Code Red released the US version.
"...English language version differs significantly from the original Italian version, Il medaglione insanguinato, in numerous respects. The US print contains a different, much tackier opening titles sequence; Elmi's opening nightmare/flashback is cut and restructured considerably with musical alterations and a superimposition of her sleeping face added throughout; some of Johnson's dialogue with an occult expert played by Lila Kedrova is trimmed down; two entire scenes (totalling around three minutes) are cut following the mallet murder in which Johnson is interrogated by the police and then compares his story with Cassidy's; and the final voiceover from Elmi questioning the necessity of evil is dropped from the soundtrack. On the other hand, the English version also adds some footage not in the Italian cut, as Johnson's Diabolical Arts program is shown in much more detail and an additional scene is included with Elmi exploring the new villa upon her arrival in Italy." (Mondo Digital)
I own the Italian version as well btw.