Percutaneous transluminal angioplasty (dilatation) of carotid, vertebral, and innominate artery stenoses

Endovascular Metal Devices for the Treatment of Cerebrovascular Diseases

Cerebrovascular disease involves various medical disorders that obstruct brain blood vessels or deteriorate cerebral circulation, resulting in ischemic or hemorrhagic stroke. Nowadays, platinum coils with or without biological modification have become routine embolization devices to reduce the risk of cerebral aneurysm bleeding. Additionally, many intracranial stents, flow diverters, and stent retrievers have been invented with uniquely designed structures. To accelerate the translation of these devices into clinical usage, an in-depth understanding of the mechanical and material performance of these metal-based devices is critical. However, considering the more distal location and tortuous anatomic characteristics of cerebral arteries, present devices still risk failing to arrive at target lesions. Consequently, more flexible endovascular devices and novel designs are under urgent demand to overcome the deficiencies of existing devices. Herein, the pros and cons of the current structural designs are discussed when these devices are applied to the treatment of diseases ranging broadly from hemorrhages to ischemic strokes, in order to encourage further development of such kind of devices and investigation of their use in the clinic. Moreover, novel biodegradable materials and drug elution techniques, and the design, safety, and efficacy of personalized devices for further clinical applications in cerebral vasculature are discussed.

History and Current Status of Endovascular Management for the Extracranial Carotid and Supra-Aortic Vessels

Few procedures in the history of medicine have been more controversial than carotid artery stenting (CAS) for the management of carotid artery occlusive disease. Introduced just as the randomized trials were establishing carotid endarterectomy as the gold standard for carotid interventions, CAS has finally reached the point in its development when dedicated stenting systems are being tested in randomized clinical trials. Assisted by the concomitant use of distal protection devices, CAS has shown equipoise with endarterectomy in terms of safety at 30 days. This review summarizes the completed and ongoing CAS trials and the applications of endovascular techniques in the supra-aortic vessels.

Identifying High-Risk Patients for Percutaneous Transluminal Angioplasty of Subclavian and Innominate Arteries

We have performed percutaneous transluminal angioplasty for 7 subclavian (4 stenoses, 3 occlusions) and 2 innominate (both stenoses) artery obstructions in 7 patients by percutaneous femoral approach in all, and ipsilateral percutaneous brachial puncture in 2, patients. Initial success was obtained in 4 of the 6 stenoses (2 subclavian and both innominate) but in none of the 3 occlusions. Three of the 4 subclavian stenoses were located proximal to the vertebral artery origin and antegrade vertebral flow without subclavian steal was present in 2 of these lesions. Three patients had complications during the procedure. Two of them developed symptoms and signs of cerebral embolization. Both had shown antegrade vertebral flow and no evidence of subclavian steal in the initial angiogram. The third patient developed angina pectoris. The follow-up period ranged from 4 to 18 months (mean 10.8 months) and no re-stenosis was detected. Angioplasty appears suitable for management of a selected group of patients with nonocclusive lesions in whom subclavian steal phenomenon is evident in the initial diagnostic angiogram. The patients with antegrade vertebral flow are at a high risk of cerebral embolization during angioplasty.

Techniques for Endovascular Recanalization of Supra-Aortic Trunks

The supra-aortic arteries are no stranger to endovascular interventions. Since the 1980s, interventionists have been evaluating and refining the use of transluminal techniques for recanalizing stenotic and occlusive lesions in these large-bore, high-flow vessels. The authors present their methodologies for evaluating, selecting, and treating supra-aortic lesions with balloon angioplasty and stenting. Helpful suggestions are offered for optimizing the outcome of these endovascular approaches to atherosclerotic occlusive disease in the supra-aortic trunks.

Complications Associated with Extracranial Carotid Artery Interventions

Efforts to ameliorate the tremendous personal and financial ramifications of stroke in this country have focused on the recently validated stroke reduction potential of carotid endarterectomy. During the years in which numerous randomized trials compiled their evidence in favor of surgical treatment, the evolution of minimally invasive therapeutic alternatives to surgery spread to encompass nearly every vascular bed in the body. Only the fragile cerebrovascular system remains as the final challenge for interventionists.

Any revascularization alternative to carotid endarterectomy should achieve the same initial and long-term outcomes as the surgical gold standard, with comparable morbidity and mortality. After years of cautious, circumspect application, carotid angioplasty is now a contender for this role. Assisted by the newer stent technology, minimally invasive carotid interventions are entering clinical trials. While it is premature to discuss the stroke reduction potential of these catheter-based techniques, it is imperative that we recognize and prepare to treat the myriad, sometimes catastrophic, complications of these therapeutic approaches to carotid obliterative disease.

Results of Balloon Angioplasty in the Carotid Arteries

Purpose:

To report the experiences to date with percutaneous transluminal angioplasty (PTA) of the carotid artery and other supra-aortic vessels. A new coaxial dilatation system for carotid angioplasty with temporary balloon occlusion to avoid cerebral embolization is presented.

Methods:

PTA was performed in 220 patients with 245 stenosed or occluded supra-aortic arteries; among these were 74 carotid stenoses in the proximal common (n = 5), distal common (n = 1), internal (n = 65), and external (n = 3) carotid arteries. Duplex and B-mode ultrasonography, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, indium 111-labeled platelet scintigraphy, and/or angiography were used before and after PTA. Intravascular ultrasound imaging was also recently added for monitoring angioplasty results.

Results:

All patients but one with carotid lesions had symptoms of cerebrovascular insufficiency. Angioplasty was successful in 69 of the 74 carotid stenoses: proximal common (n = 5), distal common (n = 1), internal (n = 60), and external (n = 3). There were only 1 major (hemiparesis) and 2 minor complications. During the average 70-month observation period, restenosis has not occurred in any treated carotid artery. In a literature review of > 500 patients undergoing carotid angioplasty, the complication rate appears very low (mortality 0%; morbidity 2.1%) and comparable to that for carotid endarterectomy.

Conclusions:

Results of this review suggest that percutaneous transluminal angioplasty of the carotid artery is an effective alternative method to vascular surgery, particularly for patients with comorbidities that elevate the risks of surgery.

New possibilities in the endovascular treatment of supraaortic vessels

Cerebrovascular disease, including stroke, represents the third-leading cause of death in Hungary and a leading cause of disability among the elderly population. The majority of all strokes are ischemic, mostly secondary to thromboembolic disease of the supraaortic vessels. We investigated new therapeutic methods in the endovascular treatment of these diseases. Surgical revascularization of supraaortic trunk stenosis is associated with high morbidity and mortality rates. Balloon angioplasty has become an increasingly accepted treatment of stenoocclusive supraaortic arterial disease. Natural history data and treatment guidelines do not exist for innominate and proximal common carotid artery lesions. We have confirmed in a large series of innominate artery angioplasties that it is a safe and effective procedure with an excellent initial success rate, with a lower complication rate than the surgical option and with a similar long-term patency rate as for surgery.

In the largest published study on transfemoral angioplasty of ostial and proximal common carotid artery stenosis we have proved that endovascular treatment has high success rate with low stroke/death rate. Carotid stenting (CAS) is an evolving alternative to surgery in the treatment of patients with carotid stenosis. Stent selection is influenced by several factors, including the carotid anatomy and lesion characteristics. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which was designed for carotid bifurcation treatment. Data obtained from angiographic and computed tomographic images indicate that the stent provides adequate expansion and adaptation to the carotid bifurcation.

There are two types of restenosis after carotid artery interventions: the early restenosis develops mainly within the first 24 months after the revascularization procedure and its pathological background is myointimal hyperplasia; on the other hand late restenosis is rather due to progression of primary atherosclerosis and occurs more than 2 years after carotid endarterectomy (CEA). We compared the early restenosis rate in a consecutive series of CAS versus CEA patients at a single cardiovascular institution. The data suggest that the incidence of restenosis after stenting was less common than after surgery.

Our results may help vascular surgeons and interventional radiologists to consider risk versus benefit when deciding treatment options for supraaortic arterial stenosis.

Clinical and angiographic long-term outcomes of vertebral artery–subclavian artery transposition to treat symptomatic stenosis of vertebral artery origin

Object

Although angioplasty and stent placement for vertebral artery (VA)–origin stenosis have been performed using endovascular techniques, a high likelihood of restenosis has been observed in the long term. Therefore, the authors assessed the long-term clinical and angiographic outcomes in patients after VA–subclavian artery (SA) transposition.

Methods

Thirty-six patients (31 men, 5 women; mean age 64.3 years, range 46–76 years) underwent clinical evaluation (modified Rankin Scale [mRS]) and cervical angiographic evaluation preoperatively and within 1 month of and 6 months after VA-SA transposition undertaken to treat symptomatic stenosis of VA origin.

Results

Postoperative neurological deficits due to intraoperative brain ischemia did not occur, and MR imaging demonstrated no new postoperative ischemic lesions in any of the patients. One patient died of acute myocardial infarction 2 months after surgery and another developed a left thalamic hemorrhage (mRS score of 5) at 42 months postsurgery. None of the remaining 34 patients experienced further ischemic events, and the mRS score in all of these patients remained unchanged during a mean follow-up period of 54 months. The degree of VA-origin stenosis (preoperative mean 84%) was reduced to ≤ 30% after surgery (mean 2%). Long-term follow-up angiography in 29 patients (81%) revealed the absence of restenosis, defined as > 50% luminal narrowing, in all of them.

Conclusions

The clinical and angiographic long-term outcomes demonstrated here suggest that VA-SA transposition will be useful in patients with symptomatic stenosis of VA origin.

Safety and feasibility of drug-eluting stent implantation at vertebral artery origin: the first case series in Asians

BACKGROUND/PURPOSE

Studies of the safety and efficacy of drug-eluting stent (DES) implantation to treat vertebral artery (VA) ostial stenosis are lacking in the Asian population. The aim of this study was to evaluate the feasibility and safety of DES implantation to treat VA ostial stenosis in Asians.

METHODS

We retrospectively analyzed the medical and radiologic records of patients receiving VA origin stenting with DES from October 2004 to September 2006 in the National Taiwan University Hospital.

RESULTS

Eleven symptomatic patients (9 male; mean age, 72 years) with 11 lesions treated with DES were included. There were eight lesions treated with paclitaxel-eluting stents and three lesions treated with sirolimus-eluting stents. The success rate for implantation of a DES was 100%. The percentage of stenosis was significantly reduced after stenting (86+/-5 to 2+/-4%; p<0.001). No peri-interventional neurologic, vascular, or other medical complications were noted. All patients were asymptomatic at the mean follow-up time of 18.7+/-8.6 months (range, 6-30 months). Two patients received repeat angiography at 4 or 8 months after stenting. No significant in-stent restenosis was found.

CONCLUSION

Symptomatic VA origin stenosis can be treated safely and effectively with DES in Asians.

Percutaneous intervention for posterior fossa ischemia. A single center experience and review of the literature

OBJECTIVES

The purpose of our study was to evaluate the results of endovascular treatment of symptomatic vertebro-basilar insufficiency (VBI) unresponsive to medical therapy.

METHODS

Cardiac patients regularly followed in our cardiology clinic with symptoms suggestive of posterior fossa ischemia diagnosed by the attending cardiologist, had diagnostic or suspicious findings of vertebral artery stenosis on ultrasound evaluation, with reversed vertebral flow on Doppler examination. These patients were referred for selective vertebral and subclavian artery angiography. All patients (17 men, 11 women; mean age of 64 years, range 54-87) had critical lesions (> 70% stenosis) in the vertebral or pre-vertebral subclavian arteries or both. After confirmation of the severity of the lesions and feasibility for revascularization, all these patients underwent percutaneous intervention and stent placement. All patients were followed-up through clinic visits for a mean of 14.2 months, (range 3.5-24.3).

RESULTS

In our 28 patients that were treated, 25 vertebral and 10 subclavian stents were placed. Success (< 20% residual diameter stenosis, without stroke or death) was achieved in 27 patients (96%). One patient undergoing intervention for an ostial subtotal occlusion of the left subclavian artery, developed a minor posterior fossa transient ischemic attack. At follow-up, 25 patients (89%) were alive and 22 (88%) of those had no further neurologic complaints. Three (11%) patients that had vertebral artery stents, died during follow-up from cardiac complications, unrelated to the neurovascular intervention. One patient (3.5%) had recurrent symptoms with in-stent restenosis at 6 months with successful balloon angioplasty and resolution of symptoms. The two other patients with persistent symptoms (only dizziness) had no evidence of restenosis and underwent further work-up that has not clarified the etiology.

CONCLUSIONS

Posterior fossa ischemia is an under-diagnosed condition that occurs with relative frequency in cardiac patients. Awareness of this condition and adequate non-invasive testing permits identification of these patients. Endovascular treatment using coronary wires and stents including drug eluting stents, seems to be the treatment of choice for vertebral artery revascularization due to the high technical success rate, low complication rate, and long-term durability.

Percutaneous vertebral artery intervention: a necessary tool in every interventional cardiologist armamentarium

OBJECTIVES

The purpose of this study was to evaluate the results of endovascular treatment of symptomatic vertebrobasilar insufficiency unresponsive to medical therapy.

METHODS

Twenty-eight patients who were regularly followed up in our cardiology clinic with symptoms suggestive of posterior fossa ischemia and with diagnostic or suspicious findings on ultrasound evaluation were evaluated with selective vertebral and subclavian artery angiography. All patients (17 men, 11 women; mean age, 64 years; range, 54-87) had critical lesions (>70% stenosis) in the vertebral or subclavian arteries or both. Those lesions that were considered severe enough to explain the reported symptomatology underwent percutaneous intervention and stent placement. All patients were followed up through clinic visits for a mean of 14.2 months (range, 3.5-24.3).

RESULTS

In the 28 patients treated, 25 vertebral and 10 subclavian stents were placed. Success (<20% residual diameter stenosis, without stroke or death) was achieved in 27 patients (96%). One patient who had been undergoing intervention for a subtotal occlusion of the left subclavian artery developed a posterior fossa transient ischemic attack. At follow-up, 25 patients (89%) were alive, and 22 (88%) of those had no further neurological complaints. Three (11%) patients died during follow-up from cardiac complications. One (3.5%) patient had recurrent symptoms with in-stent restenosis at 6 months with successful balloon angioplasty and resolution of symptoms.

CONCLUSIONS

Posterior fossa ischemia is an underdiagnosed condition that occurs with relative frequency in the usual patient population that interventional cardiologists attend to. Endovascular treatment using coronary wires and stents including drug-eluting stents is the treatment of choice for vertebral artery revascularization due to its high technical success rate, low complication rate, and long-term durability.

Distal Embolization After Stenting of the Vertebral Artery: Diffusion-Weighted Magnetic Resonance Imaging Findings

PURPOSE

We retrospectively evaluated our experience with stenting of the vertebral artery in an effort to determine the risk of distal embolization associated with the procedure.

METHODS

Between June 2000 and May 2005, 35 patients with 38 stenting procedures for atherosclerotic disease of the vertebral origin in our institution were identified. The average age of the patients was 60.3 years (range 32-76 years). Sixteen of these patients (with 18 stents) had MR imaging of the brain with diffusion-weighted imaging and an apparent diffusion coefficient map within 2 days before and after procedure.

RESULTS

On seven of the 16 postprocedural diffusion-weighted MR images, a total of 57 new hyperintensities were visible. All these lesions were focal in nature. One patient demonstrated a new diffusion-weighted imaging abnormality in the anterior circulation without MR evidence of posterior circulation ischemia. Six of 16 patients had a total of 25 new lesions in the vertebrobasilar circulation in postprocedural diffusion-weighted MR images. One patient in this group was excluded from the final analysis because the procedure was complicated by basilar rupture during tandem stent deployment in the basilar artery. Hence, new diffusion-weighted imaging abnormalities were noted in the vertebrobasilar territory in 5 of 15 patients after 17 stenting procedures, giving a 29% rate of diffusion-weighted imaging abnormalities per procedure. No patient with bilateral stenting had new diffusion-weighted imaging abnormalities.

CONCLUSION

Stenting of stenoses of the vertebral artery origin may be associated with a significant risk of asymptomatic distal embolization. Angiography, placement of the guiding catheter, inflation of the stent balloon, and crossing the lesion with guidewires or balloon catheters may potentially cause distal embolization. Further studies to evaluate measures to increase the safety of vertebral artery stenting, such as the use of distal protection devices or short-term postprocedural anticoagulation, should be considered for patients with clear indications for this procedure.

Treatment of innominate arterial stenosis with self-expanding stent: long-term follow-up

We report our experience with the use of a self-expanding stent in the treatment of a severe innominate artery stenosis resulting in right upper limb ischemia. A 45-year-old woman was admitted for right upper limb ischemia, asymmetry of the carotid pulse and the lack of pulse in the right upper extremity. The patient had a history of chain smoking, hypertension, hypercholesterolemia, and acute myocardial infarction one year ago. She was diagnosed of the innominate artery stenosis by angiography one year ago at another hospital. At the time of admission her blood pressure was normal in the left arm and absent in the right upper limb. Arteriography showed a severe stenosis subocclusion of the innominate artery with an inverse flow of the ipsilateral vertebral artery. As the patient was not considered to be a surgical candidate due to instable angina, stent placement was indicated. After placement through an axillary approach an angiogram showed a patent right subclavian artery without residual stenosis. Angiographic follow-up showed a patent innominate arterial lumen two years after the procedure. The patient continued to be asymptomatic during six years follow-up. Blood pressure remained normal in both upper extremities, without any ischemic signs. Our experience indicates that placement of an endovascular stent is an effective therapeutic option in selected patients with symptomatic stenosis in the innominate artery when a surgical treatment is contraindicated.

The impact of lesion length on angiographic restenosis after vertebral artery origin stenting

OBJECTIVE

To evaluate the effect of lesion length on in-stent restenosis (ISR) of vertebral artery (VA) origin stenting.

METHODS

We retrospectively analyzed the medical and radiological records of patients receiving VA origin stenting from March 1999 to June 2005. They were subdivided according to lesion length. ISR was defined as >50% diameter narrowing in stent.

RESULTS

Eighty symptomatic patients (64 male, mean age 72 years) with 90 lesions treated with balloon expandable tubular coronary stents were enrolled. There were 34 patients with 38 short lesions (length<or=5 mm, group 1), 37 patients with 42 medium lesions (length>5 mm, <10 mm, group 2) and 9 patients with 10 long lesions (length>or=10 mm, group 3). Eighty seven bare-metal stents and 3 drug-eluting stents were implanted. Repeat angiography was done in 40 lesions (44%) at 11.7+/-9.6 months. The ISR rate in group 1, 2, 3 is 21%, 29%, and 50% (p=0.486). Multivariable Cox regression analysis showed lesion length was the only significant independent predictor of ISR (hazard ratio: 1.19, p=0.039).

CONCLUSION

ISR of VA origin stenting is common. Lesion length is an important predictor of ISR in VA origin stenting.

Fatal Intraventricular Hemorrhage After the Extracranial Carotid Artery Angioplasty and Stent Placement

We report on a 72-year-old female with an unusual intracranial bleeding complication after an extracranial carotid artery stenting procedure performed for a tight left ICA stenosis associated with contralateral carotid occlusion. Two hours after the procedure, the initial signs of intracranial bleeding appeared that led to the patient's demise 5 days later. A brain CT showed and autopsy proved massive intraventricular bleeding. To our knowledge, our case is only the second report of isolated reperfusion intraventricular hemorrhage post-CAS.

Symptomatic ostial vertebral artery stenosis treated with tubular coronary stents: clinical results and restenosis analysis

PURPOSE

To evaluate the feasibility and safety of stent implantation to treat ostial vertebral artery stenosis.

METHOD

Fifty-eight symptomatic patients (44 men; mean age 72 years, range 54 to 88) with 67 ostial vertebral artery lesions received 67 balloon-expandable coronary stents. Follow-up angiography was performed if restenosis was suspected or during later catheterization for other indications. Restenosis was defined as >50% diameter narrowing.

RESULT

Technical success was 100%. Periprocedural neurological complications included 2 (3.4%) posterior and 1 (1.7%) anterior strokes. Other complications included 1 (1.7%) massive gastrointestinal hemorrhage requiring blood transfusion and endoscopic therapy, 1 (1.7%) femoral pseudoaneurysm requiring surgical repair, and 1 (1.7%) large shoulder hematoma secondary to a ruptured small branch of the thoracoacromial artery. Antiplatelet medication was discontinued in the ulcer patient, and the vertebral stent occluded at 8 months. At a mean follow-up of 31.3+/-17.1 months, 1 (1.7%) patient died after coronary bypass 2 months after stenting. One (1.7%) patient reported recurrent dizziness at 14 months and had angiographic evidence of in-stent restenosis. Angiographic evaluation of 32 (48%) lesions at a mean 11.0+/-9.6 months uncovered restenosis in 8 (25%) vessels, including the 2 cases noted above. Aside from these 2 patients, none of the other patients with restenosis were symptomatic. Multivariant Cox regression analysis showed reference vessel diameter as the only independent predictor of restenosis.

CONCLUSION

Symptomatic ostial vertebral artery stenosis can be treated with relative safety using coronary techniques and equipment. Reference vessel diameter was the only predictor of restenosis in vertebral artery ostial stents.

History and current status of endovascular management for the extracranial carotid and supra-aortic vessels

Few procedures in the history of medicine have been more controversial than carotid artery stenting (CAS) for the management of carotid artery occlusive disease. Introduced just as the randomized trials were establishing carotid endarterectomy as the gold standard for carotid interventions, CAS has finally reached the point in its development when dedicated stenting systems are being tested in randomized clinical trials. Assisted by the concomitant use of distal protection devices, CAS has shown equipoise with endarterectomy in terms of safety at 30 days. This review summarizes the completed and ongoing CAS trials and the applications of endovascular techniques in the supra-aortic vessels.

Percutaneous Transluminal Angioplasty and Stent Placement for Subclavian Steal Syndrome With Concomitant Anterograde Flow in the Left Internal Mammary Artery Graft for Coronary Artery Bypass-Case Report-

A 63-year-old man presented with subclavian steal syndrome associated with left internal mammary artery (IMA) bypass graft to a coronary artery. He was admitted with a history of oppressive sensation in the chest, dizziness, and light headedness on exertion for 2 weeks in March 2002. He had undergone myocardial revascularization consisting of a left IMA-to-left anterior descending coronary artery graft in April 1988. His blood pressure was 140/70 mmHg in the right arm and 80/64 mmHg in the left arm. Aortic arch arteriography revealed complete occlusion of the left subclavian artery proximal to the left IMA takeoff and subclavian steal with anterograde flow of the left IMA. Percutaneous angioplasty and stent placement with protection of the left IMA bypass graft using a balloon catheter was successfully performed without complication by cerebral or myocardial ischemia. Complete recanalization of the occluded left subclavian artery and anterograde flow of the left vertebral artery were achieved. His symptoms disappeared and blood pressure in the left arm recovered. This variant of coronary subclavian steal might require protection of the left IMA during angioplasty and stent placement.

Unprotected carotid artery stenting compared to carotid endarterectomy in a community setting

PURPOSE

To evaluate the feasibility and safety of carotid artery stenting (CAS) performed by a dedicated multidisciplinary team in a community hospital.

METHODS

Forty-nine patients (30 men; mean age 74.3 +/- 7.4 years, range 51-88) with 14 symptomatic and 35 asymptomatic >50% carotid stenoses were enrolled into the study and treated with self-expanding stents without cerebral protection. The patients were evaluated at 30 days for death, neurological sequelae, and length of stay. A contemporaneous group of 140 patients (80 men; mean age 72.3 +/- 7.7 years, range 43-89) undergoing carotid endarterectomy (CEA) was used for comparison of the outcome measures. Owing to crossover of failed CAS patients to the CEA group, the data were analyzed according to intention-to-treat and treatment-received.

RESULTS

The only difference in baseline characteristics between the treatment and control groups was the greater frequency of bilateral disease in the CEA group (p=0.009). The CAS procedures were successful in 47 (96.0%) patients; 2 access failures were converted to endarterectomy, and 1 access-site pseudoaneurysm was treated surgically. There were no deaths or myocardial infarctions in either group. In the CAS group, there were no major and only 2 (4.1%) minor strokes compared to 4 (2.9%) major and 4 (2.9%) minor strokes in the CEA group (p>0.05). Median LOS was significantly lower in the CAS group (p<0.0001).

CONCLUSIONS

Careful case selection and multidisciplinary collaboration facilitate the safe performance of carotid stenting in a community setting with acceptable early results.

Vertebral artery stenting

The safety and efficacy of endoluminal stenting in treating atherosclerotic vertebral artery disease was evaluated in 38 vessels in 32 patients. Indications for revascularization included diplopia (n = 4), blurred vision (n = 4), dizziness (n = 23), transient ischemic attacks (n = 4), drop attack (n = 1), gait disturbance (n = 1), headache (n = 2), and asymptomatic critical stenosis (n = 1). Success (< 20% residual diameter stenosis, without stroke or death) was achieved in all 32 patients (100%). One patient experienced a transient ischemic attack (TIA) 1 hr after the procedure. At follow-up (mean, 10.6 months), all patients (100%) were alive and 31/32 (97%) were asymptomatic. One patient (3%) had in-stent restenosis at 3.5 months and underwent successful balloon angioplasty. Endoluminal stenting of vertebral artery lesions is safe, effective, and durable as evidenced by the low recurrence rate. Primary stent placement is an attractive option for atherosclerotic vertebral artery stenotic lesions. Cathet Cardiovasc Intervent 2001;54:1-5.

Percutaneous treatment of symptomatic vertebral artery stenosis with coronary stents

Atherosclerotic disease of the vertebral artery can pose a significant clinical problem. The treatment of that disease is not uniformly accepted. We report two cases of patients with vertebral basilar insufficiency due to stenosis of the vertebral artery origins and contralateral occlusions that were treated percutaneously with coronary stent placement.

Prevention and treatment of thromboembolic and ischemic complications associated with endovascular procedures: Part II--Clinical aspects and recommendations

We reviewed the incidence, risk factors, and clinical features of thromboembolic and ischemic events associated with diagnostic cerebral angiography, endovascular treatment of aneurysms using coils or balloons, angioplasty and stent placement to treat extracranial carotid artery stenosis, and embolization of arteriovenous malformations using glue or other embolic agents. We performed a cumulative analysis to determine the frequency and characteristics of these events and a subset analysis (whenever possible) to determine the benefits of various strategies for complication avoidance. Of the 1,547 patients who underwent Guglielmi detachable coil treatment, thromboembolic events were observed for 127 (8.2%), consisting of asymptomatic events for 12 patients, transient ischemic attacks for 29, and strokes for 86. The outcomes for the 86 patients with strokes were categorized as full recovery for 15, good recovery for 27, partial recovery for 19, no recovery for 11, death for 12, and undetermined outcome for 2. Of the 834 patients who underwent carotid angioplasty and stent placement, thromboembolic events were observed for 73 (8.8%), consisting of transient ischemic attacks for 26 patients and strokes for 47. The outcomes for the patients with strokes were categorized as full recovery for 20, good recovery for 15, partial recovery for 6, no recovery for 2, and death for 4. High rates of thromboembolic events were also observed with balloon occlusion of aneurysms (11%) or parent arteries (19%) and carotid angioplasty alone (5.9%). Arteriovenous malformation embolization was associated with an ischemic event/procedure rate of 9.4%. High rates of thromboembolic and ischemic complications, with subsequent morbidity and death, are associated with most endovascular procedures. Further research and the formulation of standard preventive guidelines may help to reduce these risks and improve the overall success of these procedures.

Identification of patients at risk for periprocedural neurological deficits associated with carotid angioplasty and stenting

BACKGROUND AND PURPOSE

Transient or permanent neurological deficits can occur in the periprocedural period following carotid angioplasty and stenting (CAS), presumably due to distal embolization and/or hemodynamic compromise. We performed this study to identify predictors of neurological deficits associated with carotid angioplasty and stent placement.

METHODS

We reviewed medical records and angiograms in a consecutive series of patients who underwent CAS for symptomatic or asymptomatic cervical internal carotid artery stenosis from June 1996 through December 1998. Using logistic regression analysis, we evaluated the effect of demographic, clinical, intraprocedural, and angiographic risk factors on subsequent development of periprocedural neurological deficits. Periprocedural neurological deficits were defined as new or worsening transient or permanent neurological deficits that occurred during or within 48 hours of the procedure.

RESULTS

A total of 111 patients (mean age 68.2+/-9.1 years) who underwent CAS for asymptomatic (n=54) or symptomatic (n=57) stenoses were included in this study. A total of 14 periprocedural neurological deficits (13%) were observed either during (n=4) or after (n=10) the procedure. Three identified variables were independently associated with periprocedural neurological deficits: symptomatic lesion (OR 8.3, 95% CI 1.6 to 42.6), length of stenotic segment >/=11.2 mm (OR 5.2, 95% CI 1.2 to 22.5), and absence of hypercholesterolemia (OR 5.4, 95% CI 1.4 to 20.9). Other variables, including age and degree of stenosis (defined by NASCET criteria), were not associated with periprocedural neurological deficits.

CONCLUSIONS

A combination of clinical and angiographic variables can be used to identify patients at risk for periprocedural neurological deficits after CAS. Such identification may help in selection of patients who may benefit from novel pharmacological and mechanical preventive approaches.

Extracranial vertebral artery stent placement: in-hospital and follow-up results

OBJECT

The authors summarize their experience with stent deployment in the treatment of vertebrobasilar artery (VBA) insufficiency. This is an underdiagnosed condition, and the incidence of significant vertebral artery (VA) stenosis has been underappreciated. Medical therapy has been the mainstay of treatment because of the high rate of morbidity associated with surgical correction of VA stenosis. Recently, some authors have reported acceptable results with the use of percutaneous transluminal angioplasty, but this technique has significant weaknesses such as elastic recoil and problems in achieving safe treatment of dissections.

METHODS

The authors investigated the feasibility, safety, and outcome of VA stent placement in 50 patients in whom 55 vessels were treated using stents. Technical success was achieved in 54 (98%) of 55 vessels, with no procedure-related complications. However, one patient (2%) died of nonneurological causes, and one (2%) suffered a stroke that occurred within the 30-day postprocedural period and was related to a complicated coronary intervention. Clinical follow-up review performed at a mean of 25 +/- 10 months revealed two patients (4%) with recurrence of VBA symptoms. Six-month angiographic follow up was completed in 90% of eligible patients, with a 10% incidence of restenosis as defined by greater than 50% luminal narrowing.

CONCLUSIONS

Vertebral artery stent placement is feasible in patients who have significant VA stenosis, with predictably good angiographically demonstrated and clinical results. The 6-month angiographically confirmed restenosis rate appears to be low, as does the clinical recurrence rate. This technique solves the problems of elastic recoil and the treatment of angioplasty-induced dissections. Further prospective comparison with medical preventive strategies is warranted.

Percutaneous revascularization of atherosclerotic obstruction of aortic arch vessels

OBJECTIVES

To compare stenting of aortic arch vessel obstruction with surgical therapy and to establish recommendations for treatment.

BACKGROUND

Though surgery has been considered to be the procedure of choice for subclavian and brachiocephalic obstruction, little work has been done to compare it with stenting.

METHODS

Eighteen patients with symptomatic aortic arch vessel stenosis or occlusion were treated with stenting, followed by periodic clinical follow-up and noninvasive arterial Doppler studies. Data were compared with the results as shown in a systematic review of a published series of surgery and stenting procedures which included comparison of technical success, complications, mortality and patency.

RESULTS

Primary success in our series was 100% with improvement in mean stenosis from 84+/-11% to 1+/-5% and mean arm systolic blood pressure difference from 44+/-16 mm Hg to 3+/-3 mm Hg. There were no major complications (death, stroke, TIA, stent thrombosis or myocardial infarction). At follow-up (mean 17 months), all patients were asymptomatic with 100% primary patency. Literature review demonstrates equivalent patency and complications in the other published series of stenting. In contrast, there was a similar patency but overall incidence of stroke of 3+/-4% and death of 2+/-2% in the published surgical series.

CONCLUSIONS

Subclavian or brachiocephalic artery obstruction can be effectively treated by primary stenting or surgery. Comparison of stenting and the surgical experience demonstrates equal effectiveness but fewer complications and suggests that stenting should be considered as first line therapy for subclavian or brachiocephalic obstruction.

Treatment of Restenosis after PTA for Internal Carotid Stenosis

SUMMARY

Thirteen cases of restenosis occurred after percutaneous transluminal angioplasty (PTA) in 63 cases of internal carotid stenoses. They were treated by PTA or carotid endarterectomy. The patients were sufficiently informed of each treatment. Seven of them were initially treated by repeated PTA. The stenosis ratio improved from 82% to 30% after repeated PTA on average. However, one case in the PTA treated group resulted in restenosis and then carotid endarterectomy was performed. The other case also caused restenosis and was treated by PTA. Six cases were initially treated by carotid endarterectomy and all cases were successfully treated without difficulty. The success rate of the PTA was 2/7 (29%) in restenosis cases. One case causing re-restenosis had severe calcification in the arterial wall. PTA was thought to be effective for the restenosis cases after initial PTA if the arterial calcification was not severe.

Carotid angioplasty

BACKGROUND

Carotid angioplasty with stenting (PTAS) is now being investigated as an alternative to carotid endarterectomy (CEA). Proven superiority in at least three areas of PTAS will need be accomplished before angioplasty supplants CEA; namely, safety, cost, and durability.

METHODS

One hundred and seven patients served as the basis for this previously reported review. Both safety (morbidity and mortality) as well as cost issues were evaluated. Other non-neurologic complications were are also investigated.

RESULTS

The in-hospital and 30-day risk of all strokes and death from PTAS was 9.3%, with a 3.6% major stroke and death rate. Minor strokes were found to be statistically more frequent in the PTAS group than with CEA. Nonprofessional fees were more expensive in the PTAS group than CEA ($30,140 versus $21,670).

CONCLUSIONS

At the present time PTAS has not proven itself worthy to supplant CEA. The durability of the procedure has not been sufficiently evaluated. Non-neurologic complications are also not trivial with PTAS.

Innominate artery reconstruction: over 3 decades of experience

SUMMARY BACKGROUND DATA

Symptomatic atherosclerotic occlusive disease of the innominate artery is a threatening disease pattern that offers a major challenge in achieving definitive surgical repair. To assess the evolution of treatment strategies and their outcomes for this disease, the authors undertook a review of the cumulative experience for more than 3 decades at one institution.

METHODS

Between 1960 and 1997, 94 patients (mean age, 62 years) underwent direct innominate artery revascularization for occlusive atherosclerotic disease to relieve neurologic (n = 85) and/or right upper extremity (n = 26) symptoms or asymptomatic critical stenosis (n = 3). The pattern of atherosclerotic involvement revealed by angiography included critical stenosis (n = 77), complete occlusion (n = 10), and moderate stenosis with plaque ulceration (n = 7). A common brachiocephalic trunk was present in five patients. Transsternal (n = 68) or transcervical (n = 4) innominate endarterectomy was performed in 72 patients and bypass grafting in 22. Forty-one patients underwent concomitant endarterectomy or bypass of innominate branches or adjacent arch vessels, and 3 had coronary bypass grafting.

RESULTS

There were three perioperative deaths (3%), all due to cardiac causes. Postoperative morbidity included four strokes (three resolved), two myocardial infarctions, two transient ischemic attacks, and one sternal dehiscence. Follow-up ranged from 8 months to 20 years. Postoperative actuarial survival rate was 96% at 1 year, 85% at 5 years, and 67% at 10 years. Freedom from recurrence requiring reoperation was 100% at 1 year, 99% at 5 years, and 97% at 10 years.

CONCLUSIONS

Innominate artery reconstruction is safe and durable when either endarterectomy or prosthetic bypass is used. The anatomic variation and disease distribution permit endarterectomy for most patients. The technique of innominate endarterectomy can be extended safely to outflow and adjacent vessels.

Feasibility of intraoperative balloon angioplasty and additional stent placement of isolated stenosis of the brachiocephalic trunk

OBJECTIVE

We sought to evaluate the feasibility and results of intraoperative balloon angioplasty and additional stent placement of isolated stenosis of the brachiocephalic trunk.

PATIENTS AND METHODS

Between May 1993 and October 1996, we treated eight patients with local stenosis of the innominate artery. Seven lesions were situated in the proximal and one in the middle third of the brachiocephalic trunk. Five patients were men and three were women, with ages ranging from 55 to 72 years (mean 59.5 years). All stenoses provoked severe blood flow reduction and caused clinical symptoms. Procedures were performed in an operating suite with fluoroscopic imaging capabilities. Through an anterolateral cervical approach the right common carotid artery was surgically exposed and then clamped to avoid atheroembolization during the subsequent procedure. Retrograde catheterization was performed to reach the stenosis of the brachiocephalic trunk. The lesion was dilated with a balloon catheter and successively stented. Follow-up examinations (color-coded duplex sonography, accompanied by clinical inspection and systolic blood pressure) were scheduled every 6 months.

RESULTS

In all patients the dilation of the stenosis of the innominate artery and the stent placement were successful without any side effects. No embolic events or other complications occurred. The postintervention angiography showed successfully dilated stenoses and patent stents in all cases. The technical success rate was 100%.

CONCLUSIONS

On the basis of our preliminary data, we believe that, in selected patients, intraoperative balloon angioplasty of stenosis of the innominate artery with stent placement from the right common carotid artery approach is a safe and effective alternative to conventional operations.

Thrombolysis and angioplasty for acute occlusion of intracranial vertebrobasilar arteries. Report of three cases

Three cases of intracranial vertebrobasilar occlusion were successfully treated in the acute stage by thrombolysis and angioplasty. All three patients were admitted to the hospital because of consciousness disturbance and other brainstem signs. Initial angiography revealed intracranial vertebrobasilar occlusions. At first, a microcatheter was introduced into the distal site of the occlusion and thrombolysis was attempted by using urokinase. Recanalization was achieved in all cases but severe stenosis of the intracranial vertebral and basilar arteries was found. The recanalization was followed by transluminal balloon angioplasty and the stenosis was successfully resolved. Marked neurological improvement was achieved in each case. Follow-up cerebral angiography demonstrated sufficient patency at the angioplasty site after 3 to 6 months. Residual severe stenosis of vertebrobasilar arteries after thrombolytic therapy carries the possibility of reocclusion. Combining angioplasty with thrombolysis to avoid rethrombosis and obtain sufficient distal blood flow is of significant benefit in treating vertebrobasilar occlusion.

Angioplasty of Acute Occluded Cerebral Arteries

22 cases of stenosed or occluded cerebral arteries were treated by percutaneous transluminal angioplasty (PTA) in acute stage. There were 10 internal carotid lesions, 4 middle cerebral artery lesions, 5 intracranial vertebral artery lesions, and 3 basilar artery lesions. 14 cases were treated for residual stenosis after recanalization using urokinase.

Successful dilatation (over 50%) was achieved in 16 cases (73%). 3 lesions were inaccessible due to atherosclerotic change. There were no major complications. Restenosis was observed in 4 internal carotid lesions and 1 middle cerebral lesion. 7 (50%) cases with internal carotid lesions and 5 (63%) cases with vertebrobasilar lesions returned to their previous life.

The results suggest that PTA in acute stage is feasible for occlusive disease of cerebral arteries.

Innominate artery occlusive disease: management with central reconstructive techniques

BACKGROUND

The purpose of this study was to review our experience with central vascular reconstruction for innominate artery occlusive disease. Eighteen patients underwent central reconstruction for innominate artery (IA) occlusive disease during an 8-year period (1986 to 1994). Mean age was 59 years (range, 36 to 77 years). Women outnumbered men 12 to 6. All patients had symptoms including amaurosis fugax 55%, transient ischemic attacks 44%, vertebrobasilar insufficiency 44%, and arm claudication 33%. The IA was occluded in three patients and stenotic in 15. Three patients underwent previous extrathoracic bypass procedures for IA lesions that failed.

METHODS

Operations performed through a median sternotomy included aortocarotid bypass with reimplantation of the subclavian (n = 10) and aortoinnominate bypass (n = 7). Transection and oversewing of the IA was performed in all but one patient, in whom ligation of the IA was performed. One patient with severe chronic obstructive pulmonary disease and previous coronary artery bypass grafting underwent retrograde-transluminal IA angioplasty with endovascular stent placement via a carotid approach. Four patients underwent concomitant carotid endarterectomy). Two patients underwent concomitant coronary artery bypass grafting at the time of IA reconstruction.

RESULTS

There was one operative death from myocardial infarction. Perioperative morbidity included dysrrhythmia (three), respiratory insufficiency (three), subendocardial myocardial infarction (two), cerebrovascular accident with complete recovery (two), hemorrhage (one), and acute graft occlusion (one). All grafts remained patient at a mean follow-up of 21 months (range, 8 to 60 months). The only patient who underwent ligation of the IA required a subsequent revision of the IA to transection and oversewing for an embolic event at 4 months status-post aortocarotid bypass. The patient who underwent angioplasty remained asymptomatic with a patient IA at 12 months. Average length of stay for transthoracic repair was 14 days and for transluminal angioplasty 2 days.

CONCLUSIONS

Innominate artery bypass based on the ascending aorta is effective in providing relief of symptoms and has a high patency rate. Because of the significant morbidity, these procedures should be reserved for patients with symptoms. The IA should be transected and oversewn to prevent recurrent embolism. Transcarotid, retrograde angioplasty provides an alternative approach to stenotic lesions located in the IA or proximal common carotid artery. An aggressive approach directed at defining coronary artery disease is an invaluable adjunct to the proper treatment of this patient population.

Asymptomatic carotid stenosis in patients undergoing major cardiac surgery: can percutaneous carotid angioplasty be an alternative?

OBJECTIVE

As the mortality associated with coronary artery bypass grafts has fallen, morbidity has become an increasing problem. The improvement of transluminal carotid angioplasty is enlarged to patients with asymptomatic severe carotid stenosis (> 85%) requiring coronary surgery.

METHODS

Between January 1993 and January 1995, 10 patients underwent percutaneous carotid angioplasty prior to cardiac surgery (17.4 days). Mean age was 71 +/- 4.3 years. Four patients showed a contralateral occlusion of the internal carotid artery. Transluminal carotid angioplasty was carried out with a triple coaxial catheter system. Six angioplasties required a Strecker stent.

RESULTS

Mean follow-up was 11.4 months. No mortality was observed. Only one patient showed a transient hemianopsia. All patients underwent angiography at four months. Two patients required a new procedure of carotid angioplasty completed with a Strecker stent in one case and by dilatation of a stent in another patient.

CONCLUSION

The results of transluminal carotid angioplasty, in this short series, are encouraging in this group of high-risk morbidity and mortality (elderly patients, bilateral carotid lesions, multiple coronary arterial grafts).

Brachial artery approach for transluminal angioplasty of the internal carotid artery

One possible problem in internal carotid angioplasty is inaccessibility of the lesion due to elongation of the aortic arch, the brachiocephalic trunk, or the carotid artery itself. A new approach to performing angioplasty of the right or left internal carotid artery utilizing the brachial artery was used after failure of the transfemoral approach in 5 lesions (4 patients). The common carotid artery was cannulated with performed 5F catheters. Angioplasty was performed with a conventional balloon dilatation catheter. If required, a Wall stent was implanted to optimize the angiographic result. After failure of the conventional transfemoral technique, the brachial technique permitted successful angioplasty of the ipsilateral internal carotid artery in 4 lesions and the contralateral internal carotid artery in 1 lesion. In 1 patient, a stent was implanted. No complications occurred. The mean stenosis diameter decreased from 77.8 +/- 6.3% to 17.8 +/- 9.1%. Doppler sonography performed 4-6 months later showed no restenosis. The brachial artery approach seems to be a suitable alternative to the femoral technique.

Techniques for endovascular recanalization of supra-aortic trunks

The supra-aortic are no stranger to endovascular interventions. Since the 1980s, interventionists have been evaluating and refining the use of transluminal techniques for recanalizing stenotic and occlusive lesions in these large-bore, high-flow vessels. The authors present their methodologies for evaluating, selecting, and treating supra-aortic lesions with balloon angioplasty and stenting. Helpful suggestions are offered for optimizing the outcome of these endovascular approaches to atherosclerotic occlusive disease in the supra-aortic trunks.

Use of coronary Palmaz-Schatz stent in the percutaneous treatment of vertebral artery stenoses

A case of chronic vertebrobasilar insufficiency due to severe stenoses at the origins of both vertebral arteries was treated with percutaneous transluminal angioplasty and coronary Palmaz-Schatz stents. Use of stents led to a better angiographic result than angioplasty alone. The patient is improved 8 mo later.

Use of coronary Palmaz-Schatz stent in the percutaneous treatment of an intracranial carotid artery stenosis

A 69-yr-old man had chronic transient ischemia attacks due to severe stenosis of the intracranial portion of the right carotid artery. After failure of both antiplatelet and anticoagulant therapy, treatment was successful with percutaneous transluminal angioplasty and a coronary Palmaz-Schatz stent. Use of the stent led to a better angiographic result than angioplasty alone. The patient is asymptomatic 4 mo later.

Complications associated with extracranial carotid artery interventions

Efforts to ameliorate the tremendous personal and financial ramifications of stroke in this country have focused on the recently validated stroke reduction potential of carotid endarterectomy. During the years in which numerous randomized trials compiled their evidence in favor of surgical treatment, the evolution of minimally invasive therapeutic alternatives to surgery spread to encompass nearly every vascular bed in the body. Only the fragile cerebrovascular system remains as the final challenge for interventionists. Any revascularization alternative to carotid endarterectomy should achieve the same initial and long-term outcomes as the surgical gold standard, with comparable morbidity and mortality. After years of cautious, circumspect application, carotid angioplasty is now a contender for this role. Assisted by the newer stent technology, minimally invasive carotid interventions are entering clinical trials. While it is premature to discuss the stroke reduction potential of these catheter-based techniques, it is imperative that we recognize and prepare to treat the myriad, sometimes catastrophic, complications of these therapeutic approaches to carotid obliterative disease.

Vertebral artery stenting following percutaneous transluminal angioplasty. Technical note

The authors report initial results and follow up using stent placement to treat atherosclerotic stenosis in vertebral arteries. Three patients with severe atherosclerotic vascular disease underwent vertebral artery stent placement using a balloon expandable stent. Medical therapy (aspirin and warfarin) and conventional percutaneous angioplasty failed to resolve the disease and the patients developed symptomatic restenosis within 3 months of angioplasty. Two patients had symptoms of anterior circulation ischemia with carotid artery occlusions and reduced supply to the anterior circulation from the stenosed vertebral arteries. One patient had recurrent posterior circulation symptoms. Stents were successfully placed in all three, resulting in immediate reversal of stenosis and resolution of symptoms. Clinical follow-up study (mean 9 months) has shown no recurrent symptoms in the patient with posterior circulation symptoms, but the two patients with anterior circulation ischemia did develop recurrent symptoms. Angiographic follow up in these two patients at 3 months and 1 year, however, demonstrated continued patency of vertebral artery lumina. They underwent extracranial-intracranial bypass surgery to relieve their symptoms. This experience suggests stents can be placed without complication in the proximal vertebral arteries and may have an adjunctive role in the treatment of atherosclerotic cerebrovascular disease following unsuccessful angioplasty.

Results of balloon angioplasty in the carotid arteries

PURPOSE

To report the experiences to date with percutaneous transluminal angioplasty (PTA) of the carotid artery and other supra-aortic vessels. A new coaxial dilatation system for carotid angioplasty with temporary balloon occlusion to avoid cerebral embolization is presented.

METHODS

PTA was performed in 220 patients with 245 stenosed or occluded supra-aortic arteries; among these were 74 carotid stenoses in the proximal common (n = 5), distal common (n = 1), internal (n = 65), and external (n = 3) carotid arteries. Duplex and B-mode ultrasonography, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, indium 111-labeled platelet scintigraphy, and/or angiography were used before and after PTA. Intravascular ultrasound imaging was also recently added for monitoring angioplasty results.

RESULTS

All patients but one with carotid lesions had symptoms of cerebrovascular insufficiency. Angioplasty was successful in 69 of the 74 carotid stenoses: proximal common (n = 5), distal common (n = 1), internal (n = 60), and external (n = 3). There were only 1 major (hemiparesis) and 2 minor complications. During the average 70-month observation period, restenosis has not occurred in any treated carotid artery. In a literature review of > 500 patients undergoing carotid angioplasty, the complication rate appears very low (mortality 0%; morbidity 2.1%) and comparable to that for carotid endarterectomy.

CONCLUSIONS

Results of this review suggest that percutaneous transluminal angioplasty of the carotid artery is an effective alternative method to vascular surgery, particularly for patients with comorbidities that elevate the risks of surgery.