VATICAN CITY (CBSNewYork/AP) — Vatican officials revealed Tuesday that Pope Benedict XVI has a pacemaker and recently underwent surgery to have the battery inside the implanted device replaced.

Vatican spokesman Rev. Federico Lombardi said Benedict has had the pacemaker for years. He received the device before he became pope in 2005 to help regulate his heartbeat.

It also came out Tuesday that construction crews have been renovating a four-story building attached on the northern edge of the Vatican gardens for months and that only a handful of Vatican officials knew it would one day be Benedict’s retirement home.

The 85-year-old Benedict said Monday he was stepping down because he simply no longer had the strength in mind or body to carry on — a move that shocked Catholics around the world.

EXTRA: Read Full Text Of Pope’s Announcement

“This hasn’t happened in six centuries,” New York’s Cardinal Timothy Dolan said Monday. “I’m as shocked and startled as all of you.”

Hours after the pope made the announcement Monday, lightning was seen striking the dome of St. Peter’s Basilica.

Lightning strikes St Peter's dome at the Vatican on February 11, 2013 hours after Pope Benedict XVI announced he will be resigning.  (Photo by FILIPPO MONTEFORTE/AFP/Getty Images)

Lightning strikes St Peter’s dome at the Vatican on February 11, 2013 hours after Pope Benedict XVI announced he will be resigning. (Photo by FILIPPO MONTEFORTE/AFP/Getty Images)

Although no date for a conclave to choose the next pope has been announced, it must begin within 20 days of his Feb. 28 retirement. That means a new pope will likely be elected by the College of Cardinals by March 31.

The decision immediately raised questions about what Benedict would be called, where he would live and how that might affect his successor.

The Vatican’s senior communications adviser, Greg Burke, said Tuesday the fact that Benedict had chosen to live in a monastery is significant.

“It is something that he has wanted to do for a while,” Burke said. “But I think it also suggests that his role is going to be a very quiet one, and that is important so you don’t have a situation of — two different popes at the same time, and one influencing the other. “I think the obvious thing is when he says retirement, it really means retiring.”

As for his name, Burke said Benedict would most likely be referred to “Bishop of Rome, emeritus” as opposed to “Pope Emeritus.” Lombardi also said Benedict would take some kind of “emeritus” title.

By March, the weather may start to warm up and he should be able to enjoy the gardens and feed the goldfish in a pond near a statue of the Madonna where he often liked to visit.

Lombardi said Benedict would eventually return to the Vatican and live at a monastery inside the Vatican gardens. Asked if he might like to go somewhere else, Lombardi said the pope would feel “much safer” inside the Vatican walls.

The Mater Ecclesiae monastery was built in 1992, on the site of a former residence for the Vatican’s gardeners. Pope John Paul II had wanted a residence inside the Vatican walls to host contemplative religious orders, and over the years several different orders would come for spells of a few years, said Giovanni Maria Vian, the editor of the Vatican newspaper L’Osservatore Romano.

The last such order of nuns left the residence in October, and renovation work began immediately afterward, Vian told AP. He said Benedict had decided to retire last April after his taxing but exhilarating trip to Mexico and Cuba in March.

“Many people thought they were doing the renovations for new sisters, but it was for the pope,” Vian said. He said only a few people knew of the pope’s plans, yet the secret didn’t get out.

“That shows the seriousness and loyalty of the few senior Holy See officials who were aware,” he said — a reference to the 2012 scandal over leaked papal documents by the pope’s own butler.

Benedict’s last major public appearance at the Vatican will be during Ash Wednesday mass at St. Peter’s Basilica.

(TM and © Copyright 2013 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2013 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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