Voice reduction in cardiac auscultation sounds with reference signals measured from vocal resonators.

This study proposes the use of vocal resonators to enhance cardiac auscultation signals and evaluates their performance for voice-noise suppression. Data were collected using two electronic stethoscopes while each study subject was talking. One collected auscultation signal from the chest while the other collected voice signals from one of the three voice resonators (cheek, back of the neck, and shoulder). The spectral subtraction method was applied to the signals. Both objective and subjective metrics were used to evaluate the quality of enhanced signals and to investigate the most effective vocal resonator for noise suppression. Our preliminary findings showed a significant improvement after enhancement and demonstrated the efficacy of vocal resonators. A listening survey was conducted with thirteen physicians to evaluate the quality of enhanced signals, and they have received significantly better scores regarding the sound quality than their original signals. The shoulder resonator group demonstrated significantly better sound quality than the cheek group when reducing voice sound in cardiac auscultation signals. The suggested method has the potential to be used for the development of an electronic stethoscope with a robust noise removal function. Significant clinical benefits are expected from the expedited preliminary diagnostic procedure.

Real-world evaluation of the Stemoscope electronic tele-auscultation system.

BACKGROUND: With the spread of COVID-19, telemedicine has played an important role, but tele-auscultation is still unavailable in most countries. This study introduces and tests a tele-auscultation system (Stemoscope) and compares the concordance of the Stemoscope with the traditional stethoscope in the evaluation of heart murmurs. METHODS: A total of 57 patients with murmurs were recruited, and echocardiographs were performed. Three cardiologists were asked to correctly categorize heart sounds (both systolic murmur and diastolic murmur) as normal vs. abnormal with both the Stemoscope and a traditional acoustic stethoscope under different conditions. Firstly, we compared the in-person auscultation agreement between Stemoscope and the conventional acoustic stethoscope. Secondly, we compared tele-auscultation (recorded heart sounds) agreement between Stemoscope and acoustic results. Thirdly, we compared both the Stemoscope tele-auscultation results and traditional acoustic stethoscope in-person auscultation results with echocardiography. Finally, ten other cardiologists were asked to complete a qualitative questionnaire to assess their experience using the Stemoscope. RESULTS: For murmurs detection, the in-person auscultation agreement between Stemoscope and the acoustic stethoscope was 91% (p = 0.67). The agreement between Stemoscope tele-auscultation and the acoustic stethoscope in-person auscultation was 90% (p = 0.32). When using the echocardiographic findings as the reference, the agreement between Stemoscope (tele-auscultation) and the acoustic stethoscope (in-person auscultation) was 89% vs. 86% (p = 1.00). The system evaluated by ten cardiologists is considered easy to use, and most of them would consider using it in a telemedical setting. CONCLUSION: In-person auscultation and tele-auscultation by the Stemoscope are in good agreement with manual acoustic auscultation. The Stemoscope is a helpful heart murmur screening tool at a distance and can be used in telemedicine.

Murmurs other than the early diastolic murmur in aortic dissection.

The purpose of this review is to draw attention to the presence and significance of murmurs other than the murmur of aortic regurgitation, in patients with aortic dissection. For that purpose, a literature search was conducted using Pubmed and Googlescholar. The search terms were "dissecting aneurysm of the aorta", "systolic murmurs", "ejection systolic murmurs", "holosystolic" murmurs, "continuous murmurs", and "Austin-Flint" murmur. Murmurs other than the murmur of aortic regurgitation, which were associated with aortic dissection, fell into the categories of systolic murmurs, some of which were holosystolic, and continuous murmurs, the latter attributable to fistulae between the dissecting aneurysm and the left atrium, right atrium, and the pulmonary artery, respectively. Mid-diastolic murmurs were also identified, and these typically occurred in association with both the systolic and the early diastolic murmurs. Among patients with systolic murmurs clinical features which enhanced the pre-test probability of aortic dissection included back pain, stroke, paraplegia, unilateral absence of pulses, interarm differences in blood pressure, hypertension, shock, bicuspid aortic valve, aortic coarctation, Turner's syndrome, and high D-dimer levels, respectively. In the absence of the murmur of aortic regurgitation timely diagnosis of aortic dissection could be expedited by increased attention to parameters which enhance pretest probability of aortic dissection. That logic would apply even if the only murmurs which were elicited were systolic murmurs.

Maternity Providers' Perspectives on Barriers to Utilization of Intermittent Fetal Monitoring: A Qualitative Study.

There are 2 approaches to fetal assessment during labor: continuous electronic fetal monitoring (EFM) and intermittent auscultation (IA). The vast majority of healthy labors in the United States use EFM, despite professional organization recommendations against its use for low-risk pregnancies. This qualitative investigation explores maternity care team members' perspectives on why EFM is the dominant approach to fetal assessment instead of IA. Focus groups comprised of nurses, midwives, and physicians were conducted using a semistructured interview guide. Transcripts were analyzed using directed content analysis to identify themes related to clinical and nonclinical factors influencing the type of fetal assessment employed during labor. Seven focus groups with a total of 41 participants were completed. Seven themes were identified: clinical environment; technology; policies, procedures, and evidence-based protocols; patient-centered influences; fear of liability; providers as members of healthcare team; and deflection of responsibility. All maternity care team members had knowledge of the evidence base supporting IA use for low-risk care. Nurses identified unique challenges in having agency over monitoring decision making and executing best practices. Improved communication among team members can facilitate evidence-based approaches to IA use, facilitating increased utilization for low-risk labor care.

[Artificial intelligence technology in cardiac auscultation screening for congenital heart disease: present and future].

The electronic stethoscope combined with artificial intelligence (AI) technology has realized the digital acquisition of heart sounds and intelligent identification of congenital heart disease, which provides objective basis for heart sound auscultation and improves the accuracy of congenital heart disease diagnosis. At the present stage, the AI based cardiac auscultation technique mainly focuses on the research of AI algorithms, and the researchers have designed and summarized a variety of effective algorithms based on the characteristics of cardiac audio data, among which the mel-frequency cepstral coefficients (MFCC) is the most effective one, and widely used in the cardiac auscultation. However, the current cardiac sound analysis techniques are based on specific data sets, and have not been validated in clinic, so the performance of algorithms need to be further verified. The lack of heart sound data, especially the high-quality, standardized, publicly available heart sound database with disease labeling, further restricts the development of heart sound diagnostic analysis and its application in screening. Therefore, expert consensus is necessary in establishing an authoritative heart sound database and standardizing the heart sound auscultation screening process for congenital heart disease. This paper provides an overview of the research and application status of auscultation algorithm and hardware equipment based on AI in auscultation screening of congenital heart disease, and puts forward the problems to be solved in clinical application of AI auscultation screening technology.

Using fetal scalp stimulation with Doppler ultrasonography to enhance intermittent auscultation in low-resource settings: a diagnostic trial from Tanzania.

BACKGROUND: Hypoxia during labor contributes to 2.2 million intrapartum and early neonatal deaths each year. An additional 0.6-1.0 million cases of life-long disability occur because of fetal hypoxia during labor. It is known that fetal heart rate changes in labor correspond to hypoxia and neurologic compromise, but a reliable, low-cost method for detecting these changes is not available. In this study we sought to compare the ability of a handheld Doppler device to detect accelerations as part of the fetal scalp stimulation test and to compare the diagnostic performance of routine intermittent auscultation with auscultation that is augmented with fetal scalp stimulation. METHODS: This non-randomized, pre- and post-diagnostic trial was conducted with 568 maternal-fetus pairs at Kilimanjaro Christian Medical Center in Moshi, Tanzania. The first objective was to determine whether a handheld Doppler device could detect fetal accelerations in labor with reasonable accuracy as compared with a cardiotocography machine. We performed the fetal scalp stimulation test on 50 fetuses during labor using both a handheld Doppler and a cardiotocography machine and compared the outcomes for correlation using the kappa correlation coefficient. During the second objective, two groups of laboring women were monitored either with intermittent auscultation alone per routine protocol (N = 251) or with intermittent auscultation augmented with fetal scalp stimulation per study protocol(N = 267). Diagnostic accuracy of the monitoring method was determined by comparing umbilical cord blood gases immediately after birth with the predicted state of the baby based on monitoring. The analyses included sensitivity, specificity, and positive and negative predictive values. RESULTS: The prevalence of fetal acidemia ranged from 15 to 20%. Adding the fetal scalp stimulation test to intermittent auscultation protocols improved the performance of intermittent auscultation for detecting severe acidemia (pH < 7.0) from 27 to 70% (p = 0.032). The negative predictive value of intermittent auscultation augmented with the fetal scalp stimulation test ranged from 88 to 99% for mild (pH < 7.2) to severe fetal acidemia. CONCLUSIONS: The fetal scalp stimulation test, conducted with a handheld Doppler, is feasible and accurate in a limited resource setting. It is a low-cost solution that merits further evaluation to reduce intrapartum stillbirth and neonatal death in low-income countries. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT02862925 ).

Artificial Intelligence-Assisted Auscultation of Heart Murmurs: Validation by Virtual Clinical Trial.

Artificial intelligence (AI) has potential to improve the accuracy of screening for valvular and congenital heart disease by auscultation. However, despite recent advances in signal processing and classification algorithms focused on heart sounds, clinical acceptance of this technology has been limited, in part due to lack of objective performance data. We hypothesized that a heart murmur detection algorithm could be quantitatively and objectively evaluated by virtual clinical trial. All cases from the Johns Hopkins Cardiac Auscultatory Recording Database (CARD) with either a pathologic murmur, an innocent murmur or no murmur were selected. The test algorithm, developed independently of CARD, analyzed each recording using an automated batch processing protocol. 3180 heart sound recordings from 603 outpatient visits were selected from CARD. Algorithm estimation of heart rate was similar to gold standard. Sensitivity and specificity for detection of pathologic cases were 93% (CI 90-95%) and 81% (CI 75-85%), respectively, with accuracy 88% (CI 85-91%). Performance varied according to algorithm certainty measure, age of patient, heart rate, murmur intensity, location of recording on the chest and pathologic diagnosis. This is the first reported comprehensive and objective evaluation of an AI-based murmur detection algorithm to our knowledge. The test algorithm performed well in this virtual clinical trial. This strategy can be used to efficiently compare performance of other algorithms against the same dataset and improve understanding of the potential clinical usefulness of AI-assisted auscultation.

Implementation of a large-scale simulation-based cardiovascular clinical examination course for undergraduate medical students - a pilot study.

BACKGROUND: We report the implementation of a large-scale simulation-based cardiovascular diagnostics course for undergraduate medical students. METHODS: A simulation-based course was integrated into the curriculum of second-year medical students (> 400 students/year). The first session aimed at teaching cardiac auscultation skills on mannequins and the second at teaching blood pressure measurement, peripheral arterial examination, and the clinical examination of heart failure in a technical skill-based manner and in a scenario. RESULTS: A total of 414 (99.8%) and 402 (98.5%) students, as well as 102 and 104 educators, participated during the 2016-2017 and 2017-2018 academic years across both types of sessions. The number of positive appreciations by students was high and improved from the first to the second year (session 1: 77% vs. 98%, session 2: 89% vs. 98%; p < 0.0001). Similar results were observed for educators (session 1: 84% vs. 98%, p = 0.007; session 2: 82% vs. 98%, p = 0.01). Feedbacks by students were positive regarding the usefulness of the course, fulfillment of pedagogical objectives, quality of the teaching method, time management, and educator-student interactivity. In contrast, 95% of students criticized the quality of the mannequins during the first year leading to the replacement of the simulation material the following year. Students most appreciated the auscultation workshop (25%), the practical aspect of the course (22%), and the availability of educators (21%). CONCLUSIONS: Despite the need to commit significant human and material resources, the implementation of this large-scale program involving > 400 students/year was feasible, and students and educators reacted favorably.

The modified Peyton approach in the teaching of cardiac auscultation.

BACKGROUND: The aim of the study was to evaluate the usefulness of the modified Peyton's four-step approach in the teaching of cardiac auscultation and to determine students' perception of Peyton's four-step approach. METHODS: The opinion of the participants on the usefulness of the modified four-step approach was attained through the use of anonymous questionnaires, voluntarily completed by students, and on the basis of semi-structured interviews conducted with a subset of students. 187 second-year students of our 6-year long curriculum were enrolled. They attended an obligatory Laboratory Training of Clinical Skills course. The average group size was 16 students. RESULTS: The survey findings identified that 88.1% of participants found it helpful in developing their understanding of cardiac auscultation. 89.8% of all participants claimed that the new modified four-step approach facilitated memorization. The modified Peyton's four-step method allows for better organization of classes in the opinion of 87.6% students. The advantages of the method were noticed by the majority of students. CONCLUSIONS: The modified Peyton's four-step approach in the teaching of cardiac auscultation under laboratory conditions was perceived by students to be a comprehensible method that facilitates understanding and memorization. This approach allows for improved organization of classes. From the student's perspective this method allows one to master the technique of cardiac auscultation in the classroom, through the increased demand of the participants' attention, activity and involvement.

Cardiac auscultation: Using physiologic maneuvers to further identify heart murmurs.

Auscultation of heart sounds and murmurs often is taught in a simulated environment with optimal listening conditions. Clinicians' auscultation skills can wither if they do not have contact with patients with valvular heart disease during clinical practice, or if they rely on handheld ultrasound devices or echocardiography. This article reviews heart murmurs and how to use physiologic maneuvers during the cardiac examination to assist in identifying murmurs.

Effect of the Valsalva Maneuver on the Second Heart Sound.

The Valsalva maneuver should be incorporated into the routine of auscultation even when a murmur is absent. Valsalva release affects the second heart sound. It is particularly helpful during detailed, non-perfunctory auscultation in patients with bundle branch block.

Development of a Smartphone App for Visualizing Heart Sounds and Murmurs.

BACKGROUND: Auscultation is one of the basic techniques for the diagnosis of heart disease. However, the interpretation of heart sounds and murmurs is a highly subjective and difficult skill. OBJECTIVES: To assist the auscultation skill at the bedside, a handy phonocardiogram was developed using a smartphone (Samsung Galaxy J, Android OS 4.4.2) and an external microphone attached to a stethoscope. METHODS AND RESULTS: The Android app used Java classes, "AudioRecord," "AudioTrack," and "View," that recorded sounds, replayed sounds, and plotted sound waves, respectively. Sound waves were visualized in real-time, simultaneously replayed on the smartphone, and saved to WAV files. To confirm the availability of the app, 26 kinds of heart sounds and murmurs sounded on a human patient simulator were recorded using three different methods: a bell-type stethoscope, a diaphragm-type stethoscope, and a direct external microphone without a stethoscope. The recorded waveforms were subjectively confirmed and were found to be similar to the reference waveforms. CONCLUSIONS: The real-time visualization of the sound waves on the smartphone may help novices to readily recognize and learn to distinguish the various heart sounds and murmurs in real-time.

Cardiotocography versus intermittent auscultation of fetal heart on admission to labour ward for assessment of fetal wellbeing.

BACKGROUND: The admission cardiotocograph (CTG) is a commonly used screening test consisting of a short (usually 20 minutes) recording of the fetal heart rate (FHR) and uterine activity performed on the mother's admission to the labour ward. This is an update of a review published in 2012. OBJECTIVES: To compare the effects of admission cardiotocography with intermittent auscultation of the FHR on maternal and infant outcomes for pregnant women without risk factors on their admission to the labour ward. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register to 30 November 2016 and we planned to review the reference list of retrieved papers SELECTION CRITERIA: All randomised and quasi-randomised trials comparing admission CTG with intermittent auscultation of the FHR for pregnant women between 37 and 42 completed weeks of pregnancy and considered to be at low risk of intrapartum fetal hypoxia and of developing complications during labour. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial eligibility and quality, and extracted data. Data were checked for accuracy. MAIN RESULTS: We included no new trials in this update. We included four trials involving more than 13,000 women which were conducted in the UK and Ireland and included women in labour. Three trials were funded by the hospitals where the trials took place and one trial was funded by the Scottish government. No declarations of interest were made in two trials; the remaining two trials did not mention declarations of interest. Overall, the studies were assessed as low risk of bias. Results reported in the 2012 review remain unchanged.Although not statistically significant using a strict P < 0.05 criterion, data were consistent with women allocated to admission CTG having, on average, a higher probability of an increase in incidence of caesarean section than women allocated to intermittent auscultation (risk ratio (RR) 1.20, 95% confidence interval (CI) 1.00 to 1.44, 4 trials, 11,338 women, I² = 0%, moderate quality evidence). There was no clear difference in the average treatment effect across included trials between women allocated to admission CTG and women allocated to intermittent auscultation in instrumental vaginal birth (RR 1.10, 95% CI 0.95 to 1.27, 4 trials, 11,338 women, I² = 38%, low quality evidence) and perinatal mortality rate (RR 1.01, 95% CI 0.30 to 3.47, 4 trials, 11,339 infants, I² = 0%, moderate quality evidence).Women allocated to admission CTG had, on average, higher rates of continuous electronic fetal monitoring during labour (RR 1.30, 95% CI 1.14 to 1.48, 3 trials, 10,753 women, I² = 79%, low quality evidence) and fetal blood sampling (RR 1.28, 95% CI 1.13 to 1.45, 3 trials, 10,757 women, I² = 0%) than women allocated to intermittent auscultation. There were no differences between groups in other secondary outcome measures including incidence and severity of hypoxic ischaemic encephalopathy (incidence only reported) (RR 1.19, 95% CI 0.37 to 3.90; 2367 infants; 1 trial; very low quality evidence) and incidence of seizures in the neonatal period (RR 0.72, 95% CI 0.32 to 1.61; 8056 infants; 1 trial; low quality evidence). There were no data reported for severe neurodevelopmental disability assessed at greater than, or equal to, 12 months of age. AUTHORS' CONCLUSIONS: Contrary to continued use in some clinical areas, we found no evidence of benefit for the use of the admission CTG for low-risk women on admission in labour.Furthermore, the probability is that admission CTG increases the caesarean section rate by approximately 20%. The data lacked power to detect possible important differences in perinatal mortality. However, it is unlikely that any trial, or meta-analysis, will be adequately powered to detect such differences. The findings of this review support recommendations that the admission CTG not be used for women who are low risk on admission in labour. Women should be informed that admission CTG is likely associated with an increase in the incidence of caesarean section without evidence of benefit.Evidence quality ranged from moderate to very low, with downgrading decisions based on imprecision, inconsistency and a lack of blinding for participants and personnel. All four included trials were conducted in developed Western European countries. One additional study is ongoing.The usefulness of the findings of this review for developing countries will depend on FHR monitoring practices. However, an absence of benefit and likely harm associated with admission CTG will have relevance for countries where questions are being asked about the role of the admission CTG.Future studies evaluating the effects of the admission CTG should consider including women admitted with signs of labour and before a formal diagnosis of labour. This would include a cohort of women currently having admission CTGs and not included in current trials.

Continuous cardiotocography (CTG) as a form of electronic fetal monitoring (EFM) for fetal assessment during labour.

BACKGROUND: Cardiotocography (CTG) records changes in the fetal heart rate and their temporal relationship to uterine contractions. The aim is to identify babies who may be short of oxygen (hypoxic) to guide additional assessments of fetal wellbeing, or determine if the baby needs to be delivered by caesarean section or instrumental vaginal birth. This is an update of a review previously published in 2013, 2006 and 2001. OBJECTIVES: To evaluate the effectiveness and safety of continuous cardiotocography when used as a method to monitor fetal wellbeing during labour. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group Trials Register (30 November 2016) and reference lists of retrieved studies. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials involving a comparison of continuous cardiotocography (with and without fetal blood sampling) with no fetal monitoring, intermittent auscultation intermittent cardiotocography. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility, quality and extracted data from included studies. Data were checked for accuracy. MAIN RESULTS: We included 13 trials involving over 37,000 women. No new studies were included in this update.One trial (4044 women) compared continuous CTG with intermittent CTG, all other trials compared continuous CTG with intermittent auscultation. No data were found comparing no fetal monitoring with continuous CTG. Overall, methodological quality was mixed. All included studies were at high risk of performance bias, unclear or high risk of detection bias, and unclear risk of reporting bias. Only two trials were assessed at high methodological quality.Compared with intermittent auscultation, continuous cardiotocography showed no significant improvement in overall perinatal death rate (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.59 to 1.23, N = 33,513, 11 trials, low quality evidence), but was associated with halving neonatal seizure rates (RR 0.50, 95% CI 0.31 to 0.80, N = 32,386, 9 trials, moderate quality evidence). There was no difference in cerebral palsy rates (RR 1.75, 95% CI 0.84 to 3.63, N = 13,252, 2 trials, low quality evidence). There was an increase in caesarean sections associated with continuous CTG (RR 1.63, 95% CI 1.29 to 2.07, N = 18,861, 11 trials, low quality evidence). Women were also more likely to have instrumental vaginal births (RR 1.15, 95% CI 1.01 to 1.33, N = 18,615, 10 trials, low quality evidence). There was no difference in the incidence of cord blood acidosis (RR 0.92, 95% CI 0.27 to 3.11, N = 2494, 2 trials, very low quality evidence) or use of any pharmacological analgesia (RR 0.98, 95% CI 0.88 to 1.09, N = 1677, 3 trials, low quality evidence).Compared with intermittent CTG, continuous CTG made no difference to caesarean section rates (RR 1.29, 95% CI 0.84 to 1.97, N = 4044, 1 trial) or instrumental births (RR 1.16, 95% CI 0.92 to 1.46, N = 4044, 1 trial). Less cord blood acidosis was observed in women who had intermittent CTG, however, this result could have been due to chance (RR 1.43, 95% CI 0.95 to 2.14, N = 4044, 1 trial).Data for low risk, high risk, preterm pregnancy and high-quality trials subgroups were consistent with overall results. Access to fetal blood sampling did not appear to influence differences in neonatal seizures or other outcomes.Evidence was assessed using GRADE. Most outcomes were graded as low quality evidence (rates of perinatal death, cerebral palsy, caesarean section, instrumental vaginal births, and any pharmacological analgesia), and downgraded for limitations in design, inconsistency and imprecision of results. The remaining outcomes were downgraded to moderate quality (neonatal seizures) and very low quality (cord blood acidosis) due to similar concerns over limitations in design, inconsistency and imprecision. AUTHORS' CONCLUSIONS: CTG during labour is associated with reduced rates of neonatal seizures, but no clear differences in cerebral palsy, infant mortality or other standard measures of neonatal wellbeing. However, continuous CTG was associated with an increase in caesarean sections and instrumental vaginal births. The challenge is how best to convey these results to women to enable them to make an informed decision without compromising the normality of labour.The question remains as to whether future randomised trials should measure efficacy (the intrinsic value of continuous CTG in trying to prevent adverse neonatal outcomes under optimal clinical conditions) or effectiveness (the effect of this technique in routine clinical practice).Along with the need for further investigations into long-term effects of operative births for women and babies, much remains to be learned about the causation and possible links between antenatal or intrapartum events, neonatal seizures and long-term neurodevelopmental outcomes, whilst considering changes in clinical practice over the intervening years (one-to-one-support during labour, caesarean section rates). The large number of babies randomised to the trials in this review have now reached adulthood and could potentially provide a unique opportunity to clarify if a reduction in neonatal seizures is something inconsequential that should not greatly influence women's and clinicians' choices, or if seizure reduction leads to long-term benefits for babies. Defining meaningful neurological and behavioural outcomes that could be measured in large cohorts of young adults poses huge challenges. However, it is important to collect data from these women and babies while medical records still exist, where possible describe women's mobility and positions during labour and birth, and clarify if these might impact on outcomes. Research should also address the possible contribution of the supine position to adverse outcomes for babies, and assess whether the use of mobility and positions can further reduce the low incidence of neonatal seizures and improve psychological outcomes for women.

Initial Field Test of a Cloud-Based Cardiac Auscultation System to Determine Murmur Etiology in Rural China.

A system for collection, distribution, and long distant, asynchronous interpretation of cardiac auscultation has been developed and field-tested in rural China. We initiated a proof-of-concept test as a critical component of design of a system to allow rural physicians with little experience in evaluation of congenital heart disease (CHD) to obtain assistance in diagnosis and management of children with significant heart disease. The project tested the hypothesis that acceptable screening of heart murmurs could be accomplished using a digital stethoscope and internet cloud transmittal to deliver phonocardiograms to an experienced observer. Of the 7993 children who underwent school-based screening in the Menghai District of Yunnan Province, Peoples Republic of China, 149 had a murmur noted by a screener. They had digital heart sounds and phonocardiograms collected with the HeartLink tele auscultation system, and underwent echocardiography by a cardiology resident from the First Affiliated Hospital of Kunming Medical University. The digital phonocardiograms, stored on a cloud server, were later remotely reviewed by a board-certified American pediatric cardiologist. Fourteen of these subjects were found to have CHD confirmed by echocardiogram. Using the HeartLink system, the pediatric cardiologist identified 11 of the 14 subjects with pathological murmurs, and missed three subjects with atrial septal defects, which were incorrectly identified as venous hum or Still's murmur. In addition, ten subjects were recorded as having pathological murmurs, when no CHD was confirmed by echocardiography during the field study. The overall test accuracy was 91% with 78.5% sensitivity and 92.6% specificity. This proof-of-concept study demonstrated the feasibility of differentiating pathologic murmurs due to CHD from normal functional heart murmurs with the HeartLink system. This field study is an initial step to develop a cost-effective CHD screening strategy in low-resource settings with a shortage of trained medical professionals and pediatric heart programs.

Accidental Heart Murmurs.

INTRODUCTION: Accidental murmurs occur in anatomically and physiologically normal heart. Accidental (innocent) murmurs have their own clearly defined clinical characteristics (asymptomatic, they require minimal follow-up care). AIM: To point out the significance of auscultation of the heart in the differentiation of heart murmurs and show clinical characteristics of accidental heart murmurs. MATERIAL AND METHODS: Article presents review of literature which deals with the issue of accidental heart murmurs in the pediatric cardiology. RESULTS: In the group of accidental murmurs we include classic vibratory parasternal-precordial Stills murmur, pulmonary ejection murmur, the systolic murmur of pulmonary flow in neonates, venous hum, carotid bruit, Potaine murmur, benign cephalic murmur and mammary souffle. CONCLUSION: Accidental heart murmurs are revealed by auscultation in over 50% of children and youth, with a peak occurrence between 3-6 years or 8-12 years of life. Reducing the frequency of murmurs in the later period can be related to poor conduction of the murmur, although the disappearance of murmur in principle is not expected. It is the most common reason of cardiac treatment of the child, and is a common cause of unreasonable concern of parents.

Computer-aided auscultation of murmurs in children: evaluation of commercially available software.

BACKGROUND: Heart murmurs are common in children and may represent congenital or acquired cardiac pathology. Auscultation is challenging and many primary-care physicians lack the skill to differentiate innocent from pathologic murmurs. We sought to determine whether computer-aided auscultation (CardioscanTM) identifies which children require referral to a cardiologist. METHODS: We consecutively enrolled children aged between 0 and 17 years with a murmur, innocent or pathologic, being evaluated in a tertiary-care cardiology clinic. Children being evaluated for the first time and patients with known cardiac pathology were eligible. We excluded children who had undergone cardiac surgery previously or were unable to sit still for auscultation. CardioscanTM auscultation was performed in a quiet room with the subject in the supine position. The sensitivity and specificity of a potentially pathologic murmur designation by CardioscanTM - that is, requiring referral - was determined using echocardiography as the reference standard. RESULTS: We enrolled 126 subjects (44% female) with a median age of 1.7 years, with 93 (74%) having cardiac pathology. The sensitivity and specificity of a potentially pathologic murmur determination by CardioscanTM for identification of cardiac pathology were 83.9 and 30.3%, respectively, versus 75.0 and 71.4%, respectively, when limited to subjects with a heart rate of 50-120 beats per minute. The combination of a CardioscanTM potentially pathologic murmur designation or an abnormal electrocardiogram improved sensitivity to 93.5%, with no haemodynamically significant lesions missed. CONCLUSIONS: Sensitivity of CardioscanTM when interpreted in conjunction with an abnormal electrocardiogram was high, although specificity was poor. Re-evaluation of computer-aided auscultation will remain necessary as advances in this technology become available.

A multi-channel acoustics monitor for perioperative respiratory monitoring: preliminary data.

This study pertains to a six-channel acoustic monitoring system for use in patient monitoring during or after surgery. The base hardware consists of a USB data acquisition system, a custom-built six-channel amplification system, and a series of microphones of various designs. The software is based on the MATLAB platform with data acquisition drivers installed. The displayed information includes: time domain signals, frequency domain signals, and tools to aid in the detection of endobronchial intubation. We hypothesize that the above mentioned arrangement may be helpful to the anesthesiologist in recognizing clinical conditions like wheezing, bronchospasm, endobronchial intubation, and apnea. The study also evaluated various types of microphone designs used to transduce breath sounds. The system also features selectable band-pass filtering using MATLAB algorithms as well as a collection of recordings obtained with the system to establish what respiratory acoustic signals look like under various conditions.

The More Things Change, the More They Stay the Same: Thirty Years of Fetal Monitoring in Perspective.

Thirty years ago, the inaugural issue of The Journal of Perinatal & Neonatal Nursing was published and the entire perinatal portion of the journal was devoted to electronic fetal monitoring (EFM). This article provides a historical perspective on EFM in perinatal care since the 1980s by exploring the similarities and differences of the state of the science presented in that first issue. Both EFM and intermittent auscultation are discussed.

Auscultating heart and breath sounds through patients' gowns: who does this and does it matter?

BACKGROUND: Doctors are taught to auscultate with the stethoscope applied to the skin, but in practice may be seen applying the stethoscope to the gown. OBJECTIVES: To determine how often doctors auscultate heart and breath sounds through patients' gowns, and to assess the impact of this approach on the quality of the sounds heard. METHODS: A sample of doctors in the west of Scotland were sent an email in 2014 inviting them to answer an anonymous questionnaire about how they auscultated heart and breath sounds. Normal heart sounds from two subjects were recorded through skin, through skin and gown, and through skin, gown and dressing gown. These were played to doctors, unaware of the origin of each recording, who completed a questionnaire about the method and quality of the sounds they heard. RESULTS: 206 of 445 (46%) doctors completed the questionnaire. 124 (60%) stated that they listened to patients' heart sounds, and 156 (76%) to patients' breath sounds, through patients' gowns. Trainees were more likely to do this compared with consultants (OR 3.39, 95% CI 1.74 to 6.65). Doctors of all grades considered this practice affected the quality of the sounds heard. 32 doctors listened to the recorded heart sounds. 23 of the 64 (36%) skin and 23 of the 64 (36%) gown recordings were identified. The majority of doctors (74%) could not differentiate between skin or gown recordings, but could tell them apart from the double layer recordings (p=0.02). Trainees were more likely to hear artefactual added sounds (p=0.04). CONCLUSIONS: Many doctors listen to patients' heart and breath sounds through hospital gowns, at least occasionally. In a short test, most doctors could not distinguish between sounds heard through a gown or skin. Further work is needed to determine the impact of this approach to auscultation on the identification of murmurs and added sounds.