Comparison Of Cardiac Auscultation To Echocardiography

The physical exam, along with the patient's history, ha's been one of the true hallmarks and mainstays of the medical profession. It has provided information about the patient and their diseases that could be not obtained in any dh er fashion. However, with the advent of new technologies, methods of obtaining information have expanded enormously and the information obtained has been made more precise and accurate. Echocardiography is one of these technologies. By using sound waves emitted by a probe that is placed on the patient's chest it enables us to look at and into the heart in ways never thought imaginable just fifty years ago and has been an invaluable tool in our quest to understand and diagnose cardiac pathology. Despite its value, echocardiography has obviously not replaced the physical exam, as no test has. It has served as a supplement to the exam adding, clarifying, and, on occasion, enlightening. Comparisons between echocardiography and auscultation have been made for various heart sounds. When compared to catheterization pulsed doppler echocardiography has been shown to be much more sensitive and specific than auscultation in detecting valvular pathology. In a study by Jaf f e et al patients with suspected aortic and mitral disease were evaluated using clinical findings (history, exam, radiography, EKG), doppler echocardiography, and catheterization. They found echo to be significantly more accurate, sensitive, and specific than clinical evaluation in assessing valvular pathology, with improvement in clinical evaluation results when confidence of disease was high. They also found echo to be highly accurate when compared to catheterization. Aortic insufficiency has been studied by several groups and doppler echo has been shown to be at least ninety five percent sensitive and ninety percent specific in AI. Auscultation, on the other hand, has much lower effectiveness but is at least as effective as M mode and 2-D echo. Rahko showed doppler to be much more sensitive than auscultation in detecting valvular regurgitation, with this being especially true for mild regurgitation.6 Hoffman and Burckhardt showed doppler to be effective at evaluating ill defined systolic murmurs, showing an overall diagnostic accuracy of eighty nine percent.7 In a retrospective chart review Olive and Grassman found that exam findings suggestive of mitral valve prolapse are not sensitive or specific for positive echo findings, a finding that was in agreement with other previous studies. Contributing to this evidence of echocardiography's superiority over auscultation may bt the deterioration and inadequacy of the cardiac exam in the day of high technology. A study by Margione et al examined the proficiency of the physical exam of medical students, medical residents, and cardiology fellows.9 Using prerecorded audiotapes of the sounds of various cardiac pathologies, they found that the exams of students and residents were woefully inadequate, and those of the fellows were not much better. In addition to this they found that within training programs there is very little emphasis on teaching the skill of auscultation and suggest that more time and effort be spent teaching exam skills at the bedside so that the art of medicine is not lost. A large trial evaluating all murmurs in a prospective manner is lacking. The above studies consist of a small sample size of patients and have several flaws including selection bias of only patients with murmurs on physical exam (therefore altering sensitivity and specificity), interpretation bias with the use of retrospective analysis, evaluation of presence or absence of one or two types of valvular pathology, and the use of artificial pre-recorded audiotapes for determining recognition of murmurs. Our study would be the largest to date, numbering at least 150 patients obtained from consecutive admissions to the cardiology service at Columbia-Presbyterian Medical Center. It would include patients with known coronary artery disease and those being evaluated for chest pain, syncope, dyspnea, etc. The study will be conducted prospectively and double-blinded to the investigators. In