WASHINGTON (AP) — Supreme Court Justice Ruth Bader Ginsburg had a heart stent implanted on Wednesday, reviving talk about how long the 81-year-old liberal jurist will be staying on the court.

Ginsburg was expected back at work on Monday, but her hospitalization — just three weeks after elections handed Republicans control of the Senate — raised anew the question whether President Barack Obama would be able to appoint a like-minded replacement.

Ginsburg's procedure came after a blockage was discovered in her right coronary artery, said court spokeswoman Kathy Arberg. The justice was taken to the hospital by ambulance Tuesday morning after she "experienced discomfort" during routine exercise at the court with her personal trainer, Arberg said. The justice was expected to leave the hospital within 48 hours.

Ginsburg, who leads the court's liberal wing, has for years been fending off questions about whether she should retire and give a Democratic president a chance to name her successor. She underwent operations for colorectal cancer in 1999 and for pancreatic cancer in 2009, was hospitalized after a bad reaction to medicine in 2009 and suffered broken ribs in a fall two years ago.

But the court's oldest justice has not missed any time on the job since President Bill Clinton appointed her in 1993.

For several years, liberal academics have been calling on Ginsburg and, to a lesser extent, 76-year-old justice Stephen Breyer, to step down to ensure that Obama could nominate a younger justice with similar views. Lawyers who are close to the Obama administration have made the same argument, but more quietly.

In one sense, it's already late for that, since the Senate will be in Republican hands come January, making confirmation more difficult.

Still, the picture would look worse yet for the Democrats if a Republican should win the presidential election in 2016. A retirement then by a liberal justice would allow the appointment of a more conservative justice and potentially flip the outcome in important 5-4 decisions in death penalty, abortion, even gay rights cases in which the liberal side sometimes prevails.

Ginsburg has repeatedly rebuffed suggestions that it's time to step down. She remains one of the court's fastest writers and has continued to make frequent public appearances around the country.

Stents are mesh scaffoldings inserted into about half a million people in the U.S. each year to prop open arteries clogged by years of cholesterol buildup. Doctors guide a narrow tube through a blood vessel in the groin or an arm, inflate a tiny balloon to flatten the blockage, and then push the stent into place.

___

Associated Press writers Nancy Benac and Lauran Neergaard contributed to this report.