Christina Louca has plenty of heart. Sophomore year, life took an unexpected turn for the Seaford cheerleader and runner when she was shockingly diagnosed with Wolff-Parkinson-White Syndrome, a cardiac condition that, at its worst, could cause the 16-year-old to have a heart attack. “I never really dealt with something like this; I never had health problems in the past,” Louca told The Post. “I was really shocked, and I was pretty nervous,” she added of the February diagnosis. Christina Louca practices her routine. Corey Sipkin for the NY POST Such a frightening condition was completely out of sight and out of mind for Louca and her family, as nothing had appeared in a routine physical to indicate its presence. Louca’s case was flagged by an EKG only because the Seaford school district off