A rare and deadly heart inflammation has been reported in three Ohio horses. Two of the three died and the third was released yesterday in improved but guarded condition from the Ohio State University Medical Center. The condition, known as pericarditis, is an inflammation in the sac that surrounds the heart. It results in a buildup of fluid and constriction of the heart muscle. Veterinarians in Ohio and Kentucky suspect it may result from the same environmental toxins that have caused more than 1,000 foals to be born dead or near death in the two states since March. At least two of the three Ohio cases came from farms that experienced multiple foal deaths this spring.