The Uncoordinated U.S. Primary Stroke Centers

From the International Stroke Conference in San Antonio

The good news for U.S. stroke patients is that in March 2010, 685 certified primary stroke centers existed in America. The bad news is that no one makes sure they’re optimally placed to maximize coverage of the U.S. population.

The Joint Commission, a U.S. hospital accreditation organization, began certifying primary stroke centers in December 2003. The idea was that these centers would specialize in state-of-the-art stroke care and become the prime locations for acute stroke patients to receive care.

The concept has certainly taken root. According to Dr. Karen C. Albright, a neurologist at the University of California, San Diego, 524 certified American primary stroke centers existed by November 2008, and another 102 came on board during the following year, through late September, 2009. The pace for new center certifications has held steady, with another 59 centers added to the list during a little more than another 5 months.

Stroke patients who live in the white areas have a greater than 60 minute trip to their nearest primary stroke center (photo by Mitchel Zoler).

But according to Dr. Albright, many of the new centers added during Nov. 2008-Sept. 2009 were “in proximity to existing centers.” No person or group controls where new stroke centers open, and they’ve left big gaps of uncovered population. Based on the centers that existed last September, Dr. Albright estimated that roughly 63 million to 135 million Americans lived more than 60 minutes away from the closest primary stroke center (see map). The upper end number, 135 million, applied if all emergency stroke transport was by ambulance. The number fell to 63 million if all centers had helicopter transport available, but that’s a big if because in reality many centers don’t use air transport.

Some excellent models exist for better emergency-care coordination, most notably the way trauma care is integrated and delivered across the U.S., particularly by regional systems like the Southeast Texas Trauma Regional Advisory Council.  Recently, SETTRAC set up regional coordination of emergency stroke care in the Houston area.

Now all that has to happen is for this approach to spread through the rest of Texas, and then the rest of the United States.

—Mitchel Zoler (on Twitter @mitchelzoler)

Imaging Resets the Stroke Clock

from the International Stroke Conference in San Antonio

Until recently, acute stoke treatment ran strictly by the clock. Now that’s changing.

image courtesy Flickr user teh kankaik

First line treatment, intravenous infusion of a clot-disolving drug like tissue plasminogen activator (tPA), initially had a 3 hour time window, recently pushed back to 4.5 hours. More aggressive, endovascular treatments aimed at removing blood-blocking clots–intra-arterial tPA, the Merci clot retriever, and the Penumbra clot suction device–have received time limits of 6 hours (for intra-arterial tPA) or 8 hours (for the mechanical devices).

But interventional neurologists at several U.S. stroke centers now use these treatments beyond the 8 hour limit on selected patients, those with enough salvageable brain when assessed by perfusion CT or by diffusion-weighted MRI.

This approach received a boost at the Stroke meeting last week, when a review of 237 patients selected this way showed that encovascular reperfusion treatments were safe and effective for many patients who started on treatment anywhere from 8-111 hours after their stroke began.

“A lot of patients are deprived treatment based on time,” said Harvard neurologist Raul G. Nogueira, who reported the results. “It’s time to get away from the time window. No question that sooner is better, but some patients benefit later.”

Dr. Nogueria acknowledged the next step is to prove this in the prospective study now being assembled. In the meantime, his findings give some validation to a practice that’s become routine at many U.S. stroke centers.

—Mitchel Zoler (on Twitter @mitchelzoler)

Age Effect Missed in Many CREST Carotid-Treatment News Reports

from the International Stroke Conference in San Antonio 

The headline message from the CREST study reported at the stroke meeting last Friday was that two different revascularization procedures for severe carotid artery stenosis–carotid stenting and carotid endarterectomy–were equally safe and effective.  This oversimplification was true only if all of the patients undergoing these treatments were 70 years old. 

The reality was that while, on average, the two procedures had very similar results, the study also showed a powerful age effect that led to substantially different outcomes depending on patient’s age. 

Here is the graphic presented on Friday that showed this relationship: 

photo by Mitchel Zoler

The dark solid line follows the changing relationship between patient age and the relative benefit (less than 1.0) or relative harm (more than 1.0) from carotid artery stenting (CAS) compared with carotid endarterectomy (CEA). 

Patients younger than 70 who underwent stenting had fewer adverse events–the combined rate of death, stroke, or myocardial infarction–than patients who underwent carotid endarterectomy. At age 60, the relative rate of adverse events with carotid stenting was roughly 35% below that of 60-year old patients who underwent endarterectomy. At age 50, the relative rate of adverse events was cut by more than half by stenting. 

The situation flipped for patients older than 70. At age 80, patients treated by stenting had a greater than 50% higher rate of adverse events than those treated with endarterectomy. 

News reports that simply said the two treatments had similar outcomes missed this key CREST finding. 

My full report on the CREST results is here.

—Mitchel Zoler (on Twitter @mitchelzoler) 

Is There Anything Exercise Can’t Help?

From the International Stroke Conference in San Antonio

Image courtesy of Flickr user Josiah MacKenzie (CC)

If you hate to get off the sofa, here’s some more news about exercise that you probably don’t want to hear.

Transient ischemic attack (TIA) is often considered a warning. By some estimates, more than half of those with a TIA will have a stoke within the next 5 years.  TIA shares a number of risk factors with cardiac disease, among them hypertension, smoking, diabetes, and cholesterol.  What’s bad for the heart must be bad for the brain too, right?

Right.  And now there is increasing evidence that what’s good for the heart must be good for the brain too.

A small study presented at the meeting showed that patients with a TIA benefit from the same type of exercise rehabilitation program that cardiac patients go through following an MI.  Fourteen post-TIA patients participated in a 6-week rehabilitation program.  Patients attended three 1.5-hour sessions per week.  Sessions included a warm-up, timed aerobic exercise, resistence training, and a cool-down.  Intensity progressed with patient tolerance.

The researchers measured changes in blood pressure, gait speed, and endurance.  At the end of 6 weeks, systolic blood pressure was decreased by 8.71 mm Hg and diastolic blood pressure was decreased by 7.18 mm.  While the results were not statistically significant, study author Marieke Van Puymbroeck of Indiana University noted these decreases in blood pressure were clinically meaningful. Previous work has shown that a 5 mm Hg decrease in systolic translates to a 14% decrease in stroke risk, while a 5 mm Hg decrease in diastolic blood pressure translates to an impressive 42% decrease.

While the findings need to be validated in a larger study that controls for changes in medication, it looks like there’s another reason to lace up those trainers.

— Kerri Wachter (on Twitter @knwachter)

Regional Centers for Cardiac Arrest: Will Anyone Listen?

Today, an expert panel put together by the American Heart Association released detailed recommendations for establishment of a network of regional centers to provide acute care to patients who experience out-of-hospital cardiac arrest (OOHCA). 

courtesy Flickr user sztyui

The report documents what a killer OOHCA can be, slaying 300,000 Americans annually, but it also notes a striking, fivefold disparity in mortality rates that now exists across the country. The reason: a few select locations have integrated, regional care systems in place that get patients to expert centers quickly so that state-of-the art treatment is applied. But right now, most of the U.S. lacks these centers and a system to bring patients to them. 

My news story on the report is here, and the expert policy statement is here. 

The report makes clear that the answer is to open specialized, regional centers around the country, tied to emergency medical services to bring patients in. These networks are modeled on the existing trauma centers and stroke centers that are in place throughout the U.S. 

It’s a wonderful concept. But the troubling question I had as I read the report was: Which people or groups would take this on as their mission, to ensure these regional centers come into being soon? 

The expert panel’s chair, Dr. Graham Nichol of the University of Washington in Seattle, told me that people committed to this cause, be they physicians, administrators, nurses, medics, or  others, will need to self-select themselves to take on this effort in each region or community. He added that the effort will have the support of the three groups that sponsored the report, the American Heart Association, the American College of Emergency Physicians, and the National Association of State EMS Officials, but mostly, Dr. Nichol said, the onus will be on individuals to act as local champions for this cause. 

I hope it works, but it sounds to me like a tall order and a leap of faith to think that organized OOHCA care centers will sprout up in the next few years like so many flowers blooming. 

But one fact in the report gives me reason to think that Dr. Nichol’s scheme will work. The report noted that as of April 2009, more than 500 certified stroke centers were in operation around the U.S. I wrote about stroke centers in their early days, about 5 years ago, and at that time, the end of 2004, about 60 stroke centers existed, and they came into being just about the same way that Dr. Nichol and his panel envisions for cardiac arrest centers.  Here’s hoping this history repeats itself. 

—Mitchel Zoler (on Twitter @mitchelzoler)

Too Good to Be True?

From the annual congress of the European Society of Cardiology in Barcelona.

How do you react to smashing success in a drug trial?

That was the dilemma, and seemingly the only problem facing the results from a study with the new antithrombic drug dabigatran, which rang up stunning numbers against its entrenched comparator, warfarin, for preventing stroke or systemic embolism in patients with atrial fibrillation.

Dr. Stuart J. Connolly/photo Mitchel Zoler

Dr. Stuart J. Connolly from McMaster University in Hamilton, Canada, reported the remarkable results of the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) here on Aug. 30. The two dosages of dabigatran tested either significantly cut the event rate with safety equal to warfarin, or had comparable efficacy with significantly better safety in a study with 18,000 patients (full results were simultaneously published in the New England Journal of Medicine). This double win for dabigatran came for a drug that’s also far easier to use than warfarin.

The immediate reaction by cardiologists on the scene was generally unmitigated euphoria. “A paradigm change” said one, a “revolution” said another, a “breakthough” said a third, a “real winner” said a fourth. 

At a time of intensified skepticism, when the watchword is that what’s too good to be true probably is, what’s to be made of a result that’s too good but may well be just that?

–Mitchel Zoler at 10:45 AM, Aug 31, in Barcelona (on twitter @mitchelzoler)

The Beginning of the End for Warfarin?

From the annual scientific session of the American College of Cardiology, Orlando

Warfarin, the reigning standard therapy for stroke prevention in atrial fibrillation, has long been viewed by the pharmaceutical industry as a big fat sitting duck: it’s a widely prescribed, cheap drug that’s just begging for replacement by one of a host of easier to use and perhaps safer antithrombotic agents in the developmental pipeline.

But warfarin may finally be dethroned not by a better antithrombotic, but by a little plug made of nitinol wire and fabric called the Watchman. It’s a percutaneously implanted permanent device designed to seal off the left atrial appendage, the source of most atrial thrombus.

Here at the ACC meeting Dr. David Holmes of the Mayo Clinic presented the results of the Phase-3 PROTECT AF trial, in which during 900 patient-years of followup the Watchman resulted in a 91% reduction in hemorrhagic strokes and a 32% decrease in the combined endpoint of any stroke or all-cause mortality compared to warfarin.

Atritech, the Watchman’s developer, has a marketing approval hearing before an FDA advisory panel in late April.

—Bruce Jancin

Photo of Dr. David Holmes (above) taken by Bruce Jancin.