[Cardiac auscultation in children]. / L'auscultazione cardiaca nel bambino.

Cardiac auscultation permits to distinguish between the innocent heart murmurs and pathologic murmurs; characteristics of pathologic murmurs include a holosystolic or diastolic murmur, maximal murmur intensity at the upper left sternal border and increased intensity when the patient stands. Murmurs should be described by their timing in the cardiac cycle, intensity, shape, pitch, location, radiation, and response to dynamic maneuvers. When the medical history and physical examination support the diagnosis of innocent heart murmur, neither further investigation nor referal is indicated. On the contrary, echocardiography is recommended for patients with any other abnormal physical examination findings that increase the likelihood of structural heart disease. In this review we discuss the definition and classification of murmurs, how to evaluate it.

A system for heart sounds classification.

The future of quick and efficient disease diagnosis lays in the development of reliable non-invasive methods. As for the cardiac diseases - one of the major causes of death around the globe - a concept of an electronic stethoscope equipped with an automatic heart tone identification system appears to be the best solution. Thanks to the advancement in technology, the quality of phonocardiography signals is no longer an issue. However, appropriate algorithms for auto-diagnosis systems of heart diseases that could be capable of distinguishing most of known pathological states have not been yet developed. The main issue is non-stationary character of phonocardiography signals as well as a wide range of distinguishable pathological heart sounds. In this paper a new heart sound classification technique, which might find use in medical diagnostic systems, is presented. It is shown that by combining Linear Predictive Coding coefficients, used for future extraction, with a classifier built upon combining Support Vector Machine and Modified Cuckoo Search algorithm, an improvement in performance of the diagnostic system, in terms of accuracy, complexity and range of distinguishable heart sounds, can be made. The developed system achieved accuracy above 93% for all considered cases including simultaneous identification of twelve different heart sound classes. The respective system is compared with four different major classification methods, proving its reliability.

Automatic heart sounds detection and systolic murmur characterization using wavelet transform and AR modeling.

This paper describes a signal processing procedure that identifies the first and the second heart sounds (S1 and S2), extracts the systole from the diastole, detects and characterizes the systolic murmur found within. The identification of heart sounds was facilitated by discrete wavelet transform (DWT) approximation using the Coiflet wavelet and followed by using indicators that quantify signal activity and strength. The systole was isolated and divided into smaller short segments where the signal activity measure and absolute amplitude were computed. S1 and S2, and the onset and duration of a systolic murmur were marked. Using the indices derived from AR modeling, a systolic murmur can be characterized by its timing, duration, pitch, and shape either as crescendo, decrescendo, crescendo-decrescendo, or plateau. The performance of the proposed procedure was evaluated and proved with clinically recorded systolic murmur episodes.

Casos clínicos en Cardiología (Nº 11): lactante de tres meses que se fatiga con las tomas / Clinical cases in Cardiology (nº 11): three months old infant showing shortness of breath when feeding

Continuamos con la serie de casos clínicos en Cardiología pediátrica, revisando los motivos de consulta y datos exploratorios frecuentes en las consultas de Pediatría de Atención Primaria, y presentados de forma breve y práctica. En este número se presenta el caso de un lactante de tres meses que acude por fatiga y sudoración con las tomas. Se discute cómo la exploración y los hallazgos electrocardiográficos orientan el manejo diagnóstico de este paciente (AU)

We continue the series of clinical cases in Pediatric Cardiology checking frequent reasons for consultation in the pediatric offices of Primary Care as well as exploratory signs, and presenting them in a brief and practical way. In this paper, we present the case of a 3 month-old infant who is taken because of shortness of breath and sweating with feeding. The way the physical exploration and the electrocardiographic findings guide the diagnosis of this patient is discussed (AU)

On systolic murmurs and cardiovascular physiological maneuvers.

Physiological principles that directly apply to physical diagnosis provide opportune occasions to bring basic science to the bedside. In this article, we describe the effect of cardiac maneuvers on systolic murmurs and how physiological principles apply to the explanation of the changes noted at the bedside. We discuss the effect of Valsalva, squatting, and hand grip maneuvers on different physiological parameters influencing preload, afterload, chamber dimensions, and pressure gradients. The clinical manifestations noted during the aforementioned maneuvers are described in common cardiac conditions responsible for the production of certain systolic murmurs.

Comunicación intraventicular en un paciente adulto / Ventricular septal defect in an adult patient

Presentamos el caso clínico de un varón asintomático de 46 años en cuya radiografía de tórax se observa un botón aórtico derecho y en la exploración física un soplo sistólico con frémito palpable paraesternal izquierdo. Al realizársele ecocardiografía transesofágica y RMN se encontró una comunicación interventricular (CIV) que únicamente precisa revisiones ecocardiográficas periódicas. La CIV es la cardiopatía congénita más frecuente. Las CIV pueden ser membranosas, de entrada, trabeculadas o infundibulares. La sintomatología puede ser desde anodina únicamente con un soplo pansistólico paraesternal izquierdo en la exploración física, hasta hiperaflujo pulmonar que llegue a causar insuficiencia cardiaca. La radiografía de tórax mostrará cardiomegalia, el electrocardiograma hipertrofia biventricular y la ecocardiografía y la resonancia magnética mostrarán tamaño y número de comunicaciones. El tratamiento es conservador, ya que el 50% se cierran de forma espontánea en los primeros años de vida, reservando la cirugía para los casos sintomáticos y los asintomáticos con cortocircuito significativo (AU)

We report the case of a 46 year old asymptomatic male whose chest X-ray showed a right aortic knob and in the physical examination he had a systolic murmur with a palpable left parasternal heave. On performing the transesophageal echocardiography and MRI a ventricular septal defect (VSD) was observed which only requires periodic echocardiographic reviews. VSD is the most common congenital heart disease. The VSD may be membranous, inlet, trabecular, or infundibular. The clinical signs may range from only anodyne with a left pansystolic parasternal murmur on physical examination, up to lung hyper-flow which may lead to heart failure. The chest X-ray showed cardiomegaly, the electrocardiogram showed biventricular hypertrophy, and the echocardiography and MRI showed the size and number of communications. Treatment is conservative, since 50% close spontaneously in the first years of life, reserving surgery for symptomatic and asymptomatic cases with a significant shunt (AU)

Matrix decomposition based feature extraction for murmur classification.

Heart murmurs often indicate heart valvular disorders. However, not all heart murmurs are organic. For example, musical murmurs detected in children are mostly innocent. Because of the challenges of mastering auscultation skills and reducing healthcare expenses, this study aims to discover new features for distinguishing innocent murmurs from organic murmurs, with the ultimate objective of designing an intelligent diagnostic system that could be used at home. Phonocardiographic signals that were recorded in an auscultation training CD were used for analysis. Instead of the discrete wavelet transform that has been used often in previous work, a continuous wavelet transform was applied on the heart sound data. The matrix that was derived from the continuous wavelet transform was then processed via singular value decomposition and QR decomposition, for feature extraction. Shannon entropy and the Gini index were adopted to generate features. To reduce the number of features that were extracted, the feature selection algorithm of sequential forward floating selection (SFFS) was utilized to select the most significant features, with the selection criterion being the maximization of the average accuracy from a 10-fold cross-validation of a classification algorithm called classification and regression trees (CART). An average sensitivity of 94%, a specificity of 83%, and a classification accuracy of 90% were achieved. These favorable results substantiate the effectiveness of the feature extraction methods based on the proposed matrix decomposition method.

Modeling of heart systolic murmurs based on multivariate matching pursuit for diagnosis of valvular disorders.

Heart murmurs are pathological sounds produced by turbulent blood flow due to certain cardiac defects such as valves disorders. Detection of murmurs via auscultation is a task that depends on the proficiency of physician. There are many cases in which the accuracy of detection is questionable. The purpose of this study is development of a new mathematical model of systolic murmurs to extract their crucial features for identifying the heart diseases. A high resolution algorithm, multivariate matching pursuit, was used to model the murmurs by decomposing them into a series of parametric time-frequency atoms. Then, a novel model-based feature extraction method which uses the model parameters was performed to identify the cardiac sound signals. The proposed framework was applied to a database of 70 heart sound signals containing 35 normal and 35 abnormal samples. We achieved 92.5% accuracy in distinguishing subjects with valvular diseases using a MLP classifier, as compared to the matching pursuit-based features with an accuracy of 77.5%.

The pulmonary valve.

The pulmonary valve consists of 3 leaflets and is similar in anatomy to the aortic valve. It is the least likely to be affected by acquired disease, and thus, most disorders affecting it are congenital. The most common hemodynamic abnormality of the pulmonary valve is the congenitally narrowed domed valve of pulmonic stenosis. Pulmonary stenosis is usually well tolerated in its mild and moderate forms. This article discusses the clinical evaluation, cardiac catheterization, and echocardiography of pulmonary stenosis and pulmonary regurgitation.

Etiology and diagnosis of systolic murmurs in adults.

BACKGROUND: It is unknown whether echocardiography can provide insights into the origin of systolic murmurs and the modern value of bedside cardiovascular diagnosis. METHODS: The author examined 376 inpatients and compared their physical findings to transthoracic echocardiography, exploring the associations between echocardiography and systolic murmurs and investigating the diagnostic accuracy of physical examination for pathologic murmurs. RESULTS: Four echocardiographic variables predict the presence of systolic murmurs: peak aortic velocity (P <.001); mitral regurgitation severity (P <.001); mitral valve E-point velocity (P=.09); and absence of pericardial effusion (P=.09). When diagnosing murmurs, the most helpful finding is its distribution on the chest wall with respect to the 3(rd) left parasternal space, a landmark that distinguishes murmurs into 6 patterns. The "apical-base" pattern indicates increased aortic velocity (likelihood ratio [LR] 9.7; 95% confidence interval [CI]; 6.7-14): a delayed carotid upstroke (LR 6.8; 95% CI; 4.0-11.5); absent S2 (LR 12.7; 95% CI; 5.3-30.4); and humming quality to the murmur (LR 8.5; 95% CI; 4.3-16.5) further increase the probability of aortic valve disease. The "broad apical" murmur pattern suggests significant mitral regurgitation (LR 6.8; 95% CI; 3.9-11.9); and the "left lower sternal" murmur pattern indicates significant tricuspid regurgitation (LR 8.4; 95% CI; 3.5-20.3): additional bedside observations refine these diagnoses. Nonetheless, this study shows that some classic physical findings are no longer accurate, that physical examination cannot reliably distinguish severe aortic stenosis from less severe stenosis, and that classic physical findings, despite having proven value, are absent in many patients with significant cardiac lesions. CONCLUSIONS: In the diagnosis of systolic murmurs, physical examination has limitations but also unappreciated value. A simple system using onomatopoeia and classifying systolic murmurs into 1 of 6 patterns is diagnostically helpful.

Varón de edad avanzada con soplo sistólico. Propuesta de un esquema de diagnóstico diferencial / Elderly male with systolic murmur. A proposal of a differential diagnosis schema

La presencia de un soplo sistólico a la auscultación cardiaca es un hallazgo frecuente en los pacientes de edad avanzada. El origen de estos soplos, puede ser debido a causas banales sin trascendencia clínica ni pronóstica o pueden ser provocados por patologías graves que requieren tratamiento específico. La prueba de elección para el estudio de un soplo es, en la actualidad, la ecocardiografía döppler. Sin embargo, la auscultación minuciosa junto con la realización de determinadas maniobras auscultatorias y el estudio del pulso carotideo son técnicas fundamentales en la consulta del médico de familia que nos permiten aproximarnos al diagnóstico y seleccionar a los pacientes para la realización de un estudio ecocardiográfico (AU)

The presence of a systolic murmur on cardiac auscultation is a frequent finding in the elderly patient. The origin of these murmurs may be due to insignificant causes without clinical or prognostic importance or may be caused by serious conditions that require specific treatment. The test of choice to study a murmur is currently the Doppler echocardiography. However, careful auscultation together with the performance of some auscultation maneuvers and the study of the carotid pulse are fundamental techniques in the family medical consultation that allow us to approach the diagnosis and select the patient who need an echocardiography study AU)

Casos clínicos en Cardiología (nº 3): niño de 7 años con un soplo sistólico / No disponible

Continuamos con la serie de casos clínicos en Cardiología pediátrica revisando los motivosde consulta y datos exploratorios frecuentes en las consultas de Pediatría de Atención Primaria,y presentados de forma breve y práctica. En este número se presenta el caso de un niñode 7 años al que se le detecta un soplo sistólico en el contexto de una infección respiratoria vírica.Se discute cómo la exploración y los hallazgos electrocardiográficos orientan el manejodiagnóstico de este paciente(AU)

We continue the series of clinical cases in Pediatric Cardiology checking frequent reasonsfor consultation in the pediatric offices of Primary Care as well as exploratory signs, and presentingthem in a brief and practical way. In this paper we present the case of a 7 years old boyto whom a systolic murmur is noticed in the context of a viral respiratory infection. The waythe physical exploration and the electrocardiographic findings guide the diagnosis of this patientis discussed(AU)

Resolution of a giant atrial thrombus following anticoagulation therapy.

We report on a patient in whom a giant thrombus in the left atrium was detected by transthoracic echocardiography. Anticoagulant theraphy was started. After two months of therapy, repeat echocardiography showed complete resolution of the thrombus. This case indicates that large and presumably organised thrombi may be treated with anticoagulant therapy.

A simplicity-based fuzzy clustering approach for detection and extraction of murmurs from the phonocardiogram.

Almost all cardiac abnormalities manifest themselves as murmurs in a phonocardiogram (PCG). The location of a murmur in the PCG over a cardiac cycle depends on the underlying cardiac abnormality. Locating murmurs with respect to the cardiac cycle is useful for diagnosing cardiac dysfunction. Locating murmurs is difficult due to spectral similarity and time overlap with other heart sounds. Moreover, the wide variation in murmur amplitudes and murmur spectral characteristics across different patients and abnormalities has hindered the design of a generic time segmentation algorithm to isolate murmurs within the PCG. In this paper, we present a method to locate cardiac murmurs within the PCG that is based on their visual simplicity, which does not depend upon their absolute amplitude and frequency characteristics, and hence, results in their better localization. Then, we identify fuzzy sets to cluster simplicity values, due to murmurs, to determine the time duration over which the murmur occurs. The overall accuracy of the proposed algorithm in detecting systolic murmurs is 80%. The sensitivity of the algorithm in locating systolic murmurs is 73% and its specificity is 100%. The isolated murmur can then be further processed to extract clinically relevant features to diagnose the nature of the cardiac abnormality. Experimental results with a variety of murmurs are provided.

Computerized heart sounds analysis.

This paper is concerned with a synthesis study of the fast Fourier transform (FFT), the short-time Fourier transform (STFT), the Wigner distribution (WD) and the wavelet transform (WT) in analysing the phonocardiogram signal (PCG). It is shown that these transforms provide enough features of the PCG signals that will help clinics to obtain qualitative and quantitative measurements of the time-frequency (TF) PCG signal characteristics and consequently aid diagnosis. Similarly, it is shown that the frequency content of such a signal can be determined by the FFT without difficulties. The studied techniques (FT, STFT, WD, CWT, DWT and PWT) of analysis can thus be regarded as complementary in the TF analysis of the PCG signal; each will relate to a part distinct from the analysis in question.