The recent discovery of an abnormal structure inside the left atrial chamber of the heart may lead to blood clots, according to a study published in the Journal of the American College of Cardiology: Cardiovascular Interventions.

A team of researchers at the University of California Irvine, led by cardiologists Subramaniam Krishnan and Miguel Salazar found the pouch-like form during an autopsy procedure. Following the discovery, the physicians collected data on ultrasound and computed tomography (CT) scans, and found that out of more than 700,000 cases of stroke, 30 percent to 35 percent of the victims have this deformity.

With nearly one-third of blood clot origins unknown in those who have suffered strokes, the team hopes that this discovery may help neurologists prevent future strokes in patients. More studies in the future will be needed in order to determine how much this structure may affect patients who have survived strokes.

“It was thought that the body of the left atrium was largely smooth and unlikely to be a source of blood clots, but we have found that not to be true for roughly one in three people,” said Krishnan.

According to the American Heart Association, the rate of stroke-related deaths declined by nearly 34 percent from 1995 to 2005.