Healthcare

Connections: Stroke and TIA—important new guidelines | Spring 2018

Connections is a quarterly newsletter for primary care providers covering the latest developments and advances in medicine at OHSU. Learn about the many clinical, education and outreach resources available to you and your patients.

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From the OHSU Stroke Center

Hormozd Bozorgchami M.D. headshot

Hormozd Bozorgchami, M.D.

Dr. Bozorgchami is assistant professor of neurology at OHSU. He specializes in managing acute strokes and has advanced training in interventional neuroradiology and vascular neurology. He is board certified in neurology and vascular neurology.

New guidelines for treating ischemic stroke

In January 2018, the American Stroke Association/American Heart Association jointly released new guidelines for treating ischemic stroke. This update, based on expert review of more than 400 published studies, contains important changes to the 2013 guidelines.

New 2018 ischemic stroke guidelines

Research, including much conducted at OHSU, shows that mechanical thrombectomy limits the risk of disability after a stroke. Now more patients are eligible for this procedure after large-vessel occlusion strokes, as the time to treatment has expanded up to fourfold.

Changes in time window for mechanical thrombectomy

2013 Guidelines 2018 Guidelines
Thrombectomy can be done up to 6 hours after patient was "last seen well" Thrombectomy can be done up to 24 hours if advanced imaging criteria are met

Reducing mortality and dependence on caregivers

With more patients now eligible for clot removal, death and disability from stroke are likely to decrease. One in every two to three patients who would previously have died or experienced major disability is now likely to be capable of self-care and perhaps much more.

Expanding device indications, changing stroke protocols

The indication for one currently approved thrombectomy device has been expanded to reflect the 2018 guidelines. Stroke centers now receive patients who have had symptoms much longer than under the old guidelines — up to 24 hours, depending on imaging, instead of up to eight or 10 hours.

Long-term monitoring for atrial cardiomyopathy

Cardiac monitoring in the hospital or with a two-day home monitor has been part of stroke prevention for some time. However, these brief periods are not sufficient to reveal paroxysmal atrial fibrillation, as longer-term monitoring can show. As part of our workup, the OHSU stroke team now recommends between two to four weeks of monitoring for selected patients. We use the Zio Patch, which can be placed at bedside or in clinic. Additionally, some patients may be candidates for the Reveal Linq insertable cardiac monitoring system, which can be implanted in a simple bedside procedure.

Longer-term cardiac monitoring raises new research questions. As the longer monitoring periods identify more atrial fibrillation, providers and researchers want to determine whether the degree of atrial fibrillation burden determines the most optimal form of stroke prevention treatment. The 30 percent of strokes deemed "cryptogenic" will likely shrink as we learn how many are caused by atrial cardiopathy.

Practice pearls in stroke prevention

Patient- and provider-friendly heart monitoring

The Zio patch offers 14-day heart monitoring through a simple adhesive device placed on the chest. The provider's office mails it to the device maker when monitoring is complete and receives a report reviewed and signed by a cardiologist. This type of monitoring can be especially helpful for patients in rural settings.

Patient education and lifestyle tracking

Hypertension remains the most undertreated risk factor for stroke. Simply teaching patients to maintain home blood pressure diaries such as those offered through the American Heart Association website can help manage this risk. A modestly priced blood pressure machine and diary can greatly reduce the risk of stroke recurrence.

When is a stroke not a stroke?

Is a transient ischemic attack truly a "mini-stroke" if the patient recovers, even if imaging shows evidence of a stroke? Identifying what is – and is not – a TIA remains a topic of debate in neurology. Episodes of hypoglycemia, orthostatic hypotension, seizures and complex migraine may masquerade or be misdiagnosed as TIAs. Most referrals to our practice are diagnostic, e.g., a patient has had 20 TIAs and we are seeking the cause.

Researchers continue to investigate ways of preventing stroke after TIA, and new medications are on the horizon in clinical trials, but there are no definitive answers yet. Importantly, guidelines now recommend urgent treatment — within 1 week — for patients who have small strokes or TIAs due to carotid stenosis.

Referral indications

You may wish to consult by phone or refer a patient for evaluation if:

  • The standard stroke workup is negative and the patient has no major risk factors for stroke.
  • A young stroke patient (under 55) has a negative workup for stroke risk factors. These patients may need longer-term monitoring and additional testing.
  • A patient needs stroke intervention.
  • You are interested in a second opinion on "borderline" imaging findings.
  • There are major management questions.

Stroke resources

Effective stroke treatment demands multidisciplinary care. As Oregon's only academic health center and first Joint Commission-certified comprehensive stroke center, OHSU has a strong tradition of stroke research and innovation. Our leaders have enrolled many patients in stroke trials, including those instrumental to the development of today's mechanical thrombectomy technology. We still offer patients and providers the chance to participate in clinical research here or through national or international trials.

Contact us

OHSU Stroke Center specialists are always available to consult with you. If you have questions or would like to refer a patient for evaluation, please call the OHSU Physician Advice and Referral Service at 503-494-4567.