U.S. Vice President Dick Cheney, 66, was treated for an irregular heartbeat discovered during a doctor’s visit on Monday, his office said.

Cheney wanted to see the doctor “for a lingering cough from a cold.” Instead, he was found to have "atrial fibrillation, an abnormal rhythm involving the upper chambers of the heart," Megan Mitchell, the representative for the George Washington University Hospital, said, according to Reuters.

Doctors at GWUH gave Cheney an electrical shock to restore the heart’s normal rhythm.

Cheney returned home after the procedure and will be back at the White House on Tuesday, his office said.

Cheney, who has a history of heart problems, survived four heart attacks before he became vice president. The last one dated immediately after the November 2000 election was listed as mild.

Cheney had quadruple bypass surgery and operations to clear blocked arteries in 1988. He had been also fitted with a pacemaker in 2001. Its battery, which had been running slow, was replaced during a minor surgery in July.

He had surgery to treat abnormal blood vessels, or aneurysm, behind both knees in September 2005.

Atrial fibrillation is a condition experienced by 2.8 million Americans. The disease is affecting more individuals as the population age increases. Left untreated, the patient may suffer blood clotting in the brain, leading to a stroke.