NFL

Vikings DE Everson Griffen was tested for heart-related issues

<p>Sep 14, 2014; Minneapolis, MN, USA; Minnesota Vikings defensive end Everson Griffen (97) against the New England Patriots at TCF Bank Stadium. The Patriots defeated the Vikings 30-7. Mandatory Credit: Brace Hemmelgarn-USA TODAY Sports ,Sep 14, 2014; Minneapolis, MN, USA; Minnesota Vikings defensive end Everson Griffen (97) against the New England Patriots at TCF Bank Stadium. The Patriots defeated the Vikings 30-7. Mandatory Credit: Brace Hemmelgarn-USA TODAY Sports</p>

Sep 14, 2014; Minneapolis, MN, USA; Minnesota Vikings defensive end Everson Griffen (97) against the New England Patriots at TCF Bank Stadium. The Patriots defeated the Vikings 30-7. Mandatory Credit: Brace Hemmelgarn-USA TODAY Sports ,Sep 14, 2014; Minneapolis, MN, USA; Minnesota Vikings defensive end Everson Griffen (97) against the New England Patriots at TCF Bank Stadium. The Patriots defeated the Vikings 30-7. Mandatory Credit: Brace Hemmelgarn-USA TODAY Sports

Vikings DE Everson Griffen leads the team with three sacks this season. Brace Hemmelgarn USA TODAY Sports

Defensive end Everson Griffen was a surprise scratch for the Minnesota Vikings' Week 6 win over the Kansas City Chiefs. He wasn't listed on the team's final injury report, but an undisclosed injury kept him out of the action on Sunday.

As part of an NFL investigation into his unexpected absence, Griffen underwent a "precautionary," heart-related test to make sure he's healthy enough to return this week, according to ESPN's Ben Goessling.

More from FoxSports

Griffen does not have an irregular heartbeat nor does he have a history of heart problems, a source told ESPN. Although he missed Wednesday's practice while undergoing the league's tests, the defensive end should be back at practice on Thursday.

Vikings head coach Mike Zimmer didn't know this was going to be an issue this week.

"I don't know anything about the NFL investigating," Zimmer said on Monday, per ESPN. "All I know is the guy was sick because I saw him."

The Vikings will be happy to have Griffen, the team's leading sacker (3.0 in 2015), back in the lineup for this Sunday's showdown with the Detroit Lions.

MORE NEWS: Want stories delivered to you? Sign up for our NFL newsletters.