Smart speakers are smart enough to turn on your lights, remind you when to put out the trash and even tell you when heating-oil levels get low in your basement tank.

And soon, possibly, they also might monitor your heartbeat without physical contact after researchers at the University of Washington developed an artificial-intelligence skill for speakers using Amazon’s Alexa or Google Assistant virtual assistants. As if these devices weren’t already smart enough, the researchers effectively turned a prototype smart speaker into a “short-range active sonar system,” according to their findings published March 9 in the peer-reviewed Communications Biology journal.

In the study, people sat within 2 feet of the smart speaker as a continuous, but inaudible, sound played. The sound bounced off a participant’s body, then back to the speaker, allowing the newly developed artificial intelligence system to detect individual heartbeats. A heartbeat creates such minute motion on the chest’s outer surface that the new system requires machine learning to assist the assistant by combining signals from the device’s set of microphones when identifying signals from both regular and irregular heartbeats. (The algorithm combines signals from all the speaker’s microphones.)

The researchers found the smart speaker performed similarly to conventional heartbeat monitors in tests using 24 hospitalized cardiac patients and 26 healthy study participants. After close to 12,300 measured heartbeats among the healthy participants, the median inter-beat interval was within 28 milliseconds of the standard monitor. Among the cardiac patients, with more than 5,600 measured heartbeats, the results were within 30 milliseconds of the standard.

Already, cardiologists are using smartwatches to monitor patients’ heart rate. (For more information, click here.)

“It helps me to see what treatment to use, or how a patient is responding to a treatment,” says Dr. Sumeet Pawar, a cardiologist with Hartford HealthCare’s Heart & Vascular Institute who practices in Mystic and Westerly, R.I.

Next up, maybe a choice: Smartwatch or smart speaker.