I've seen this movie overseas in the early 1980's, under its itaian title "A Venezia muore un'estate".
The love scenes are tender yet passionate, accompanied by venetian soloists music. It's the story of a strong, firm link that will keep a husband and a wife together during and after her artificially induced sleep. She gets hybernated due to an illness that had no cure at the time. While dealing with the pain with the help of Irene, a common friend of theirs, David (The husband) remenisces this beautiful story since its beginning: The pictures taken in Venice's Piazza San Marco, making love to her, their numerous walks.
She will wake up after twenty years and her love for him is still the same. Albeit their strong feelings and the fact that they are together again, David has aged and won't have enough time to make up for the years he spent apart from his loved one.
I have been looking for this movie for the longest time without any success. If there is anyone who can point me out to some websites that might have this movie please let me know. Thanks.