Conversation so far:
What did Lowell Thomas do?
Thomas's most amusing on-air gaffe.
What is this?
He was reading a story "cold" (going on the air without pre-reading his copy, contrary to his usual practice.
WHat did he say?
She suffered a near fatal heart attack".
The line came out of Thomas's mouth as.
What actually came out of his mouth?
line came out of Thomas's mouth as "She suffered a near fart ...
err fatal heart attack".

Question: What did he do?
Self-contained rewrite: What did Lowell Thomas do after the gaffe?