(Reuters Health) – Long-term follow-up of patients in a 2014 study confirms that acute ischemic stroke patients recover better with endovascular treatment than with thrombolytic therapy. The conclusion is based on 500 Dutch patients treated in a landmark study known as MR CLEAN. The findings, released online April 5th in the New England Journal of Medicine, may encourage more hospitals to adopt the technique.

In earlier results from the study, one third of patients whose treatment included using a device to extract a clot from a brain artery achieved functional independence by the 90-day mark after their strokes compared to 19 percent given usual care.

Now, two years of data show functional independence for 37 percent of patients with clot removal versus 24 percent with clot-busting drugs alone.

“We are delighted. It is icing on the cake,” said Dr. Reza Jahan of the University of California at Los Angeles Stroke Center, who was not connected with the study. “It confirms the long-term durability” of the technique and it will encourage more centers to use it, he said.

The MR CLEAN study, combined with subsequent positive results released soon afterward, “has made a huge difference” in how doctors treat strokes said study coauthor Yvo Roos, a neurologist at the Academic Medical Center in Amsterdam. “This is now standard care,” he told Reuters Health in a telephone interview.

Dr. Jahan said the new study results reinforce efforts to evaluate stroke patients before they even reach a hospital and then immediately get them to a comprehensive stroke center if they are candidates for clot removal. “It will get these patients to the treatment they need faster, rather than the current model, where they may go to a primary stroke center to get clot-busting drugs and valuable time is lost trying to transport them to a comprehensive stroke center,” he said by phone.

The findings apply to patients with acute ischemic stroke, which is the most common type of stroke and affects up to 125,000 patients in the U.S. and 90,000 in Europe each year.

Typically, thrombolytic drugs only open the blocked artery in about a third of the cases, which is why doctors have hoped that removing the clot directly would produce better recovery. Clot removal is expensive at $57,031 for the extraction and the first 90 days of other stroke treatment, according an analysis published in December in the journal Stroke. Treatment without clot extraction costs $44,752.