|Year : 2018 | Volume
| Issue : 2 | Page : 105-112
Angioplasty and drug-eluting stent for vertebral artery stenosis
Nabil A Metwally1, Khalid M Sobh2, Mahmoud M Hassan1, Ali F El Hadad1, Shoukry Abd Al Aziz1
1 Neurology Department, Alazher Universality, Cairo, Egypt
2 Neurology Department, Alazher Universality, Assiut city, Egypt
|Date of Submission||16-Apr-2018|
|Date of Acceptance||12-Sep-2018|
|Date of Web Publication||27-Feb-2019|
Mahmoud M Hassan
Assiut, Asmaa allah square
Source of Support: None, Conflict of Interest: None
Objective To study the efficacy, safety, and feasibility of angioplasty and drug-eluting stents (DESs) in the treatment of vertebral artery stenosis.
Patients and methods The study was carried out on 20 patients (17 patients with vertebral artery endovascular stenting and three patients with angioplasty alone). The success rate, perioperative complications, and long-term effectiveness were evaluated.
Results A total of 17 DESs were implanted and three patients with angioplasty alone. The success rate was 100%. The degree of stenosis decreased from 78.25±10.17 to 11.50±7.45% (P<0.01). Complications were absent during the perioperative period. Follow-up was performed for 6 months. Two patients developed transient ischemic attack and one of them developed stroke and no cerebral ischemic events were noted in the remaining patients, suggesting a favorable outcome.
Conclusion Angioplasty and DESs is a safe and effective strategy for the treatment of symptomatic vertebral artery stenosis.
Keywords: angioplasty, endovascular, stenting, vertebral artery
|How to cite this article:|
Metwally NA, Sobh KM, Hassan MM, El Hadad AF, Abd Al Aziz S. Angioplasty and drug-eluting stent for vertebral artery stenosis. Al-Azhar Assiut Med J 2018;16:105-12
|How to cite this URL:|
Metwally NA, Sobh KM, Hassan MM, El Hadad AF, Abd Al Aziz S. Angioplasty and drug-eluting stent for vertebral artery stenosis. Al-Azhar Assiut Med J [serial online] 2018 [cited 2020 Jul 6];16:105-12. Available from: http://www.azmj.eg.net/text.asp?2018/16/2/105/253084
| Introduction|| |
About 25% of ischemic strokes occur in the vertebrobasilar territory. Around one-fifth of posterior circulation strokes occur in the setting of extracranial vertebral artery stenosis (VAS). VAS may occur either extracranially or intracranially, but it is often localized at the origin of the vessel as it arises from the subclavian artery. Vertebral artery (VA) is the second most common location of stenosis after internal carotid artery stenosis at the carotid bifurcation ,,. The mortality associated with a vertebrobasilar circulation stroke may be as high as 30% ,. Atherosclerosis most commonly affects the origin and proximal portion of the vertebral artery and is frequently associated with similar disease in the internal carotid artery . The most common mechanism of stroke in patients with VAS is intra-arterial embolism, rather than hemodynamic failure . Hemodynamic stroke is less commonly caused by VAS, because both VAS feed into one basilar artery . Also, in contrast to the internal carotid artery, the VA gives off numerous branches at the neck region, thereby facilitating a considerable collateral blood supply, which often reconstitutes the distal artery after occlusion at the origin . The optimum management of occlusive vertebral artery disease remains elusive. Medical therapy with antiplatelet or anticoagulant agents constitutes the initial management for stroke prevention. Surgical procedures are associated with relatively high rates of mortality and complications. Endovascular procedures have been proposed and can now be performed with safety and efficacy. Balloon angioplasty alone is limited by severe elastic recoil with a high propensity for restenosis. The use of stents seems to improve immediate and long-term results. Drug-eluting stents (DES) have been proposed recently to reduce restenosis rate. As with carotid angioplasty and stenting, there is always a risk of brain embolization during the procedure. Recently, protection devices have been used to reduce this risk ,,.
| Anatomy of vertebral artery|| |
The paired vertebral arteries are the first and largest branches of the subclavian arteries ([Figure 1]). The VA originates from the subclavian artery. It runs poster superiorly behind the anterior scalene muscle, commonly reaching the foramen of the transverse process of the sixth cervical vertebra. This first segment of the VA has been called V1 ,,. Furthermore, the artery runs vertically through the foramina of the transverse processes from C6 to C2 (the V2 segment), surrounded by the venous plexus. The spinal nerves lie behind. Between the foramina of C2 and C1, the artery curves laterally and somewhat anteriorly. Exiting from C1 begins the V3 segment, which curves backwards, running in the sulcus of the posterior arch of C1; it then forms a second upward and forward curve and reaches the foramen magnum, where the artery penetrates the dura and forms its last segment (V4). It is conceivable that these curves protect the VA, allowing it to accommodate more easily movement in the atlanto-occipital region ,,.
|Figure 1 A 66-year-old hypertensive male patient, ischemic heart disease, hyperlipidemic, diabetic, and a heavy smoker presented with diplopia, ataxia, and dysarthria. He was found on MRI to have acute ischemic infarcts in the cerebellum and occipital lobes. CTA showed an ostial stenosis of the left VA. CTA, computed tomography angiography; VA, vertebral artery.|
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| Patients and methods|| |
The study was carried out on 20 patients with VBI admitted to the Neurology Department, at Cairo, Al-Hussein University Hospital, Egypt. They were enrolled during the period from February 2014 to April 2016 in the Neurointervention Unit at Al-Hussein Hospital, after obtaining informed consent. The study has approved by the ethical committee of Azher Asiut university.
- Patients with posterior circulation ischemic symptoms that are present despite optimal medical therapy and VAS greater than 50% demonstrated by digital subtraction angiography (DSA).
- Asymptomatic unilateral significant stenosis of a dominant VA or significant stenosis with contralateral occlusion.
- Asymptomatic significant VAS or tandem lesions with evidence of resting posterior fossa hypoperfusion or diminished cerebrovascular reserve (may be considered for treatment due to high risk for infarction).
- Significant stenosis in an asymptomatic patient who needs collateral support [e.g. concurrent (bilateral) carotid artery (CA) occlusion].
- Asymptomatic patients with high-grade (>70% stenosis) lesions or progressive severity of the stenosis.
- Major functional impairment [Modified Rankin Scale (MRS)≥3].
- Severe renal impairment, concomitant severe liver, heart, or lung diseases/failure.
- Total occlusion of the vertebral artery.
- Refusal of intervention.
All the patients underwent the following: full medical and neurological history including history of associated comorbidities and risk factors, neurological examination before stenting, laboratory investigations including complete blood count, prothrombin time, partial thromboplastin time, liver and renal function tests, random blood sugar, lipid profile, serum uric acid, C-reactive protein, and cardiac enzymes if needed, assessment of the degree of vertebral stenosis by using vertebral artery duplex ultrasound before the procedure, MR angiography or computed tomography angiography and DSA on the arch and supra-aortic vessels may be used to confirm the stenosis and anatomy of the vertebral vessels; the degree of stenosis was determined according to North American Symptomatic Carotid Endarterectomy Trial criteria. The luminal diameter at the point of greatest stenosis (D sten) (A) and at the normal part of the artery (D dist) (B) were measured, and the degree of stenosis was calculated as follows: S=[1−(D sten/D dist)]×100% ; follow-up has been done for all the patients by full neurological evaluation, immediately after stenting, 1 month and sixth month after stenting with assessment of any neurological disorders [headache, delirium, altered mental state, transient ischemic attacks (TIAs), or stroke]. The severity of the disease is determined by using NIHSS score and functional disability determined by MRS.
All patients received aspirin in doses from 75 to 325 mg daily for at least 3 days before the procedure and continued indefinitely . Clopidogrel has been administered at a dose of 75 mg/day 5–7 days before the procedure.
- The procedure has been done for all patients selected for VAS underwent with local anesthesia in the femoral puncture site or axillary area in the axillary approach or radial area in radial approach and general anesthesia for patients who could not follow commands. The procedure was done under general anesthesia in three (15%) cases in noncooperative patients.
- Puncture has been done using an 18-G puncture needle and a 0.035 J-tipped hydrophilic guide wire with puncture and wire insertion (Seldinger technique) .
- Heparin (100 U/kg) has been administered during the procedure to maintain an activated clotting time of more than or equal to 250 s.
- During the initial placement of the diagnostic catheter in the VA, using a standard hydrophilic guide wire and a 6 Fr guide catheter, such as a 70–90 cm length Raabe sheath (Cook, Bloomington, Indiana, USA). The used catheter was a 6 Fr diagnostic catheters (Vertebral or Simmon II catheter; Boston Scientific or Cordis, 33 office around world California,USA).
- Diagnostic angiography has been done for visualization of both carotid bifurcations, and vertebral arteries and intracranial basilar arteries.
- Several projections: ‘Roadmap’ has been taken to show from where of the vertebral artery has originated ;then the guide wire is then removed to be replaced by a 0.035 Amplatz wire.
- The target subclavian artery was catheterized by a 100 cm 6 Fr soft tip guide catheter [Envoy (Cordis, Warren, New Jersey], Miami, Florida, USA) which is telescoped within the sheath and engage the VA ostium. The 6 Fr guide catheter usually provides adequate stability.
- Under the direction of a guiding wire, the top of the guiding catheter has been inserted into the 1–2 cm proximal to the affected vessels. When the lesions are located at the beginning part of the vertebral artery, the top of the guiding catheter is inserted into the subclavian artery. When the lesions are located at the intracranial segment of the vertebral artery and basilar artery, the guiding catheter is inserted into the affected vertebral artery. Then, the balloon-expandable paclitaxel-eluting coronary stent was guided into the lesioned artery, and inflation of the balloon is done once the location is confirmed.
- In case of a tortuous subclavian artery, a 0.014-inch wire or a large caliber coronary guiding catheter may be left in place in the subclavian artery for support.
- Continuous irrigation of the guide with heparinized saline (100 U/kg heparin per 500 ml ringer) using a rotating hemostatic valve (Y-adapter) was done to identify thrombus or bubbles.
- The wire has been carefully advanced through the lesion.
- In cases of severe stenosis (>80%), balloon angioplasty has been utilized (for prediction to allow the later stent passage) which was done in five (29.4%) patients.
- In three patients treated by simple balloon angioplasty only, a 3–4 mm angioplasty balloon (with a diameter less than that of the distal disease-free vertebral artery) was then placed across the stenosis and inflated to 8 atm using a standard pressure inflation device. Inflation is maintained for about 15 s. The balloon is then deflated and the degree of residual stenosis was viewed angiographically. The dilatation is repeated several times as needed (done in three patients one at ostium and two at the V4 segment due to difficult stenting).
- In the 17 patients in whom a stent is deployed, a guiding catheter was exchanged into the subclavian artery. Through this guiding catheter, a balloon-expandable paclitaxel-eluting coronary stent was applied. In all of the cases, resolute zotarolimus-eluting stents (R-ZES; Medtronic, Santa Rosa, California, USA) are utilized. DES is carefully placed into the stenosed segment on a roadmapping; the stent is placed (still under roadmapping) across the stenosis with the proximal end positioned at the origin of the vertebral artery from the subclavian artery.
- Care was taken to place the proximal end of the stent as close as possible to the upper contour of the subclavian artery. The stent was deployed first by manual inflation of the balloon to achieve better controllability, which was followed by controlled inflation by using a manometer. Stents of the same type with different sizes were used in all patients in the present study. Following the deflation of the balloon, control angiography is performed and the degree of residual stenosis was determined.
- Final angiographic assessment of the lesion site, the origin of the vertebral artery, and intracranial filling of vertebrobasilar arteries have been done.
- Guide catheter sheath removal and access site homeostasis are done finally.
The patients were transferred to the stroke unit for observation for 2 days, aspirin 75–325 mg once daily for life, clopidogrel 75 mg once daily for a 3–6 month duration, duplex control is done after 1 month, then after 6 months to identify in-stent restenosis of the stent (≥50% in-stent restenosis), recording of any procedural complications (puncture-related bradycardia, hypotension, hyperperfusion, stroke, TIA, and MI), and imaging of the brain computed tomography or MRI in case of vascular complications (TIA or stroke) occur.
| Results|| |
The study included 20 patients (17 patients with vertebral artery endovascular stenting and three patients with angioplasty alone), mean±SD age 68.20±10.51 years, 13 (65%) of them are men and seven (35%) are women, 17 (85%) patients were symptomatic and three (15%) patients were asymptomatic ([Table 1]). The major risk factors are hypertension in 12 (60%) patients, hyperlipidemia in 12 (60%) patients, diabetes mellitus in 11 (55%) patients, 11 (55%) patients have coronary artery disease, nine (45%) are smokers, five (25%) patients have compensated heart failure, and four (20%) patients have atrial fibrillation (AF) at the time of intervention ([Table 2]). Seventeen (65%) patients were symptomatic presenting stroke, TIA (55%), vertigo (45%), dizziness (40%), gait disturbance (20%), diplopia (15%), and drop attack (10%). Seven (35%) patients presented previous posterior circulation stroke, contralateral vertebral artery disease (75%) (occluded in 30% and hypoplastic in 45%) and concurrent carotid artery stenosis (20%) ([Table 3]). The frequency of pre-procedural vascular complications (stroke) is more in patients more than 70 years than the younger patients with statistically significant and TIA is more in patients younger than 70 years with statistically insignificant ([Table 4]). The frequency of pre-procedural vascular stroke is higher in patients older than 70 years compared to the younger patients with a statistically significant difference ,however TIA is more in patients younger compared to older patients with a statistically insignificant difference ([Table 4] and [Table 5]).
|Table 4 Frequency of stroke and transient ischemic attack is in patients less than 70 and more than or equal to 70 years|
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|Table 5 Frequency of stroke and transient ischemic attack between men and women|
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Among the 20 patients, stenting of VA by DES is done in 17 (85%) patients and three (15%) patients with angioplasty alone. The procedure was done under general anesthesia in three (15%) cases and other cases under local anesthesia; stenting was done using the transfemoral approach in 18 (90%) cases, one (5%) case through radial approach and one (5%) case through brachial approach due to high tortuosity of vertebral artery and severe angulation of the VA origin. The therapeutic procedures were performed in all the patients, 17 patients utilizing resolute zotarolimus-eluting stents (Medtronic). As regards the lesions distribution in the vertebral artery, most of them (75%) were located in the artery ostium, 20% in the V4 segment, and 5% in the V3 segment ([Table 6]).
Procedural results and complications
One (5%) patient has a local hematoma in the groin and treated conservatively with no surgical interference. Two (10%) patients developed TIA immediately after stenting and symptoms resolve within 3 h. One month after stenting no new neurological deficits and MRS score of the stroke patient was 1 and computed tomography angiography vertebral shows no restenosis, 6 months after the procedure one (5%) patient died suddenly with unexplained cause, another one (5%) patient with angioplasty alone developed stroke with NIHSS score 5 and DSA shows restenosis (˃50%) and two patients developed TIA (one patient with angioplasty alone and another one patient with DES) ([Table 7]). Comparing the degree of stenosis preprocedure to the degree of stenosis immediately after the procedure and 6 months later the result was as follows: preprocedure the stenosis ranged from 60 to 90%, immediately after the procedure was 0–20% and 6 months after the procedure was 5–50 which is statistically highly significant ([Table 8]). The degrees of VAS measured before, immediately after the procedure, and at 6-month follow-up of individual patients are shown in the table. Before the procedure, 80% of patients had stenosis of more than 70%, immediately after the procedure, no patient had residual stenosis of 25% or more and at 6-month follow-up, the rate of VA restenosis to a degree of at least 50% luminal narrowing was 5.3% ([Table 9]). The degrees of VAS measured immediately after and at 6-month follow-up of individual patients after angioplasty and DES are shown. Immediately after the procedure, no patient had residual stenosis of 25% or more in both procedures. At 6-month follow-up, the rate of VA restenosis to a degree of at least 50% luminal narrowing was 33.3 versus 0% in a patient with angioplasty alone and DES, respectively ([Table 10]). The frequency of vascular complications 6 months after the procedure was as follows: stroke complication 5%, restenosis 5%, TIA complication 15% ([Table 11]), and the frequency of stroke, TIA, and restenosis after 6 months of procedure as regard angioplasty and DES are more with angioplasty than DES ([Table 11] and [Table 12]).
|Table 7 Vascular complications (death and in-stent restenosis percentage) immediately, 1 and 6 months after stenting|
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|Table 8 Angiographic findings of percent stenosis of vertebral artery before the procedure, immediately after, and 6 months after the procedure|
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|Table 9 Proportional distribution of degree of vertebral artery stenosis before the procedure, immediately after, and 6 months after the procedure|
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|Table 10 Angiographic findings of percent stenosis according to the type of procedure|
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|Table 12 Frequency of stroke, transient ischemic attack, and restenosis after 6 months with regard to angioplasty and drug-eluting stent|
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| Discussion|| |
In the present study, the mean age of the patients is 68.20, this is consistent with Hatano et al. , Qureshi et al. , Yu et al. , Vajda et al. , and Werner et al.  in their studies the mean age was 68.2, 68, 65.9, 68, and 67.2 years, respectively. However in the study of Cloud et al. , Gupta et al. , and Yan et al.  the mean age by years was 56, 61, and 72.1 years, respectively. In our study, the mean degree of stenosis before the procedure was 78.25 which is consistent with Cloud et al. , Hatano et al. , Henry et al. , and Werner et al. . In them the mean degree of stenosis was 82, 81, 82.8, 78.8, and 81.3, respectively. However, in the study of Lugmayr et al. , Yu et al. , and Vajda et al.  the mean degree of stenosis was 85.1, 67.3, and 62, respectively. In our study, the mean degree of stenosis immediately after the procedure or residual stenosis was 11.50 which is consistent with Cloud et al. , Lugmayr et al. , Hatano et al. , Henry et al. , and Vajda et al. , in them the mean degree of stenosis was 8, 20.2, 16, 13, and 15, respectively, and is inconsistent with Yu et al. , Werner et al. , and Yan et al.  in them the mean degree of stenosis was 5.2, 5.7, and 3.7, respectively. In our study the two (10%) patients developed TIA immediately after stenting and symptoms resolve within 3 h; this rate is more than that observed in the Cloud et al.  study which reported that one (7%) patient experienced posterior circulation TIAs lasting less than 5 min. Weber et al.  study reported that one (2%) patient experienced posterior circulation stroke. Hatano et al.  study found that transient neurological complications occurred in two (2%) patients (hemiparesis and visual acuity disturbance). No patients experienced permanent neurological complications. Henry et al.  study reported that one (1.1%) patient presented with a TIA. No myocardial infarction, stroke, or death was seen after the procedure. None of the patients experienced cranial nerve palsies, wound infection, bleeding requiring transfusion, significant bradycardia, hypotension, or loss of consciousness after treatment with balloon inflations and stent placement. Werner et al.  study reported that only one (7.1%) patient had a TIA within 24 h after the procedure. No stroke related to the site treated during the procedure was observed. Yan et al.  study reported no TIA or stroke during the procedure, and Kocak et al.  study reported that the risk of periprocedural neurological complications was 5.5%, and the risk of posterior system stroke was 0.7%. On the other hand, the studies of Qureshi et al.  and Vajda et al.  reported no TIA or stroke during the procedure. In our study, vascular access occurred in 100% of cases and no technical complication occurred and this is consistent with Cloud et al. , Hatano et al. , Henry et al. , Vajda et al. , Yu et al. , Werner et al. , and Yan et al.  and unlike the study of Chastain et al. , Albuquerque et al. , Gupta et al.  in which vessel dissection has occurred 2), 3, and 3%, respectively and in the study of Weber et al.  technical complication occurred in one (2%) patient in the form of distal embolization where vascular access occurred without embolic protection device (EPD) and this patient present by stroke of posterior circulation. In the current study, there are no recorded cases with in-stent restenosis in 6 months after stenting and the result is inconsistent with Lin et al.  and Yu et al. . In contrast to the study of Lugmayr et al. , Gupta et al. , and Vajda et al.  who follow up patients with vertebral artery stenting after 6 month to detect the rate of restenosis and found the rate of in-stent restenosis is 63, 7, and 12%, respectively. The current study used DES with 6 months follow-up, some studies used DES with more than 6 months follow-up as the Akins et al.  study which used DES with 17 months follow-up without the rate of significant restenosis. The Edgell et al.  study used DES with 15 months follow-up without rate of significant restenosis and Zhou et al.  study used DES with 12 months follow-up with 17% of restenosis rate. In the current study, one case is recorded with restenosis 6 months after angioplasty alone due to difficult of stenting and this is consistent with Higashida et al.  who reported that radiographic follow-up studies after 6 months demonstrated three cases of restenosis involving the proximal vertebral artery; two were treated by repeat angioplasty without complication, and the third is being followed clinically while the patient remains asymptomatic. Storey et al.  reported that all three patients who underwent vertebral posterior thalamic artery (PTA) developed symptomatic restenosis within 3 months. Stents were successfully placed in all three, resulting in immediate reversal of stenosis and resolution of symptoms and showed no restenosis 3 months and 1 year after stent insertion. The Cloud et al.  study reported that the follow-up by catheter angiography at 1 year showed restenosis of the PTA site in all patients, with a mean degree stenosis at 1 year of 71%, and Henry et al.  reported that during the period of follow-up, six (8%) patients had neurological symptoms due to a restenosis as confirmed by the duplex scan and angiography. These restenosis included one total occlusion of the VA treated medically and five tight restenosis (stenosis >70%), which were treated successfully by new angioplasty.
| Conclusion|| |
The DESs in symptomatic patients with VAS is feasible and promising in terms of safety potential and effectiveness for preventing recurrent ischemia and restenosis than bare stent and angioplasty alone. However, a long-term clinical and angiographic follow-up is required to evaluate the durability of stent permeability.
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Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12]