Sen. Mark S. Kirk, R-Ill., underwent surgery Monday to remove his gallbladder after doctors discovered gallstones that had been creating stomach pains, the senator’s office announced.

Kirk, who suffered an ischemic stroke in January 2012, is expected to make a swift recovery.

“Saturday morning Senator Mark Kirk went to Northwestern Lake Forest Hospital with stomach pains. Doctors determined that, due to the fact that he had gallstones, his gallbladder needed to be removed,” a statement from Kirk’s office read. “This morning Senator Kirk underwent a successful surgery to have his gallbladder removed and is resting comfortably. His doctor expects a quick recovery.”