iPods Teach Docs to Recognize Heartbeats

Two years ago, Dr. Michael Barrett had a cool idea for taking his Temple University medical school classes into the high-tech future—or so he thought. He'd been teaching students to recognize the distinctive sounds of heart murmurs by playing recordings in class. "We'd give a one-hour lecture, play each sound for them, and say, 'That's your murmur, guys,'" he recalls. "Then they'd look at us blankly and file out of the room." Barrett's idea was to give his students CDs loaded with heart sounds to listen to at home. Alas, this proposal garnered equally blank looks from his students. "I was surprised," he says, "but they were like, 'Dr. Barrett, nobody listens to CDs anymore.'"

Barrett didn't own an iPod at the time, and he says that "90 percent of practicing doctors over 30 probably still don't." But his students do, and today they have beat-heavy tracks like "innocent systolic murmur," "aortic regurgitation" and "mitral stenosis" at the top of their playlists. They've put the so-called "heart songs" on repeat and listened to them at the gym, on their commutes, while walking around town. In the process, apparently, they've become better doctors.

This weekend at the annual conference of the American College of Cardiology, Barrett reported that cardiology (or at least one component of it) can be taught by iPod. After listening to MP3s of 400 or more heartbeats, manipulated to sound either healthy or abnormal, students were able to easily identify sounds in patients that might signal trouble. Before testing out Barrett's program, another group of internists managed to identify only 40 percent of murmurs correctly; afterwards, they got 80 percent right. "Usually, the first time you try to listen for a heart murmur you're lucky if you hear a heartbeat at all," says Jodi Washinsky, a fourth-year med student at Tufts. "But this has really helped me. I've found myself picking up a lot of murmurs in patients, now that I actually know what I'm listening for."

What's amazing isn't necessarily that doctors are using iPods as teaching tools—it's that they've taken so long to catch on. In 2005, Duke University gave all incoming undergraduates their own iPods, and many other schools have signed up for Apple's "iTunes U," which allows them to download podcasts of lectures and other course materials. But medicine, particularly cardiology, has lagged behind, says Barrett. "We as cardiologists haven't done a very good job of teaching these heart sounds to medical students and even residents," he says. "In the past, we would have just played short recordings in class, or we might have waited for a patient to show up with a perfect murmur and then we'd line all the students up in front of him. If they were lucky, they'd get to listen for 30 seconds each."

That approach just doesn't work, says Barrett, because the key to learning heart murmurs is repetition. "Learning these sounds is not an intellectual skill. It's a technical skill, like tying knots," he says. "And the way you learn a technical skill is by repeating it, and repeating it, and repeating it." Barrett surveyed students and found that 400 repetitions of a heartbeat were enough to drill into a student's head the particular rhythm of a murmur: the "lub-dub" of a healthy heart, the "lub-whoosh" of aortic regurgitation, or the "lub-rumble-dub" of aortic stenosis. But 400 heartbeats were too much to ask of a real, live patient, says Barrett: "They won't tolerate sitting there that long."

Instead, Barrett put together computer-generated simulations of those noises, which were clearer and easier to hear than the heartbeat of an actual patient. Then he formatted them into individual MP3 files, introducing and explaining each one. The recordings were an immediate hit with students. "Time is obviously a problem for medical students, so anything you can learn outside the hospital is great," says Washinsky, who will enter an internal medicine residency next year. "I have a half-hour commute, so I was listening to this a lot on the train, and at home too, if I was going to bed and didn't feel like watching TV."

Not only were the "heart songs" convenient, they worked. Barrett has mostly given them to younger docs and students, but he says older physicians can also benefit from adding the MP3s to their music libraries. He'll be testing out willing participants' abilities at the conference this weekend, and for those who don't make it there, the ACC offers a collection of recordings for download on its Web page. (For those who still haven't broken down and bought iPods, the recordings also come as Barrett originally envisioned them, in CD form.) Even those of us without stethoscopes can learn a heart song, well, by heart, says Barrett. "I had a feeling this was a skill you could pick up without any medical background at all," he says, "so I secretly put a marketing major in our classes and had him learn these heartbeats on his iPod. At the end of the class he scored equal to any of the med students. This kid couldn't spell 'mitral regurgitation,' but he could learn to recognize it."