Automatic pediatric congenital heart disease classification based on heart sound signal.

Congenital heart diseases (CHD) are the most common birth defects, and the early diagnosis of CHD is crucial for CHD therapy. However, there are relatively few studies on intelligent auscultation for pediatric CHD, due to the fact that effective cooperation of the patient is required for the acquisition of useable heart sounds by electronic stethoscopes, yet the quality of heart sounds in pediatric is poor compared to adults due to the factors such as crying and breath sounds. This paper presents a novel pediatric CHD intelligent auscultation method based on electronic stethoscope. Firstly, a pediatric CHD heart sound database with a total of 941 PCG signal is established. Then a segment-based heart sound segmentation algorithm is proposed, which is based on PCG segment to achieve the segmentation of cardiac cycles, and therefore can reduce the influence of local noise to the global. Finally, the accurate classification of CHD is achieved using a majority voting classifier with Random Forest and Adaboost classifier based on 84 features containing time domain and frequency domain. Experimental results show that the performance of the proposed method is competitive, and the accuracy, sensitivity, specificity and f1-score of classification for CHD are 0.953, 0.946, 0.961 and 0.953 respectively.

Should the ultrasound probe replace your stethoscope? A SICS-I sub-study comparing lung ultrasound and pulmonary auscultation in the critically ill.

BACKGROUND: In critically ill patients, auscultation might be challenging as dorsal lung fields are difficult to reach in supine-positioned patients, and the environment is often noisy. In recent years, clinicians have started to consider lung ultrasound as a useful diagnostic tool for a variety of pulmonary pathologies, including pulmonary edema. The aim of this study was to compare lung ultrasound and pulmonary auscultation for detecting pulmonary edema in critically ill patients. METHODS: This study was a planned sub-study of the Simple Intensive Care Studies-I, a single-center, prospective observational study. All acutely admitted patients who were 18 years and older with an expected ICU stay of at least 24 h were eligible for inclusion. All patients underwent clinical examination combined with lung ultrasound, conducted by researchers not involved in patient care. Clinical examination included auscultation of the bilateral regions for crepitations and rhonchi. Lung ultrasound was conducted according to the Bedside Lung Ultrasound in Emergency protocol. Pulmonary edema was defined as three or more B lines in at least two (bilateral) scan sites. An agreement was described by using the Cohen κ coefficient, sensitivity, specificity, negative predictive value, positive predictive value, and overall accuracy. Subgroup analysis were performed in patients who were not mechanically ventilated. RESULTS: The Simple Intensive Care Studies-I cohort included 1075 patients, of whom 926 (86%) were eligible for inclusion in this analysis. Three hundred seven of the 926 patients (33%) fulfilled the criteria for pulmonary edema on lung ultrasound. In 156 (51%) of these patients, auscultation was normal. A total of 302 patients (32%) had audible crepitations or rhonchi upon auscultation. From 130 patients with crepitations, 86 patients (66%) had pulmonary edema on lung ultrasound, and from 209 patients with rhonchi, 96 patients (46%) had pulmonary edema on lung ultrasound. The agreement between auscultation findings and lung ultrasound diagnosis was poor (κ statistic 0.25). Subgroup analysis showed that the diagnostic accuracy of auscultation was better in non-ventilated than in ventilated patients. CONCLUSION: The agreement between lung ultrasound and auscultation is poor. TRIAL REGISTRATION: NCT02912624. Registered on September 23, 2016.

Practical "pearls" to help improve your care.

This month's review of the current uses of ultrasound in family medicine made me wonder whether ultrasound might become the stethoscope of the future.

Utilidad de la ecografía portátil en el cribado del aneurisma de aorta abdominal y de la ateromatosis de aorta abdominal / Feasibility of hand-held-ultrasonography in the screening of abdominal aortic aneurysms and abdominal aortic atherosclerosis

Fundamento y objetivo: La diabetes mellitus tipo 2 (DM2) se asocia con un elevado riesgo cardiovascular (RCV), siendo de gran importancia tratar intensivamente los distintos factores de RCV, como la dislipemia. El tratamiento hipocolesterolemiante es necesario para conseguir reducir el RCV asociado a la DM2, siendo el colesterol unido a lipoproteínas de baja densidad (colesterol LDL) el principal objetivo terapéutico. En este trabajo se analiza el perfil lipídico de pacientes diabéticos en tratamiento con estatinas. Pacientes y método: El estudio DYSIS (Dyslipidemia International Study) es un estudio observacional, internacional, en el que se analiza el perfil lipídico de pacientes tratados con estatinas, en prevención primaria o secundaria. Resultados: De los 3703 pacientes analizados, el 39% eran diabéticos. El 59,2% de los diabéticos presentaban el colesterol LDL fuera de control. En conjunto, el 43,6% de diabéticos presentaba triglicéridos elevados y el 36,4% tenían el colesterol unido a lipoproteínas de alta densidad (colesterol HDL) bajo. De los pacientes con cardiopatía isquémica y diabetes, el 31% tenían colesterol LDL, colesterol HDL y triglicéridos fuera de control. De los pacientes diabéticos con síndrome metabólico el 60% tiene el colesterol LDL fuera de objetivos, el 39,8% tienen el colesterol HDL bajo y el 46,6% triglicéridos elevados. El 57% de los pacientes diabéticos obesos presentaba falta de control del colesterol LDL, aún en tratamiento con estatinas. Conclusiones: Las enfermedades cardiovasculares son la primera causa de morbimortalidad en pacientes con DM2. El estudio DYSIS muestra que la mayoría de los pacientes tratados con estatinas no alcanzan los objetivos lipídicos recomendados por las guías. En el presente estudio se constata que más de la mitad de los diabéticos tratados con estatinas tiene el colesterol LDL fuera de control, el grado de control de la dislipemia es muy limitado a pesar del tratamiento con estatinas, lo que puede determinar la necesidad de una terapia combinada para el tratamiento eficaz de la dislipemia (AU)

Background and objective: To determine the prevalence of abdominal aortic aneurysm (AAA) and abdominal aortic atheromatosis (AA-At) using a hand-held ultrasound by a general practitioner in the public Primary Health Care system. Patients and method: Pilot study that prospectively studied a cohort of men over 50 years with cardiovascular risk factors: active smokers, former smokers, or hypertensive patients, attended in primary health care center. The general practitioner completed an ultrasonography training in an Ultrasound Unit under supervision of experienced radiologists using an standard ultrasound equipment and hand-held ultrasound (VScan1, General Electric, USA). One hundred and six patients participated in the study and all imaging data recorded were blindly evaluated by a radiologist in order to establish the concordance in the interpretation of images between general practitioner and radiologist. The kappa index was calculated to study the agreement on the presence or absence of AAA and AA-At. Results: We observed a prevalence of 5.88% of AAA. Kappa index for concordance in AAA diagnosis was absolute (k = 1.0), with a sensitivity and specificity of 100%. Otherwise, the general practitioner identified 59 patients (58.4%) with AA-At, while radiologist identified 39 (38.6%) in the image review, with moderate concordance (k = .435), sensitivity 89.74% and specificity 57.14%. Hypercholesterolemia (odds ratio [OR] 2.61; 95% confidence interval [95% CI] 0.92-7.39) and diabetes mellitus (OR 3.35; 95%CI 0.89-12.55) were independent risk factors for AA-At development in logistic regression. Conclusions: After an adequate training in ultrasonography, hand-held ultrasound is a useful tool for AAA screening in Primary Care. Its simplicity, security, validity, cost-effectiveness and acceptance by the general population, makes it a feasible tool for cardiovascular risk assessment (AU)

In defense of the stethoscope.

The stethoscope is widely considered to be an unreliable instrument. Many studies document the significant observer variability in its use. Numerous other diagnostic tools are available that are generally regarded to provide more reliable diagnostic information. Some even argue that teaching of the ancient art should be de-emphasized in medical schools. Yet auscultation with an acoustic stethoscope can provide important, even life-saving, information. The purpose of this article is to present evidence that supports the use of the stethoscope in clinical medicine. The argument for the stethoscope will be made by presenting relevant investigations, including clinical studies acknowledged to meet the criteria of evidence-based medicine. It will focus on studies that have employed computerized acoustic technology to correlate lung sounds with disease states. This technology has advanced in recent years, which has stimulated a resurgence of interest in auscultation. Numerous studies have been done that utilized objective methods that circumvented the problem of observer variability. There is now a good deal of scientific evidence to support the hypothesis that lung sounds contain information that is clinically useful. This technology also allows this information to be collected more efficiently than previously possible. Advances in educational technology have made it possible to impart information on auscultation much more easily than was possible in the past. Contrary to predictions, the stethoscope is not likely to be relegated to the museum shelf in the near future. Computer technology is making it an even more useful clinical instrument.

Cardiac auscultation: a glorious past--and it does have a future!

Cardiac auscultation remains an important part of clinical medicine. The standard acoustic stethoscope, which has been useful for more than a century, cannot process, store, and play back sounds or provide visual display, and teaching is hindered because there is no means to distribute the same sounds simultaneously to more than one listener. Modern portable and inexpensive tools are now available to provide, through digital electronic means, better sound quality with visual display and the ability to replay sounds of interest at either full or half speed with no loss of frequency representation or sound quality. Visual display is possible in both standard waveform and spectral formats. The latter format is readily available and provides certain advantages over the time-honored waveform (phonocardiographic) method. Both methods, however, can and should be used simultaneously. Sound signals obtained electronically may then be subjected to objective visual and numerical analysis, transmitted to distant sites, and stored in medical records. Signal analysis shows early promise for clinical application, such as in the assessment of severity of aortic stenosis and in the separation of innocent from organic murmurs. In addition to their clinical value, these methods provide a critical vehicle for the teaching of cardiac auscultation, a method that can and should be preserved for future generations.

Flora bacteriana de las olivas de los estetoscopios / Bacterial flora of olives of the stethoscopies

La bacteria que se aísla con mayor frecuencia de las olivas de los estetoscopios es Staphylococcus epidermidis.Esta bacteria puede estar implicada en brotes de infección nosocomial. La limpieza y desinfección de los estetoscopios, incluyendo tanto la membrana como de las olivas, debe incluirse en los protocolos de prevención de la infección nosocomial (AU)