Stroke Risk Not Improved After Surgery

Blockage operation may not reduce stroke risk after a mini-stroke

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Following a mini-stroke patients are at a heightened risk for a stroke.  Many take precautions to make sure that doesn't happen. However, some methods for stroke prevention are not proving to be effective protection.

Surgery to increase blood flow following a mini-stroke does not appear to lower stroke risk over a two-year period as compared to traditional medical therapy.

"Talk to your neurologist about stroke prevention."

Dr. William J. Powers of the University of North Carolina School of Medicine at Chapel Hill found that the benefits of improved medical therapy effectively outweighed those of an operation for atherosclerotic internal carotid artery occlusion (AICAO), a condition causing about 10 percent of ischemic strokes.

Patients with this condition experience a thickening and blockage of the internal carotid artery, which supplies blood to the brain.

During the Carotid Occlusion Surgery Study researchers enrolled 195 patients with AICAO and insufficient blood flow to the brain, which was identified with a PET scan. Of those, 97 were randomly chosen to receive surgery while the remainder did not.

The trial was conducted at 18 centers in the U.S. and Canada between 2002 and 2010. All participants were recommended to receive medications to treat blood clots and intervention for risk factors. Patients were followed for two years.

In both groups investigators measured the outcome by examining stroke and death rates either 30 days from surgery or randomization, and ipsilateral stroke within two years.

The study was ended early since the results suggested the surgery was not effective in preventing stroke.  At the end of two years, 21 percent of the surgery group had experienced a stroke or died versus 22.7 percent of the group that did not receive surgery. At 30 days, 14.4 percent of the surgery group had a stroke as compared to 12.4 percent in the nonsurgical group.

The research was recently published in the Journal of the American Medical Association.

Reviewed by: 
Review Date: 
November 10, 2011
Last Updated:
November 12, 2011