I had my heart in my mouth.

我放了我的心思在我的嘴。

youdao

"Or the person might have had a very frightening experience, like being chased by an angry dog. He might say:" I had my heart in my mouth.

又或者某人受了惊吓，比如说被一条愤怒的狗追赶，他可以说“我的心都跳到嗓子眼了。”

youdao

My heart was in my mouth when I walked into her office.

我走进她的办公室时，心提到了嗓子眼。

《柯林斯英汉双解大词典》

He might say: "I had my heart in my mouth."

VOA: special.2010.06.20

My heart jumped into my mouth, for Scoresby was the next in line to take his place.

VOA: special.2010.03.27

"My heart was in my mouth, but I never gave up and just kept pushing and pushing, " he said.

BBC: Hamilton targets title hat-trick

There was nothing I could do, I was just trying to keep the car on the track and my heart was in my mouth.

CNN: F1 champion Hamilton ecstatic after Brazil drama