319 Can You Hear the S4? Medical Student Diagnostic Errors in Cardiac Auscultation.

Abstract

PurposeAlthough numerous studies have documented the declining ability of medical students to identify heart murmurs, no studies have examined why students make errors. We designed a study to compare medical students' documented cardiac exam findings with the diagnoses they assigned.MethodsAt the end of the third year of medical school, all medical students at our institution take a multistation clinical performance exam (CPX). Each station consists of a 15-minute standardized patient interaction followed by a 5-minute written exercise. During the 2005 CPX, one station consisted of taking a history from a patient with chest pain and performing a focused cardiac exam on a Harvey cardiac simulator. On the written exercise, students were asked to document their cardiac exam findings and provide a diagnosis. All students were randomized to one of two settings on the Harvey simulator: hypertension (HTN), which consisted of an S4 at the apex, and aortic stenosis (AS), which consisted of a crescendo-decrescendo murmur at the aortic area and an S4 at the apex.ResultsA total of 92 students completed the 2005 CPX-47 examined the Harvey on the HTN setting and 45 on the AS setting. Of those students listening to the HTN setting, only two students (4%) correctly identified the S4 gallop. Eleven students (23%) misidentified the S4 gallop as an S3 and four (9%) as a split S2. Of those listening to the aortic stenosis setting, 17 (38%) correctly identified the murmur. For both settings, 78 students (35 for AS and 43 for HTN) provided a complete description (location and character) of their cardiac findings and a diagnosis. Of those with complete descriptions, only 45% of students provided a diagnosis, which was consistent with their documented exam findings (both location and character of the heart sounds). For example, several students made a correct diagnosis of aortic stenosis yet described a holosystolic murmur at the apex, whereas other students correctly described a crescendo-decrescendo murmur at the aortic area but made a diagnosis of mitral regurgitation.ConclusionsSimilar to prior studies, overall cardiac diagnostic accuracy of third-year medical students is low. Although auscultation skills can explain some of the errors, many students assign diagnoses that are inconsistent with their reported physical exam findings. Further education appears necessary to improve the clinical decision-making when interpreting a cardiac examination and arriving at a diagnosis.