Archbishop Pietro Sambi, the papal ambassador to the United States since 2005, died Wednesday night apparently from complications related to lung surgery, according to the United States Conference of Catholic Bishops . He was 73. Sambi, who was based in Washington and had a long diplomatic career in the church, had been put on ventilation following lung surgery at Johns Hopkins Hospital in Baltimore two weeks ago. As apostolic nuncio for the United States, Sambi served dual roles as a leader in the church and a representative to the U.S.