Mid‐term outcome after carotid artery stenting depends on presence of coronary artery disease

BACKGROUND. Longer‐term outcome of patients following carotid artery revascularization depends predominantly on cardiac events rather than neurological events.

AIM. To assess the longer‐term outcomes of patients with known coronary artery morphology undergoing carotid artery stenting.

METHOD. In a prospective observational study including 549 consecutive patients undergoing carotid artery stenting, a coronary angiography was performed in a single session unless a recent angiogram was available. Following the intervention, patients were followed prospectively to determine neurological events as well as major adverse coronary events (MACE) during long‐term follow‐up.

RESULTS. Coronary artery disease was present in 378 patients including 92 patients without current significant stenosis. The MACE rate was 6.4% in patients without coronary artery disease compared to 28.3% in patients with coronary artery disease (P<0.00001). Cardiac and all‐cause mortality were statistically significantly higher in patients with a significant coronary stenosis than in patients without coronary artery disease (P<0.001 and P<0.01). Cardiac mortality and all‐cause mortality were 2.3% and 7.6% in patients without coronary artery disease (patient group I), 7.6% and 13.0% in patients with coronary artery disease but no current significant stenosis (patient group II), and 10.5% and 16.1% in patients with significant coronary stenosis (patient group III). Neurological events, however, were distributed equally among the three patient groups.

CONCLUSIONS<1/emph>. In the longer term, outcomes in patients undergoing carotid artery stenting depend on concomitant coronary artery disease rather than neurological events, cardiac mortality and even all‐cause mortality depending on a significant coronary artery stenosis.     

Carotid artery interventions for restenosis after prior stenting: is it different from interventions of de novo lesions? Results from the carotid artery stent (CAS)—registry of the Arbeitsgemeinschaft Leitende Kardiologische Krankenhausärzte (ALKK)

Objective

To compare characteristics and outcome of patients with re-stenoses after prior carotid artery stenting (CAS) treated with repeat carotid interventions (Re-CI) with CAS for de novo lesions.

Background

The treatment of re-stenosis is a major problem in vascular interventions. Patients with re-stenoses after prior CAS treated with Re-CI are not well defined.

Methods

We analyzed data from the prospective ALKK CAS Registry.

Results

Out of 3,817 CAS procedures 95 were intended in 93 patients (2.5%) for a restenosis after prior CAS and 3,722 CAS in 3,655 patients (97.5%) for a de novo stenosis. There was no difference in age (p = 0.302) or distribution of gender (p = 0.545) between the two groups. Patients treated for a restenosis after CAS were less likely to be treated for a symptomatic lesion (22.7 vs. 40.1%, p = 0.001). Coronary heart disease (p = 0.017), peripheral arterial disease (p < 0.001) as well as diabetes mellitus (p = 0.004) were more prevalent in the restenosis group. Lesions were less complicated in restenosis patients, with less ulcers (7.4 vs. 19.9%, p = 0.003) and less severe calcifications (7.4 vs. 23.6%, p < 0.001). The intended interventions were more often not performed in the Re-CI group (9.5 vs. 3.3%; p = 0.001). In-hospital, the stroke or death rate was 0% in the Re-CI group as compared to 3.1% in the de novo group (p = 0.115).

Conclusions

Patients treated with Re-CI for repeat stenoses after prior CAS represent 2.5% of current CAS patients. Although representing a subgroup with more concomitant diseases, Re-CI seems to be associated with lower event rates as compared to CAS for de novo lesions.     

What is the learning curve for carotid artery stenting with neuroprotection? Analysis of 200 consecutive cases at an academic institution

Carotid artery stenting (CAS) has emerged as an acceptable treatment alternative in high-risk patients with carotid stenosis. This study assessed the effect of the learning curve on treatment complications and clinical outcome of CAS. Clinical variables and treatment outcomes of 200 consecutive CAS procedures in 182 patients (mean age, 72 years) with carotid stenosis of 70% or greater during a 40-month period were analyzed. Technical success, periprocedural complications, and treatment outcomes were compared in four sequential groups (group I, II, III, and IV) of 50 consecutive interventions. Treatment indications and relevant risk factors were similar among the four groups. The overall technical success was 98%, and the combined 30-day stroke and death rates was 2.5%. An increase in the technical success rate was noted in the latter three groups compared with group I (P < .05). Total procedural time and contrast volume were significantly higher in group I compared with the latter three groups (P < .05). The intraoperative anticoagulation regimen was changed from an intravenous heparin combination to bivalirudin after the first 54 cases, resulting in reduced bleeding complications in groups III and IV (P = .03) compared with group I. The 30-day stroke and death rate in groups I and II was 8% and 2%, which was reduced significantly to 0% in groups III and IV (P < .05). A Cox regression model identified procedural volume (P = .03) as a predictor of a reduced complication rate. Carotid artery stenting with neuroprotection can provide excellent treatment outcome. Our experience demonstrates a procedural-associated learning curve, as evidenced by the reduced procedural-related complications, fluoroscopic time, and contrast volume that occurred with an increase in physician experience. The procedural success is also enhanced partly by endovascular device refinement and improved anticoagulation regimen. Successful outcome of CAS can be achieved once physicians overcome the initial procedural-related learning curve.     

Why to operate on the carotid artery?

AIM, METHODS, PATIENTS: In a prospective interdisciplinary study of 468 carotid artery stenoses we compared the ultrasound plaque morphology with the histological diagnosis. RESULTS: For detection of soft plaques and hard plaques by preoperative ultrasound examination we found a sensitivity of 80%. The accuracy for the estimation of the degree of the stenosis was 98%. In case of stroke in progression and completed stroke we found ulcerations by histological examination in 72%. By ultra-sound these ulcerations were detected only in 53%. We found a significant higher figure for TIA and stroke in soft plaque patients than in asymptomatic stage, in which hard plaque formation was seen more often. CONSEQUENCES: Patients with a soft plaque seem to have a higher risk of a postoperative permanent neurological deficit. However, the dangerous plaque formation with thrombosis or ulceration was not be detected with appropriate accuracy. Therefore the risk of embolisation cannot be predicted sufficiently by means of duplex scanning. This would be extremely important for the indication for stenting in this area. The number of HITS (high intensity transient signals) is 8 to 20 times higher in carotid stenting.     

Is flow in the common carotid artery fully developed?

The assumption of fully developed or axisymmetric velocity profiles in the common carotid artery (CCA) underlies the straightforward estimation of CCA blood flow rates or wall shear stresses (WSS) from limited velocity data, such as spectral peak velocities acquired using Doppler ultrasound. Using an automated velocity profile classifier developed for this study, we characterized the shape of the CCA velocity profile from cine phase contrast magnetic resonance images acquired as part of an Atherosclerosis Risk in Communities (ARIC) ancillary study, here focusing on 45 participants imaged twice as part of a repeatability protocol. When averaged over the cardiac cycle, roughly 60% of the velocity profiles were classified as skewed, with over half of these exhibiting the crescent shape characteristic of strong Dean-type flow in a curved tube. During early diastole, roughly 80% of the velocity profiles were skewed. In most cases the degree and orientation of skewing were reproduced in the repeat scan, indicating the persistence of these flow features. Fully developed flow thus appears to be the exception rather than the rule in the nominally straight CCA. Implications of this for flow rate and WSS estimation, and perhaps the development and progression of carotid atherosclerosis, warrant further investigation.     

Hyperhomocysteinemia and the risk of restenosis after coronary artery stenting: fact or fiction?

The incidence of restenosis after coronary artery stent placement is approximately 38%. An interesting view has been stipulated: that hyperhomocysteinemia may be partly responsible for in-stent restenosis. Epidemiologic evidence exists that is persuasive in suggesting that individuals with occlusive vascular disease have a higher blood homocysteine concentration than control subjects. Thus, elevated plasma levels of homocysteine have been implicated as a risk factor for coronary artery disease. The composition of the current clinical knowledge on the question of whether hyperhomocysteinemia is a significant factor for restenosis of coronary artery stents consists of several trials with different approaches, objectives and outcomes. However, the current studies that have been published in the peer-reviewed medical literature have not reached a consensus as to whether an elevated plasma level of homocysteine is an independent risk factor responsible for restenosis following stent implantation. Our current knowledge as to the place of plasma homocysteine levels in the development of in-stent restenosis seems incomplete, and in the realm of homocysteine and restenosis of stents, there are plenty of questions that still remain to be answered.     

What are the skills that prepare vascular surgeons for carotid stenting?

Although it has been clearly established that in certain groups of patients, such as in patients with symptomatic high-grade carotid stenosis and in selected asymptomatic patients with high-grade stenosis, carotid endarterectomy offers significant protection from stroke compared with medical therapy, the role of carotid stenting in this patients versus carotid endarterectomy is undergoing a rapid evolution. The definitive evidence awaits the results of ongoing prospective, randomized trials such as CREST and others, but it is clear that carotid stenting will increasingly occupy a significant role in the therapy of carotid bifurcation disease. In that context, vascular surgeons, traditionally the experts on the management of this condition, face the specter of other disciplines intervening in its treatment. In addition, if vascular surgeons do not acquire the skills and the expertise necessary to perform carotid stenting, it is self-evident that they run the risk of being spectators rather retaining the mantle of expert in the management of carotid bifurcation disease. As such, it is the duty of vascular surgeons to acquire the skills with which to retain their rightful place in its management and treatment. The purpose of this article is to describe the skills necessary to become competent in the endovascular management of carotid disease, offer some thoughts and strategy by which one can gain experience and develop an armamentarium of skills necessary to perform carotid stenting, and offer a comprehensive array of options of management and treatment to the patient with carotid disease.     

Revascularization of myocardium: coronary artery bypass grafting or stenting?

The aim of the study was comparative analysis of long-term results (5 years) after coronary angioplasty and stenting (CAS) and coronary artery bypass grafting (CABG). The results of the treatment of 1100 patients with coronary heart disease, operated since 1999 to 2006 year, were analyzed. 720 (65.5%) patients had undergone CABG (group 1), 226 (20.5%) had had an implantation of stents with pharmaceutical coverage (group 2) 154 (14%) had been implanted with stents without pharmaceutical coverage (group 3). Clinical examination as a rule had occurred before operation, 29-30 days after operation and in every 12 months after discharge from the hospital. Five years survival rate in group of CABG patients was 85.9% and in groups of CAS patients it was 84.1% and 70.8% respectively. Restenosis occurred more frequently in CAS patients: in group 2 in 18.1% patients, in group 3--in 70.1% In group of CABG patients acute myocardial infarction occurred in 11.9% cases to the end of 5th year, in groups 2 and 3 this index was 10.9% and 18.3% respectively. Angina pectoris was absent in 1 year in CABG patients (62%) than in CAS patients (46.7% and 24.3% in groups 2 and 3 respectively; p < 0.05). Comparing results of CAS with use of stents with and without pharmaceutical coverage, the best clinical result was in the group with implanted stents of new generation. Relatively better clinical effect during 5 years occurred in CABG patients.     

Hypertrophy of intima media of the carotid artery due to L-dopa therapy in Parkinson’s disease

Introduction Recent studies have shown that L-dopa therapy used in patients with Parkinson’s disease might cause thickening of the carotid artery intima media. It is known that intima-media thickening is a sign of systemic atherosclerosis. The purpose of this study was to clarify the correlation between L-dopa medication and carotid artery intima-media thickness (IMT) in patients with Parkinson’s disease. Methods Twenty-five patients with Parkinson’s disease who used L-dopa (LD+) and 17 patients who did not use L-dopa (LD-) treatment were included in this study. Colour Doppler with B-mode carotid ultrasonography was performed. The Hoehn-Yahr scale was used for staging of Parkinson’s disease in an ‘on’ state. The Student t test was used for statistical analysis. Results The IMT of the left internal carotid and external carotid arteries were found to be thicker in patients treated with L-dopa. The mean IMT of the left internal carotid artery was 0.937±0.391 mm in the LD+ group and 0.677±0.138 mm in the LD-group (P=0.013). The mean IMT of the left external carotid artery was 0.956±0.531 mm in the LD+ group and 0.646±0.18 mm in the LD-group (P=0.037). Conclusion The IMT of the carotid artery was found to be thicker in patients who were treated with L-dopa. In conclusion, patients treated with L-dopa appear to be at a higher risk of thickening of the intima media of the carotid artery.     

What is the latest in inventory for carotid stenting and cerebral protection?

Carotid angioplasty is fast being incorporated into the treatment options for patients with carotid occlusive disease. The results of the SAPPHIRE and ARCHER trials have demonstrated that carotid angioplasty and stenting with the use of cerebral protection devices is not inferior to open surgical endarterectomy in high-risk patients. The limiting step for percutaneous carotid interventions was the potential for cerebral embolization during the intervention. However, the ready availability of several embolic protection devices has placed this technology into the hands of many endovascular specialists. A brief outline of the basic inventory necessary for a carotid stent program is presented.     

Carotid stenting or surgical carotid endarterectomy to prevent strokes?

Stroke has a high incidence and is associated with a dramatic degree of morbidity and mortality. Carotid stenosis is responsible for approximately 20% of strokes in all patient populations, and is especially prevalent in elderly patients. Therapies to decrease the risk of stroke are urgently warranted. The first established therapy was surgical endarterectomy. Over the last few years, however, carotid artery stenting has evolved as a less invasive approach. Hitherto, the paper under evaluation (the North American Carotid Revascularization Endarterectomy versus Stenting Trial [CREST]) is the largest and most important study comparing these two treatment modalities. The study demonstrates comparable effectiveness for carotid stenting and carotid artertectomy to reduce the risk for future strokes.