. We excluded no studies based on the language of publication.

DATA COLLECTION AND ANALYSIS

Two authors (JB, NA) independently selected suitable trials. JB and HJ independently performed data extraction and trial quality assessment. When there was disagreement, consensus would be reached first by discussion among both authors and, if still no consensus could be reached, through consultation with BF.

MAIN RESULTS

We identified two RCTs with a combined total of 397 participants as meeting the selection criteria. One study included mostly stenotic lesions (95%), whereas the second study included only iliac artery occlusions. Both studies were of moderate methodological quality with some risk of bias relating to selective reporting and non-blinding of participants and personnel. The overall quality of evidence was low due to the small number of included studies, the differences in study populations and definitions of the outcome variables. Due to the heterogeneity among these two studies it was not possible to pool the data. Percutaneous transluminal angioplasty (PTA) with selective stenting and primary stenting (PS) resulted in similar improvement in the stage of peripheral arterial occlusive disease according to Rutherford's criteria, resolution of symptoms and signs, improvement of quality of life, technical success of the procedure and patency of the treated vessel. Improvement in walking distance as reported by the patient, measured claudication distance, ulcer healing, major amputation-free survival and delayed complications (> 72 hours) were not reported in either of the studies. In one trial, PTA of iliac artery occlusions resulted in a significantly higher rate of major complications, especially distal embolisation. The other trial showed a significantly higher mean ankle brachial index (ABI) at two years in the PTA group (1.0) compared to the mean ABI in the PS group (0.91); mean difference (MD) 0.09 (95% confidence interval (CI) 0.04 to 0.14; P value = 0.001, analysis performed by review authors). However, at other time points there was no difference. We consider it unlikely that this difference is attributable to the study procedure, and also believe this difference may not be clinically relevant.

AUTHORS' CONCLUSIONS

There is insufficient evidence to assess the effects of PTA versus PS for stenotic and occlusive lesions of the iliac artery. From one study it appears that PS in iliac artery occlusions may result in lower distal embolisation rates. More studies are required to come to a firm conclusion.

Angioplasty for renovascular hypertension in 78 children

OBJECTIVES

To evaluate the outcome of percutaneous transluminal angioplasty (PTA) in children with renovascular hypertension (RVH) treated at a single centre over 29 years.

METHODS

A retrospective study of the medical charts of all children with RVH who underwent PTA between 1984 and 2012. The primary outcome measurement was blood pressure (BP) achieved after the procedure. The BP before the procedure was compared with that at last available follow-up, 6 (range 0.6-16) years after the initial procedure.

RESULTS

Seventy-eight children with median (range) age of 6.5 (0.5-17) years were studied. Twenty-three (29.5%) had an underlying syndrome, 35 (44.9%) children had bilateral renal artery stenosis (RAS), 18 (23%) intrarenal disease and 11(14%) showed bilateral RAS and intrarenal disease. Twenty (25.6%) children had mid-aortic syndrome and 14 (17.9%) cerebrovascular disease. One hundred and fourteen PTA procedures were carried out including 31 stent insertions. Following PTA, BP was improved in 49 (62.8%) children and of those 18 (23.1%) were cured. Children with involvement of only the main renal arteries showed improved BP control in 79.9% of the children with cure in 39.5%. BP was intentionally maintained above the 95th centile for age and height in four children with coexistent cerebrovascular disease. No change in BP was seen in 18 children despite observed technical success of the PTA, and in seven children due to technical failure of the procedure.

CONCLUSIONS

PTA provided a clinical benefit in 62.8% of children with RVH.

Why the definition of high risk has been inappropriately used in previous carotid trials

Carotid artery revascularization by endarterectomy is an effective means of stroke prevention in selected patients with carotid stenosis. With the development of endovascular techniques, carotid artery stenting (CAS) has been proposed as a viable alternative to carotid endarterectomy (CEA), particularly in patients considered at high risk for CEA. Guidelines have established criteria that outline these patients who are considered at "high risk" for complications after CEA, to whom CAS may provide benefit. The validity of these theoretical high-risk criteria, however, is yet unproven, and, as a consequence, there is no clear evidence suggesting that the risk with CAS is lower in these high-risk patients compared with CEA. This manuscript summarizes the role of "high risk" within recent trials and discusses why the optimal treatment for these patients with deemed high risk for surgery remains a matter of debate.

Carotid artery stenting: high-risk interventionist versus high-risk center

Carotid artery stenting (CAS) is a less invasive alternative to carotid endarterectomy (CEA) for the management of carotid artery stenosis. Although early multicenter randomized controlled trials reported inferior results for CAS compared with CEA, recent advances in technology and increasing CAS operator expertise have lead to improved results. As with any procedure, a high caseload translates into increased experience and better outcomes. This article discusses the current shortfalls of CAS, as well as the various options available to improve CAS results. The majority of studies suggest that there is an inverse relationship between caseload volume and CAS outcomes that defines high-risk interventionists and high-risk centers. Centralizing CAS procedures to high-volume centers is essential for optimization of CAS outcomes.

State-of-the-art treatment of common femoral artery disease

Atherosclerotic common femoral artery (CFA) disease is a well-known and frequent cause of symptomatic peripheral artery disease (PAD). Not so long ago, surgical treatment was considered the gold standard and the main treatment option. Therapeutic advances have, however, provided a wide and suitable armamentarium. These advances concern medical treatment and the direct treatment of lesions by open surgery or endovascular treatment. The aim of this manuscript was to summarize therapeutic updates and to describe the current endovascular and open surgical procedures used to treat common femoral artery disease.

Carotid artery: overview on current trials--selecting the low-risk patient

The ultimate goal of carotid stenosis treatment is the long-term prevention of stroke. While a large number of studies focusing on patients with symptomatic carotid stenosis have been carried out, fewer data are available from trials on asymptomatic and low-risk patients. Currently existing information on the optimal management of these patients is inconclusive and contradictory. Our aim was to review previous major trials conducted on carotid disease with a main focus on asymptomatic patients with carotid stenosis. Efforts to present currently ongoing trials involving asymptomatic carotid patients, to survey recent studies determining patients' risk for future stroke or periprocedural events, as well as to summarize data on promising structural and functional variables and biomarkers predicting future stroke risk have been made.

The role of perioperative antiplatelet therapy and platelet reactivity testing in carotid revascularization: overview of the evidence

Antiplatelet therapy has reduced the incidence of thromboembolic events for patients undergoing carotid revascularization. However, the platelet inhibitory effect of aspirin and clopidogrel, the most commonly used P2Y12 receptor inhibitors, is variable among patients. Patients displaying high platelet reactivity despite aspirin or clopidogrel treatment are at higher risk for thromboembolic events during and after carotid revascularization. In order to reduce the incidence of high platelet reactivity, more potent P2Y12 receptor inhibitors as prasugrel are used. However, this strategy increases the risk of bleeding. As there is evidence of a therapeutic window for platelet inhibition, platelet function tests could be helpful for tailoring antiplatelet therapy based on the patient's thrombotic and bleeding risk. This evidence overview describes the most commonly used platelet inhibitors, platelet function tests and the current evidence for tailoring of antiplatelet therapy to patients undergoing carotid revascularization.

Safety and efficacy of carbon dioxide and intravascular ultrasound-guided stenting for renal artery stenosis in patients with chronic renal insufficiency

We evaluated the feasibility, safety, and mid-term outcomes of renal artery stenting using carbon dioxide (CO₂) digital subtraction angiography and intravascular ultrasound (IVUS) for patients with renal insufficiency and significant atherosclerotic renal artery stenosis (RAS). Eighteen consecutive patients with chronic renal insufficiency underwent renal artery stenting under the guidance of CO₂ angiography and IVUS without contrast media. Renal function and blood pressure were assessed pre- and postintervention. A total of 27 de novo RAS in 18 patients (15 males; mean age: 72 ± 9 years) with renal insufficiency were treated by renal artery stenting with the combined use of the CO₂ angiography and IVUS without any procedural complications. Although the mean serum creatinine concentration preprocedure and 6 months after treatment did not change (2.7 ± 1.0-2.4 ± 1.1 mg/dL), blood pressure significantly decreased 6 months after stenting (158 ± 10-147 ± 11 mm Hg, P < .01).

Carotid endarterectomy versus stenting: Does the flow really change? An Echo-Color-Doppler analysis

To assess potential hemodynamic differences after carotid endarterectomy (CEA) and carotid artery stenting (CAS) and their eventual impact on clinical management. Between July 2012 and October 2013 two groups of 30 patients each referred for CEA or CAS were prospectively enrolled in two tertiary hospital care centers. Pre-procedural imaging assessment of carotid artery disease was performed with Echo-Color-Doppler (ECD) and computed tomography angiography (CTA). ECD was repeated within 24 h and 1, 6 and 12 months after surgical/endovascular procedures. Peak systolic velocity (PSV) and end diastolic velocity (EDV) were assessed at two standard sites: common carotid artery (CCA) and distal internal carotid artery (ICA). Twenty-four hours ECD findings highly differ between the two populations. CCA PSV in the CEA and CAS groups was respectively 44.88 ± 9.16 and 69.20 ± 20.04 cm/s (p = 0.002); CCA EDV was 16.11 ± 2.29 and 19.13 ± 6.42 cm/s (p = 0.065); ICA PSV was 46.11 ± 7.9 and 94.02 ± 57.7 cm/s (p = 0.0012); ICA EDV was 20.22 ± 4.33 and 30.47 ± 18.33 cm/s (p = 0.025). One month, 6 months and 1 year findings confirmed the different trend in the two cohorts; in particular, at 1 year: CCA PSV was 50.94 ± 12.44 and 60.59 ± 26.84 cm/s (p = 0.181); CCA EDV was 17.11 ± 3.46 and 19 ± 16.35 cm/s (p = 0.634); ICA PSV was 51.66 ± 10.1 and 70.86 ± 20.64 cm/s (p = 0.014); ICA EDV was 25.05 ± 8.65 and 32.66 ± 13 cm/s (p = 0.0609). ECD follow-up of patients undergone CEA or CAS may play a critical role in the clinical management. Strict surveillance of blood flow velocities allows reducing false positive re-stenosis diagnosis and choosing the best anti-aggregation therapies. Within the first month CEA patients benefit from a lower risk condition in comparison with CAS patients, due to a significantly faster PSV drop; moreover, long-term CCA PSV after CEA could be used as a surrogate marker of neointima formation.

Treatment of significant carotid artery stenosis in 1824 patients

AIM

We report our experience of thirteen years of treatment of significant carotid artery stenosis.

METHODS

Data of all consecutive patients who came to our Division for a significant carotid artery stenosis from January 1999 to January 2012 were collected about patients' demographic, cardiovascular risk factors, neurological symptoms and treatment (carotid endarterectomy, carotid artery stenting or best medical therapy). Retrospective review was performed and the occurrence of death, major cerebrovascular events (major stroke, minor stroke) and myocardial infarction (MI) were recorded both at 30-day and at long-term. Analysis was performed among groups by means of JMP 5.1(®).

RESULTS

Of 1824 patients who were admitted to our Department for a significant carotid stenosis, 582 were unsuitable for surgery and underwent carotid artery stenting (CAS, Group A). Three hundred and seventy-three of them were symptomatic (64.1%). Carotid endarterectomy (CEA) was performed in 1030 patients (Group B), 741 (71.9%) of them were symptomatic. The remaining patients (Group C) were treated using best medical therapy (BMT). At 30-day CEA compared to CAS and BMT was associated with higher risk of MI (2.1% vs. 0.2%, and 0.4% respectively, P<0.05), most of all in asymptomatic patients. CEA had a higher risk of cranial nerve injuries than CAS (3.3% vs. 0%, P<0.001). Both risk of death and major neurological complications were similar among the three groups in both symptomatic and asymptomatic patients. At long-term, risk of stroke after CEA was similar to that after CAS, both for symptomatic and asymptomatic patients, while risk of 1-year stroke in Group C was higher than in Group A (P<0.001) and in Group B (P<0.001), for both symptomatic and asymptomatic patients. Risk of long-term MI was similar among the three groups. Mortality at long term in symptomatic patients was higher after CAS than after CEA (P=0.001). Also long-term mortality in Group C was higher than in Group A and B (both P<0.001) but only for asymptomatic patients. A procedure that lasted for more than 60 minutes, patients who had no prior Magnetic Resonance Angiography (MRA) or Computed Tomographic Angiography (CTA) study of the aortic arch were independent risk factors for major neurological complications after CAS. Symptomatic patients were likely to have more major neurological complications in the long term if they were treated with BMT only.

CONCLUSION

In our experience, CAS offered a valid alternative for both symptomatic and asymptomatic patients who were poor candidates for CEA, with results that compared favourably to those of CEA both at 30-day and at long-term. Patients who couldn't be operated on neither with CAS nor with CEA had a lower risk of MI at 30-day but a higher risk of stroke during the first year, especially if they had previously experienced neurological symptoms.

Twelve-month experience with the GORE® TIGRIS® Vascular Stent in the superficial femoral and popliteal arteries

AIM

The aim of this paper was to report the continued mid-term follow-up of the first patients world-wide treated with the GORE(®) TIGRIS(®) Vascular Stent, a dual component stent consisting of a nitinol wire frame combined with a fluoropolymer-interconnecting structure.

METHODS

From December 2011 until November 2012, 32 consecutive patients (20 men, mean age 72.8 years) with 40 atherosclerotic femoropopliteal lesions (5% occlusions) underwent angioplasty and implantation of a GORE(®) TIGRIS(®) Vascular Stent. The patients were scheduled for follow-up at 3, 6 and 12 months after stent implantation for duplex ultrasound and assessment of Rutherford-Becker class (RBC) and Ankle-Brachial Index (ABI). Here we report the completed 6-month follow-up and, for the first time, a 12-month follow-up.

RESULTS

The median follow-up was 418 days. During the 12-month follow-up 4 patients died. Restenosis or reocclusion of the stent in this time period was observed in 5 lesions (12.5%), resulting in a cumulative primary patency rate of 85.5±6.0%. The ABI increased pre-interventionally from 0.65±0.18 to 0.91±0.18 (P<0.0001) at the 12-month visit. The median RBC improved from 3 to 1 (P<0.0001). No stent thrombosis related to discontinuation of dual antiplatelet therapy 4 weeks after the index procedure was observed.

CONCLUSION

The mid-term follow-up of the dual component GORE(®) TIGRIS(®) Vascular Stent showed promising results with high 12-month primary patency rates after femoropopliteal endovascular interventions. These first clinical data are very promising compared to other stent concepts in the superficial femoral and popliteal artery.