Rafal Motyl

Carotid artery stenting with patient- and lesion-tailored selection of the neuroprotection system and stent type: early and 5-year results from a prospective academic registry of 535 consecutive procedures (TARGET-CAS).

Purpose: To develop and prospectively evaluate the safety and efficacy of an algorithm for tailoring neuroprotection devices (NPD) and stent types to the patient/lesion in carotid artery stenting (CAS). Methods: From November 2002 to October 2007, 499 patients (360 men; mean age 65.2±8.4 years, range 36–88) were prospectively enrolled in a safety and efficacy study of tailored CAS using proximal (flow blockade or reversal) or distal (filters or occlusion) NPDs and closed- or open-cell self-expanding stents. Of the 535 lesions treated in the study, 175 (32.7%) were “high risk” by morphology. Half (50.1%) the patients were symptomatic. Results: A quarter (137, 25.6%) of the procedures were performed under proximal protection and the remainder (398, 74.4%) with distal NPDs; the direct stenting rate was 66.9%. High-risk lesions were treated predominantly with a proximal NPD and closed-cell stent (77.1% and 82.9%, respectively) and less frequently by direct stenting (37.1%, p<0.0001 versus non-high-risk lesions). The in-hospital death/stroke rate was 2.0% (95% CI 0.85% to 3.23%), and the death/major stroke rate was 0.7% (95% CI 0.02% to 1.48%). There were no myocardial infarctions, but there was 1 (0.2%) further death within 30 days. With the tailored approach, symptom status and high-risk lesion morphology were not risk factors for an adverse outcome after CAS; only age >75 years (p<0.001) was a predictor of short-term death. Long-term survival (95.4% at 1 and 88.3% at 5 years) was similar for symptomatic versus asymptomatic patients, direct stenting versus predilation, and closed-vs. open-cell stent design; only coronary artery disease adversely impacted survival (p=0.04). The rates of freedom from death/ipsilateral stroke were 94.9% at 1 year and 85.9% at 5 years. Conclusion: Tailored CAS is associated with a low complication rate and high long-term efficacy. CAS operators should have a practical knowledge of different NPDs, including at least one proximal type.

Assessment of Flow Changes in the Circle of Willis after Stenting for Severe Internal Carotid Artery Stenosis

Purpose: To assess flow velocities in the cerebral arteries after carotid artery stenting (CAS) in patients with unilateral versus bilateral lesions and analyze velocities in patients with neurological complications after CAS. Methods: Ninety-two patients (68 men; mean age 63.2±8.4 years, range 44–82) with internal carotid artery (ICA) stenoses were divided according to unilateral (group I, n=72) or bilateral (group II, n = 20) disease. Fifty age- and gender-matched patients without lesions in the extra- or intracranial arteries served as a control group. Transcranial color-coded Doppler ultrasound was performed prior to and within 24 hours after CAS in the test groups; systolic velocities were assessed ipsilateral (i) and contralateral (c) to the CAS site in the middle cerebral artery (MCA) and anterior cerebral artery (ACA). Results: Collateral flow via the anterior communicating artery (ACoA) was found in all group-II patients and 90% of group-I patients. After CAS, collateral flow through the ACoA ceased, and the velocity increased by 26% in the iMCA in group I compared to controls (p<0.001). In group II, iMCA flow increased by 30% (p<0.001) and flow via the ACoA (p<0.001) increased, resulting in normalization of cMCA velocities (p=0.928). In 89 (96.7%) subjects, CAS was uncomplicated. Hyperperfusion syndrome occurred in 2 (2.2%) patients, both with bilateral ICA stenoses; 1 (1.1%) transient ischemic attack was seen in a patient with unilateral disease. In the patients with hyperperfusion syndrome, the MCA velocities were 2.7- and 7.4-fold higher, respectively, versus before CAS and 2-fold higher than in controls. Conclusion: Uncomplicated CAS results in an iMCA velocity increase >25% compared to controls. MCA velocities in hyperperfusion syndrome were greatly increased versus before CAS and in controls.

Multimarker Approach in Discriminating Patients with Symptomatic and Asymptomatic Atherosclerotic Carotid Artery Stenosis

Background and Purpose Several circulating biomarkers have been implicated in carotid atherosclerotic plaque rupture and thrombosis; however, their clinical utility remains unknown. The aim of this study was to determine the role of a large biomarker panel in the discrimination of symptomatic (S) vs. asymptomatic (A/S) subjects in a contemporary population with carotid artery stenosis (CS). Methods Prospective sampling of circulating cytokines and blood lipids was performed in 300 unselected, consecutive patients with ≥50% CS, as assessed by duplex ultrasound (age 47-83 years; 110 with A/S and 190 with S) who were referred for potential CS revascularization. Results CS severity and pharmacotherapy did not differ between the A/S and S patients. The median values of total cholesterol, low-density lipoprotein cholesterol, and lipoprotein(a) did not differ, but high-density lipoprotein (HDL) cholesterol was significantly higher (p<0.001) and triglycerides were lower (p=0.03) in the A/S-CS group than in the S-CS group. Interleukin-6 (IL-6) and high-sensitivity C-reactive protein were higher (p=0.04 and p=0.07, respectively) in the S-CS group. Circulating visfatin, soluble CD 40 receptor ligand, soluble vascular cell adhesion molecule, leptin, adiponectin, IL-1β, IL-8, IL-18, monocyte chemoattractant protein-1, myeloperoxidase, matrix metalloproteinases-8, -9, and -10, and fibrinogen were similar, but tissue inhibitor of matrix metalloproteinases-1 (TIMP) was reduced in S-CS compared to A/S-CS (p=0.02). Nevertheless, incorporation of TIMP and IL-6 did not improve the HDL-cholesterol receiver operating characteristics for S-CS status prediction. S-CS status was unrelated to angiographic stenosis severity or plaque burden, as assessed by intravascular ultrasound (p=0.16 and p=0.67, respectively). Multivariate logistic regression analysis revealed low HDL-cholesterol to be the only independent predictor of CS symptoms, with an odds ratio of 1.81 (95% confidence interval=1.15-2.84, p=0.01) for HDL <1.00 mmol/L (first quartile) vs. >1.37 (third quartile). In S-CS, osteoprotegerin and lipoprotein-associated phospholipase A2 (Lp-PLA2) were elevated in those with recent vs. remote symptoms (p=0.01 and p=0.02, respectively). Conclusions In an all-comer CS population on contemporary pharmacotherapy, low HDL-cholesterol (but not other previously implicated or several novel circulating biomarkers) is an independent predictor of S-CS status. In addition, an increase in circulating osteoprotegerin and Lp-PLA2 may transiently indicate S transformation of the carotid atherosclerotic plaque.

Use of the Parodi Anti-Emboli System and Transient Subclavian Steal for Cerebral Protection during Emergent Vertebral Artery Recanalization

Purpose: To report the use of the Parodi Anti-Emboli System (PAES) for cerebral protection during emergent vertebral artery recanalization. Case Report: A 56-year-old chimney sweep was referred with recurrent episodes of vertigo and gait ataxia. Left vertebral artery (LVA) flow was barely detectable on duplex Doppler, and brain computed tomography revealed a small infarct in the posterior inferior cerebellar artery territory. Angiography showed subtotal ostial stenosis of the LVA with poor distal flow and possible thrombus. Due to a high risk of distal embolization with percutaneous treatment, anticoagulation was initiated, and the lesion was to be re-evaluated in 2 to 3 weeks. However, 2 days later, the patient developed severe, aggravating headache, gait and left-limb ataxia, horizontal nystagmus, and vomiting. Emergent angiography showed a total ostial LVA occlusion. The PAES was employed to elicit a temporary subclavian steal during percutaneous LVA recanalization, thus protecting the brain from embolization. The ostial LVA was successfully recanalized and stented, with immediate symptom cessation. Conclusions: The PAES can be successfully applied in the subclavian artery to prevent distal embolization during emergent vertebral artery recanalization. Since a significant proportion of vertebral strokes are embolic, PAES may play a novel role in the treatment of acute cerebellar stroke.

Predictors of Cerebral Reperfusion Injury After Carotid Stenting: The Role of Transcranial Color-Coded Doppler Ultrasonography

Purpose: To evaluate the possible role of transcranial color-coded Doppler ultrasonography (TCD) in predicting cerebral reperfusion injury (CRI) in patients undergoing carotid artery stenting (CAS) for internal carotid artery (ICA) stenosis. Methods: TCD was obtained in 210 patients (149 men; mean age 64.2±8.4 years, range 44–83) who underwent CAS for ICA stenosis averaging 86.7%±8.4%. Contralateral ICA occlusion or near occlusion (stenosis >90%) was present in 67 (31.9%) patients. TCD was performed before and 24 hours after CAS with assessment of peak systolic velocities (PSVs) in the ipsilateral middle cerebral artery (iMCA) and contralateral middle cerebral artery (cMCA). PSV ratios (PSVR) in the iMCA and cMCA were calculated from the PSVs before and after CAS. Results: CRI syndrome occurred in 3 (1.4%) patients (2 intracranial bleedings, 1 subarachnoid hemorrhage). The mean iMCA and cMCA PSVRs were 2.66±0.19 and 4.16±2.77, respectively, in CRI patients, while the PSVRs in CAS patients without neurological sequelae were 1.56±0.46 and 1.21±0.39, respectively (both p<0.001). The combination of iPSVR>2.4 and cPSVR>2.4 occurred in 4 patients with bilateral ICA disease; 3 (75%) of them developed CRI (100% sensitivity and 99% specificity for CRI prediction). The following independent CRI predictors were identified: combined iPSVR>2.4 and cPSVR>2.4 (RR 2.06, CI 1.89 to 2.24; p<0.001), high cMCA PSV after CAS (RR 1.23, CI 1.13 to 1.34; p<0.001), and contralateral ICA occlusion (RR 1.13, CI 1.03 to 1.23; p=0.007). Conclusion: TCD is an important tool in CRI risk evaluation. The combination of iPSVR>2.4 and cPSVR>2.4 is an independent CRI risk factor, along with contralateral ICA occlusion and high cMCA PSVs after CAS.

Safety of embolic protection device-assisted and unprotected intravascular ultrasound in evaluating carotid artery atherosclerotic lesions.

Summary Background Significant atherosclerotic stenosis of internal carotid artery (ICA) origin is common (5–10% at ≥60 years). Intravascular ultrasound (IVUS) enables high-resolution (120 μm) plaque imaging, and IVUS-elucidated features of the coronary plaque were recently shown to be associated with its symptomatic rupture/thrombosis risk. Safety of the significant carotid plaque IVUS imaging in a large unselected population is unknown. Material/Methods We prospectively evaluated the safety of embolic protection device (EPD)-assisted vs. unprotected ICA-IVUS in a series of consecutive subjects with ≥50% ICA stenosis referred for carotid artery stenting (CAS), including 104 asymptomatic (aS) and 187 symptomatic (S) subjects (age 47–83 y, 187 men). EPD use was optional for IVUS, but mandatory for CAS. Results Evaluation was performed of 107 ICAs (36.8%) without EPD and 184 with EPD. Lesions imaged under EPD were overall more severe (peak-systolic velocity 2.97±0.08 vs. 2.20±0.08m/s, end-diastolic velocity 1.0±0.04 vs. 0.7±0.03 m/s, stenosis severity of 85.7±0.5% vs. 77.7±0.6% by catheter angiography; mean ±SEM; p<0.01 for all comparisons) and more frequently S (50.0% vs. 34.6%, p=0.01). No ICA perforation or dissection, and no major stroke or death occurred. There was no IVUS-triggered cerebral embolization. In the procedures of (i) unprotected IVUS and no CAS, (ii) unprotected IVUS followed by CAS (filters – 39, flow reversal/blockade – 3), (iii) EPD-protected (filters – 135, flow reversal/blockade – 48) IVUS+CAS, TIA occurred in 1.5% vs. 4.8% vs. 2.7%, respectively, and minor stroke in 0% vs. 2.4% vs. 2.1%, respectively. EPD intolerance (on-filter ICA spasm or flow reversal/blockade intolerance) occurred in 9/225 (4.0%). IVUS increased the procedure duration by 7.27±0.19 min. Conclusions Carotid IVUS is safe and, for the less severe lesions in particular, it may not require mandatory EPD use. High-risk lesions can be safely evaluated with IVUS under flow reversal/blockade.

Flow reversal for proximal neuroprotection during endovascular management of critical symptomatic carotid artery stenosis coexisting with ipsilateral external carotid artery occlusion.

Purpose: To report the utility of proximal brain protection by flow reversal in endovascular management of critical internal carotid artery (ICA) stenosis coexisting with ipsilateral external carotid artery (iECA) occlusion. Case Report: Four patients with a symptomatic, critical ICA stenosis (in-stent restenosis in one) and iECA occlusion were admitted for carotid artery stenting (CAS). In all cases, the stenosis severity and high-risk lesion morphology precluded the use of filter protection. The “tailored” CAS algorithm indicated that a proximal anti-embolism system should be used to maximize the potential for effective neuroprotection. The flow reversal system, which consists of an independent guiding sheath balloon positioned in the common carotid artery (CCA) and an iECA balloon-wire, was employed, using the CCA balloon only. The system was well-tolerated, and the CAS procedures were uneventful. Conclusion: Due to a unique design with separate CCA and iECA balloons, the flow reversal system can be used for proximal neuroprotection during CAS in severe, symptomatic ICA lesions coexisting with iECA occlusion.

Treatment strategies in severe symptomatic carotid and coronary artery disease

Summary Coexistent carotid artery stenosis (CS) and multivessel coronary artery disease (CAD) is not infrequent. One in 5 patients with multivessel CAD has a severe CS, and CAD incidence reaches 80% in those referred for carotid revascularization. We reviewed treatment strategies for concomitant severe CS and CAD. We performed a literature search (MEDLINE) with terms including carotid artery stenting (CAS), coronary artery bypass grafting (CABG), carotid endarterectomy (CEA), stroke, and myocardial infarction (MI). The main therapeutic option for CS-CAD has been (simultaneous or staged) CEA-CABG. This, however, is associated with a high risk of MI (in those with CEA prior to CABG) or stroke (CABG prior to CEA), and the cumulative major adverse event rate (MAE – death, stroke or MI) reaches 10–12%. With increasing adoption of CAS, a sequential strategy of CAS followed by CABG has emerged. Registries (usually single-centre) indicate an MAE rate of ≈7% for CAS followed by CABG (frequently after >30 days, due to double antiplatelet therapy). Recently, 1-stage CAS-CABG has been introduced. This involves different antiplatelet regimens and, in some centers, preferred off-pump CABG, with a cumulative MAE of 1.4–4.5%. No randomized trial comparing different treatment strategies in CS-CAD has been conducted, and thus far reported series are prone to selection/reporting bias. In addition to the established surgical treatment (CEA-CABG, sequential/simultaneous), hybrid revascularization (CAS-CABG) is emerging as a viable therapeutic option. Larger, preferably multi-centre, studies are required before this can become widely applied.