Heart-to-ear: Dal medical professionals contribute to new diagnostic tools
Teaching Heart Auscultation fills a void in medical academic study
Kevin Hartford - October 31, 2011
The stethoscope: a mandatory addition to any Halloween doctor costume, but not the first thing that springs to mind when one thinks of modern medicine.
“Is it a diagnostic tool or a fashion accessory?” asks Dr. John Finley, pediatric cardiologist with Dalhousie and the IWK Health Centre. “That’s the question.”
Dr. Finley is editor and co-author of a new book, Teaching Heart Auscultation to Health Professionals, which details instructional methods for distinguishing between normal and abnormal heart sounds using a stethoscope. Auscultation is a term for listening to heart and lungs as a means of diagnosis.
Teaching Heart Auscultation is intended to fill what Dr. Finley sees as a void in current medical academic study. “The idea here is to get teachers to look at the way in which auscultation is taught and revise their teaching so it’ll be more effective,” he says. “There are plenty of books on what heart sounds mean, but no books on how to teach students exact methods of listening.”
The book features 11 contributors, four of which are associated with Dalhousie: Dr. Finley; Rachel Caissie, associate professor in the School of Human Communication Disorders; Brian Hoyt, manager of the Core Facility for Health Research Data and Systems Management; and Dr. Douglas Roy, a retired pediatric cardiologist from the Faculty of Medicine.
“We think of hearing as a sense, but listening is a skill, and a skill can be improved with practice,” says Dr. Caissie, who holds a PhD in audiology, the study of impaired hearing. Her approach to heart auscultation is to “adapt techniques we use in audiology in which we train people with hearing aids and cochlear implants to make maximum use of what hearing they have left.”
Foremost among those techniques is the act of listening to multiple repetitions of varying sounds in order to recognize distinctions. “You really need to make repeated comparisons and many of the tools available commercially don’t address that issue,” says Dr. Finley. “Our research involves taking a series of recordings of heart sounds, both normal and abnormal, and mixing them up so that students have the opportunity to hear both and make comparisons many, many times.”
Every heart has something to say
A teaching tool comprised of over 50 heart sound recordings was developed by Drs. Finley and Caissie and Mr. Hoyt, and tested at both Dalhousie and the University of Western Australia (UWA) in Perth. Trials were done with 40 medical students and 30 non-medical students at Dal and 120 students at UWA. Pamela Nicol, a professor in UWA’s School of Pediatrics and Child Health, is one of the book’s contributors.
Auscultation is integral to detecting early-onset heart disease, says Dr. Finley. “Children have lots of heart murmurs. If you take a group of preschool kids, roughly 30 per cent will have a noise from the heart, but only one per cent of the group will actually have heart disease. You have to be able to distinguish between that normal murmur – we call it the musical murmur – and the abnormal murmur. Students using our protocol are able to make that distinction.” Without that ability, many children may be referred unnecessarily since their murmurs are truly normal.”
A new chapter for heart health in Canada
The book, which took over two years to complete, has been endorsed by the Canadian Cardiovascular Society and the Canadian Pediatric Cardiology Association. While at the 2011 Canadian Cardiovascular Congress meeting in Vancouver recently, Dr. Finley provided a copy of the book to every medical school in the country.
“Nobody before now looked at how it is that sounds are perceived and the strategies that could be used to improve recognition,” notes Dr. Finley. “The book reviews the current state of knowledge and how teaching has been done in the past, current means of assessment, and ways in which these new avenues can be explored. That’s what makes this book such a useful tool.”
Anyone interested in buying a copy should check the Dal Bookstore or contact Dr. Finley at firstname.lastname@example.org.