Ebook Carotid artery stenting - Current practice and techniques: Part 2

(BQ) Part 2 book “Carotid artery stenting - Current practice and techniques” has contents: Intravascular filter anti-embolization systems, restenosis following carotid artery stenting, limitations of current equipment and the future carotid artery stenting device, clinical investigations and protocols,… and other contents.

15 CAROTID ARTERY STENTING WITH THE DISTAL OCCLUSION ANTIEMBOLIZATION SYSTEM MICHEL HENRY ANTONIOS POLYDOROU ISABELLE HENRY M I C H E` L E H U G E L Despite meticulous techniques and the advanced experience, embolic stroke represents a major drawback of the carotid stenting procedure (CAS) The majority of the neurological complications are due to the intracerebral embolism of plaque fragments or thrombus during different procedural steps Anti-Embolization devices have been developed to reduce the incidence of embolic events during CAS (29–32) We have prospectively examined the outcome of CAS under cerebral protection using the distal occlusion balloon protection (GuardWire System, PercuSurge–Medtronic, Minneapolis, MN) to assess whether this therapy is comparable to historical controls of both carotid endarterectomy and CAS without Anti-Embolization Between February 1998 and February 2002, 238 patients (264 carotid stenoses) met the inclusion criteria and underwent CAS under protection using the GuardWire AntiEmbolization system Patients were eligible for treatment if they had more than or equal to 70% diameter stenosis of the internal carotid artery (ICA) evaluated by angiography according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria (2) We excluded the following patients from the treatment: multiple stenoses in the ICA, intracranial pathology, presence of angiographically visible thrombus, gastrointestinal bleeding in the last months, and hemorrhagic disorders All patients should receive aspirin 75 to 300 mg per day indefinitely and ticlopidine 250 to 500 mg per day or clopidogrel 75 mg per day for at least days and preferably week before the procedure and for month after it Unfractionated heparin (5000 IU intravenously) and atropine (1 mg intravenously) are routinely administered just after the introducer sheath is placed Patients were usually discharged the day after the procedure All patients underwent neurological examination, a duplex scan, and a computed tomography (CT) scan the day after CAS, a neurological examination and a duplex scan at 30 days and every months thereafter, and an angiogram at months Any change in the neurological status after CAS required repeated CT brain scan In our evaluation of the GuardWire system, we used the following endpoints: The primary clinical end points included any major/minor stroke, death, or myocardial infarction (MI) within the first 30 days postprocedure The periprocedural complications were defined as any major/minor stroke, death, or MI occurring in the early 48 hours The secondary clinical end points were the need of new intervention, angioplasty, or endarterectomy at months 15 Carotid Artery Stenting with the Distal Occlusion Anti-Embolization System 171 FIGURE 15-1 PercuSurge GuardWire system Angiographic endpoints were: angiographic success rate, defined as achieving a less than or equal to 30% residual stenosis, and angiographic restenosis, defined as a reduction of the arterial lumen diameter by more than or equal to 50% The procedural success was defined as a reduction in the stenosis to less than or equal to 30% and absence of any neurological complication, MI, or death A total of 264 carotid angioplasties were attempted in 238 consecutive patients (190 males, 48 females, mean age 71.2 ‫ ע‬9.4 years, range 40–91 years) Twenty-six patients had bilateral procedures Ninety-five stenoses were asymptomatic (36%), and 169 were symptomatic (64%) A total of 224 lesions were atherosclerotic, 30 were restenoses (postsurgical: 27, postangioplasty: 3), and were postradiation stenoses One lesion was an inflammatory arteritis and another one a posttraumatic aneurysm The mean percentage of stenosis was 82.3 ‫ ע‬9.2 % (70–99) Mean lesion length was 14.4 ‫ ע‬6.3 mm (5–50) and the mean arterial diameter was 5.0 ‫ ע‬1.3 mm (4–7.1); 118 lesions (45%) were calcified, and 188 were ulcerated (72%) DESCRIPTION OF THE GUARDWIRE SYSTEM The device consists of three main components (see Figs 15-1–15-3): The GuardWire temporary occlusion catheter: a 0.014-inch or 0.018-inch wire con- FIGURE 15-2 Export aspiration catheter mounted on a GuardWire temporary occlusion catheter 172 II Carotid Artery Stenting Techniques FIGURE 15-3 The GuardWire PercuSurge structed of a hollow nitinol hypotube incorporating into its distal segment an inflatable compliant balloon that is capable of occluding the ICA outflow The balloon diameter (3 to mm) is chosen depending on the artery diameter The GuardWire is available in lengths, 190 cm and 300 cm, and the wire accommodates monorail and over-thewire delivery systems for dilatation and stenting The terminal 3.5-cm segment of the wire can be shaped as needed to facilitate lesion-crossing maneuvers, much like coronary wires A Microseal that is incorporated at the proximal end of the wire, allowing inflation and deflation of the distal protection balloon (PB), utilizing a Microseal adapter The Microseal keeps the electrometric balloon inflated while allowing catheter exchange at the proximal end, similar to commonly used guide wires The aspiration catheter placed over the GuardWire to aspirate generated debris It may also be used to flush the ICA TECHNIQUES Figures 15-4 through 15-7 offer a visual summarization of the procedure techniques A 7F multipurpose guide catheter or a 6F long guiding sheath (depending on the stent type) is initially placed into the common carotid artery (CCA) via the femoral approach The GuardWire is then gently advanced through the guide catheter, the lesion is crossed, and the marker of the protection balloon placed or cm beyond it The Microseal adapter is then attached and the protection balloon slowly inflated with a fixed volume of dilute contrast, occluding the ICA and deriving vessel outflow towards the external carotid artery (ECA) It is important to verify by injection of contrast that the blood flow is totally interrupted in the ICA in order to ensure adequate antiembolization during the procedure If the ICAs are large in diameter, it is advisable to place the protection balloon high in the ICA at the base of the skull, where the ICA is smaller and the stability of the balloon is achieved Upon detaching the Microseal adapter, the occlusion balloon remains inflated Predilatation of the lesion or direct stenting are then performed under protection Any generated debris is removed from the ICA using aspiration alone or aspiration and flushing techniques Two protection techniques have been used: 15 Carotid Artery Stenting with the Distal Occlusion Anti-Embolization System 173 FIGURE 15-4 PercuSurge GuardWire system: procedure description (A) The lesion is crossed with GuardWire (B) The GuardWire balloon is inflated Technique 1: The occlusion balloon remains inflated during the whole procedure, and the aspiration is performed once after stent placement and postdilatation Technique 2: The occlusion balloon is deflated between predilatation and stent placement to restore the cerebral flow Aspiration is performed after each of these two stages The technique used depends on patient tolerance to the occlusion, the cerebral collateral circulation, the status of the contralateral artery, the duration of the procedure, and the technical problems encountered In both scenarios, the aspiration catheter is advanced over FIGURE 15-5 PercuSurge GuardWire system: procedure description (C) Intervention is performed under protection (right) GuardWire is used as a standard guide wire 174 II Carotid Artery Stenting Techniques FIGURE 15-6 PercuSurge GuardWire system: procedure description (D) Export catheter removes emboli and thrombus (right) the wire into the dilated area, with a 20-cc syringe connected to it to aspirate debris A minimum of two aspirations are performed successively Additionally, in our initial 40 cases, a flushing of the treated area was performed using saline injections through the guide catheter to drive the particles towards the ECA The injection was performed with an injection pump at a rate of mL per second for 10 seconds Two flushes may be performed: the first with the guiding catheter positioned at the carotid bifurcation, and the second with the catheter FIGURE 15-7 PercuSurge GuardWire system: procedure description (E) Flushing saline to external carotid artery (F) The GuardWire balloon is deflated 15 Carotid Artery Stenting with the Distal Occlusion Anti-Embolization System 175 near the protection balloon If only a single flush is possible, it is advisable to position the guiding catheter tip close to the occlusion balloon Finally, the Microseal adapter is reattached to the GuardWire, and the occlusion balloon is deflated, allowing normal flow to be restored If the angiographic result is satisfactory, the device is removed TECHNIQUES OF CEREBRAL PROTECTION ᭿ ᭿ ᭿ A total of 216 lesions were treated using the continuous occlusion technique Mean occlusion time (seconds): 375 ‫ ע‬182 (range 141–1480) A total of 46 lesions were treated by the second staged technique Mean dilation occlusion time (seconds): 320 ‫ ע‬150 (range 109–765), mean stent implantation occlusion time (seconds): 300 ‫ ע‬140 (range 120–720) Mean occlusion time for all lesions (in seconds) was 410 ‫ ע‬220 (120–1480) IMMEDIATE TECHNICAL SUCCESS Technical success (Figs 15-8, 15-9) was achieved in 262 out of 264 (99.2%) There were two failures to cross the lesion with the GuardWire system because of very tight calcified stenoses and excessive tortuosities of the CCA and ICA The procedures were successfully completed without cerebral protection In one patient, after completion of the procedure, deflation of the occlusion balloon using the Microseal adapter was impossible, owing to a kink in the Microseal junction This problem was managed by cutting the hypotube section of the GuardWire distally to the Microseal area, using scissors, and the balloon was then immediately deflated FIGURE 15-8 Tight left internal carotid artery stenosis Carotid angioplasty and stenting under protection with PercuSurge (implantation of Palmaz stent) 176 II Carotid Artery Stenting Techniques FIGURE 15-9 Tight left internal carotid artery stenosis Carotid angioplasty and stenting under protection with PercuSurge (implantation of Palmaz stent) Mild degrees of spasm have been seen at the location of the occlusion balloon in 10 patients, but without significant flow reduction We have never seen severe spasm or a dissection of the arterial wall All lesions were treated with endoprostheses except three postangioplasty restenoses We implanted 128 Palmaz stents (P204: 73, P154: 53, Corinthian: 2), 36 Wallstent stents, 101 nitinol self-expandable stents, and Jostent covered stent to treat the aneurysm The nitinol and Wallstent stents covered the bifurcation without jeopardizing the flow in the ECA All stents were well deployed TOLERANCE TO OCCLUSION BALLOON The occlusion during protection balloon inflation was well tolerated in 251 out of 262 cases (95.8%), out of which 62 had a significant contralateral ICA disease (stenosis or occlusion) Two types of intolerance were observed: Complete intolerance occurred in two patients (0.8%) immediately after inflation of the occlusion balloon: ᭿ ᭿ One patient with total occlusion of the contralateral ICA who developed loss of consciousness and seizures The patient totally recovered after rapid balloon deflation CAS was successfully completed without Anti-Embolization One with poor collateral circulation from the circle of Willis who developed rapid loss of consciousness, but the procedure could be completed under protection The patient immediately recovered after the occlusion balloon deflation 15 Carotid Artery Stenting with the Distal Occlusion Anti-Embolization System 177 Partial transient intolerance (occurred in nine patients: 3.4%) beginning approximately minutes after flow interruption with transient symptoms such as agitation, brief loss of consciousness, or transient neurological deficit The procedure was completed under protection All patients had rapid and complete recovery while the protection balloon was still inflated Seven of them had hypotensive response to dilatation with bradycardia, which could have promoted this intolerance Ten patients developed a spasm of the ICA above the dilated area at the location of the protection balloon, which rapidly responded to vasodilator therapy COLLECTED DEBRIS Aspiration of the debris was performed in all patients The aspirated blood samples were collected in filters (with a pore size of 40 ␮m) and analyzed using optic and electron microscopic techniques Visible debris was extracted from all patients [mean diameter: 250 ␮m (range 56–2652), mean number per procedure: 74 (range 7–145)] Different types of particles were found: atheromatous plaques, cholesterol crystals, calcified crystals, necrotic cores, fibrin, recent and old thrombi, platelets, macrophage foam cells, lipoid masses, and acellular material Figure 15-10 shows the images of the debris at electronic microscope and Figure 15-11 the distribution of particles for two patients Five neurological complications occurred (1.9%), including: (a) Four periprocedural complications (1.5%): ᭿ One amaurosis fugax in a symptomatic patient having a tight ulcerated right ICA stenosis after a Wallstent acute thrombosis during the procedure FIGURE 15-10 Debris retrieved with aspiration catheter Electronic microscope examination 178 II Carotid Artery Stenting Techniques FIGURE 15-11 Distribution of debris retrieved with aspiration catheter in two patients The thrombosis was seen on the angiogram after occlusion balloon deflation The balloon was quickly reinflated and abciximab injected (bolus of 0.25 mg per kg intravenously and 10 ␮g per mg continuous infusion for 12 hours thereafter) Thromboaspiration and flushing through the guide catheter were performed 10 minutes later and the protection balloon finally deflated The final angiogram showed no residual thrombus inside the stent Nevertheless, the patient developed amaurosis, which was probably the consequence of an embolism from the ECA through an ECA–ophthalmic artery communication Indeed, a communication between the ECA and the ophthalmic circulation was noted after careful angiographic inspection A total of three transient ischemic attacks (TIAs) occurred: ᭿ ᭿ One TIA with transient hemiparesis after a procedure of CAS for a tight asymptomatic left ICA stenosis in a patient who had a prolonged occlusion time (19 minutes) No evidence of ischemia was detected on subsequent serial CT examinations Two TIAs with brachial monoparesis, without sign of ischemia on CT scan examination (b) One intracerebral hemorrhage with hemiplegia on the third day after a CAS procedure under abciximab (same protocol as previously described) in a patient having a symptomatic subocclusion of the right ICA He partially recovered months later Cardiac events (0.4%) : ᭿ One symptomatic patient died from cardiac failure weeks after the CAS procedure No MI occurred during the hospital period or in the 30 days after CAS The overall 30-day incidence of neurological complications and death was 2.5% (amaurosis: 0.8%, TIA: 1.3%, and death: 0.4%) No episode of cranial nerve palsy occurred FOLLOW-UP At a mean follow-up of 23 ‫ ע‬12 months (range 1–46 months), four deaths occurred: one patient died from a major stroke located at the contralateral side of the previously treated 15 Carotid Artery Stenting with the Distal Occlusion Anti-Embolization System 179 FIGURE 15-12 Kaplan-Meier actuarial curve demonstrating event-free survival (myocardial infarction, any stroke, death) ICA at months, two other patients died from myocardial infarction, and one patient died from cancer No minor or major stroke occurred during the follow-up period One asymptomatic restenosis was observed at months and was treated successfully by balloon angioplasty The event-free survival was 97% at 36 months (Fig 15-12) CLINICAL AND TECHNICAL IMPLICATIONS The frequency of debris migration and distal embolism has been demonstrated by ex vivo human carotid stenting techniques (45) and confirmed by clinical studies (12,46–48) The number of embolic particles generated by percutaneous techniques seems to exceed that of endarterectomy (43,45,46) Although their clinical significance has not been documented yet (46,49), their presence could not have any beneficial effect on the brain Furthermore, the minimum particle size capable of producing ischemic events has not been determined Various patient and plaque characteristics have been suggested as predictors of debris generation and embolic events (36,45,50) to define high-risk groups for CAS procedures In our study, debris was extracted from all patients, even in lesions that theoretically are thought to be at low risk for cerebral embolism (restenosis, echogenic plaques, concentric lesions), suggesting that the risk of embolization is independent of the nature of the plaques Additionally, stent deployment does not provide sufficient protection against embolic plaque debris migration In all series of CAS, embolic risk exists regardless of the implantation techniques and the stent characteristics Manninen et al (50) compared endovascular stent placement with percutaneous transluminal angioplasty (PTA) of carotid arteries in cadavers in situ and found no difference with respect to distal embolization Vitek et al (51), in 1984, first reported a case of successful innominate artery angioplasty where the risk of cerebral embolization was reduced by temporary occlusion of the origin of the right CCA with a second balloon catheter In the last decade, as a testimony to suboptimal results and the need for embolic risk elimination, several Anti-Embolization strategies during CAS have been proposed (52,53) The GuardWire system was first tested in animals by Oesterle et al (54), followed by clinical use (55) in 27 coronary interventions on saphenous vein grafts It has been shown that the system was compatible with routine angioplasty procedures, capable of containing and retrieving atherosclerotic debris, and might aid in the prevention of distal embolization The device has been proposed for cerebral protection during CAS One of its advantages 24 Clinical Investigations and Protocols 321 Patient Name: NIH Stroke Scale Date of evaluation mm dd yy Scale Definitions Level of consciousness (LOC) 0ϭ Alert, keenly responsive: 1ϭ Drowsy; arousable by minor stimulation to obey, answer, or respond: 2ϭ Stuporous: requires repeated stimulation to attend, or is obtunded and requires strong or painful stimulation to make movements (not stereotype) 3ϭ Coma, responds only with reflex motor or autonomic effects or totally unresponsive, flaccid araflexic LOC questions 0ϭ Answers both questions correctly 1ϭ Answers one question correctly 2ϭ Answers neither question correctly 9ϭ Untestable LOC commands 0ϭ Performs both tasks correctly, 1ϭ Performs one task correctly 2ϭ Performs neither task correctly Best Gaze 0ϭ Normal; 1ϭ Partial gaze palsy 2ϭ Forced deviation, or total gazed paresis is not overcome by the oculocephatic maneuver Visual 0ϭ No visual loss: 1ϭ Partial hemianopia: 2ϭComplete hemianopia: 3ϭBilateral hemianopia (blind including cortical blindness): 9ϭ Untestable Facial Palsy 0ϭ Normal facial movement; 1ϭ Minor paresis (flattened nasolabial fold, asymmetry on smiling); 2ϭ Partial paresis (total or near total paralysis of lower face); 3ϭ Complete paresis (absence of facial movement in upper and lower face) L arm motor Scoring for Arms and Legs: 0ϭ No drift: 1ϭ Drift: 2ϭ Some effort against gravity: 3ϭ No effort against gravity, limb falls; 4ϭ No movement: 9ϭ Untestable R arm motor Amputation, joint fusion L leg motor Explanation (L) arm: (R) arm _ (L) leg (R) leg _ R leg motor Limb ataxia 0ϭ Absent; 1ϭ Present unilaterally in either arm or leg; 2ϭ Present unilaterally in arm and leg or bilaterally; 3ϭ Untestable Sensory 0ϭ Normal, no sensory loss; 1ϭ Partial loss; patient feels pinprick is less sharp or is dull on the affected side; or there is a loss of superficial pain with pinprick but patient is aware he/she being touched; 2ϭ Dense loss Patient is not aware of being touched Best language 0ϭ No aphasia; normal; 1ϭ Mild to moderate aphasia; 2ϭ Severe aphasia; 3ϭ Mute Dysarthria 0ϭ Normal articulation; 1ϭ Mild to moderate dysathria; 2ϭ Near unintelligible or worse; 9ϭ Untestable Extinction and inattention 0ϭ No neglect (no flexion after seconds); 1ϭ Partial neglect; 2ϭ Complete neglect R distal motor function L distal motor function 0ϭ Normal; 1ϭ At least some extension after seconds, but not fully extended Any movement in the fingers which is not a response to a command is not scored; 2ϭ No voluntary extension after seconds Movement of the fingers at another time is not scored Total Other neurological factors Evaluator's Name not affecting NIH Scores: Evaluator's Signature Date FIGURE 24-1 Sample National Institutes of Health Stroke Scale (NIHSS) (adapted from www.nih.gov) 322 III Future Directions only the initial answer be graded and that the examiner not “help” the patient with verbal or nonverbal cues 1c–LOC commands: The patient is asked to open and close the eyes and then to grip and release the nonparetic hand Substitute another one-step command if the hands cannot be used Credit is given if an unequivocal attempt is made but not completed because of weakness If the patient does not respond to command, the task should be demonstrated to them (pantomime) and the result scored (i.e., follows none, one, or two commands) Patients with trauma, amputation, or other physical impediments should be given suitable one-step commands Only the first attempt is scored 2–Best gaze: Only horizontal eye movements will be tested Voluntary or reflexive (oculocephalic) eye movements will be scored but caloric testing is not done If the patient has a conjugate deviation of the eyes that can be overcome by voluntary or reflexive activity, the score will be one If a patient has an isolated peripheral nerve paresis [cranial nerve (CN) III, IV, or VI], score a one Gaze is testable in all aphasic patients Patients with ocular trauma, bandages, preexisting blindness, or other disorder of visual acuity or fields should be tested with reflexive movements and a choice made by the investigator Establishing eye contact and then moving about the patient from side to side will occasionally clarify the presence of a partial gaze palsy 3–Visual: Visual fields (upper and lower quadrants) are tested by confrontation, using finger counting, or visual threat as appropriate Patient must be encouraged, but if patient looks at the side of the moving fingers appropriately, this can be scored as normal If there is unilateral blindness or enucleation, visual fields in the remaining eye are scored Score one only if a clearcut asymmetry, including quadrantanopia, is found If the patient is blind from any cause, score three Double simultaneous stimulation is performed at this point If there is extinction, the patient receives a one, and the results are used to answer question 11 4–Facial palsy: Ask or use pantomime to encourage the patient to show teeth or raise eyebrows and close eyes Score symmetry of grimace in response to noxious stimuli in the poorly responsive or noncomprehending patient If facial trauma/bandages, orotracheal tube, tape, or other physical barrier obscures the face, these should be removed to the extent possible and 6–Motor arm and leg: The limb is placed in the appropriate position: extend the arms (palms down) 90 degrees (if sitting) or 45 degrees (if supine) and the leg 30 degrees (always tested supine) Drift is scored if the arm falls before 10 seconds or the leg before seconds The aphasic patient is encouraged using urgency in the voice and pantomime but not noxious stimulation Each limb is tested in turn, beginning with the nonparetic arm Only in the case of amputation or joint fusion at the shoulder or hip may the score be "nine" and the examiner must clearly write the explanation for scoring as a "nine." 7–Limb ataxia: This item is aimed at finding evidence of a unilateral cerebellar lesion Test with eyes open In case of visual defect, insure testing is done in intact visual field The finger-nose-finger and heel-shin tests are performed on both sides, and ataxia is scored only if present out of proportion to weakness Ataxia is absent in the patient who cannot understand or is paralyzed Only in the case of amputation or joint fusion may the item be scored "nine," and the examiner must clearly write the explanation for not scoring In case of blindness, test by touching nose from extended arm position 8–Sensory: Sensation or grimace to pin prick when tested or withdrawal from noxious stimulus in the obtunded or aphasic patient Only sensory loss attributed to stroke is scored as abnormal and the examiner should test as many body areas [arms (not hands), legs, trunk, face] as needed to accurately check for hemisensory loss A score of two, "severe or total," should be given only when a severe or total loss of sensation can be clearly demonstrated Stuporous and aphasic patients will therefore probably score one or zero The patient with 24 Clinical Investigations and Protocols 323 brain stem stroke who has bilateral loss of sensation is scored two If the patient does not respond and is quadriplegic score two Patients in coma (item 1a ‫ ס‬three) are arbitrarily given a two on this item 9–Best language: A great deal of information about comprehension will be obtained during the preceding sections of the examination The patient is asked to describe what is happening in the attached picture, to name the items on the attached naming sheet, and to read from the attached list of sentences Comprehension is judged from responses here as well as to all of the commands in the preceding general neurological exam If visual loss interferes with the tests, ask the patient to identify objects placed in the hand, repeat, and produce speech The intubated patient should be asked to write The patient in a coma (question 1a ‫ ס‬three) will arbitrarily score three on this item The examiner must choose a score in the patient with stupor or limited cooperation, but a score of three should be used only if the patient is mute and follows no one-step commands 10–Dysarthria: If patient is thought to be normal, an adequate sample of speech must be obtained by asking the patient to read or repeat words from the attached list If the patient has severe aphasia, the clarity of articulation of spontaneous speech can be rated Only if the patient is intubated or has other physical barrier to producing speech may the item be scored "nine," and the examiner must clearly write an explanation for not scoring Do not tell the patient why he/she is being tested 11–Extinction and inattention (formerly Neglect): Sufficient information to identify neglect may be obtained during the prior testing If the patient has a severe visual loss preventing visual double simultaneous stimulation, and the cutaneous stimuli are normal, the score is normal If the patient has aphasia but does appear to attend to both sides, the score is normal The presence of visual spatial neglect or anosognosia may also be taken as evidence of abnormality Because the abnormality is scored only if present, the item is never untestable *Additional item, not a part of the NIH Stroke Scale score: A–Distal motor function: The patient’s hand is held up at the forearm by the examiner, and the patient is asked to extend his/her fingers as much as possible If the patient can’t or doesn’t extend the fingers, the examiner places the fingers in full extension and observes for any flexion movement for seconds The patient’s first attempts only are graded Repetition of the instructions or of the testing is prohibited MODIFIED RANKIN SCALE The Modified Rankin Scale is typically used as an outcome measure for recovering stroke patients (Fig 24-2) The scoring of this scale is based on levels of ability, ranging from “no symptoms” to “severe disability.” Often, if a patient is unable to provide accurate answers (i.e., overestimates ability to perform certain tasks and activities), it is recommended that a caregiver or family member be interviewed independently GLASGOW OUTCOME SCALE The GOS (Fig 24-2) is primarily used as an indicator of outcomes following a stroke or other brain injury and should therefore be taken into consideration as one component of a complete neurological exam that includes the other stroke scales (Fig 24-3) However, it 324 III Future Directions Modified Rankin Scale Date of evaluation mm dd yy Grade (0–6) Grade Description No symptoms at all No significant disability despite symptoms: able to carry out all usual duties and activities Slight disability; unable to carry out all previous activities but able to look after own affairs without assistance Moderate disability; requiring some help, but able to walk without assistance Moderate to severe disability; unable to walk without assistance, and unable to attend to own bodily needs without assistance Severe disability; bedridden, incontinent, and requiring constant nursing care Death Glasgow Outcome Scale Date of evaluation mm dd yy Grade (1–5) Grade Description Death Persistent vegetative state Severe disability (conscious, but disabled) Moderate disability (disabled but independent) Good recovery Evaluator's Name Evaluator's Signature Date FIGURE 24-2 Sample Modified Rankin Scale and Glasgow Outcome Scale (adapted from www.nih.gov) can be useful in ascertaining physical independence in patients without neurological deficits In patients that have not suffered any type or neurological insult, the GOS score is generally observed to be ULTRASOUND EXAMINATION A carotid duplex ultrasound study should be performed within 30 days prior to the procedure to ascertain carotid artery disease and to determine eligibility for CAS A carotid duplex 24 Clinical Investigations and Protocols 325 Modified Barthel Scale Date of evaluation mm dd yy Bowel control 0ϭ Incontinent (or needs to be given enema); 5ϭ Occasional accidents (Ͻ1/week) or needs help with enema or suppository; 10ϭ Continent; no accidents Able to use enema or suppository, if needed Bladder control 0ϭ Incontinent, or catheterized and unable to manage; 5ϭ Occasional accident (Ͻ1/day) or needs help with external device; 10ϭ Continent; no accidents Able to care for collecting device if used Grooming 0ϭ Needs help in grooming 5ϭ Independent; can wash face, comb hair, brush teeth, shave (can manage plug if electric razor) Toilet use 0ϭ Dependent; 5ϭ Needs help for balance, handling, or toilet paper; 10ϭ Independent; can get on and off, handle clothes, wipe, empty and clean bedpan Feeding 0ϭ Dependent; 5ϭ Needs help; e.g., for cutting food; 10ϭ Independent; able to put on assistive device Eats in reasonable time Bathing 0ϭ Dependent; 5ϭ Independent; able to use bath tub, shower, or take complete sponge bath without supervision Walking 0ϭ Dependent; 5ϭ Unable to walk, but independent with wheelchair for 50 yards; 10ϭ Can walk with help for 50 yards; 15ϭ Independent for 50 yards May use assistive devices, except for rolling walker Dressing 0ϭ Dependent; 5ϭ Needs help but does at least half of task within reasonable time; 10ϭ Independent; can tie shoes, fasten fasteners, undress Stairs 0ϭ Unable; 5ϭ Needs help or supervision; 10ϭ Independent up and down May use assistive devices Chair/bed transfers 0ϭ Dependent; 5ϭ Able to sit but needs maximum assistance to transfer; 10ϭ Minimum assistance or supervision; 15ϭ Independent Can lock a wheelchair, lift footrests, get out TOTAL Evaluator's Name Evaluator's Signature Date FIGURE 24-3 Sample Modified Barthel Scale (adapted from www.nih.gov) study should be performed in order to determine the vessel patency at postprocedure, month, months, 12 months, and yearly intervals The purpose of this exam is to identify significant stenosis and/or occlusions in the bilateral, common, internal, and external carotid arteries, as well as to identify abnormal flow directions in the vertebral arteries It is recommended that this ultrasound scan be performed by a vascular laboratory that is certified by the Intersocietal Commission for Accreditation of Vascular Laboratories (ICAVL) The ultrasonic scanner should be equipped with a to 7.7-MHz ultrasound transducer that is capable of two-dimensional B-mode imaging, pulse Doppler waveform analysis, and 326 III Future Directions measurement of the angle between the ultrasound beam and the vessel access In order to ensure optimal imaging, Doppler exam angles should use Doppler ultrasound beams at 60 degrees to the vessel access with angle cursor parallel to the vessel wall The patient is normally supine on the examination table, with the head slightly extended to provide better access to the neck A bilateral exam is recommended for all scans The exam can be completed in 30 minutes Abbreviations used in ultrasound label imaging: CCA, common carotid artery; ICA, internal carotid artery; ECA, external carotid artery; P, proximal; M, mid; D, distal; PSV, peak systolic velocity; EDV, end diastolic velocity Recorded images should include the CCA, ICA, and ECA with pictures that show the location of the disease and/or carotid stent ICA must be visualized CCA has characteristic diastolic reversal A “thump” may be heard at the stump The distal ICA velocity should be measured a minimum of cm distal to the stent (postprocedurally) Another means of determining severity of carotid artery stenosis (Table 24-5) is the commonly used ICA/CCA ratio ICA/CCA ratios greater than or equal to 4.0 indicate 70% or greater degree of stenosis Ratios less than 4.0 indicate stenosis less than 70% ICA Ratio ‫ ס‬Maximum PSV of DCCA, PICA, or MICA CCA Maximum PSV of DCCA or MCCA TABLE 24-5 CLASSIFICATION OF CAROTID ARTERY STENOSIS Percent Stenosis PSV EDV Normal Less than 50% 50% to 79% 80% to 99% Occluded (100%) 20–130 cm/sec 120–180 cm/sec 180–250 cm/sec Ͼ300 cm/sec No flow NA NA Ͻ 140 cm/sec Ͼ140 cm/sec No flow PSV, peak systolic velocity; EDV, end diastolic velocity; NA, not applicable INDEX Note: Page numbers in italics indicate figures; “t” following a page number indicates a table A Abciximab, 126–127, 279 as adjunct therapy, 184 AccuLink, 118 AccuLink carotid stent system, 196 AccuLink for Revascularization of Carotids in High-Risk Patients (ARCHER), 29 AccuLink for Revascularization of Carotids in High Risk Patients (ARCHER) study, 196–197 AccuNet, 293 AccuNet Distal Embolic Protection for Carotid Stenosis (ACCUNET) registry, 196 ACE inhibitors, in intracranial atherosclerosis, 275 Activated clotting time, GuardWire and, 182 Amaurosis fugax, following use of GuardWire system, 177, 178 American Heart Association, 29, 48, 49, 189, 294 Science Advisory Council, 24, 298 Amplatz wire, 99, 100 Anesthesia, for angioplasty and stenting in intracranial atherosclerotic stenoses, 279–280 for CAS, 127 Angiographic restenosis, 171 Angiography, brachiocephalic, 106 advantages and disadvantages of, 78t cerebral, following stent deployment, 132 for intracranial angioplasty and stenting, 283 intracranial, after stenting, 121 during CAS, 149, 150, 151 magnetic resonance, for patient evaluation, 125 success rate of, 171 to access lesion before predilation, 131 Angioguard filter, 43, 191–192, 196 Angioplasty(ies), and stenting, for intracranial atherosclerotic stenoses, 278–284 balloon, in recurrent carotid artery stenosis, 63 risks associated with, 277 carotid artery, alone, 295–296 and CAS, 20–21 microembolization during, 180t, 180–181, 181t, 182 complications of, 103 history of, 243 procedural success using, 171 or stenting, safety of, level-1 evidence of, 26–29 non-level-1 evidence of, 29 percutaneous transluminal, 20–21 stent-assisted, in intracranial stenosis, 277–278 Anti-embolization, rationale for, 106 risk of embolization during stenting and, 153–159 Anti-embolization catheter, Parodi, advantages and disadvantages of, 157 Anti-embolization device(s), 149, 294 assessment of, 164–166, 165, 165t cases with, 115 CBAS and, 157 clinical effectiveness of, 155–156 development of, 154 dissection of carotid artery and, 143, 144, 145 for distal embolic protection, 248–250, 251, 252 in emergency setting, case illustrating, 217, 218 intravascular filters, 111, 113, 113–114 mechanical, 164 occlusion balloon, 111–113, 111, 112, 113 “dead zone” of, 164–165, 166 proximal occlusion with flow reversal, 114, 114–115 removal of, 120–121 Anti-embolization protection, approaches to, 156t, 156–157 CAS with and without, 156, 156t illustrative cases and technical pearls, 211–220 Anti-embolization system(s), distal occlusion, CAS with, 170–188 nonocclusive, transcranial Doppler during use of, 168 Antiaggregate therapy, 279 Antibiotics, 279 327 328 Index Anticoagulants, in intracranial atherosclerosis, 275 Anticoagulation, monitoring of, during CAS, 148 Antiplatelet agents, hyperperfusion syndrome and, 145 in prevention of acute stent thrombosis, 147 Antiplatelet therapy, 106 Antispasmodic agents, 183 Antithrombosis, in intracranial atherosclerosis, 275 Aortic arch, anatomy of, 77–79, 78, 79, 80, 81, 90, 91 Arteries See Carotid artery(ies); Cerebral artery(ies) Aspiration catheter, monorail, 120 of GuardWire, 171, 172 Aspirin, 5, 106, 126–127, 275, 278–279, 284, 318, 319 distal occlusion anti-embolization system and, 170 pretreatment with, 184 Aspirin Versus Anticoagulants in Symptomatic Intracranial Stenosis (AVASIS) study, 275 Asymptomatic Carotid Atherosclerosis Study (ACAS), 39, 46, 157, 184, 293, 305 Asystole, transient, as complication of stenting, 137–138 Atherosclerosis, carotid, intracranial, cerebral arterial thrombosis due to, 262–264, 263 evaluation of cerebral blood flow in, 273–274 identification of symptomatic patient with, 273–274, 274 medical treatment of, 274–275 perfusion failure in, 258–262, 259, 260, 261, 273 posterior circulation, prognosis in, 272t prognosis in, 265 risk factors for, 255 stroke and, 255 pathophysiology of, 258–265 treatment success and restenosis in, 277t Atherosclerotic carotid bifurcation disease, obstructive, stroke and, 48 Atherosclerotic carotid plaque, stabilization of, 3–5 Atherosclerotic plaques, pathology and characteristics of, 256–258 white (stable), 256, 257 yellow, 257–258 Atherosclerotic stenoses, intracranial, angioplasty and stenting for, 255–290 anesthesia for, 279–280 follow-up in, 284 guide catheter for, 280–281 lesion navigation and angioplasty for, 281–283 patient preparation for, 278 patient selection for, 278 postprocedure management in, 283–284 premedication for, 278–279 technical considerations for, 278–284 Atropine, 131 distal occlusion anti-embolization system and, 170 elderly patients and, 138 pretreatment, stent postdilatation and, 137–138 sheath removal and, 137 B Balloon(s), angioplasty, 253 deflation of, 120 distal, protection using, during CAS, 164 distal occlusion, advantages and disadvantages of, 156–157 high-pressure, 119 low-profile coronary, 115 monorail, 115 occlusion, 111, 113, 113–114 “dead zone” of, 164–165, 166 postdilatation, 110, 119 protection, during CAS, 145–146 semicompliant, for intracranial angioplasty and stenting, 281 undersizing of, for intracranial angioplasty and stenting, 282, 283 Balloon angioplasty, in recurrent carotid artery stenosis, 63 risks associated with, 277 Balloon catheter, proximal See Parodi AntiEmboli System (PAES) Balloon dilation catheter, 131 Balloon-expandable Palmaz stent, 131 Balloon protection system, PercuSurge, 131, 132, 133 Balloon system, distal occlusion, 154 Bivalirudin, 319 Blood flow, cerebral evaluation of, in intracranial atherosclerosis, 273–274 in stenosis of cerebral arteries, 258 quantitative positron-emission tomography to assess, 261 Boston Scientific Wallstent, carotid version, 41 metallic self-expanding, 41 Boulton Expander, self-expanding nitinol stents, 41 Brachial artery, as approach to carotid artery, 101, 102 Brachiocephalic angiography, 106 advantages and disadvantages of, 78t Brachiocephalic vasculature, angiographic anatomy of, 77–89 Index in elderly patient, 79, 80 in young patient, 78, 77–79 Bradyarrhythmia(s), 106–107 transient, as complication of stenting, 137–138 Brain, prevention of emboli and, 155–156 C Cardiac failure, following use of GuardWire system, 178 Cardiologists, interventional, in multispecialty groups, 70, 72 Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS), 6, 24, 25, 26, 29–30, 36, 132, 153, 162, 189, 297 and survival free of ipsilateral stroke, 30, 30–31 Carotid angioplasty, alone, 295–296 and CAS, 20–21 microembolization during, 180t, 180–181, 181t, 182 complications of, 103 history of, 243 Carotid angioplasty/stenting trials, intermediate and longer-term outcomes from, 32t Carotid artery(ies), access to, 92–97 problems of, solving of, 99–100 techniques for, 90–102 vascular access and, 243–245, 244 anatomy of, 82, 82 brachial artery approach to, 101, 102 catheterization of, 92, 93, 97–98 cervical, direct approach to, 124–132 medications for, 126–127 patient evaluation for, 124–126, 126 tortuosity of, preventing stent delivery, 124, 125 common, guiding of sheath placement into, 92, 95–96, 98–99 lesions of, carotid access in, 100 tortuosities of, 90–92, 91 transcatheter occlusion of, Doppler flow patterns during, 202, 202 disease of, embolic background of, 21 endovascular treatment in, risk of distal embolization and, 211 obstructive, and evidence-based benefits of revascularization, 3–17 occlusive, approach to patient with, 5–7 endovascular therapy for, 18–22 radiation-induced obstructive, stenting in, 53, 54 dissection of, anti-embolization devices and, 143, 144, 145 as complication of CAS, 142–144 factors predisposing to, 142–143 prevention of, 143 treatment of, 144 329 distal internal, severe stenosis in, stenting in, 51 exposure of, access for, 127, 127, 128 external, 82, 82 compromise of, following stenting, 146, 146 microembolization via, 167 occluded, carotid access in, 100 internal, 82, 82, 84, 85 cervical, lesion site and, angiographic assessment of, 121 Doppler flow patterns during, with Parodi Anti-Emboli System, 202, 203 fibromuscular dysplasia of, 82–84, 84 stenting in, 53, 54–55 loop of, CAS and, 140, 141, 142, 143 occlusion of, 3, symptomatic, recommendations in, 14, 14t revascularization of, 13–14 stenting of, hemodynamic effects of, 35 subtotal occlusion of, string sign in, case illustrating, 217, 218 tortuous with severe angulations, filter placement in, cases illustrating, 212–216, 213, 214, 215 tortuosities of, 82–84, 83 “kinks” of, CAS and, 141–142 lesions of, characteristics of, and outcome of endovascular procedures, 157 middle, stenosis of, death and stroke rates due to, 270t prognosis in, 268–271 obstructive lesions of, components of, 160 ostial left common, severe stenosis in, stenting in, 51 perforation of, during CAS, 146–147 restenosis of, balloon angioplasty in, 63 spasm and pseudospasm of, following CAS, 139–142, 140, 141, 142, 143 Carotid artery stenosis, and transient ischemic attack, asymptomatic, CEA in, 295 carotid siphon, intracranial, prognosis in, 266–268 CEA for, complications of, 20 classification of, 326t intracranial, causes of clinical symptoms in, 273 death and stroke rates due to, 267t dynamics of, 255–256 endovascular, revascularization in, 276–277 stent-assisted angioplasty in, 277–278 surgical revascularization with craniotomy in, 275–276 symptomatic, surgical options in, 275–278 recurrent See Restenosis revascularization of, benefits of, in asymptomatic patients, 9–10 in symptomatic patients, 8–9 technical aspects of, 7, 7–8 330 Index Carotid artery stenosis (Continued) severe, in distal internal carotid artery, stenting in, 50 in ostial left common carotid artery, stenting in, 51 symptomatic, CEA in, 294–295 Carotid artery stent registry, global, 39–47 Carotid artery stenting (CAS), 6, 39 advantages of, 49 after CEA, 62, 63 and carotid angioplasty, microembolization during, 180t, 180–181, 181t, 182 and CEA, lesions amenable to, 126, 126 outcomes of, 48 anesthesia for, 127 as alternative to CEA, 23 CEA versus, 6, 6t clinical investigations in, and protocols for, 313–326 clinical protocol and periprocedural care for, 106–108, 107t complications of, 104 contraindications to, 55, 55t, 55–58, 56, 57t crossing of lesion in, 108–109 current indications for, 48–60 current recommendations for, 24–26, 25t current results of, 243 current status of, 298 embolic events during, risk factors for, 103, 104t embolization during, experimental and clinical evidence for, 153–155, 154 estimation of “rare” event rates in, 303–304, 304 evaluation of, randomized controlled trials of, 185 statistical and design issues in, 303–312 experimental design and interpretation of outcomes of, 305 failure of, crossing of lesion and, 245, 245 final angiographic assessment following, 121 follow-up assessments in, 319, 320t for high-risk surgical patients, 49–50, 50 for North American Symptomatic Endarterectomy Trial, 297 forecasting trends in, 70, 71t future directions in, 122 Glasgow Outcome Scale and, 323–324, 324 Health Insurance Portability and Accountability Act of 1996, regulations and, 316–317 historical review of, 67 in stroke prevention, 103 indications for, categories of, 49 informed consent for, 315–316 initial screening for, 313–315 interim analysis of, 310–311 lesions unsuitable for, 104, 105 loop of internal carotid artery and, 140, 141, 142, 142, 143 medications administered before, 126–127 microembolic profile during, 163, 163–164 microembolization during, 160–169 modifications of, for safety, 104–105 Modified Rankin Scale and, 323, 324 multispecialty groups in, 66–73 National Institutes of Health Stroke Scale and, 320–323, 321 neurological assessment during, 319–320 neurological complications of, 105, 105 optimal candidates for, 49t periprocedural medications for, 318–319 postdilatation in, 110, 119–120 postprocedure medications following, 319 postprocedure testing in, 319t predilatation of stenosis for, 115 rationale for, 116, 117 preprocedure medications for, 318, 318t preprocedure testing for, 317t, 317–318 procedural complications of, 137–152, 138t procedure for, 127–132, 128, 129, 130 randomized trials in, difference versus equivalency approach, 306–310, 307, 308 release of embolic particles during, 190 restenosis in-stent following See Restenosis, instent risk of embolization during, and antiembolization, 153–159 safe, considerations for, 103–106 secondary screening for, 315 selective, 296 spasm and pseudospasm of carotid artery following, 139–142, 140, 141, 142, 143 statistical testing of, alternative approaches for, 310 stent delivery devices for, and stents, 245–248, 246, 247, 248, 249, 250, 251 steps in, 108t success of, 21, 189 technique of, 108t, 108–109, 110 transcranial Doppler-detected microembolization during, 162–163 ultrasound examination for, 324–326 versus CEA, trials of, 297 with and without anti-embolization protection, 156, 156t with distal occlusion anti-embolization system, 170–188 Carotid artery stenting device(s), future of, and limitations of, 243–254 Carotid atherosclerosis, risk factor modification, 5t Carotid Atherosclerosis Study (ACAS) trial, 35 Carotid bifurcation angioplasty and stenting (CBAS), 157 anti-embolization devices and, 157 Index Carotid endarterectomy (CEA), 3, 4, 6, 48 anatomically high-risk group for, 50–51 and CAS, lesions amenable to, 126, 126 outcomes of, 48 CAS after, 62, 63 CAS as alternative to, 23 complications of, 11–13 coronary artery bypass graft and, 52 cost-effectiveness of, in asymptomatic patients, 10–11 discussion of, 45–46 for carotid stenosis, complications of, 20 high risk situations for, 104 history of, 18–20, 23, 39 in asymptomatic carotid stenosis, 295 in coronary artery disease, 52 in symptomatic carotid stenosis, 294–295 medically high-risk group for, 52 patients at high risk for, 185 randomized trials of, 23 rationale for, 294–295 recommendations for, 295 repeat, stroke and death rate following, 61 restenosis after, incidence of, 222t technically high-risk group for, 52–55, 53 timing of, 12–13 versus CAS, 6, 6t trials of, 297 Carotid Occlusion Stroke Study, 3, 14 Carotid registry center, active participants in, 40t and complications during carotid artery stenting, 44, 44, 45 anti-embolization protection, 43–44 stents placed by, complications of, 41–43, 42, 43 history of, 42 subsets studies, 43–45 clinical follow-up of, 44–45 survey of, discussion of, 45–46 limitations of, 41 methods and materials for, 39–41 results of, 41–45 symptomatic versus asymptomatic patient population and, 41–43 Carotid Revascularization Endarterectomy Versus Stent(ing) Trial (CREST), 6–7, 28, 157–158, 185, 197–198, 293, 298–300 aims of, 298–299 design of, 299 methods of, 299–300, 300 participation in, and credentialing for, 299 Carotid Revascularization with Endarterectomy and Stenting Systems (CARESS) Trial, 29, 131, 133 Carotid siphon stenosis, intracranial, prognosis in, 266–268 Carotid stenosis See Carotid artery stenosis Catheter(s) See also specific catheters aspiration, of GuardWire, 171, 172 331 for angioplasty and stenting in intracranial atherosclerotic stenosis, 280 guide, for angioplasty and stenting in intracranial atherosclerotic stenosis, 280–281 proximal balloon See Parodi Anti-Emboli System (PAES) retrieval, dedicated, 120 temporary occlusion, of GuardWire, 171–172 Vitek, 92, 93, 94, 95–96, 97, 97–98, 100 Cerebral artery(ies), anterior, 84, 86, 88 leptomeningeal anastomoses of, 88, 89 middle, occlusion of, study of, 258 stenosis of, 255–256 small penetrating artery occlusion at, 264–265 thrombosis at site of, 262–264, 263 transcranial Doppler sonography in, 256 xenon computed tomography in, 259, 260 stenosis of, cerebral blood flow in, 258 Circle of Willis, 87–89 filter anti-embolization systems and, 211 Clopidogrel, 5, 106, 126–127, 275, 278, 279, 284, 318, 319 acute stent thrombosis and, 147 distal occlusion anti-embolization system and, 170 pretreatment with, 184 Cochrane Collaboration, 27, 29 Cognitive function, measurement of, following CAS, 155 Communicating artery(ies), anterior, 87–88 posterior, 87–88 Computed tomography, single photon emission, 13 xenon, in middle cerebral artery stenosis, 259, 260 Contrast, following stent deployment, 132 Contrast encephalopathy, following CAS, 139 Cordis Johnson, self-expanding nitinol stents, 41 Coronary angioplasty, percutaneous transluminal (PTCA), recovery of emboli in, 155 Coronary artery bypass graft, and CEA, 52 Coronary artery disease, CEA in, 52 Coumadin, 319 Cox’s hazards ratio for stroke, 31 Cranial nerve, injuries of, as complication of CEA, 12, 13t Craniotomy, surgical revascularization with, in intracranial stenosis, 275–276 Cyclosporine, liver transplantation and, 157 D Dexamethasone, 279 Dextran 40, 279 Dipyridamole, 5, 278 Distal occlusion balloon system, 43 Doppler, transcranial, 8, 160–162, 161 332 Index Doppler (Continued) during use of nonocclusive antiembolization systems, 168 for detection of microemboli, 160, 161 transcranial sonography, in stenosis of middle cerebral artery, 256 E Embolization, distal, as complication of CAS, 149–152, 150, 151 asymptomatic, following CAS, 190 risk factors for, 149t during CAS, experimental and clinical evidence for, 153–155, 154 risk of, anti-embolization and, 153–159 Embolus(i), clinical significance of, 155–156 prevention of, brain and, 155–156 silent, incidence of, following CAS, 153–154, 154 Emergency setting, anti-embolization devices, case illustrating, 217, 218 Encephalodural arterio-synangiosis (EDAS), 275–276 Encephalopathy, contrast, following CAS, 139 Endarterectomy versus angioplasty in severe symptomatic carotid stenosis (EVA-3S), 28 Endotex, self-expanding nitinol stents, 41 Endovascular revascularization, in intracranial stenosis, 276–277 Endovascular therapy, in restenosis following CEA, 62–64 EPI filter protection system, 131, 132 Etomidate, 281 European Carotid Surgery Trial (ECST), 18–19, 26, 36, 46, 295 European Stroke Initiative Recommendations for Stroke Management-Update 2003, 26 Export catheter, 120 Extracranial-intracranial (EC-IC) Bypass Study, 268, 269, 271, 275 Extracranial-intracranial (EC-IC) bypass surgery, 13–14 F Fibrinolytics, 183, 283 Fibromuscular dysplasia, of internal carotid artery, 82–84, 84 stenting in, 53, 54–55 Filter(s), difficult retrieval of, case illustrating, 216–217, 217 distal, strengths and weaknesses of, 157 EPI protection system for, 131, 132 Filter Wire EX, 196 intravascular, 111, 113, 113–114 removal of, 120 Filter anti-embolization systems, 211 advantages of, 211 disadvantages of, 211 features of, 212, 212t intravascular, 189–200 components of, 191 features of, 192t ideal, characteristics of, 191 technical application of, 191 nonrandomized registries of, 196–197 randomized clinical trials of, 197–198 steps in use of, 212 Filter devices, in vitro and clinic evaluation of, 195–196 Filter Wire EX filters, 196 Filter Wire EZ, 193–194, 194 Fluoroscopic unit, C-arm of, for visualization of internal carotid artery, 129, 130, 131 Flushing, GuardWire and, 183–184, 184 Food and Drug Administration (FDA), 298 G Glasgow Outcome Scale, CAS and, 323–324, 324 Glidewire, 94, 95–96, 97–98, 99, 100, 129 Glycoprotein (GP) IIB/IIIA antagonists, hyperperfusion syndrome and, 145 Glycoprotein (GP) IIB/IIIA inhibitors, GuardWire and, 182 Gray scale median, GuardWire, 155, 164, 170, 171 advantages and disadvantages of, 156–157 aspiration catheter of, 171, 172 aspiration of debris with, 177, 177–178, 178 cerebral protection during use of, 182, 183 clinical and technical implications of, 179–180 components of, 171, 171–172, 172 flushing and, 183–184, 184 follow-up of use of, 178–179, 179 immediate technical success of, 175, 175–176, 176 limitations of, 180–183 microembolization related to, 180t, 180–181, 181t Microseal of, 172 procedural considerations and late outcome in use of, 184–185 procedure techniques for use of, 172–175, 173, 174 protection techniques used with, 172–173 techniques of cerebral protection and, 175 temporary occlusion catheter of, 171–172 tolerance of occlusion and, 183 tolerance to occlusion balloon with, 176–177 GuardWire-plus, 121 Guidant AccuLink, self-expanding nitinol stents, 41 Guidant AccuNet system, 195, 195 Guide catheter, for angioplasty and stenting in intracranial atherosclerotic stenosis, 280–281 Index Guide wire(s), for intracranial angioplasty and stenting, 280–281 spasm, induced by removal, 139, 140 Guiding catheters, for angioplasty and stenting in intracranial atherosclerotic stenosis, 280–281 H Health Insurance Portability and Accountability Act of 1996 regulations, CAS and, 316–317 Hematomas, as complication of CEA, 12 Hemorrhage, intracerebral, as complication of CEA, 11 intracranial, as complication of CAS, 148, 148–149 following use of GuardWire system, 178, 183 Hemostasis, access site, guiding of sheath removal and, 121 Heparin, 12 distal occlusion anti-embolization system and, 170 during CAS, 148 hyperperfusion syndrome and, 145 intravenous, 275, 279, 284 Hyperperfusion syndrome, following CAS, 145 risk factors for, 145 following CEA, 144 management of, 145 risk factors for, 144 symptoms of, 144 Hypertension, during CAS, nitroglycerin or Nipride during, 148 Hypotension, sustained, following CAS, 138–139 I Inflation device, for intracranial angioplasty and stenting, 282 Informed consent, for CAS, 315–316 Intracranial vasculature, angiograms of, after stenting, 121 during CAS, 149, 150, 151 Isolated hemisphere, 88, 88 Isosorbide dinitrate, 279 J Johnson SMART, self-expanding nitinol stents, 41 Jomed Sito, self-expanding nitinol stents, 41 L Leicester trial, 27 Lenox Hill TCD analysis, 164 technical points of, 165–166 Lexington trial, 27, 29, 33 333 Lipoprotein, high-density, low-density, 3, 4, Liver transplantation, cyclosporine and, 157 M Magnetic resonance angiography, for patient evaluation, 125 Magnetic resonance imaging, Medications, administered before CAS, 126–127, 318, 318 MedNova EmboShield System, 192–193, 193 Mednova filter, 43 MedNova NeuroShield, 196 Medtronic AVE Carotid Distal Protection Device (DPD), 194–195 Medtronics, self-expanding nitinol stents, 41 Microcatheter-guide wire, 280, 281 Microembolic profile, during CAS, 163, 163–164 Microembolization, during carotid angioplasty and stenting, 180t, 180–181, 181t, 182 during CAS, 160–169 transcranial Doppler-detected, during CAS, 162–163 via external carotid artery, 167 Microembolus(i), transcranial Doppler for detection of, 160, 161 Microseal adaptor, 120 Microvena filter, 43 Microvena TRAP system, 194 Montefiore Vascular Symposium, 298 Moya-moya Disease, 276 Multidisciplinary Consensus Committee, 298 Multispecialty groups, assessment of environment by, 68–70 creation of, 72–73 in CAS, 66–73 interventional radiologists in, 68, 71 interventional cardiologists in, 70, 72 mission statement of, 67 need for, 66–67 reasons for forming, 71–72 specialists in, 68, 69t strategic planning for, 67 vascular surgeons in, 68–70, 71 Myocardial infarction, as complication of CEA, 12 N National Clinical Guidelines for Stroke, 25 National Institutes of Health (NIH), 293 classification of neurologic complications, 40–41 Stroke Scale, 106 CAS and, 320–323, 321 Neurological status, changes in, complications causing, 149, 150 monitoring of, during CAS, 149 NeuroShield, 196 Nimodipine, 279 334 Index Nipride, intravenous, during CAS, 145 in hypertension during CAS, 148 Nitinol self-expanding stent, 118 Nitroglycerin, 107, 283 intravenous, in hypertension during CAS, 148 Nitroglycerin paste, 279 North American Percutaneous Transluminal Angioplasty Register, 295–296 North American Symptomatic Carotid Endarterectomy Trial (NASCET), 18, 19, 26, 34, 36, 39, 46, 49, 170, 184, 293, 294–295 complications of carotid surgery and, 19, 20t exclusion criteria from, 19, 19t intermediate and longer-term outcomes from surgical trials, 31, 31t O Occlusion, tolerance of, 183 Occlusion system, proximal, advantages and disadvantages of, 157 P Palmaz stents, balloon-expandable, 41, 131 Papaverine, 283 Parodi Anti-Emboli System (PAES), 201–210 as unique system, 207–208 background of, 201 clinical results with, 207 description of, 203–205, 204, 205, 206 flow reversal technique for, 205–206 flow reversal using, 202 particle collection by, 208 procedure caveats in use of, 206–207 Parodi Anti-Embolization catheter, advantages and disadvantages of, 157 Parodi Anti-Embolization system, 114, 114–115 Perclose X-Act, self-expanding nitinol stents, 41 PercuSurge balloon protection system, 131, 132, 133 PercuSurge-Medtronic GuardWire system See GuardWire Perfusion failure, in intracranial atherosclerosis, 258–262, 259, 260, 261, 273 Pittsburgh Vascular Institute, 34 Plasminogen activator, recombinant tissue-type, 281 Platelet-active drugs, in intracranial atherosclerosis, 275, 279 Plavix See Clopidogrel Positron-emission tomography, quantitative, of cerebral blood flow, 261 Postdilatation balloon, 110, 119 Precise 888, self-expanding nitinol stents, 41 Protamine, to reverse anticoagulation, 148 Protamine sulfate, 12 Proximal balloon catheter See Parodi AntiEmboli System (PAES) Proximal protection devices, 250–253 R Radiation-induced obstructive carotid artery disease, stenting in, 53, 54 Radiologists, interventional, in multispecialty groups, 68, 71 Rankin Scale, Modified, CAS and, 323, 324 Registry Study to Evaluate the NeuroShield Bare Wire Anti-Embolization System and XAct Stent in Patients at High Risk for Carotid Endarterectomy (SECURITY), 29, 197 ReoPro, 279 Restenosis, angiographic, 171 carotid, balloon angioplasty in, 63 definition of, 222 following CEA, 61–65 repeat surgery in, 61 treatment of, endovascular, 62–64 indications for, 62 in-stent, 36, 36, 116, 116, 221–242 diagnosis of, 224–225, 224–233, 226–227, 228–233 evaluation of, 35 incidence of, 222t long-term angiographic follow-up in, 233–238, 234–237, 238, 239 management of, 238–239, 239 natural history of, 223–224 pathophysiology of, 222–223 Retrieval catheter, dedicated, 120 Revascularization, benefit of, evidence-based, obstructive carotid artery disease and, 3–17 Roadrunner wire, 131 S Saline flushing maneuver, 165 Saphenous Vein Graft Angioplasty Free of Emboli Randomized (SAFER) trial, 155 Schneider Corporation trial, 297 Sheath, guiding removal of, and access site hemostasis, 121 placement of, common carotid artery guiding of, 92, 95–96, 98–99 shuttle, 121 suturing and withdrawal of, 132, 134 Sheffield Vascular Institute, 27, 29, 34 Shuttle sheath, 121 Single photon emission computed tomography, 13 Spider filter system, 195, 195 Statins, in intracranial atherosclerosis, 275 Stenosis(es) See Carotid artery stenoses atherosclerotic See Atherosclerotic stenosis recurrent See Restenosis Stent(s), and stent delivery devices, for CAS, 245–248, 246, 247, 248, 249, 250, 251 Index balloon-expandable, 116, 117, 119 balloon-expandable Palmaz, 131 coronary, 277–278 deployment of, 109, 118 ultrasound (real-time), to confirm, 132, 134 diameter of, 118 length of, 118 restenosis in See Restenosis, in-stent self-expanding, 116–118, 117, 296–297 thrombosis of, acute, after CAS, 147, 147 Stent-protected Percutaneous Angioplasty of the Carotid Versus Endarterectomy (SPACE), 28 Stenting, and angioplasty, for intracranial atherosclerotic stenosis, 278–284 carotid artery See Carotid artery stenting (CAS) or angioplasty, safety of, level-1 evidence of, 26–29 non-level-1 evidence of, 29 Stenting and angioplasty with protection in patients at high risk for endarterectomy (SAPPHIRE) study, 29, 33, 36, 157–158, 197 String sign, in subtotal occlusion of internal carotid artery, case illustrating, 217, 218 Stroke, 3, 293 and death rate, following repeat CEA, 61 Cox’s hazard ratio for, 31 epidemiology of, 293–294 following CAS, 190 following use of GuardWire system, 182 future, prevention of, efficacy at level-1 evidence of, 29–33 efficacy at non-level-1 evidence of, 33–36 in intracranial stenosis, prognosis after, 265 incidence of, 39, 255, 293 intracranial atherosclerosis and, 255 pathophysiology of, 258–265 minor, classification of, 40 mortality rates for, 293–294 obstructive atherosclerotic carotid bifurcation disease and, 48 pathophysiology of, 294 perioperative, as complication of CEA, 11–12 prevention of, 23–28 rate of, and death rates, due to carotid artery stenosis, 267t, 270t risk of, 3, 4, vascular workup in, 273 Subclavian steal syndrome, 87, 87 T Thrombolytic agents, 281–282 Thrombosis, following use of GuardWire system, 178 335 Ticlopidine, 5, 275, 278, 279, 284, 319 distal occlusion anti-embolization system and, 170 pretreatment with, 184 Transcatheter Cardiovascular Therapeutics (TCT) 2003, 190, 197 Transient ischemic attack, carotid artery stenosis and, classification of, 40 following CAS, 190 following use of GuardWire system, 178, 182 Trials and registries, ongoing, 28t Trigeminal artery, primitive, 84, 85 Truncus bicaroticus, 79, 80 U Ultrasound, pretreatment, for CAS, 324–326 real-time, to confirm deployment of stent, 132, 134 Urokinase, 281 V Vascular access site, for CAS, complications related to, 137 Vascular spasm, 107 Vascular surgeons, in multispecialty groups, 68–70, 71 Verapamil, 279, 283 Vertebral artery(ies), 85–87, 86 Vertebrobasilar territory, intracranial stenosis of, prognosis in, 271–273 Veterans Affairs Symptomatic Trial, 295 Vitek catheter, 92, 93, 94, 95–96, 97, 97–98, 100 W Wallstent, 118, 119, 131, 133 Wallstent trial, 27 Warfarin, 5, 275 in intracranial atherosclerosis, 275 Warfarin-Aspirin Recurrent Stroke Study (WARSS), 275 Warfarin-Aspirin Symptomatic Intracranial Disease Study (WASID), 271–273, 275 Working Party for Stroke (Royal College of Physicians), 25 X Xact stent, 118 Xenon computed tomography, in middle cerebral artery stenosis, 259, 260 ... microembolization during carotid stenting Circulation 20 01;104:1999? ?20 02 49 Tubler T, Schluter M, Haufe M, et al Protected carotid artery stenting: acute results and 30-day follow-up Eur Heart J 20 00 ;21 :143(abst)... carotid stenting and angioplasty alone Arch Neurol 20 01;58:1410–1413 18 Parodi JC, Schonolz C, Ferreira M, et al Parodi Antiembolism System in carotid stenting: the first 21 0 19 20 21 22 23 24 ... complications, and follow-up Stroke 1996 ;27 :22 71? ?22 73 Diethrich EB, Ndiaye M, Reid DB Stenting in the carotid artery: initial experience in 110 patients J Endovasc Surg 1996;3: 42? ?? 62 10 Yadav JS,