Georgia's junior senator remains in an Atlanta hospital where he's being treated for an irregular heartbeat and a blood clot in his leg.
A spokeswoman for Isakson said Wednesday the 65-year-old Republican was doing well under doctors' supervision at Piedmont Hospital.
He was admitted on Monday night after doctors detected an irregular heartbeat and a blood clot in his right calf during a routine checkup to monitor his recovery from a bacterial infection the week before.
Isakson spokeswoman Joan Kirchner said the senator's latest health setback would not impact his re-election plans.
He is seeking a second term in the Senate.