ALLENDALE, Mich. (AP) The Grand Valley State basketball player who collapsed and died after a pickup game suffered from a rare heart defect, an autopsy shows.

Derek Smith's defect, in a major artery that supplies blood to the heart, had never been diagnosed, said Dr. David Start, who performed the autopsy Monday.

Instead of a round opening, the opening in Smith's artery was narrow and slit-shaped, restricting blood flow to the 19-year-old freshman's heart, Start told The Grand Rapids Press.

The defect occurs in 1 to 2 percent of the population, and sedentary people could have the condition their whole lives without knowing it, said David Wohns, a cardiologist at Spectrum Health Butterworth.

"Sometimes there can be a passing-out spell, if you're lucky, or sudden death, if you're not," Wohns said.

Smith, a 2001 graduate of Grand Rapids Union High School, collapsed shortly after 9 p.m. Sunday at the school's gymnasium, athletic director Tim Selgo said. Smith fell backward while sitting on the gym floor, taking a break after playing a pickup basketball game.

Smith was a redshirt freshman on the men's basketball team. The pickup games on Sunday were not affiliated with the team.

"We're still in a complete state of shock," Grand Valley coach Terry Smith said. "Derek was the nicest kid in the world. One minute he was playing basketball and joking with his buddies. The next minute he was gone."

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