Given the design of the ironwork on the 19th century Ponte Borgoloco, which lies near the Campo Santa Maria Formosa, I am surprised the bridge is not covered in the love locks, which plague so many of Venice's ponti!
However, the scroll-work depicts three letter Vs rather than three hearts. The Vs stand for ViVa Vittorio. The letter E at the bottom stands for Emanuele, which gives us Viva Vittorio Emanuele (long live Victor Emmanuel), a reference to Vittorio Emanuele II di Savoia (1820-78), the first king of Italy, who reigned from 1861 until 1878.
Venice did not become part of the Kingdom of Italy until 1866.