have heart stand still
have (one's) heart stand still
To experience very strong emotions, especially excitement, nervousness, or fear, such that it feels as though one's heart stops beating for a moment. I swear, I had my heart stand still the moment my wife began walking down the aisle on our wedding day. I have my heart stand still whenever the principal calls me into her office, even if I know I haven't done anything wrong!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
have one's heart stand still
Fig. an expression said when one's heart (figuratively) stops beating because one is shocked or is feeling strong emotions. I had my heart stand still once when I was overcome with joy. Lovers—at least the ones in love songs—usually say their hearts stood still.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.