UNDERSTANDING PEDIATRIC HEART SOUNDS By Steven Lehrer. 230 pp., illustrated, with accompanying audiocassette. Philadelphia, W.B. Saunders, 1992. ISBN 0 7216 2387 5.
One of the joys of pediatric cardiology is the formulation of a clinical impression based only on the history and cardiovascular examination, perhaps supplemented by an electrocardiogram and a chest x-ray. For cost effectiveness and efficient use of resources, screening and referrals must be based on these cornerstones of clinical assessment. It is therefore timely and appropriate to reiterate the importance of bedside clinical evaluation. Lehrer's book emphasizes that auscultation is a diagnostic skill that still has great influence in the investigation of the pediatric patient thought to have heart disease.
Understanding Pediatric Heart Sounds is a well written, succinct book combined with a 20 minute audiotape. It contains 15 chapters, the first 3 of which concern anatomy and physiology, physical principles of auscultation, and an overview of the history and physical examination in pediatric cardiology. A brief chapter explains the methods of phonocardiography and external pulse recordings. The remaining chapters extensively detail the auscultation of normal heart sounds, abnormal cardiac sounds, and murmurs. The differential diagnosis of murmurs and the murmurs characteristic of both common and complex entities are presented. The relatively brief audiotape includes normal and abnormal heart sounds, as well as examples of murmurs common in young patients. For maximal clarity, the use of a stethoscope placed near the speaker is recommended when listening to the tape.
The major strengths of this book are its crisp, clear cut, and readable style and its thorough descriptions of auscultatory findings and of the mechanisms of cardiac sounds and murmurs. The integration of the text with ample, high quality illustrations allows the reader to proceed at a brisk pace. The reference list includes many classic works, and the index is comprehensive. On the audiotape, the reproductions of heart sounds are excellent. On the other hand, many of the murmurs are of only fair quality and are not always representative of clinical findings in young patients. However, having tried many times to simulate or present common murmurs in an audio format, I have great empathy for authors who try to reproduce them accurately. We live in an age of incredible electronic sophistication, but our ability to record or produce heart murmurs has lagged well behind our skill at other endeavors. Learning the art of auscultation requires accurate information, tutelage, and repetition. The reader-listener might be better served by paying more attention to the easy to follow text and the well produced heart sounds and less to the simulated heart murmurs.
Although the style is consistent, chapter 5 may be somewhat confusing to both novice examiners and experienced practitioners. It presents a revision of traditional areas of auscultation. Instead of referring to the well known mitral and tricuspid areas, the author uses a format that includes left and right ventricular and left and right atrial areas, as well as the traditional aortic and pulmonary areas. Although it has some potential benefit for enhancing communication, this format has the drawback of substantial overlap between these regions. Furthermore, the author states subsequently that the cardiac structures in congenital heart disease may be "displaced from their usual locations." Instead of a concentrated focus on specified areas of auscultation, a description of murmurs in relation to well-known landmarks, such as the mid left sternal border, the lateral second left interspace, and the suprasternal area, might be more effective. The technique of inching, moving the stethoscope in small increments over the entire anterior chest and also over the back, is described briefly, but it deserves emphasis. Also, the technique of dissection, which involves concentrating on one portion of the cardiac cycle or one heart sound to the exclusion of others, is often beneficial but is not discussed in the text.
A few minor omissions include the low pitch of innocent carotid bruits, the left lateral displacement of the aortic closure sound in congenitally corrected transposition of the great vessels, and the diffuse nature of continuous murmurs in patients with tetralogy of Fallot with pulmonary atresia and pulmonary blood flow derived from aortopulmonary collateral vessels. The narrow split of the second sound in patients with pulmonary hypertension is shown in a figure but is not mentioned in the text. In addition, the auscultatory variations of murmurs due to ventricular septal defects should have received more extensive review.
Despite these minor criticisms, I found Lehrer's work refreshing, concise, and a pleasure to read. The author's clear style makes the book, and at least a good portion of the audiotape, eminently suitable for students, house staff, and practitioners who wish to enhance their listening skills for pediatric cardiovascular examination. I wholeheartedly agree with the author that auscultation should not become a lost art.
J. PETER HARRIS, M.D.
Pediatric Heart Sounds
Understanding Pediatric Heart Sounds, by Steven Lehrer, 230 pp, with illus, and one audiocassette, paper. ISBN 0 7216 2387 5, Philadelphia, Pa, WB Saunders Co, 1992.
This 230 page soft cover book, by Steven Lehrer, MD, is a comprehensive review of the literature related to heart sounds. The author writes simply and clearly. The book is almost an abbreviated text of pediatric cardiology and could be titled "Pediatric Cardiovascular Assessment and Diagnosis." Much of the material has been previously covered in such books as Pediatric Cardiology for Practitioners, by M. K. Park, and two books by J. K. Perloff, The Clinical Recognition of Congenital Heart Disease and Physical Examination of the Heart and Circulation.
The figures and tables are almost exclusively reproduced with acknowledgment from previous publications. Although little new information is included, the manner in which the author presents the material is outstanding and goes much beyond the understanding of pediatric heart sounds. The references at the end of each chapter are extensive and excellent for the student who desires to pursue the subjects in great detail.
The chapter on heart murmurs will be particularly helpful for a better understanding of the origins of such sounds. As pointed out by the author, functional benign heart murmurs are common in children, yet perplexing for the practitioner to identify. Most care givers feel uncomfortable with any murmur that is grade 3 in intensity and will refer the child to a pediatric cardiologist for assessment.
The glossary is very beneficial, as is the chapter "Transcript for the Supplemental Tape." The tape should be most useful to the sincere student of auscultation. With the faster heart rates of younger children, the use of one's stethoscope under the tutored wisdom of an experienced pediatric cardiologist is indispensable!
The first three chapters of this book will be most helpful to all medical students. Family practice and pediatric residents and pediatric cardiology fellows will find the book full of good information in summary form. For the practicing care giver, the book will be an excellent reference text for refresher information.
Antoni M. Diehl, MD
Understanding Pediatric Heart Sounds
Although I am a paediatric cardiologist, I have never really understood paediatric heart sounds. I was born into the subject in 1980 with an ultrasound machine attached to my right wrist and could not wait to dispense with the guesswork that auscultation seemed to entail. Now I wear my stethoscope only for decoration or to add a touch of old fashioned authenticity for suspicious parents. The title of this publication seems quaint for the 1990s, at a time when technology has taken over from the stethoscope and a child with a complex heart malformation can be evaluated and surgically treated without the bell ever touching the chest.
Bereft of his portable echo machine, Lehrer has put together a package that is ideal for both undergraduates and postgraduates in paediatric training. The reasoning behind children's heart sounds and murmurs is laid out clearly and Lehrer is obviously a skilled, thoughtful, and experienced auscultator. I recommend especially the chapter on systolic murmurs to many of my consultant paediatric colleagues who remain unable to distinguish a classic innocent murmur from that of a ventricular septal defect. Many children arrive in our clinics having been referred for unnecessary echocardiograms. On several occasions I became concerned that the author had lost touch with modem terminology; endocardial cushion defects are not commonly described as such nowadays, being referred to as atrioventricular septal defects. Also, to talk of surgical pulmonary valvotomy, when the established treatment for pulmonary stenosis for nearly ten years has been a balloon valvuloplasty, seems strange. There is a brief, if slightly naive, overview of some major heart malformations, but this is perfectly suitable for undergraduates.
The tape provides good examples of the different types of heart sounds and murmurs found in children. I was surprised that one of the most common, that of pulmonary stenosis, was not included. However, familiarity with the limited nature of possible diagnoses should dispel the panic often felt by undergraduates and even, in some instances, postgraduates when asked to auscultate a child's heart.
The Lancet 1992; 340:1147. pdf
Understanding Pediatric Heart Sounds would be more appropriately titled, “Interpreting Pediatric Heart Sounds," for it comes equipped with one of the clearest tapes for this area of assessment. The tape cassette complements the text but only addresses the sounds themselves.
The book and tape are relatively easy to use. They provide a comprehensive presentation of the heart sounds. However, while most conditions are addressed that lead to abnormal heart sounds in children, there is only a cursory presentation of the physiology that results in the sounds. The authors assume a prior knowledge base in cardiac anatomy, physiology, and pathophysiology. References are from the 1970s and 1980s.
This useful text was designed for physicians and nurses at the post-baccalaureate level who work with children. The author does provide an update on physical assessment of the cardiac system and compares traditional assessment areas for auscultation to proposed revised ones. This may be helpful to nurses currently in practice.