Brazilian former Formula One driver Nelson Piquet was admitted earlier this week to a Sao Paulo hospital, where, according to unconfirmed press reports, he underwent successful surgery to unblock a clogged artery.

The 61-year-old, a three-time winner of the F1 Drivers' Championship in the 1980s, has not yet been discharged but is out of danger, spokespersons at the Albert Einstein Hospital told Efe.

Those same spokespersons refused to divulge why Piquet was hospitalized and whether he was operated on, saying they were respecting the wishes of the patient's family.

The 1981, 1983 and 1987 F1 champ, according to press reports that do not cite a source, underwent a procedure Tuesday to unblock an artery after medical exams two years ago revealed a heart malformation.

Piquet, who won 23 F1 races and had 60 podium finishes over 13 seasons, also competed in the Indianapolis 500 in 1993. EFE