DETROIT – Former U.S. Rep. John Dingell, the longest-serving member of Congress in U.S. history, has been released from the hospital after having a pacemaker installed to regulate his heart.

The office of Dingell’s wife, U.S. Rep. Debbie Dingell, says the 89-year-old man left the hospital on Sunday after the procedure was performed last week.

A post from Debbie Dingell on her Facebook page says there is “work ahead but he remains at my side for wisdom and strength.”

A pacemaker can help control abnormal heart rhythms.

John Dingell, a Democrat, served 59 years in Congress. His wife was elected to his Detroit-area seat last year after he didn’t seek re-election.