Former President Bill Clinton underwent a successful heart procedure on Thursday to open a blocked artery in his heart with two stents after he had experienced chest discomfort, his spokesman said.

Clinton, 63, had quadruple heart bypass surgery in 2004 to free up four blocked arteries and the latest incident comes after he has traveled twice to Haiti to help recovery efforts after a devastating earthquake there.

Today, President Bill Clinton was admitted to the Columbia Campus of New York Presbyterian Hospital after feeling discomfort in his chest, Douglas Band, counselor to Clinton, said in a statement.

Following a visit to his cardiologist, he underwent a procedure to place two stents in one of his coronary arteries. President Clinton is in good spirits, and will continue to focus on the work of his foundation and Haiti's relief and long-term recovery efforts, Band said.

Having stents placed in heart arteries is a relatively quick and routine procedure among patients like Clinton who have suffered from heart disease.

Stents are tiny mesh tubes used to prop open heart arteries that have been cleared of blockages via angioplasty. They are now often coated with drugs to help prevent reclogging.

Clinton's chest pains were possibly caused by failing grafts from the quadruple bypass heart surgery he had six years ago, a cardiologist said on Thursday.

If he had four grafts it is not surprising that one of them would start to fail by now, said Dr. Cam Patterson of the University of North Carolina, adding they last on average about 10 years.

Clinton was president from 1993 until 2001 and like many Americans he has struggled with his weight.

He presided over eight years of economic prosperity and political tumult during a presidency tarnished by a sex-and-perjury scandal that led to his impeachment and a bitter fight to stay in office.

While in office he was known for his love of burgers and junk food and was also seen regularly jogging.

Following his 2004 heart operation he has looked trim and fitter than while he was president -- something he attributed to the South Beach diet, which excludes processed foods and favors lean meat.

He established a foundation to build his legacy beyond the White House which has pushed big corporations and rich people to actively try to fix some of the world's worst problems.

Most recently Clinton, as U.N. special envoy to Haiti, has coordinated relief efforts after the January 12 Haiti earthquake. His wife, Hillary Clinton, is the current secretary of state under President Barack Obama.

A senior administration official said Hillary Clinton had left Washington for New York. The official declined to say if there would be any changes to Clinton's planned trip to Qatar and Saudi Arabia, which was due to start on Friday.

Just before his 2004 surgery, Clinton spoke on CNN's Larry King Live, about his heart blockage: Some of this is genetic and I may have done some damage in those years when I was too careless about what I ate ... I've got a problem and I've got a chance to deal with it, Clinton said.

Clinton, a former governor of Arkansas, presided over the nation's longest economic boom but had many policy setbacks, most notably on his plans for healthcare overhaul which he tried to tackle when he took office in 1993.

He remains popular despite the sex-and-perjury scandal involving his affair with White House intern Monica Lewinsky that indelibly marked his presidency.

(Reporting by New York bureau, Bill Berkrot, Maggie Fox, writing by Mark Egan, editing by Jackie Frank)