This is just flat wrong. The second coming is stated in the Nicene and Apostolic Creeds, which Christian churches have been reciting for well over 1,000 years.
I'm a Presbyterian. The second coming is taught in our confession, the Westminster Confession of Faith, which was written in 1646 and has been the standard of Presbyterian doctrine ever since.
Similarly, the London Baptist Confession, written in 1689, teaches the second coming. The Augsburg Confession, the Confessional statement of Lutheranism written in 1530, also teaches the second coming of Christ. Article 37 of the Belgic Confession--the official confession of the Dutch Reformed church written in the 1560s--also explicitly teaches the second coming.
It would be hard to find a single mainstream conservative Christian denomination that didn't teach the second coming in the 1800s when Seventh-day Adventism started. I personally can't think of one, because denial of the second coming has always been considered heresy by Christians.