Los Angeles Chargers head coach Jim Harbaugh said on Monday that he will wear a heart monitor for the next two weeks after leaving his team’s game on Sunday with an “atrial flutter.”

Harbaugh left the sideline during the first quarter of the Chargers’ 23-16 win against the Denver Broncos, with the team later announcing he was questionable to return with illness.

The 60-year-old did return to the game by the end of the quarter and coached the rest of the game on the sidelines.

Afterwards, Harbaugh said he left the game with an arrhythmia, also known as an irregular heartbeat. He added that he has dealt with similar episodes in the past, remembering one in 1999 and another in 2012.

“I’ll always remember the one in 2012, it was during the Monday night game,” Harbaugh told reporters on Sunday. “(Former San Francisco QB) Colin Kaepernick and the 49ers vs. the Chicago Bears, and Colin had a great night that night.

“After the game, got checked out. Ended up having to have an ablation for that one because it didn’t go back into rhythm, but 2-0 with arrhythmias.”

He also said that having another ablation procedure to help the issue is not off the cards. A cardiac ablation is a treatment for irregular heartbeats which “uses heat or cold energy to create tiny scars in the heart” to “block faulty heart signals and restore a typical heartbeat” using catheters inserted through a blood vessel, according to the Mayo Clinic.

Harbaugh also recalled telling Chargers quarterback Justin Herbert ahead of Sunday’s game that he felt unusually pumped up.

“I don’t know if I’m really fired up for the game or this is my arrhythmia kicking back in,” Harbaugh recalled telling Herbert. “Could be one or the other. Wasn’t sure.”

Speaking to the media on Monday, Harbaugh explained that he will wear the heart monitor for the next fortnight after consultation with cardiologists before being reevaluated. He does not expect to miss any time from the team.

“They know how deeply committed I am,” Harbaugh said. “It would take my heart stopping for me not to be out there on the sideline.”

The Chargers travel to face the Arizona Cardinals in Week 7 on Monday before hosting the New Orleans Saints on October 27.