AHA/ASA issues guidelines on intracranial neurointerventional procedures

Susan Jeffrey

April 09, 2009

Dallas, TX- New guidelines from the AmericanHeartAssociation/AmericanStrokeAssociation examine the evidence to support neurointerventional procedures in the gamut of intracranial cerebrovascular conditions, ranging from acute ischemic stroke, to ruptured and unruptured aneurysms, to intracranial stenosis and arteriovenous malformations [1].

"It's important to track the levels of evidence as this specialty evolves," said Dr Philip M Meyers (Columbia University College of Physicians and Surgeons, NY), who chaired the writing committee for the new document.

"This is a timely endeavor," Meyers added. "As the government reviews healthcare costs, there is an emphasis on efficacy at [the Centers for Medicare and Medicaid Servic es]. Consequently, there is great interest in understanding the state of the art for endovascular treatment of cerebrovascular disease," he said.

The document was published online April 6, 2009 in Circulation.

Emerging issues

The clinical area of endovascular intervention is an evolving one and has given rise to a number of controversial issues, including who should perform these procedures, how operators should be trained and accredited, and how outcomes with endovascular procedures compare with standard open procedures or with conservative medical management. The aim of the new guideline is to address some of these issues and to provide an assessment of the best evidence to date supporting endovascular neurointerventional procedures.

The publication is the result of three years of collaboration among the range of neuroscience professionals with interest in these procedures. The writing group was composed of neurointerventionalists, neurosurgeons, and neurologists, as well as a vascular medicine specialist and an interventional radiologist. The document then underwent multidisciplinary review by medical and interventional cardiologists, who had an opportunity to express their perspective.

When discussing accreditation, for example, the document points out that since 2000, an Accreditation Council for Graduate Medical Education (ACGME)-approved training curriculum has been available. However, the writing group acknowledges that "several nonneurologically based endovascular subspecialties, such as vascular medicine, vascular surgery, and interventional cardiology, perform stent placement with neuro-rescue via alternative (ACGME) pathways, as well as a clinical practice pathway."

In terms of clinical recommendations, one area where the evidence for endovascular intervention has become fairly strong is in the treatment of ruptured cerebral aneurysms, Meyers noted. Data on the comparative efficacy of endovascular coil occlusion vs surgical clipping from the International Subarachnoid Aneurysm Trial, for example, have provided randomized evidence supporting the use of endovascular coils as a viable alternative to open surgical clipping in selected cases.

Less clear is the evidence supporting the use of endovascular interventions in the setting of acute ischemic stroke, Meyers said. The use of retrieval devices, such as the Concentric Merci and Penumbra systems, has been approved by the US Food and Drug Administration; it is not clear at this time that clot retrieval improves clinical outcomes, although limited evidence suggests this might be true, he added. Similarly, the use of intracranial stents is still under investigation, although they might provide a viable approach to treatment of intracranial stenosis.

"A document like this gets at the heart of the data and how we separate fact from enthusiasm or expectation," he said. "I believe it establishes a baseline from which we can then build over time."

The following are some of the main recommendations in the new document.

  • Ruptured aneurysms Endovascular coil occlusion of the aneurysm is appropriate if the aneurysm is deemed treatable by either endovascular coiling or surgical clipping (class I, level of evidence B).

  • Unruptured aneurysms The authors deem it "reasonable" to consider endovascular occlusion for unruptured aneurysms if the aneurysm is thought to require intervention over conservative management and is amenable to endovascular treatment according to an endovascular specialist (class IIa, level of evidence B).

  • Intracranial stenosis—For symptomatic atherosclerotic stenosis greater than 70% and failing medical therapy, endovascular revascularization with angioplasty or stenting might be reasonable (class IIb, level of evidence B).

  • Acute ischemic stroke For patients with a major stroke syndrome lasting six hours or less who are either ineligible for or who have failed intravenous thrombolysis, it is "reasonable to consider intra-arterial thrombolysis in selected patients" (class I, level of evidence B). For patients with a major stroke syndrome lasting eight or more hours, it "may be reasonable" to use mechanical disruption to restore blood flow in selected patients (class IIb, level of evidence B).

  • Cerebral arteriovenous malformation (AVM)For patients with hemorrhage referable to a pial AVM, endovascular treatment in combination with other therapies, such as surgery or radiosurgery, should be considered as a preoperative adjunct or palliative treatment to prevent recurrent hemorrhage (class IIb, level of evidence C). For those with neurologic symptoms or hemorrhage referable to a dural arteriovenous fistula, endovascular treatment alone might be curative or might be used in combination with other therapies, such as surgery or radiosurgery, as palliative treatment to prevent stroke or hemorrhage (class IIb, level of evidence C).

The American Heart Association reports that it receives funding primarily from individuals, foundations, and corporations (including pharmaceutical and device manufacturers and other companies) that make donations and fund specific programs and events. "The association has strict policies to prevent these relationships from influencing the scientific content," the association notes in a press statement. Revenues from pharmaceutical and device companies are disclosed at www.americanheart.org/corporatefunding . Meyers has disclosed no relevant financial relationships. Disclosures for other members of the writing group are listed in the paper.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.