Stroke: Good Outcomes in Extend-IA

Interventional neurology is having a good run at the American Heart Association/American Stroke Association’s International Stroke Conference in Nashville, Tenn. In addition to the favorable results of the trial known as ESCAPE, in which adding clot removal (endovascular thrombectomy) to clot dissolving therapy showed dramatic outcomes, a related study called EXTEND-IA also showed benefits for stroke patients.

Bruce Campbell, MBBS, Ph.D., Consultant Neurologist and Head of Hyperacute Stroke, Department of Neurology, Royal Melbourne Hospital, Parkville, Australia and colleagues reported on a trial to see whether more advanced imaging, better devices to remove clots, and earlier intervention improved outcomes. The device use in the trial was the Solitaire Flow Restoration stent retriever.

The 70 patients, all of whom had ischemic strokes, got tPA within 4.5 hours of the onset of the stroke. The targets were occlusions of the internal carotid or middle cerebral arteries, and the patients had to have salvageable tissue with an ischemic core less that 70 ml.

They were randomized to either tPA plus clot retrieval therapy or simply tPA.

The researchers then measured the proportion of the lesion that had been reperfused at 24 hours, and the proportion of patients with early neurological improvement. The secondary outcome was measurement on the modified Rankin Scale.

The patients who got both tPA and the intervention did so well that the trial was stopped early by the institution’s data safety and monitoring committee on the grounds of efficacy.

"The important thing is to get on straight away and remove the blockage,Campbell said in a briefing this morning.

That interim review was prompted by the release of the results of the MR CLEAN trial, which last year showed essentially the same thing.

The patients in EXTEND-IA who got both therapies showed 100% reperfusion of the ischemic area vs. 37% reperfusion seen in those who got only tPA.

In concluding, the researchers said that patients who got both treatments showed “improved reperfusions, earlier neurological recover, and better functional

outcomes.”

Reporting on SWIFT PRIME, a Los Angeles-based study that was halted just a week ago, Jeffrey Saver, MD, of the University of California at Los Angeles Comprehensive Stroke Center. The trial's acronym stands for Solitaire FR as Primary Treatment for Acute Ischemic Stroke. Saver is also focused on bringing pre-hospital care into the equation, and in finding ways to train ambulance paramedics to identify patients who can be helped by the therapy.

Ultimately, that could include using portable CT scanners on ambulances--an experiment underway in Berlin, Germany and in some stroke centers in the US.

Saver said his SWIFT PRIME trial had originally expected to enroll more than 800 patients at 69 sites, but at the time it was halted because of efficacy it had enrolled about 191 patients. Those who got the intervention of mechanical clot removal had an 88% reperfusion rate, with the result that blood flow to 50% or more of the brain territory that had been obstructed by the stroke was restored.

The concensus of the three physicians was that their research was a major game-changer in stroke treatment for a set of patients whose strokes would otherwise have been life-altering.

The next challenge is integrating the findings into care--a huge challenge involving setting up new comprehensive stroke centers, (the US needs 300 and has about 70 they said,), training medical teams including prehospital and emergency specialists, and figuring out how to get the care to patients who do not live near a stroke center.

"A lot of teaching has to happen," said Michael Hill, MD, the lead investigator in the ESCAPE trial.