Carotid stenting versus endarterectomy for the treatment of carotid artery stenosis: Contemporary results from a large single center study.

OBJECTIVE: To compare the complication rates associated with carotid endarterectomy (CEA) versus carotid artery stenting (CAS). BACKGROUND: Carotid stenosis is a well-known cause of stroke and increased mortality. The safety of carotid revascularization may be related to symptom status, medical comorbidities, use of embolic protection devices, as well as operator experience and these factors may vary across patient populations within a single operating center. METHODS: We retrospectively analyzed patients with carotid artery stenosis admitted to our hospital for carotid revascularization between January 1, 2007 and December 1, 2013. The primary end point was a composite endpoint of periprocedural death, stroke, and myocardial infarction (MI). RESULTS: Of the 718 patients admitted for carotid revascularization 525 (73.1%) underwent CEA and 193 (26.9%) underwent CAS. Both groups demonstrated similar rates of the composite endpoint, MI, and death; the stenting group demonstrated a higher rate of stroke (4.2% vs. 1.3%; P = 0.020). Adjusting for baseline medical comorbidities and symptom status mitigated this difference (P = 0.091 and 0.113, respectively). When stratified by department performing CAS, there was a significant difference in the occurrence of stroke (P = 0.033), which likewise disappeared in the multivariate regression analysis. CONCLUSION: The risk of the composite endpoint did not differ significantly between those undergoing CAS versus CEA. The stenting group demonstrated a higher rate of periprocedural stroke, which was also apparent when patients were stratified by stenting department. These differences were likely driven by variation in baseline medical comorbidities and symptom status. © 2016 Wiley Periodicals, Inc.

Dysautonomic responses during percutaneous carotid intervention: principles of physiology and management.

Percutaneous carotid artery stenting (CAS) has emerged as a less invasive alternative to carotid endarterectomy for the treatment of carotid atherosclerotic disease. The main risk of CAS is the occurrence of neuro-vascular complications; however, carotid artery stenting-related dysautonomia (CAS-D) (hypertension, hypotension, and bradycardia) is the most frequently reported problem occurring in the periprocedural period. Alterations in autonomic homeostasis result from baroreceptor stimulation, which occurs particularly at the time of balloon inflation in the region of the carotid sinus. The response can be profound enough to induce asystole or even complete cessation of postganglionic sympathetic nerve activity. Frequency and factors predisposing a patient to CAS-D have been investigated in several studies; however, there are significant discrepancies in results among reports. Lack of consistent findings may arise from using different methods and definitions, as well as other factors discussed in detail in this review. Furthermore, a correlation of CAS-D with short and long-term outcomes has been investigated only in small and mostly retrospective studies, explaining why its prognostic significance remains uncertain. In this manuscript, we have focused on risk factors, pathophysiology and management of periprocedural autonomic dysfunction. As there is no standardized approach to the treatment of CAS-D, we present an algorithm for the periprocedural management of patients undergoing CAS. The proposed algorithm was developed based on our procedural experience as well as data from the available literature. The Yale Algorithm was successfully implemented at our institution and we are currently collecting data for short- and long-term safety. © 2014 Wiley Periodicals, Inc.

Management of symptomatic carotid disease in 2014.

Extracranial carotid artery stenosis accounts for up to 12 % of stroke, the third leading cause of death in industrialized nations. Carotid stenoses leading to transient or permanent neurologic or retinal symptoms within the preceding 6 months are deemed symptomatic and require prompt noninvasive evaluation and treatment. Preventive medical therapy is standard for symptomatic carotid stenosis and continues to evolve. Landmark trials have proven carotid endarterectomy (CEA) superior to medical therapy for stroke prevention in symptomatic lesions. Modern investigations have proven carotid artery stenting (CAS) non-inferior to CEA, and the strength of the combined data has led to a class I recommendation for CEA or CAS in patients with high grade symptomatic carotid stenosis, provided the risk of perioperative events is acceptable. Evidence-based modern management of symptomatic carotid stenosis is reviewed here.

Carotid stent deformation: sonographic findings and CT correlation.

Carotid artery dissection is a rare but potentially serious complication of endovascular procedures in the carotid arteries. Stent deformation or incomplete expansion may occur following endovascular repair of an iatrogenic carotid artery dissection and may mimic stent fracture. We report an unusual case of deformation of a common carotid artery open cell design stent following endovascular repair of an iatrogenic dissection, which resulted in persistent blood flow between the stent and the wall of the common carotid artery. Sonographic features are described and correlation with intravascular ultrasound and CT is provided.

Renal sympathetic denervation in the treatment of resistant hypertension.

Arterial hypertension (HTN) is a major health problem worldwide. Treatment-resistant hypertension (trHTN) is defined as the failure to achieve target blood pressure despite the concomitant use of maximally tolerated doses of three different antihypertensive medications, including a diuretic. trHTN is associated with considerable morbidity and mortality. Renal sympathetic denervation (RDn) is available and implemented abroad as a strategy for the treatment of trHTN and is currently under clinical investigation in the United States. Selective renal sympathectomy via an endovascular approach effectively decreases renal sympathetic nerve hyperactivity leading to a decrease in blood pressure. The Symplicity catheter, currently under investigation in the United States, is a 6-French compatible system advanced under fluoroscopic guidance via percutaneous access of the common femoral artery to the distal lumen of each of the main renal arteries. Radiofrequency (RF) energy is then applied to the endoluminal surface of the renal arteries via an electrode located at the tip of the catheter. Two clinical trials (Symplicity HTN 1 and Symplicity HTN 2) have shown the efficacy of RDn with a post-procedure decline of 27/17 mmHg at 12 months and 32/12 mmHg at 6 months, respectively, with few minor adverse events. Symplicity HTN-3 study is a, multi-center, prospective, single-blind, randomized, controlled study currently under way and will provide further insights about the safety and efficacy of renal denervation in patients with trHTN.

An evidence-based review of the impact of periprocedural myocardial infarction in carotid revascularization.

Landmark trials comparing carotid endarterectomy (CEA) with medical therapy in patients with symptomatic or asymptomatic atherosclerotic stenosis of extracranial carotid arteries have favored carotid revascularization. Carotid artery stenting (CAS) has emerged as a minimally invasive option for revascularization of carotid artery stenoses and has been shown to be noninferior to CEA, regardless of patient symptom status. Debate continues regarding the importance of periprocedural myocardial infarction (PMI) as an endpoint in carotid revascularization trials. Recent randomized comparisons of CEA and CAS pre-specify PMI as an endpoint. Understanding PMI in CEA and CAS, the need for routine biomarker assessment surrounding both revascularization strategies, the effect of PMI on long-term morbidity and mortality, and the groups most at risk for PMI are of critical importance when choosing a carotid revascularization strategy for symptomatic and asymptomatic patients, since decreasing the incidence of PMI will make revascularization safer. This review examines available data regarding the relevance of PMI in vascular and carotid-specific outcomes.

Carotid revascularization: a systematic review of the evidence.

OBJECTIVE AND BACKGROUND: The aim of this study is to provide an evidence-based review of the periprocedural safety and long-term effectiveness of carotid artery stenting (CAS) compared to carotid endarterectomy (CEA), with particular attention paid to the use of embolic protection devices and patients at high risk for CEA. METHODS: Electronic databases (Ovid Medline, Cochrane central register of controlled trials, Pubmed, and Embase) were searched to identify: (1) randomized controlled trials (RCT) comparing outcomes of CEA and CAS, and (2) prospective clinical trials assessing the safety of CAS in patients at high surgical risk. Pooled incidence rates and one-sided 95% confidence interval for the periprocedural and long-term composite end-point of stroke, myocardial infarction, or death among high surgical risk patients were generated and compared to objective performance criteria (OPC) reported by previous trials. RESULTS: Six RCTs and 14 prospective clinical trials met our search criteria. Selected RCTs showed inconsistency in reported periprocedural and long-term outcome rates. Pooled incidence rates of the periprocedural and long-term composite end-point of stroke, myocardial infarction or death in high surgical risk candidates were 5.59% and 7.92%, respectively. These results were noninferior to selected OPCs (P-value <0.001). CONCLUSIONS: CAS represents a safe and effective stroke prevention strategy in high surgical risk patients when compared with CEA. The inconsistent results from the RCTs and the improved outcomes in the prospective clinical trials are likely related to variability in operator experience, use of embolic protection devices, and patient selection strategies.

Recovery of left ventricular function after percutaneous revascularization of a left main chronic total occlusion.

Surgical revascularization of left main and/or three-vessel coronary artery disease (CAD) is associated with improved survival in patients with left ventricular dysfunction when compared to medical therapy and can result in improved left ventricular ejection fraction (LVEF) [1]. Multivessel percutaneous coronary intervention (PCI) is equivalent to surgery regarding short and intermediate term mortality, and left main PCI has emerged as a safe and effective alternate to surgical revascularization [2]. However, outcomes of unprotected left main PCI in patients with severely depressed LVEF have not been examined. We report a patient with left main chronic total occlusion, multivessel CAD, and dilated cardiomyopathy, in whom complete revascularization via PCI resulted in decreased left ventricular size and improved LVEF.

Computer-assisted detection of tardus parvus waveforms on Doppler ultrasound.

OBJECTIVE: To determine if a novel computer-generated metric, effective acceleration time, improves accuracy for detecting tardus parvus waveforms on spectral Doppler ultrasound. METHODS: Patients with echocardiography-confirmed aortic valve stenosis (n = 132; 60 mild, 44 moderate, 28 severe) and matched controls (n = 48) who underwent carotid Doppler ultrasound were identified through an imaging database search at a single medical center. A custom-built spectral analysis computer program generated effective acceleration time values for spectral Doppler waveforms in the carotid arteries and a receiver operating characteristic analysis was performed to determine the optimal median effective acceleration time cutoff value to detect tardus parvus waveforms. Two radiologists, blinded to subject disease status, reviewed and rated all carotid sonograms for presence of tardus parvus waveforms. Inter-rater variability was measured, and the accuracy of aortic valve stenosis detection with and without use of the effective acceleration time cutoff was calculated. RESULTS: Receiver operating characteristic analysis revealed an optimal effective acceleration time cutoff of ≥ 48 ms with a corresponding area under the curve of 0.77 (95% CI: 0.70-0.84). Use of the effAT cutoff demonstrated an accuracy of 74%. Accuracy of visual waveform interpretation by raters ranged from 43% to 61%. Inter-rater agreement in detection of tardus parvus waveforms was 76% (136/180 cases, K = 0.44, p < 0.001). CONCLUSIONS: Detection of tardus parvus waveforms through visual interpretation of spectral Doppler waveform morphology is limited by low accuracy and moderate inter-rater variability. Use of a computer-generated median effective acceleration time cutoff value markedly improves diagnostic accuracy and avoids observer variability.

Readmissions after carotid artery revascularization in the Medicare population.

BACKGROUND: In appropriately selected patients with severe carotid stenosis, carotid revascularization reduces ischemic stroke. Prior clinical research has focused on the efficacy and safety of carotid revascularization, but few investigators have considered readmission as a clinically important outcome. OBJECTIVES: The aims of this study were to examine frequency, timing, and diagnoses of 30-day readmission following carotid revascularization; to assess differences in 30-day readmission between patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS); to describe hospital variation in risk-standardized readmission rates (RSRR); and to examine whether hospital variation in the choice of procedure (CEA vs. CAS) is associated with differences in RSRRs. METHODS: We used Medicare fee-for-service administrative claims data to identify acute care hospitalizations for CEA and CAS from 2009 to 2011. We calculated crude 30-day all-cause hospital readmissions following carotid revascularization. To assess differences in readmission after CAS compared with CEA, we used Kaplan-Meier survival curves and fitted mixed-effects logistic regression. We estimated hospital RSRRs using hierarchical generalized logistic regression. We stratified hospitals into 5 groups by their proportional CAS use and compared hospital group median RSRRs. RESULTS: Of 180,059 revascularizations from 2,287 hospitals, CEA and CAS were performed in 81.5% and 18.5% of cases, respectively. The unadjusted 30-day readmission rate following carotid revascularization was 9.6%. Readmission risk after CAS was greater than that after CEA. There was modest hospital-level variation in 30-day RSRRs (median: 9.5%; range 7.5% to 12.5%). Variation in proportional use of CAS was not associated with differences in hospital RSRR (range of median RSRR across hospital groups 9.49% to 9.55%; p = 0.771). CONCLUSIONS: Almost 10% of Medicare patients undergoing carotid revascularization were readmitted within 30 days of discharge. Compared with CEA, CAS was associated with a greater readmission risk. However, hospitals' RSRR did not differ by their proportional CAS use.

Critical evaluation of stents in the peripheral arterial disease of the superficial femoral artery - focus on the paclitaxel eluting stent.

The endovascular management of obstructive disease of the superficial femoral artery (SFA) is challenging due to unique anatomical and biomechanical forces. Obstructive lesions of the SFA make up the largest proportion of lesions leading to symptomatic peripheral arterial disease. Accordingly, endovascular treatment of SFA disease is becoming increasingly common and, in many cases, is the preferred initial therapy. The use of self-expanding nitinol stents have proven superior to percutaneous transluminal balloon angioplasty in the treatment of intermediate length SFA stenosis. However, achieving durable results, as well as attaining adequate therapy for long occlusions typically seen in clinical practice, remains problematic. Newer technologies, such as paclitaxel eluting stents, seem promising in improving outcomes.

The link between vasculogenic erectile dysfunction, coronary artery disease, and peripheral artery disease: role of metabolic factors and endovascular therapy.

Erectile dysfunction (ED) is estimated to affect 150 million people worldwide and may indicate diffuse systemic macrovascular disease. Endothelial dysfunction represents the probable pathophysiological link between vasculogenic ED, coronary artery disease (CAD), and peripheral artery disease (PAD), and the artery size hypothesis along with evidence-based research support ED as the incident clinical event. Given that many common risk factors for atherosclerosis, including smoking, diabetes mellitus, hyperlipidemia, and obesity are prevalent and causative in patients with ED, it is likely that metabolic factors play a crucial role in the link between the two disorders. The interplay of these factors provides a unifying physiological, endocrinological, and behavioral model for the association between ED, CAD, and PAD. Current therapy is unlikely to reverse the natural history of ED. Percutaneous revascularization may improve ED symptoms, and thereby quality of life, in a select group of patients. Large prospective studies are needed to define male pelvic arterial anatomy and thus enhance the utilization of internal pudendal angiography and revascularization. In this review, we provide an overview of normal erectile anatomy and physiology, the pathophysiology of ED, currently accepted diagnostic imaging modalities and treatments for ED, and recently investigated endovascular therapies for ED.