Intracranial Angioplasty and Thrombolysis

Intra-arterial thrombolysis in acute ischemic stroke: a review of pharmacologic approaches

Ischemic stroke is a major public health problem worldwide. The potential to cure stroke patients with intravenous thrombolytic therapy has evolved to the use of intra-arterial thrombolytic agents. Fewer than 200 patients have been enrolled in randomized trials of intra-arterial therapy. In this article the authors have reviewed the literature listed in MEDLINE and EMBase, and searched relevant articles to examine the role of fibrinolytic agents in acute interventional stroke therapy. Only English language articles reporting five or more patients were included. Outcomes were defined at 90 days. Good outcome was defined on the modified Rankin Scale. Symtpomatic hemorrhage was defined as hemorrhage in the setting of clinical deterioration in the first 24 to 48 h. The search identified 57 studies of which 44 reported usable data. Only three randomized trials were reported. Of a total of 1140 patients, most (73%) were treated open-label with urokinase (Abbokinase, Abbott Laboratories). The best outcomes were reported in case series and slightly worse outcomes were reported in clinical trials. Overall, it was not possible to distinguish whether one agent was superior to the others. There is a paucity of published evidence on intra-arterial therapy for acute ischemic stroke. Alteplase (Activase, Genentech Inc.) is currently the drug of choice simply because it is available and it is the current intravenous standard. Further trials and developments are anticipated.

The endovascular operating room as an extension of the intensive care unit: changing strategies in the management of neurovascular disease

Technological advances within the field of endovascular neurosurgery have influenced the management of the neurovascular patient within the intensive care unit (ICU). The endovascular operating room has, in fact, become an extension of the ICU in certain cases. Given the rapid development of new endovascular technologies, it is more important than ever for neurosurgeons to remain intimately involved with the care of their patients within the ICU. This article offers an overview of the evolution in ICU management of neurovascular disease and provides a framework for the incorporation of the endovascular operating room in the intensive care management of patients with this disease.

Use of stents to treat intracranial cerebrovascular disease

Intracranial atherosclerosis is a common cause of stroke. Although it has been recognized for decades, the lack of successful treatment strategies has limited clinical interest until recently. We review the natural history and pathophysiology of intracranial atherosclerosis. Vascular biomechanics are important to define differences between cerebral arteries and extracranial vessels and partly explain the technical challenges facing cerebral artery revascularization as compared with revascularization of coronary arteries. Pharmacological interventions to prevent stroke have had limited success, but technological developments offer improved methods for endovascular revascularization of symptomatic and asymptomatic cerebral artery stenosis. Identification of appropriate candidates for treatment also remains a challenge, and our knowledge about the natural history of the disease is limited. At this time, patients with significant intracranial stenosis should receive information on the benefits and risks of revascularization therapy. Determining which patients should undergo revascularization procedures will require carefully planned, randomized clinical trials.

Effect of intraarterial verapamil on the diameter of vasospastic intracranial arteries in patients with cerebral vasospasm

Object

This study was conducted to determine whether there is a change in intracranial arterial diameters after verapamil infusion for vasospasm and, if it is present, to determine whether the change occurs in proximal, intermediate, or distal vessels.

Methods

The authors measured arterial diameters in all patients treated with intraarterial verapamil at their institutions between August 2003 and September 2004. In all, 18 treatments were examined in 15 patients. Measurements were made before and after verapamil infusion in a blinded fashion with the aid of a magnification loupe at nine predetermined arterial sites on each angiogram. Baseline arterial measurements were made on each patient's initial angiogram and on the angiogram demonstrating spasm prior to endovascular therapy as well in 14 of the patients. Charts were retrospectively reviewed to determine whether the patients benefited from intraarterial vera-pamil.

From the time of the initial angiogram to the time of vasospasm, there was a 21.6% decrease (p = 0.092) in proximal artery diameter, a 47.1% decrease (p < 0.05) in intermediate artery diameter, and a 12.4% decrease (p < 0.05) in distal artery diameter. There were no significant changes in the diameters of proximal, intermediate, or distal vessels after verapamil infusion (mean dose 7.4 mg, range 2.5–10 mg). After infusion of intraarterial verapamil, the proximal vessels showed a 1.1% decrease in diameter, the intermediate vessels showed a 9.4% increase, and the distal vessels showed a 3.3% decrease.

Conclusions

Administration of intraarterial verapamil does not cause a significant increase in the diameter of vasospastic vessels at the administered doses.

Current endovascular treatment options for intracranial carotid artery atherosclerosis

A substantial number of strokes are caused by intracranial atherosclerosis, a disease that traditionally has been treated medically. Recent technological advancements, however, have revolutionized the treatment of this condition by enabling the use of endovascular methods. In this paper the authors focus on the internal carotid artery, and review relevant studies concerning angioplasty with stent placement for the management of intracranial atherosclerosis in this vessel. With continued experience and a multidisciplinary approach in the evaluation of these patients, favorable outcomes may be achieved.

Intracranial Revascularization Therapy: Angioplasty and Stenting

Depending on the population studied, intracranial atherosclerosis accounts for 10% to 29% of ischemic brain events. A significant number of patients with intracranial atherosclerosis continue to suffer from repeated strokes or transient ischemic attacks despite optimal medical management. In selected patients, intracranial angioplasty with or without stenting is a promising treatment option. Patient selection, careful periprocedural medical management, and a highly skilled neuroendovascular interventionalist are required in order to perform the procedure with an acceptable risk.

Intracranial Angioplasty and Stent Placement for Cerebral Atherosclerosis

Intracranial atherosclerotic stenoses have been estimated to account for 8%-10% of all ischemic strokes. A substantial number of patients fail the best medical treatment, which includes control of vascular risk factors and administration of antithrombotics (platelet-active drugs or warfarin), statins, and angiotensin-converting enzyme inhibitors. In these patients, angioplasty with stent placement is one reasonable treatment option for preventing massive ischemic stroke. Herein, we discuss basic pathophysiologic concepts and their effect on endovascular revascularization procedures.

Indications for endovascular therapy for refractory vasospasm after aneurysmal subarachnoid hemorrhage: experience at the University of Cincinnati

BACKGROUND

Transluminal balloon angioplasty (TBA) and intra-arterial papaverine (IAP) appear to be valuable alternatives for the treatment of aneurysmal subarachnoid hemorrhage (SAH)-induced vasospasm refractory to maximal medical therapy. Although widely used, guiding principles for the implementation of TBA and IAP are not yet established. Based on our retrospective analysis, we define guidelines for endovascular therapy for refractory vasospasm based on our clinical results, adverse effects, and pattern of vasospasm.

METHODS

Medical records of 62 patients who experienced aneurysmal SAH-induced vasospasm refractory to hypervolemic, hypertensive, hyperdynamic therapy, and who were treated with IAP or TBA were reviewed. Fifty patients met the inclusion criteria for analysis. After careful scrutiny, two types of responses to endovascular treatment were identified. On the basis of that grouping, patients were divided into two groups according to the number of arterial segments involved, that is, monoterritorial and multiterritorial vasospasm. Multiple variables were analyzed.

RESULTS

Patients undergoing multiple endovascular procedures exhibited the worst outcomes. Patients in the monoterritorial group experienced a higher incidence of clinical improvement and better outcomes after endovascular treatment. Elevated intracranial pressure (ICP) and ICP-related deaths were more prominent in the multiterritorial group of patients. Sustained ICP elevation after administration of IAP was strongly associated with poor outcome in the multiterritorial group.

CONCLUSIONS

IAP is indicated as an early potential single-dose infusion in distal monoterritorial vasospasm, if angioplasty is impossible or unsafe. The use of IAP in bilateral diffuse vasospasm is discouraged because of the high susceptibility of these patients to develop elevated ICP. Multiple IAP infusions seem to have no significant impact on patient outcome. Balloon angioplasty seems to be indicated at an early juncture in patients with multiterritorial proximal vasospasm.

Provisional stenting for symptomatic intracranial stenosis using a multidisciplinary approach: acute results, unexpected benefit, and one-year outcome

Percutaneous techniques have dramatically changed our approach to coronary and peripheral revascularization. Intracranial atherosclerosis is a highly morbid disease; however, techniques for revascularization are still in evolution. The authors comprise a multidisciplinary team of neurologists, neuroradiologists, and interventional cardiologists who have collaborated in treating fifteen patients with symptomatic intracranial stenosis who have failed medical therapy. The acute success rate (100%) and one-year freedom from death and stroke (93.4%) using balloon angioplasty and provisional stenting are encouraging. A surprising observation in this patient cohort was that 53% of patients had improvement or resolution of a deficit that was chronic and presumed to be permanent and irreversible. This type of chronic but reversible deficit is termed "brain angina". The background, rationale for a multidisciplinary team, techniques, and preliminary results of intracranial angioplasty with provisional stenting are presented.