The Teaching and Practice of Cardiac Auscultation during Internal Medicine and Cardiology Training: A Nationwide Survey

there is already plenty of evidence to show that we are in danger of losing our clinical heritage and of pinning too much faith in figures thrown up by machines. Medicine must suffer if this tendency is not checked (Paul Wood. January 1950 [1]) We live in times of sophisticated and expensive diagnostic technology. Computed tomography, magnetic resonance imaging, ultrasonography, and nuclear medicine have enormously expanded our ability to define anatomic and physiologic abnormalities but at the price of an ever-increasing cost of health care. The use of these tools may have also rendered our trainees overconfident in technology and, as a result, may have weakened their physical diagnostic skills. If such a weakness actually exists, it would contrast sharply with recent surveys showing that internists in practice consider physical examination one of the most valuable skills acquired during internal medicine training [2, 3]. It would also lead physicians to rely too greatly on diagnostic technologies that are unnecessary, expensive, and potentially dangerous. Cardiac auscultation, long the symbol of all bedside diagnostic skills, provides the best example of the effect that modern technology and current training practices may have had on physical diagnosis. Recent reports have reiterated the effectiveness and importance of cardiac auscultation [4, 5]. Nevertheless, echocardiography and color Doppler imaging studies may offer accurate and objective information when compared with the feeble signals perceived through a stethoscope. The use of these expensive technologies is also encouraged by their greater financial compensation in contrast to that for physical examinations, however skillfully performed. In addition, the American Board of Internal Medicine does not explicitly assess auscultatory proficiency of internists as part of the certification examination. Thus, internal medicine trainees' interest and proficiency in cardiac auscultation may be waning. Physicians with many years of practice and certifying boards now express concern with the physical examination skills of trainees. Yet, only a few published studies have tried to support or refute these concerns. A recent study indicated that internal medicine trainees may have difficulty establishing a correct diagnosis only on the basis of the cardiovascular physical examination [6]. This study, however, was limited to only one medical center, only one level of training, and only three preprogrammed simulations. To overcome these limitations, we designed a study that could determine whether cardiac auscultation is still viewed as important for the practicing physician and that could evaluate the proficiency and teaching of cardiac auscultatory skills. Methods Survey of Program Directors A one-page questionnaire, accompanied by a letter from two of the investigators, was mailed to the directors of all 659 U.S. accredited internal medicine residency and cardiology fellowship programs. Directors' addresses were gathered from the green book directory of approved residencies and fellowships (Directory of Graduate Medical Education Programs. American Medical Association, Chicago, 1990). Data were collected by mailed questionnaire between August and December 1990. All nonrespondents were sent a second copy of the survey 1 month after the initial letter. The questionnaire's first section collected background information about the directors and their programs. The directors were asked to answer items concerning their age and type of subspecialty, the characteristics of their programs (number of trainees and university affiliation), and whether their residencies or fellowships offered any structured teaching of cardiac auscultation in their programs. Although clinical skills such as cardiac auscultation should be primarily acquired at the bedside (through experience with patients and direct supervision by attending physicians and more senior trainees), we believe that this traditional form of teaching might have become lost in our age of rounds conducted in halls and conference rooms. Thus we deliberately asked the directors to comment only on the presence of structured teaching in their training programs and to exclude bedside teaching during ward rounds. Lectures, seminars, and audiovisual teaching modalities (such as audiotapes) were included in our definition of structured teaching. Program directors were also asked to indicate their field of interest and practice and, on this basis, were classified as either invasive (if their subspecialty was cardiology, pulmonary medicine, critical care, or gastroenterology) or noninvasive (if their subspecialty was endocrinology, rheumatology, infectious diseases, allergy and immunology, geriatrics, nephrology, hematology/oncology, or general internal medicine). Program directors who were cardiologists were similarly asked to classify themselves as invasive, noninvasive, or both depending on the type of cardiology they practiced. The questionnaire's second section asked for the directors' opinions regarding three statements: A) Cardiac auscultation is an extremely important tool for any practicing physician; B) More time should be devoted to the teaching of cardiac auscultation during internal medicine [or cardiology] training; C) The recognition of the following cardiac events is extremely important and therefore should be mastered by any practicing physician. The third statement contained a list of 11 cardiac events: 1) S3 gallop, 2) S4 gallop, 3) early-systolic click of aortic ejection, 4) mid-systolic click of mitral valve prolapse, 5) opening snap of mitral stenosis, 6) pericardial friction rub, 7) systolic murmur of mitral regurgitation, 8) systolic murmur of aortic stenosis, 9) diastolic rumble of mitral stenosis, 10) diastolic murmur of aortic regurgitation, and 11) continuous murmur of patent ductus arteriosus. The directors expressed their opinion about all three statements, including the 11 events, by choosing along a six-step scale in which 1 indicated strong agreement. For clarity, all the directors' scores were recoded into a six-step scale in which 1 = strongly disagree and 6 = strongly agree. Statistical Analysis We decided to carry out most of the analyses of the two program types separately because medicine and cardiology respondents were sometimes from the same program. Analysis consisted of chi-square tests to relate dichotomous and nominal variables, Mann-Whitney U and Kruskal-Wallis rank tests to compare two groups or more than two groups on the several scale measures, and Spearman rank correlations to correlate scales and other numeric variables. For a few analyses, the comparison of cardiology and medicine programs was critical. The analyses were by chi-square and Mann-Whitney U tests, even though the data were a mix of repeated measures and nonrepeated measures, because some of the respondents were from the same institution. Nonrepeated measures methods were used because of the essentially independent functioning of such programs and the absence of any good alternative method of analysis. To compare the directors' attitudes toward the cardiac murmurs and cardiac extra-sounds of our list, we created a mean importance rating for each set of sounds and for each respondent. Thus we created a murmur mean for the five murmurs and a sound mean for the six extra-sounds. Analysis of these two means was carried out by paired t-test and ANOVA. Auscultatory Proficiency among Physicians-in-Training We assessed the auscultatory skills of 203 trainees. Participants comprised 187 internal medicine residents and 16 cardiology fellows. In addition, we included in our assessment 49 third-year medical students who provided a comparison for the performance of physicians-in-training (Table 1). Of the 203 trainees, 188 were from eight university-affiliated programs in the Philadelphia area that offered no structured teaching of cardiac auscultation. These eight internal medicine and cardiology programs were based at the Medical College of Pennsylvania, the Hospital of the University of Pennsylvania, Temple University Hospital, Hahnemann University Hospital, and Thomas Jefferson University Hospital. Also included in our evaluation were 14 students and 15 internal medicine residents from Georgetown University in Washington, DC. This program was selected because in our survey we found it to be one of the few that devotes many hours to teaching cardiac auscultation. Table 1. Number of Participants in the Proficiency Test Distributed by Program and Year of Training The evaluation of auscultatory proficiency was arranged as a 1-hour patient-management conference, incorporated in the teaching schedules of the various programs. The first half of the conference tested the proficiency of trainees and the second half reviewed the various cardiac sounds and murmurs used in the test. The evaluation instrument consisted of 12 cardiac events directly recorded from patients and selected from a pool of 250 sounds found on commercially available audiotapes. Each event was digitized into a microcomputer (Macintosh SE30, Apple Computer Inc.; Cupertino, California), its waveform analyzed (MacRecorder, Farallon Computing; Berkeley, California), and 12 events finally chosen on the basis of the purity of their sounds and good reproduction of findings typical of the corresponding disease process. These 12 events included all those events that the program directors had been asked to evaluate for clinical importance, and, additionally, the systolic and diastolic murmurs of aortic stenosis and insufficiency. Each selected event was recorded on a Hi-Fi Cassette Deck (CR W85, Fisher Corporation; Chatsworth, California) and played back for 1.5 minutes to the trainees using stethophones (P.N.30-002 Humettrics Corporation; Chicago, Illinois) and a Hi-Fi audiocassette player (Marantz PM430; Chatsworth, California). Participants were told the chest area of re