This is absolutely ingenious:

Patients rely on their physicians to recognize signs of trouble, yet for common heart murmurs, that ability is only fair at best. Fortunately, the solution is simple: listening repeatedly. In fact, intensive repetition -- listening at least 400 times to each heart sound -- significantly improved the stethoscope abilities of doctors, according to a study presented today at the American College of Cardiology's annual meeting.

After demonstrating last year that medical students greatly improved their stethoscope skills by listening repeatedly to heart sounds on their iPods, lead investigator Michael Barrett, M.D., clinical associate professor of medicine and cardiologist at Temple University School of Medicine and Hospital, set out to test the technique on practicing physicians.

During a single 90-minute session, 149 general internists listened 400 times to five common heart murmurs including aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation and innocent systolic murmur. Previous studies have found the average rate of correct heart sound identification in physicians is 40 percent. After the session, the average improved to 80 percent.

Proficiency with a stethoscope -- and the ability to recognize abnormal heart sounds -- is a critical skill for identifying dangerous heart conditions and minimizing dependence on expensive medical tests.

"It's important to know when to order a costly echocardiogram or stress test," said Barrett. "Plus, internists are now tested on this skill for board recertification. Requirements for residents and other specialists are sure to follow."

Listening to the heart, known as cardiac auscultation, is, Barrett believes, a technical skill and therefore best learned through intensive drilling and repetition, not by traditional methods, usually a classroom lecture or demonstration in medical school and then on the job.

"You don't build this proficiency by osmosis," Barrett said. (Emphasis mine.)

Auscultation -- or listening to the heart or lungs or bowels with a stethoscope -- is one of the most important skills that medical students and young doctors learn. It's cheap, it's quick, and if the person knows what they are doing it is better than a CT or an MRI.

It is also one of the hardest skills to learn. One of the problems is that it takes a lot of practice. The other is that -- as any medical student will tell you -- it is fine and good to be able to listen in a closed room with no other ambient sounds. It is another matter entirely to listen to someone's heart in a ward filled with shouting people.

Anyway, I think this is just genius. I would even go one step farther. Listen to your iPod on the subway or on the way to work. It will get you used to tuning out ambient noise while you listen.

Here are some sample sounds from the press release (mp3 files all):

Normal heart -- the first bump is the mitral and tricuspid valves closing, the second is the aortic and pulmonic valves closing, the time in between the two is systole (ventricular contraction), the other time is diastole (artial contraction)

Heart murmur -- I am going to get totally screwed by this, I can feel it, but I am pretty certain that this is a pansystolic murmur suggestive of mitral regurgitation (among other things). We'll how long it takes someone to tell me I am wrong...

Heart lesson -- Here is an example of one of the lessons narrated by Barrett.

You can get the full set of mp3s here.

An excellent article on heart murmurs is available on wikipedia.