Pediatric Cardiac Auscultation (Multimedia-based booklet)
I. Germanakis
Pediatric Cardiac Auscultation. Multimedia-based booklet
Pediatric Cardiac Auscultation (Multimedia-based booklet)
Ioannis E. Germanakis Assist. Professor Pediatrics – Pediatric Cardiology Faculty of Medicine, University of Crete
Pediatric Cardiac Auscultation. Multimedia-based booklet First edition published in Greek under the title Καρδιακή Ακρόαση στην Παιδική Ηλικία. Εκπαιδευτικό εγχειρίδιο πολυμέσων 2010, Ioannis Germanakis English edition published under the title Pediatric Cardiac Auscultation. Multimedia-based booklet 2010, Ioannis Germanakis
ΙSBN: 978-960-9433-27-x Copyright 2010 by Ioannis Germanakis Irakli 18 Α, Mastabas, Heraklion Crete, P.O.B 71305 Dokimakis Publications http://www.bigbook.gr All rights reserved. No part of this publication can be reproduced, stored or transmitted in any form or by any means, electronic, mechanical, photocopying, recording without written permission from the author-publisher. Permissions may be sought from the author: E mail: germjohn@med.uoc.gr .
Pediatric Cardiac Auscultation. Multimedia-based booklet Preface The present e-book aims to cover an important teaching topic: the systemic approach to pediatric cardiac auscultation. This edition hopes to become a valuable tool not only for medical students during their clinical exercise, but also for general pediatricians and primary health care physicians, responsible for primary health care screening of infants and young children, as well as for cardiologists with a special interest in pediatric cardiology. Writing a book which aims to improve cardiac auscultation clinical skills is not an easy task. Clinical skills are acquired through long term practice, a process that no book can substitute. On the other hand, clinical practice alone, without the theoretical background of cardiac sounds physics and the supervision by an experienced physician, will result in very doubtful clinical performance. This e-book aims to a) briefly present the mechanical function of the heart and the physics of normal and abnormal cardiac sounds and b) to provide multimedia graphics as well as a “virtual� clinical practice environment, as a valuable addition to theoretical knowledge. The theoretical section includes a suggested systemic approach in performing and describing cardiac auscultatory findings, mainly based on temporal (within the cardiac cycle) and spatial (localization on the chest) characteristics of cardiac sounds. Further sound characteristics (frequency, temporal variation of intensity, duration and spatial extension) are presented in detail, allowing the reader to provide an accurate differential diagnosis based on clinical findings. The text is linked to the associated multimedia, with referrals to animations (d) and virtual cardiac auscultation cases (h). Animations display the mechanical function of the normal and abnormal (congenital heart disease) heart and the basis of the genesis of normal and abnormal heart sounds. Virtual cases, with links to sound files (digital phonocardiograms) obtained from real pediatric cardiology patients, allow readers to listen all standard auscultation sites as is the case in live auscultation. Furthermore, following post-processing of original sound files, additional sound files are included (help files), emphasizing the abnormal auscultatory findings, either through time selection or selective filtering of the frequencies of the original recording. With the hope that the present e-book will represent a helpful pre-clinical introduction, I would like to welcome you and wish you success in the magnificent world of pediatric cardiac auscultation!
Ioannis Germanakis
Pediatric Cardiac Auscultation. Multimedia-based booklet Acknowledgments The idea of writing this book is based on the warm acceptance and kind motivation of the medical students and primary health care physicians and pediatricians, participating in the multimedia based pediatric cardiac auscultation teaching courses supported by the Faculty of Medicine, University of Crete. With the hope that this edition will provide the theoretical knowledge and selected listening to a wider audience, I would like to thank them all. I am grateful to the teachers that supervised my first steps in pediatric cardiac auscultation, Prof. M. Bourgeois and S. Rammos, as well as to Prof. S. Sbyrakis†, D. Kececioglu, S.Dittrich, M Gatzoulis and P.E Vardas, for their support in completing pediatric cardiology training. I would like to thank Prof. M. Kalmanti and all Faculty members for their support in establishing innovative approaches in pediatric cardiology teaching for our students, Prof. G. Varlamis and E; Petridou, for their enthusiasm to provide multimedia based teaching to pediatric residents throughout Greece. Hellenic Pediatric Society for taking under its auspices all associated teaching activities; Prof. K. Schmidt, U. Salzer, S Dittrich and J. Stein for further supporting modern pediatric cardiology teaching for medical students in EU. I would also like to thank all students and research fellows, for their great enthusiasm in supporting a large scale heart disease screening among school children on Crete, by using remote digital auscultation. Their comments were as valuable as was the technical assistance by A. Valahis and C. Neophytou in post-processing of sound files. Acknowledgments to N. Anagnostatou for English proof-reading. Finally I would like to thank families and children from which the anonymized sound files were selected, for their kind contribution. At last but not least, I would like to thank my beloved Anastasia, our sons Manolis and Giorgos and our parents, for their unlimited support and patience during the writing of this book.
Pediatric Cardiac Auscultation. Multimedia-based booklet
Contents Introduction ........................................................................................................... 1 The stethoscope ................................................................................................... 3 Cardiac sounds ..................................................................................................... 4 Heart mechanical function .................................................................................... 6 Normal cardiac sounds ........................................................................................ 9 Abnormal cardiac sounds ................................................................................... 12 a. Abnormalities of cardiac sounds.................................................................. 12 b. Additional abnormal cardiac sounds............................................................ 14 Timing .......................................................................................................... 15 Systolic sounds ........................................................................................ 16 Diastolic sounds ....................................................................................... 20 Continuous sounds .................................................................................. 22 Intensity ....................................................................................................... 23 Frequency .................................................................................................... 23 Temporal variation ....................................................................................... 24 Localization .................................................................................................. 25 Innocent murmurs ............................................................................................... 28 Complete physical evaluation ............................................................................. 29 History................................................................................................................. 30 Evaluation of neonates ....................................................................................... 31 Epilogue .............................................................................................................. 31 References ......................................................................................................... 32
Pediatric Cardiac Auscultation. Multimedia-based booklet INTRODUCTION Since the establishment of medicine as a science through observation and logical thinking by Hippocrates, thorough physical evaluation along with a detailed history taking still represent the basis of correct medical practice. Following history taking, physical “clinical” evaluation represents the initial and of paramount importance medical action, where the doctor using his senses (eyes, ears, hands) tries to detect which systems or organs of the patient are affected by the disease. Unfortunately, modern technological advances in medical imaging resulted in the misconception that physical evaluation is probably nothing more than a historical and useless medical task, which results in wasting of time of the modern high-tech and always busy doctor. However, the results of even the most advanced medical imaging technique have to be interpreted by a qualified physician. Providing a justified differential diagnosis based on history and clinical evaluation prior to imaging, both reduces the extent of imaging as well as improves its diagnostic accuracy. A doctor who requests whole body imaging or determination of all available biomarkers irrespective of the clinical setting resembles a hunter looking for rabbits at the top of trees! Cardiovascular physical evaluation, as part of the general physical evaluation consists of observation, palpation, percussion and auscultation. As palpation and percussion have limited diagnostic contribution in the cardiovascular physical evaluation (should not however be omitted), the doctor mainly relies on observation and auscultation. The technique of cardiovascular observation can be easily taught through clinical visits or image-video demonstrations of patients with characteristic phenotypes (genetic syndromes, cyanosis, tachypnea etc). However, to master the most valuable and diagnostically useful “technique”, namely cardiac auscultation, is a challenging task both for students as well as for teachers. Although becoming a master of pediatric cardiac evaluation, capable of approach a specific final diagnosis is rather unrealistic for today’s pediatric trainees and medical students, becoming a self-confident primary health care physician with basic pediatric cardiac auscultation skills allowing for correct referral patterns to pediatric cardiology services is both feasible and greatly appreciated by families and colleagues. Based on our initial experience from pediatric cardiac auscultation teaching courses we documented that the initial clinical performance of participants was suboptimal irrespective of their training level or medical specialty. This is in accordance with the available literature, demonstrating that general pediatricians have 80% sensitivity and 65% specificity in discriminating abnormal from innocent murmurs. In
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Pediatric Cardiac Auscultation. Multimedia-based booklet other words, pediatricians fail to detect 2 out of 10 children with heart disease while inappropriately refer 3-4 children with innocent murmurs. This is not an unexpected finding given the major drawbacks of traditional (bedside) teaching of pediatric cardiac auscultation: a) as it requires consecutive auscultation by student and teacher, there is always doubt whether both teacher and student are listening to the same sound, b) younger children become easily upset, have an increased heart and breathing rate, cannot control their breathing on demand, and are accompanied by their parents distressed by consecutive evaluations of their child by numerous medical students, c) due to the development of pediatric subspecialties, general pediatric trainees will have no chance to evaluate children with congenital heart defects, unless special care is taken, to ensure a minimum time for rotation in pediatric cardiology units as well. For all these reasons, for most medical students and primary health care physicians, the teaching of pediatric cardiology physical evaluation is limited to textbook reading without or very limited “ears on” experience. Multimedia based pediatric cardiology teaching. A cost effective screening for heart disease among school aged children should be based on the clinical skills of primary health care physicians to suspect and correctly refer high risk children for further evaluation. Given the previous drawbacks of “classic” bedside pediatric cardiac auscultation teaching and the limited availability of academically active pediatric cardiologists, the implementation of modern multimedia based teaching approaches represents an attractive and possibly the only available alternative. The modern advances in digital recording of cardiac sounds by using high-tech digital (electronic) stethoscopes, allow for high quality recordings and selective reproduction of pediatric cardiac sounds. By using digital phonocardiography off-line reproduction, concomitant listening by teacher and student becomes feasible for the first time. Furthermore, post processing of initial raw sound signals allows for frequency filtering and selective enhancement of the acoustic properties of abnormal sounds, as well as selective reproduction of the abnormal sounds alone, or in combination with normal sounds. We have documented, in accordance with others, significant improvement of the clinical skills of participants following multimedia based teaching courses. In the present e-book, selected representative digital phonocardiograms, activated during evaluation of “virtual” pediatric cardiology patients, are available, as a substitute of traditional bedside clinical teaching.
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Pediatric Cardiac Auscultation. Multimedia-based booklet The stethoscope Cardiac auscultation, from Hippocrates times up to the beginning of the previous century was performed through direct placement of the doctor’s ear on the patient’s chest wall. Modesty and patient respect was the reasoning that led to the construction of the first stethoscope, which allowed for sound transmission while avoiding the patients’ disturbance due to direct close physical contact with their doctor. From simple single lumen tubes stethoscopes gradually transformed into modern bi-auricular stethoscopes, with diaphragm and bell. Their quality is determined through their ability to proportionally transmit all sound frequencies present in the interface of skin and stethoscope diaphragm or bell, without significant or disproportional losses. Some common principles that all “classic” stethoscopes are subject to are: 1. Human ear can detect a narrow range of sound frequencies (20 Hz-20,000Hz) 2. Diaphragm is appropriate for high frequency sounds detection. 3. Bell, with soft but firm attachment to skin (no pressure!) is appropriate for low frequency sound detection (bass). If pressed against the skin, its acoustic properties are lost and approach those of diaphragm. 4. The smaller the diameter of the contact surface (diaphragm or bell) the higher the filtering out (loss) of lower (bass) frequencies. Pediatric (small interface diameter) stethoscopes therefore preferentially reproduce high frequencies, compared to adult stethoscopes, while neonatal stethoscopes reproduce only the highest frequency sounds with loss of most medium and low frequency sounds. 5. The longer the connecting tubes, the greater the sound intensity loss. 6. An advantage of the small interface diameter of neonatal and pediatric stethoscopes is the precise detection of the localization of the maximum intensity of cardiac sounds on the small dimensioned neonatal or pediatric thorax, respectively, as well as their perfect contact to the skin and resulting elimination of artificial sounds (which is the case when using adult stethoscopes through the partial and variable contact of their interface to the small sized pediatric thorax). 7. The appropriate alignment of the stethoscope tubes to the external ear canal is important, to assure the maximum sound intensity transmission. Modern “electronic” stethoscopes can amplify the intensity of sound transmitted to their interface, thus enhancing detection of low intensity sounds. However, simple intensity amplification doesn’t correspond always to better sound quality, especially if amplification of the whole spectrum of original sound frequencies is not proportional. A
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Pediatric Cardiac Auscultation. Multimedia-based booklet major advantage of electronic (digital) stethoscopes is their connectivity to PCs, providing the potential of digital phonocardiogram storing, for off-line and remote evaluation (telemedical applications). Cardiac auscultation in children is usually performed by the physician’s available stethoscope. General physicians and cardiologists will rather use an adult general or cardiology stethoscope, while pediatricians and neonatologist will prefer pediatric or neonatology stethoscopes. Using an adult stethoscope will improve detection of low frequency sounds at the cost of precise detection of their spatial origin, while using pediatric stethoscopes will result in improved detection only of high frequency sounds. An ideal stethoscope for all purposes doesn’t exist; it is a matter of personal preference. Important is the knowledge of the limitations of each type of stethoscope and preference to the stethoscope that one used for his training in cardiac auscultation. Cardiac sounds A good insight in the mechanical origin of the cardiac sounds, both normal and abnormal, is the basis of a clinically effective cardiac auscultation. All biological sounds are based on motion. Air motion within intestines produces abdominal sounds, within airways wheezing or stridor. Accordingly, heart valve motion, vibrations of the great vessels and blood flow within the heart and vessels all contribute to the genesis of normal and abnormal heart sounds. As the original cardiac sounds are transferred through the thorax to the skin, they are subject to attenuation of their intensity. Additional signal modification takes places as sound is transferred through the stethoscope. Therefore the familiar cardiac sounds we are used to listening through a stethoscope are already “post processed”. However, abnormal attenuation of cardiac sounds resulting in suboptimal diagnostic performance when tissues with different acoustic properties are interposed between heart and stethoscope diaphragm (or bell), such as: 1. Presence of fat (adiposity) 2. Presence of air (emphysema, pneumothorax) 3. Presence of fluid (pericaritis) On the contrary, in cases where the distance of the heart to body surface skin is short, which is the case in most young children, cardiac auscultation is characterized through precise and clear detection not only of normal cardiac sounds, but of further cardiovascular vibrations without any clinical significance (innocent murmurs) which only exceptionally can be detected in adults. Physical properties of sound Each sound is characterized and should be described through its physical properties, including: 1. Intensity of sound corresponds to the easiness of its detection. The commonly used sound intensity scales (decibel) has no practical application in the subjective perception of cardiac sounds by “classic” auscultation. Cardiac auscultatory findings described as murmurs, are commonly classified using a rather subjective 6-step ordinal scale: 1/6 hardly to detect (not everybody agrees that there is a sound), 2/6 low intensity (everybody would agree), 3/6 moderate intensity (no doubt), 4/6 loud associated with thrill (a vibratory sense), 5/6 very loud, 6/6 so loud to be heard even without a stethoscope.
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Pediatric Cardiac Auscultation. Multimedia-based booklet Although this classification is highly subjective, the presence of a thrill easily classifies a sound as of 4/6 or higher intensity. The original intensity of cardiac sounds during their production depends mainly on the magnitude of the force (kinetic energy) which sets into motion the cardiac valves and is responsible for the blood within the heart and vessels. This force is generated through the rhythmic active contraction (systole) of the heart, followed by its passive relaxation to original dimension (diastole). The higher the pressure gradient among two adjacent cavities (vessel, cardiac chamber) the more abrupt the closure of the interposed surface will be (valve), and the louder the resulting sound (as is the case in pulmonary or systemic hypertension, associated with loud pulmonary or aortic valve closure tones). Similarly in the presence of a connection between to cavities (wall defect) or of narrowed valves, the blood flow velocity through the defect or valve will be increased (and the associated sound louder) according to the pressure gradient between the two adjacent cavities. Variable pressure gradient results in variable intensity of cardiac sounds (in cases of total asynchrony between atrial and ventricular contraction- AV block). However, severe cardiovascular malformations might not always produce intense cardiac auscultatory findings, if there is a failure of the cardiac pump to generate the appropriate driving force (heart failure) or the size of the wall defect is so large, resulting into equalization of blood pressure within the adjacent cavities. 2. Baseline frequency, characterizes the sound as low frequency (bass), moderate or high frequency (primo) sound. The baseline frequency is determined through the frequency of the vibration of the surface or of the blood flow which generates the sound. Large area surfaces tend to vibrate at lower frequencies compared to small area surfaces, and produce lower frequency sounds. Comparing the large size of atrioventricular valves with the small size of the arterial valves, it is to be expected that the closure sound of the former will be more bass (of lower frequency) than the later. Similarly, high velocity blood flow tends to generate high frequency murmurs compared to low velocity blood flow. 3. Duration. The exact duration of a cardiac sound (in msec) is impossible to be assessed precisely by auscultation alone. However, of paramount importance is the appropriate distinction whether a cardiac sound is of very short duration or extends more or less in time. Short duration sounds include cardiac sounds (rather inappropriate terminology, as all auscultatory findings are sounds indeed, cardiac tones might be a more appropriate term) and clicks, with sounds having longer duration described as murmurs. In the presence of unexpected additional auscultatory findings, the first initial diagnostic step should always be the comparison of the duration of the unexpected sound with the duration of the normal cardiac sounds: if of comparable duration to them then it should be reported as cardiac sound (tone) or click, if longer as murmur. 4. Temporal variation of sound intensity. For cardiac sounds of prolonged duration (murmurs) the perception of their intensity changes over time (intensity pattern) provides useful additional diagnostic information. Murmurs with increasing intensity are described as crescendo, with decreasing as decrescendo, with initially increasing and then decreasing as crescendo-decrescendo, while those presenting stable intensity throughout their detection as band-shaped. However, in contrast to adult cardiac auscultation where these sound properties are easily appreciated, in pediatric cardiac auscultation, due to
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Pediatric Cardiac Auscultation. Multimedia-based booklet increased heart rate, the duration of most murmurs is usually too short to allow for a precise description of the temporal variation of sound intensity. Further specific properties of cardiac sounds: 5. Timing within the cardiac cycle: the correct classification of cardiac sounds according to the cardiac cycle phase (systole, diastole) is of paramount diagnostic importance. Cardiac sounds therefore can be systolic, diastolic or continuous (present in systole and diastole without a pause). 6. Localization on thorax. Cardiac sounds should be described according to a) the location where the sound is heard at its maximum intensity (punctum maximum-p.m), a description of paramount clinical importance b) the area of transmission, the locations where the sound is also heard (with lower though intensity compared to p.m). The “classic� cardiac auscultation areas are the heart apex, corresponding to the point where the apical impulse is detected (normally along the left midclavicular line, lateral to the nipple), lower left parasternal area (4th intercostal space left / 4LICS), left and right upper parasternal area (2nd intercostal space left and right / 2LICS and 2RICS). However, pediatric cardiac auscultation should include a thorough evaluation of the whole precordial area, as well as of subclavian areas, fossa jugularis, both axillae and posterior thorax as well. 8. Detailed description of all acoustic phenomena within a given cardiac cycle. This is a difficult task, as human senses tend to concentrate on the most impressive, intense or prominent characteristic of a given stimulus. However, often the secondary or non impressive determinants of an auditory stimulus in cardiac auscultation contain clinically important information. Detection of murmurs is not difficult for an inexperienced physician, their description in terms of localization and timing within cardiac cycle is more difficult, even more the description of their frequency and intensity temporal variation. But the detection of additional acoustic phenomena as clicks, wide and fixed split of the second heart tone, and detection of the diastolic component of a continuous murmur or the presence of a discrete diastolic murmur requires a systemic and careful approach in cardiac auscultation. 9. Final decision making-clinical significance. Following the detailed description of auscultatory findings, a physician must be able to clearly state whether the cardiac auscultatory findings were those expected and suggestive of a normal cardiac function and anatomy, or unexpected and highly suggestive of an abnormal state? The important issue in other words is whether the child needs further referral to pediatric cardiology services or not, based on cardiac auscultatory findings. Heart mechanical function A simplified presentation of the anatomy and mechanical function of the heart is very useful for understanding the genesis of the expected (normal) and unexpected (abnormal) cardiac auscultatory findings. We can imagine the heart as a pump connected to a closed circuit system of tubes (arteries-capilaries-veins), within which the cardiac valves act as valves ensuring one way (monodromic) blood flow within the closed system. Although we commonly refer to a single circulatory system, one must remember that this is divided into two components, with one pump for the systemic circulation (left ventricle) and one for the pulmonary circulation (right ventricle), connected in series.
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Pediatric Cardiac Auscultation. Multimedia-based booklet Cardiac valves can ensure through their perfect closure one way blood flow. They are classified into two groups: a) inlet atrioventricular valves (AV-valves, mitral and tricuspid for left and right ventricle, respectively) and b) outlet arterial valves (art. valves, aortic and pulmonary valve, for LV and RV respectively). AV valves and arterial valves are placed in the inlet and outlet part of the ventricles in such a spatial relationship that passive closing of the former when the latter open (in systole) and vice versa (in diastole) is ensured. Their passive opening and closure depends on the pressure gradient of adjacent (proximal and distal) cardiac chambers while their perfect closure against a pressure gradient is maintained through either a specific supportive system, the papillary muscles and chordae tendinae for the AV valves or the appropriately shaped (semilunar) arterial valve leaflets. The anatomic division of the heart into two separate and in series connected pumps is achieved through the development in early fetal life of an interatrial and interventricular septum, dividing the common atrial and ventricular cavities into separate chambers designated for the right (pulmonary) and left (systemic) circulation. The common single output vessel, the truncus arteriosus, divides itself similarly into two vessels (aorta and pulmonary artery) while the inlet vessels (veins) differentiate into right (vena cavae) and left (pulmonary) veins which connect to the corresponding atrium. This complex embryologic process results into the development of two separate pump systems, each having its own connections with inlet and outlet vessels, collecting chamber (atrium), contracting chamber (ventricle) and inlet (AV) and outlet (art) valves. Although fetal circulation is characterized by the parallel connection of the two circulations, the closure of the fetal intra and extra-cardiac communications soon after birth, results into two complete separate circulations, connected in series.
Cardiac cycle phases A cardiac cycle is divided into to major phases: a) the contraction (systole) of the cardiac muscle resulting in closure of AV valves, opening of the arterial valves and pumping of blood into the great arteries and b) the relaxation (diastole) of the cardiac muscle resulting in closure of the arterial valves, opening of the AV valves and filling of the intracardiac chambers. Always remembering the movement of the valves during each phase is very important in providing a correct differential diagnosis based on cardiac auscultation. (d1,2,3) More specifically:
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Pediatric Cardiac Auscultation. Multimedia-based booklet Systole. Following the contraction (systole) of the cardiac muscle and the rise of intraventricular pressure, the AV valves close first (at the point the intraventricular pressure will exceed that of intraatrial pressure) and soon afterwards the arterial valves open (when the intraventricular pressure will exceed the arterial pressure). (d1,2,3) The time interval between AV valve closure and arterial valve opening is called isovolumic contraction, as active contraction of the ventricles is not accompanied by any reduction of intraventricular volume despite the rapidly rising intraventricular pressures. Systole is therefore serially characterized through the following mechanical events: 1. closure of the atrioventricular valves, followed by 2. opening of the arterial valves, followed by 3. ejection of blood to the pulmonary and systemic circulation Diastole. It represents the expansion (diastole) of the ventricle to its initial dimension. This expansion is associated with rapid reduction of intraventricular pressure, resulting in closure of arterial valves, opening of the atrioventricular valves soon afterwards and filling of the ventricle. (d1,2,3) Closure of the arterial valves is the first event in diastole, and occurs at the point when the intraventricular pressure becomes lower than the arterial pressure. When the intraventricular pressure becomes lower than the atrial pressure the atrioventricular valves will open, allowing for ventricular filling with blood collected in the atria during systole. The time interval between arterial valve closure and AV valve opening is called isovolumic relaxation, as the rapid decline of intraventricular pressure is not associated with any increase of intraventricular volume. Following AV valve opening, ventricular filling is initially passive, driven through the pressure gradient between atrium and ventricle (early-passive filling). This allows for most of the blood collected during systole in the atria (due to the descend of the AV annulus towards the apex of the heart in systole) to flow within the ventricles. Later in diastole atrial contraction will result in more blood flowing from atria to ventricles (active-late filling). Diastole therefore is serially characterized through the following mechanical events: 1. closure of arterial valves 2. opening of atrioventricular valves 3. passive ventricular filling 4. active ventricular filling (atrial systole)
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Pediatric Cardiac Auscultation (multimedia-based booklet)
I. Germanakis “Cardiac auscultation: a glorious past! But does it have a future?” This publication title, presented in an esteemed cardiology journal more than a decade ago, depicts nicely the continuing controversy regarding the usefulness of cardiac auscultation, one of the oldest physical evaluation practices, in the era of modern cardiology. Instead of providing numerous arguments in favor of a long lasting role of “classic” medical practices, including cardiac auscultation, we preferred to use modern technological advances in sound recording to offer a modern approach in “traditional” pediatric cardiac auscultation teaching. The basic principles of normal and abnormal cardiac sound physics are briefly presented in the e-book, with numerous links to both graphic displays and sound files. Common clinical problems in pediatric cardiac auscultation are presented in each chapter; the importance of a complete physical evaluation and history taking is also emphasized. The multimedia consists of “virtual” cases, linked to digital recordings obtained from real pediatric cardiology patients. Post processing of original recordings, through frequency and time filtering, emphasize the abnormal auscultatory findings. Based on the belief that only those who master a technique can appreciate its potential impact and the knowledge that early detection of heart disease in neonates and children is life saving, we hope this e-book represents a helpful introduction to the fascinating world of pediatric cardiac auscultation for both medical students and physicians caring for children!