Pope Benedict reportedly had a heart procedure late last year that left him wondering whether he's healthy enough to continue leading the world's one-billion Roman Catholics.

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An Italian business newspaper is reporting today that doctors replaced the battery in a pacemaker that was implanted after then-Cardinal Josef Ratzinger suffered a stroke more than a decade ago.

The 85-year-old Pontiff stunned the world yesterday when he announced he will resign as Pope at the end of this month. It will be the first papal resignation in almost 600 years.