Saints defensive tackle Nick Fairley has been absent from Organized Team Activities this week, and according to Jennifer Hale‏ of Fox Sports, it's because Fairley recently underwent tests that show heart trouble that could jeopardize his career.

That's scary news for Fairley and bad news for a Saints defense that ranked 27th in total defense in 2016. The former first-round pick of the Detroit Lions (13th overall) in 2011 is coming off his best season as a pro. Fairley started all 16 games for the Saints last season and racked up a career-best 6.5 sacks and 29 tackles. The Saints rewarded Fairley this offseason with a four-year, $28 million contract.

Saints players who speak to Fairley regularly haven't been able to get in touch with him, according to NFL Network's Mike Garafolo.

Fairley joined the Saints last season after a season with the St. Louis Rams following four seasons in Detroit.