He underwent a procedure and it looks like he is going to be fine.
“Today President Bill Clinton was admitted to the Columbia Campus of New York Presbyterian Hospital after feeling discomfort in his chest. 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. In 2004, President Clinton underwent a successful quadruple bypass operation to free four blocked arteries.”
Of course the Huffington Post won’t have to shut down comments like they did when Dick Cheney underwent a similar procedure.