How Free Text in 911 Calls Helps Spot Heart Emergencies Early

When someone calls emergency services with chest pain or trouble breathing, the dispatcher has to act fast. Usually they only have a few checkboxes and a short code to work with. That limited info can make it hard to tell who needs the most help right away.

Sometimes the dispatcher types out a full sentence describing what they hear. These free‑text notes can contain extra hints like the exact words the patient uses or background noises. Researchers have not yet figured out how useful those notes are for early risk checks.

To find out, a team looked at all emergency calls from Nanning, China, between 2021 and 2025. They picked adult callers whose complaint matched words like “chest pain” or “shortness of breath”. After removing junk or incomplete records, they kept 38,523 calls that had the free‑text story attached.

For a realistic test, they used the calls from 2021‑2024 (about 28,300) to train a computer model that reads the text with natural language processing. Then they checked if adding the narrative improved predictions of serious outcomes compared to using only the standard checkboxes.