Clinical and echocardiographic evaluation of neonates with heart murmurs

Prevalence and Clinical Significance of Heart Murmurs Detected on Cardiac Auscultation in 856 Cats

Simple Summary

Heart murmurs are a common finding in cats and, in many cases, the presence of an audible murmur on cardiac auscultation does not necessarily imply the presence of an underlying heart disease. Several studies have been published in the past to address the prevalence and clinical significance of heart murmurs in cats, but very few have looked into the exact origin of the blood flow turbulence responsible for this finding. We retrospectively reviewed clinical records and echocardiographic examinations of 856 cats with heart murmur and found that the majority of murmurs are caused by systolic anterior motion of the mitral valve (SAM) (39.2%) and dynamic right ventricular outflow tract obstruction (DRVOTO) (32%). These causes of murmur do not appear associated with a structural cardiac abnormality in 56.1% (SAM) and 85.0% (DRVOTO) of murmurs. This study also demonstrated that some heart murmur characteristics (timing, intensity and location) can occasionally discriminate between normal cats and cats with underlying heart disease, with the exception of loud and palpable murmurs, which are inevitably associated with significant cardiac abnormalities. However, since the majority of heart murmurs in cats appear to be systolic and mild–moderate in loudness, echocardiography should always be considered following identification of a heart murmur on physical examination in cats.

Abstract

Background: Cardiac auscultation is one of the most important clinical tools to identify patients with a potential heart disease. Although several publications have reported the prevalence of murmurs in cats, little information is available in relation to the exact origin of the blood flow turbulences responsible for these murmurs. The aim of this study was to determine the prevalence and clinical significance of murmurs detected during physical examination in cats. Methods: Retrospective evaluation of clinical records and echocardiographic examinations performed in cats for investigation of heart murmurs; Results: Records of 856 cats with full clinical information were available for review. The cause of murmur was identified in 93.1% of cases (72.3% with single blood flow turbulence, 26.4% with two, and 1.3% with three identifiable sources of murmur). Systolic anterior motion of the mitral valve (SAM) was the primary cause of murmur in this population (39.2%), followed by dynamic right ventricular outflow tract obstruction (DRVOTO) (32%) and flow murmurs (6.9%). Most cats with a murmur (56.7%) did not present any structural cardiac abnormality. Conclusions: This study indicates that some heart murmur characteristics (timing, loudness and point of maximal intensity) can potentially predict the presence of an underlying cardiac disease.

Anxiety levels in parents of asymptomatic neonates and young infants referred for echocardiography

INTRODUCTION

Previous studies in children with innocent murmurs have shown that parental concern is common.

METHODS

We assessed the anxiety levels among parents of asymptomatic neonates or infants up-to 6 weeks referred for cardiologic consultation because of a heart murmur. A six-item short-form of the state scale of the Spielberger State-Trait Anxiety Inventory (STAI) was completed by the parents before and after consultation.

RESULTS

The average STAI score decreased from 14.42 ± 4.54 on arrival to 9.69 ± 4.26 after the consultation (p < 0.001). Overall, the parents felt more calm, less tense, less upset, more relaxed, more content and less worried after the consultation (p < 0.001). Multivariable linear regression analysis showed that the STAI score prior to consultation was related to infants age (coefficient β = - 0.172; P = 0.046) and STAI score post consultation was related to the final diagnosis (β = 0.312; P < 0.001).

CONCLUSION

In conclusion, parents of asymptomatic neonates and young infants with a murmur exhibit moderate levels of anxiety which can be ameliorated after consultation. Parental education in the field is of paramount importance and the role of both paediatric cardiologists as well as primary care physicians is crucial and decisive.

Detection of Pathologic Heart Murmurs Using a Piezoelectric Sensor

This study aimed to evaluate the capability of a piezoelectric sensor to detect a heart murmur in patients with congenital heart defects. Heart sounds and murmurs were recorded using a piezoelectric sensor and an electronic stethoscope in healthy neonates (n = 9) and in neonates with systolic murmurs caused by congenital heart defects (n = 9) who were born at a hospital. Signal data were digitally filtered by high-pass filtering, and the envelope of the processed signals was calculated. The amplitudes of systolic murmurs were evaluated using the signal-to-noise ratio and compared between healthy neonates and those with congenital heart defects. In addition, the correlation between the amplitudes of systolic murmurs recorded by the piezoelectric sensor and electronic stethoscope was determined. The amplitudes of systolic murmurs detected by the piezoelectric sensor were significantly higher in neonates with congenital heart defects than in healthy neonates (p < 0.01). Systolic murmurs recorded by the piezoelectric sensor had a strong correlation with those recorded by the electronic stethoscope (ρ = 0.899 and p < 0.01, respectively). The piezoelectric sensor can detect heart murmurs objectively. Mechanical improvement and automatic analysis algorithms are expected to improve recording in the future.

Accuracy of cardiac auscultation in detection of neonatal congenital heart disease by general paediatricians

BACKGROUND

Challenges remain in the judgement of pathological murmurs in newborns at maternity hospitals, and there are still many simple major CHD patients in developing countries who are not diagnosed in a timely fashion. This study aimed to evaluate the accuracy of cardiac auscultation on neonatal CHD by general paediatricians.

METHODS

We conducted a prospective study at three hospitals. All asymptomatic newborns underwent auscultation, pulse oximetry monitoring, and echocardiography. Major CHD was classified and confirmed through follow-up. We evaluated the accuracy of various degrees of murmurs for detecting major CHD to determine the most appropriate standards and time of auscultation.

RESULTS

A total of 6750 newborns were included. The median age of auscultation was 43 hours. Cardiac murmurs were identified in 6.6% of newborns. For all CHD, 44.4% had varying degrees of murmurs. A murmur of grade ≥2 used as a reference standard for major CHD had a sensitivity of 89.58%. The false positive rate of murmurs of grade ≥2 for detecting major CHD was significantly negatively related to auscultation time, with 84.4% of false positives requiring follow-up for non-major CHD cardiac issues. Auscultation after 27 hours of life could reduce the false positive rate of major CHD from 2.7 to 0.9%.

CONCLUSIONS

With appropriate training, maternity hospital's paediatricians can detect major CHD with high detection rates with an acceptable false positive rate.

Heart murmurs and echocardiography findings in the normal newborn nursery

OBJECTIVE

To determine the clinical findings and management implications of echocardiograms performed on infants with murmurs in the nursery.

DESIGN

Retrospective cohort study conducted from January 2008 through December 2015. Patients in the study were followed by chart review for up to 5 years. In addition, a survey of nursery providers was conducted in February 2016.

SETTING

A single community hospital associated with a university.

PATIENTS

All 26 573 infants who received care in the normal newborn nursery were eligible for inclusion in the study. Infants with echocardiograms were analyzed. The survey was sent by e-mail to all 135 physicians who work in the nursery.

OUTCOME MEASURES

The primary outcomes include the specific findings on echocardiogram and whether the findings required an acute change in management, outpatient follow up, or were incidental findings. The primary survey question was how physicians would manage an otherwise asymptomatic newborn with a heart murmur.

RESULTS

Four hundred ninety-nine infants had echocardiograms, and over the study period the utilization of echocardiography increased from 1.02% to 2.56% (P < .001) of all infants. Three hundred fifty-four babies had echocardiography performed because of a heart murmur. One hundred sixty-three (46.0%) of these echocardiograms were normal and 160 (45.2%) had findings that did not require additional care. Twenty-three neonates (6.5%) had echocardiographic findings that necessitated outpatient follow-up and 8 neonates (2.3%) required neonatal intensive care due to the findings on their echocardiogram. In total, 14 infants (4%) would go on to require heart surgery or interventional cardiac catheterization. 63/135 (47%) physicians completed the survey, with wide variations in the management of newborns with heart murmurs.

CONCLUSIONS

The use of echocardiography in the normal newborn nursery has increased with time despite improved prenatal detection of heart disease and the use of pulse oximetry screening, and identifies significant heart disease in a small but important number of infants.

Novel algorithm to screen for heart murmurs using computer-aided auscultation in neonates: a prospective single center pilot observational study

BACKGROUND

Automated detection of heart murmurs with computer-aided auscultation is not yet in clinical routine use. Aim of this study was to test sensitivity and specificity of a novel prototype algorithm in automated detection of heart murmurs from digitally recorded phonocardiograms in neonates admitted at the Neonatal Intensive Care Unit.

METHODS

In a prospective pilot observational study from November 2012 to December 2013 auscultations by pediatricians and computer aided auscultation were performed within 12 hours of neonatal echocardiography. Echocardiography was defined as pathological when resulting in any clinical consequences or causing murmur. Phonocardiograms and auscultation were defined as pathological if a murmur was detected. Phonocardiograms were analyzed offline with a novel algorithm prototype (CSD Labs, Graz, Austria) for detection of murmurs in neonates in a first run and with an optimized algorithm in a second run and were compared with echocardiography. Sensitivity and specificity of auscultation by pediatrician and computer aided auscultation were analyzed.

RESULTS

Thirty-six neonates (gestational age: 36±3 weeks) were included. Twenty-three (64%) neonates had pathological or murmur causing findings in echocardiography (positive echocardiography). Sensitivity and specificity of auscultation by pediatrician were 17% and 100%, respectively. In comparison to auscultation by pediatrician sensitivity of first run and second run were significantly higher with 70% and 83%, respectively. Specificity of first run and second run were 77% and 85%, respectively.

CONCLUSIONS

Phonocardiogram analysis using the novel algorithm prototype had a higher sensitivity than auscultation by pediatrician in detecting positive echocardiography findings in neonates.

A Meta-Analysis about the Screening Role of Pulse Oximetry for Congenital Heart Disease

OBJECTIVE

The opinions about the application of pulse oximetry in diagnosis of congenital heart disease (CHD) were debatable. We performed this meta-analysis to confirm the diagnostic role of pulse oximetry screening for CHD.

METHODS

Relevant articles were searched in the databases of Pubmed, Embase, Google Scholar, and Chinese National Knowledge Infrastructure (CNKI) up to April 2017. Data was processed in the MetaDiSc 1.4 software. Pooled sensitivity and specificity with 95% confidence interval (95% CI) were calculated to explain the diagnostic role of pulse oximetry screening for CHD. I2⩾50% or p < 0.05 indicated significant heterogeneity. Area under curve (AUC) of summary receiver operating characteristics (SROC) was calculated to assess its diagnostic accuracy. The robustness of overall results was evaluated by sensitivity analysis. Publication bias was evaluated by Deek's funnel plot.

RESULTS

22 eligible articles were selected. Pooled sensitivity and specificity were 0.69 (0.67-0.72) and 0.99 (0.99-0.99), respectively. The corresponding AUC was 0.9407, suggesting high diagnostic accuracy of pulse oximetry screening for CHD. Sensitivity analysis demonstrated that the pooled results were robust. Deek's funnel plot seemed to be symmetrical.

CONCLUSIONS

Pulse oximetry screening could be used to diagnose CHD. It shows high diagnosis specificity and accuracy.

Impact of telemedicine on hospital transport, length of stay, and medical outcomes in infants with suspected heart disease: a multicenter study

BACKGROUND

Previous single-center studies have shown that telemedicine improves care in newborns with suspected heart disease. The aim of this study was to test the hypothesis that telemedicine would shorten time to diagnosis, prevent unnecessary transports, reduce length of stay, and decrease exposure to invasive treatments.

METHODS

Nine pediatric cardiology centers entered data prospectively on patients aged <6 weeks, matched by gestational age, weight, and diagnosis. Subjects born at hospitals with and without access to telemedicine constituted the study group and control groups, respectively. Data from patients with mild or no heart disease were analyzed.

RESULTS

Data were obtained for 337 matched pairs with mild or no heart disease. Transport to a tertiary care center (4% [n = 15] vs 10% [n = 32], P = .01), mean time to diagnosis (100 vs 147 min, P < .001), mean length of stay (1.0 vs 26 days, P = .005) and length of intensive care unit stay (0.96 vs 2.5 days, P = .024) were significantly less in the telemedicine group. Telemedicine patients were significantly farther from tertiary care hospitals than control subjects. The use of inotropic support and indomethacin was significantly less in the telemedicine group. By multivariate analysis, telemedicine patients were less likely to be transported (odds ratio, 0.44; 95% confidence interval, 0.23-0.83) and less likely to be placed on inotropic support (odds ratio, 0.16; 95% confidence interval, 0.10-0.28).

CONCLUSIONS

Telemedicine shortened the time to diagnosis and significantly decreased the need for transport of infants with mild or no heart disease. The length of hospitalization and intensive care stay and use of indomethacin and inotropic support were less in telemedicine patients.

Benefits of predischarge echocardiography service for postnatal heart murmurs

AIM

To review the findings and outcomes of predischarge echocardiography service for postnatal heart murmurs provided by neonatologists.

METHODS

We retrospectively reviewed all predischarge echocardiograms performed on babies from the postnatal wards (PNW) over the last 3 years. We evaluated the indications, median age, findings and outcome.

RESULTS

A total of 408 echocardiograms were performed on 350 babies on the PNW. The most common indication was presence of a murmur (58%). In babies with a heart murmur, 26% had a normal echocardiogram, 2% had major structural heart defects, 38% had minor structural heart defects and 34% had transient circulatory changes. 32% were discharged with no follow-up, 28% were followed up in the local cardiac clinic and 40% were referred to the cardiologist.

CONCLUSION

Predischarge echocardiography service for postnatal heart murmurs provided by neonatologists has the benefit of providing an early diagnosis, counselling of the parents and arranging appropriate follow-up. It helps to triage the referrals to the cardiologist. We felt that we were able to alleviate parental anxieties by providing a definitive diagnosis and written information prior to discharge from hospital. We strongly believe that this service should only be provided by those appropriately trained and skilled in echocardiography.

Can cardiologists distinguish innocent from pathologic murmurs in neonates?

OBJECTIVES

To determine the sensitivity and specificity of the clinical assessment of murmurs in neonates, as performed by pediatric cardiologists, and to identify clinical features that predict the presence of congenital heart disease (CHD) in this population.

STUDY DESIGN

Neonates (n = 201) referred for outpatient evaluation of a heart murmur were enrolled consecutively. After a clinical evaluation, the cardiologist documented whether the murmur was "likely innocent" or "likely pathologic." The cardiologist repeated his/her assessment after an electrocardiogram. Echocardiography served as the gold standard.

RESULTS

The median age was 12 days (range, 2-31 days). CHD was present in 113 of 201 (56%). Clinical assessment alone identified patients with CHD with a sensitivity of 80.5% (95% CI, 73.2-87.8), specificity of 90.9% (95% CI, 84.9-96.9), positive predictive value of 91.9% (95% CI, 86.6-97.3), and negative predictive value of 78.4% (95% CI, 70.4-86.4). The addition of an electrocardiogram did not improve these test characteristics. Features that were predictive of CHD were murmur quality (P < .0001), location (P = .02), and timing (P = .04). No patients requiring catheter or surgical intervention were missed by clinical assessment.

CONCLUSIONS

The prevalence of CHD in this referral population was high. Clinical assessment detected all complex CHD, although some simple lesions were missed. Murmur quality, location, and timing were predictive of CHD.

The impact of computer-assisted auscultation on physician referrals of asymptomatic patients with heart murmurs

BACKGROUND

As many as 50-70% of asymptomatic children referred for specialist evaluation or echocardiography because of a murmur have no heart disease.

HYPOTHESIS

Computer-assisted auscultation (CAA) can improve the sensitivity and specificity of referrals for evaluation of heart murmurs.

METHODS

Seven board-certified primary care physicians were evaluated both without and with use of a computer-based decision-support system using 100 prerecorded patient heart sounds (55 innocent murmurs, 30 pathological murmurs, 15 without murmur). The sensitivity and specificity of their murmur referral decisions relative to American College of Cardiology/American Heart Association (ACC/AHA) guidelines, and sensitivity and specificity of murmur detection and characterization (innocent versus pathological) were measured.

RESULTS

Sensitivity for detection of murmurs significantly increased with use of CAA from 76.6 to 89.1% (p <0.001), while specificity remained unaffected (80.0 versus 81.0%). Computer-assisted auscultation improved sensitivity of correctly identifying pathological murmur cases from 82.4 to 90.0%, and specificity of correctly identifying benign cases (with innocent or no murmurs) from 74.9 to 88.8%. (p <0.001). Referral sensitivity increased from 86.7 to 92.9%, while specificity increased from 63.5 to 78.6% using CAA (p <0.001).

CONCLUSIONS

Computer-assisted auscultation appears to be a promising new technology for informing the referral decisions of primary care physicians.

Delayed diagnosis of critical congenital cardiovascular malformations (CCVM) and pulse oximetry screening of newborns

OBJECTIVE

Congenital cardiovascular malformations (CCVMs) are relatively common with a prevalence of 5-10 per 1000 live births. Pulse oximetry screening is proposed to identify newborns with critical CCVMs which are missed by routine prenatal ultrasound and by pre-discharge physical examinations. The purpose of this study was to identify the number of infants with a delayed diagnosis of critical CCVMs potentially detectable by pre-discharge pulse oximetry screening.

PATIENTS AND METHODS

Hospital Discharge records in New Jersey from 199-2004 for infants with critical CCVMs were identified using ICD-9 codes. These records were matched to the Electronic Birth Certificate records to identify newborns who were discharged as normal newborns and were later admitted with a diagnosis of critical CCVMs. Chart review was completed on these cases to confirm a delay in diagnosis.

RESULTS

Chart reviews confirmed delayed diagnosis of critical CCVM in 47 infants out of 670,245 births. Coarctation of the Aorta was the most common delayed diagnosis. The age at final diagnosis varied from 3 days to 6.5 months.

CONCLUSIONS

Further examination of pulse oximetry as a routine newborn screening service is warranted. Implementation of pre-discharge pulse oximetry screening for newborns may improve the timely detection of asymptomatic critical CCVMs.

Delayed recognition of congenital heart disease

OBJECTIVE

The aim of this prospective study was to evaluate the proportion of children with delayed recognition of congenital heart disease (CHD).

METHODS

Of the 744 children with CHD primarily diagnosed during a 10 year period in one hospital, the patients were identified where the diagnosis of CHD was established with a significant delay.

RESULTS

Sixty six patients (8.9%) had delayed diagnosis of CHD. Among patients with cyanotic CHD, 10.4% (7 of 67 cases) were referred after they had initially been discharged home from the birth clinic. Among patients with acyanotic CHD, 8.7% (59 of 677) of all children and 35.1% (59 of 168) of the children who required surgery or interventional catheterisation were referred at an age where elective repair should have already been performed or needed immediate treatment because of their haemodynamic status. Of the 66 patients with delayed diagnosis, one infant with cor triatriatum died at admission because of delayed referral and 10 children had severe complications: preoperative cardiogenic shock in seven cases of aortic coarctation and one case of endocardial fibroelastosis, pulmonary hypertensive crisis in one child after delayed repair of a ventricular septal defect, and infectious endocarditis after dental care in a teenager with undiagnosed moderate aortic stenosis, who required Ross operation a few months later.

DISCUSSION AND CONCLUSION

A substantial proportion of CHD was detected with relevant delay. In all cases of late diagnosis, clinical cardiac findings were present that should have alerted the physician on the possible presence of underlying CHD.

How effectively can clinical examination pick up congenital heart disease at birth?

AIMS

To assess what proportion of all cardiac abnormality can be suspected at birth when all clinical examination before discharge is undertaken by a small stable team of clinicians.

METHODS

A prospective audit of all the 14 572 births in a maternity unit only staffed by nurse practitioners between 1996 and 2003.

RESULTS

1.2% of all babies born in the unit were found to have a structural defect (as confirmed by echocardiography) within a year of birth. The number not suspected before discharge declined over time, and only 6% were first suspected after discharge in the last four years of this eight year study. Four potentially life threatening conditions initially went unsuspected in 1996-8, but none after that. A policy of referring every term baby with a murmur at 1 day of age that was still present at 7-10 days resulted in 4.2% requiring cardiac referral; 54% of these babies still had a murmur when assessed one to two weeks later, and 33% had a structural defect. Parents said in independent, retrospectively conducted, interviews that they found it confidence building to have any possible heart defect identified early and the cause of any murmur clearly and authoritatively explained.

CONCLUSIONS

Effective screening requires experience and a clear, structured, referral pathway, but can work much better than most previous reports suggest. Whether staff bring a medical or nursing background to the task may well be of less importance.

The contribution of pulse oximetry to the early detection of congenital heart disease in newborns

Approximately half of all newborns with congenital heart disease are asymptomatic in the first few days of life. Early detection of ductal-dependant cardiac malformations prior to ductal closure is, however, of significant clinical importance, as the treatment outcome is related to the time of diagnosis. Pulse oximetry has been proposed for early detection of congenital heart disease. The aims of the present study were: 1) to determine the effectiveness of a pulse-oximetric screening performed on the first day of life for the detection of congenital heart disease in otherwise healthy newborns and 2) to determine if a pulse-oximetric screening combined with clinical examination is superior in the diagnosis of congenital heart disease to clinical examination alone. This is a prospective, multi-centre study. Postductal pulse oximetry was performed between six and twelve hours of age in all newborns of greater than 35 weeks gestation. If pulse-oximetry-measured arterial oxygen saturation was less than 95%, echocardiography was performed. Pulse oximetry was performed in 3,262 newborns. Twenty-four infants (0.7%) had repeated saturations of less than 95%. Of these infants, 17 had congenital heart disease and five of the remaining seven had persistent pulmonary hypertension. No infant with a ductal-dependant or cyanotic congenital heart disease exhibited saturation values greater or equal to 95%.

CONCLUSION

postductal pulse-oximetric screening in the first few days of life is an effective means for detecting cyanotic congenital heart disease in otherwise healthy newborns.

Cardiac murmurs: echocardiography in the assessment of patients requiring antibiotic prophylaxis for dental treatment

BACKGROUND

Traditionally patients who indicate that they have a heart murmur or who indicate that they have had rheumatic fever are given antibiotic prophylaxis for dental treatment. This is commonly done without further assessment of the patient's actual endocarditis risk. Echocardiography is a non-invasive method of assessing cardiac valve function and haemodynamics.

METHODS

Consecutive patients who were referred to a private practice oral and maxillofacial surgeon for dentoalveolar surgery and indicated that they had a cardiac problem and usually had antibiotic prophylaxis, were evaluated. Those with a clear indication for prophylaxis, for example had prosthetic heart valves or previous infective endocarditis, received antibiotic prophylaxis. Where there was uncertainty, they were referred for an echocardiogram, and if abnormal, a formal cardiology review.

RESULTS

Three hundred and seventy patients out of approximately 20 000 (1.85 per cent) indicated that they had a cardiac murmur and usually received antibiotic prophylaxis for dental treatment between 1 February 1997 and 1 February 2005. Two hundred and sixty-two (71 per cent) were female and 108 (29 per cent) were male; age range 0.7 to 98 years, average 37.6 years. Two hundred and seventy (72 per cent) had normal hearts with no indication for antibiotic prophylaxis. Of the 100 (28 per cent) patients with abnormal findings, they were on average older; 49.5 years, range 0.7 to 87 years. Of these, 50 (14 per cent) met current indications for antibiotic prophylaxis.

CONCLUSION

Patients who present for dental treatment indicating that they require antibiotic prophylaxis for cardiac condition need to be fully evaluated. In this study only 50 of 370 patients (14 per cent) required antibiotic prophylaxis. The remaining 320 (86 per cent) would have no benefit but a risk of adverse reaction to the antibiotic.

A study of congenital cardiac disease in a neonatal population--the validity of echocardiography undertaken by a neonatologist

OBJECTIVES

To estimate the incidence of, and profile the spread of, congenital cardiac defects, and to assess the accuracy of the echocardiographic diagnosis as performed by a neonatologist.

DESIGN

Hospital-based study.

METHODS

All neonates meeting our criterions, specifically those with a persistent murmur 48 hours after birth, underwent an echocardiographic examination to exclude an underlying congenital cardiac defect. All scans performed by the neonatologist were videotaped and reviewed by a paediatric cardiologist. We assessed concordance according to inter-rater agreement.

RESULTS

Out of 11,085 live births, there were 83 infants with a congenital cardiac defect, giving an incidence of 7.49 per 1000 live births, with 95% confidence interval from 5.88 to 9.09. Of the infants with a murmur persisting at or greater than 48 hours after birth, who had a median age of 4.5 days, 75% had a congenital heart defect, with ventricular septal defect being the commonest, encountered in 56.7% of cases. Concordance between the neonatologist and the cardiologist was good, with Cohen's Kappa coefficient being calculated at 0.68, and 95% confidence interval from 0.51 to 0.85.

CONCLUSION

The incidence of congenital cardiac malformations as determined in our hospital-based study in the United Arab Emirates is similar to that described in the Gulf region and worldwide. A persistent murmur at or greater than 48 hours after birth is strongly suggestive of an underlying congenital cardiac malformation. Our experience shows that a neonatologist appropriately trained in echocardiography can perform as well as a paediatric cardiologist. Where specialist resources are limited, this allows for early diagnosis, earlier referral if necessary, and early institution of appropriate therapy.

Neonatal murmurs: are senior house officers good enough?

AIM

To show that, given appropriate guidelines, senior house officers (SHOs) have the clinical skills required to assess neonatal murmurs.

METHODS

Neonatal SHOs identified babies with a cardiac murmur at routine neonatal examination. The SHOs assessed whether the murmur was significant or innocent and decided between immediate further assessment or echocardiogram as an outpatient.

RESULTS

A total of 112 babies had murmurs at routine neonatal examination. The incidence of cardiac murmurs was 13.8 per 1000. Twelve babies were referred for immediate further assessment. Eleven had structurally abnormal hearts. One had a normal heart with pulmonary hypoplasia. One hundred babies were referred, and 78 attended for outpatient follow up. Of these, the SHO assessed nine babies as having a significant murmur and 69 as having an innocent murmur. Twenty two babies failed to attend for follow up; all were thought to have innocent murmurs. Of the nine murmurs assessed as significant, four were confirmed as such and five were found to be innocent. Of the 91 murmurs assessed as innocent, 63 were proven to be innocent, six had abnormalities on echocardiogram, and 22 defaulted to follow up. Five of the serious murmurs were small ventricular septal defects, which had resolved by 6 months of age; the other had mild pulmonary stenosis. None of these babies were clinically symptomatic at outpatient review.

CONCLUSION

Given appropriate guidelines, SHOs have the skills to assess the significance of, and decide on appropriate management for, neonatal murmurs. Electrocardiograms and chest radiographs are not necessary.

Diagnostic value of the chest radiograph in asymptomatic neonates with a cardiac murmur

AIM

To establish the diagnostic accuracy and diagnostic usefulness of the chest radiograph in asymptomatic neonates with cardiac murmurs.

PATIENTS AND METHODS

The chest radiographs of 68 asymptomatic neonates with cardiac murmurs were analysed retrospectively. The radiographs were anonymized and then evaluated for the presence or absence of cardiac disease by six radiologists, three who regularly interpret neonatal chest radiographs and three who do so infrequently. The eventual diagnosis for each neonate and the impact of the chest radiograph and original report on patient management were established by review of the clinical case notes.

RESULTS

The results for each observer were expressed in 2 x 2 contingency tables and statistical analysis was performed using Fisher's exact test. The radiologists who were experienced in reporting neonatal chest radiographs achieved statistically significant results (P=0.003, P=0.002 and P=0.007) compared with those who were less experienced (P=0.13, P=0.16 and P=0.09). Review of the case notes established that the chest radiograph and original report did not influence clinical management in any of the 68 cases studied.

CONCLUSIONS

Radiologists who frequently report neonatal chest radiographs achieve high accuracy in differentiating cardiac from non-cardiac disease. However, inaccuracies are unavoidable as radiological evidence of cardiac disease is often not present. A false-positive result could cause undue anxiety while a false-negative report could result in the omission of further investigations. Furthermore, a chest radiograph is unlikely to provide the definitive diagnosis. Chest radiographs did not appear to influence patient management in this study and cannot be recommended in the initial evaluation of the asymptomatic neonate with a heart murmur.

Impact of telemedicine on the practice of pediatric cardiology in community hospitals

BACKGROUND

Tele-echocardiography has the potential to bring real-time diagnoses to neonatal facilities without in-house pediatric cardiologists. Many neonates in rural areas, smaller cities, and community hospitals do not have immediate access to pediatric sonographers or echocardiogram interpretation by pediatric cardiologists. This can result in suboptimal echocardiogram quality, delay in initiation of medical intervention, unnecessary patient transport, and increased medical expenditures. Telemedicine has been used with increased frequency to improve efficiency of pediatric cardiology care in hospitals that are not served by pediatric cardiologists. Initial reports suggest that telecardiology is accurate, improves patient care, is cost-effective, enhances echocardiogram quality, and prevents unnecessary transports of neonates in locations that are not served by pediatric cardiologists.

OBJECTIVE

We report the largest series to evaluate the impact of telemedicine on delivery of pediatric cardiac care in community hospitals. We hypothesized that live telemedicine guidance and interpretation of neonatal echocardiograms from community hospitals is accurate, improves patient care, enhances sonographer proficiency, allows for more efficient physician time management, increases patient referrals, and does not result in increased utilization of echocardiography.

METHODS

Using desktop videoconferencing computers, pediatric cardiologists guided and interpreted pediatric echocardiograms from 2 community hospital nurseries 15 miles from a tertiary care center. Studies were transmitted in real-time using the H.320 videoconferencing protocol over 3 integrated services digital network lines (384 kilobits per second). This resulted in a frame rate of 23 to 30 frames per second. Sonographers who primarily scanned adult patients but had received additional training in echocardiography of infants performed the echocardiograms. Additional views were suggested as deemed necessary by the interpreting physician, and interpretations were made during the videoconference. The results of the echocardiogram and recommendations for patient care were communicated to the referring physician over the telemedicine system. Analyses of accuracy, patient treatment, echocardiogram quality, time to diagnosis, pediatric cardiologist practice time management, patient referral patterns, and echocardiography utilization were conducted prospectively.

RESULTS

A total of 500 studies in 364 patients were transmitted during a 30-month period. The most common indication for echocardiography was to rule out congenital heart disease (208 of 500 studies). Signs and symptoms that prompted this concern included cyanosis, murmur, tachypnea, genetic syndrome, arrhythmia, abnormal fetal echocardiogram, and maternal diabetes. Other indications included suspected patent ductus arteriosus (PDA; 182 of 500 studies), intracardiac clot or catheter position, persistent pulmonary hypertension, and hemodynamic instability. Cardiac diagnoses included complex congenital heart disease (n = 16), noncritical heart disease (n = 107), and PDA (n = 86). Additional diagnoses included persistent pulmonary hypertension (n = 12), septal hypertrophy (n = 18), right atrial mass/clot/vegetation (n = 11), and decreased cardiac function (n = 6). An umbilical venous catheter was visualized in the left atrium in 9% (45 of 500) of all studies. No significant abnormalities were found in 244 studies. Major diagnoses were confirmed by subsequent review of videotape in all studies. Comparison of final videotape interpretation to initial telemedicine diagnosis resulted in 1 minor diagnostic change (membranous versus inlet ventricular septal defect). Echocardiograms were performed in subsequent visits in 264 patients. The diagnosis was altered in 3 patients. Telemedicine had an immediate impact on patient care in 151 transmissions. The most common interventions were indomethacin treatment for PDA (n = 76), retraction of umbilical venous catheters from the left atrium (n = 45), inotropic or anticongestive therapy (n = 19), anticoagulation (n = 8), and prostaglandin infusion (n = 8). Nineteen patients were transported to our hospital because of the telemedicine diagnosis. Inpatient or outpatient cardiology follow-up was recommended in an additional 131 studies and did not result in any change in the initial management. The most common diagnoses in these patients were ventricular septal defect (n = 56), atrial septal defect (n = 21), septal hypertrophy (n = 9), intracardiac thrombosis (n = 8), and pulmonary valve stenosis (n = 4). We speculate that the immediate availability of an echocardiographic diagnosis likely prevented unnecessary transport in 14 cases. Recommendations for additional views or adjustment of echocardiography machine settings were made in 95% of transmissions. Real-time guidance was especially helpful in suprasternal notch and subcostal sagittal imaging. Depth, color Doppler sector size, and color Doppler scale were frequently adjusted from routine adult settings during the teleconference. The average time from request for echocardiogram to completion of the videoconference was 28 +/- 14 minutes. This was significantly shorter than the waiting time (12 +/- 16 hours) for the videotape to be delivered by courier. Telemedicine eliminated the need for consultation in 194 cases and allowed the cardiologist to delay the visit until the end of the day in an additional 26 cases. This resulted in average time savings of 4.2 person-hours/wk based on travel and consultation time. Utilization of echocardiography was similar before (35 of 1000 births) and after (33 of 1000 to 43 of 1000) telemedicine installation. The percentage of neonatal echocardiograms that were interpreted by our practice increased from 63% to 81% at 1 hospital and from 0% to 100% at the other hospital.

CONCLUSION

Real-time transmission of neonatal echocardiograms from community hospitals over 3 integrated services digital network lines is accurate and has the potential to improve patient care, enhance echocardiogram quality, aid sonographer education, and have a positive impact on referral patterns and time management without increasing the utilization of echocardiography.

Telecardiology: potential impact on acute care

Echocardiography is often used to diagnose and exclude important cardiac diagnoses in adults and children. Evolving telemedicine technology has the potential to improve access to echocardiography diagnoses in the intensive care unit, emergency room, and newborn nursery. The two primary modes of telemedicine practice are "store and forward" and "real-time" videoconferencing. A digital echocardiogram (often several one cardiac cycle loops) can be stored at one site and forwarded across a telemedicine network to a receiving station for review at a later time. Pediatric cardiologists often favor "real-time" telemedicine because of the ability to guide sonographers with limited experience in congenital heart disease. A complete telemedicine system requires a modified computer, a low- or high-speed connection, and telemedicine inputs. Several adult and pediatric clinical studies have shown telemedicine to be accurate and cost-effective, improve patient care, enhance echocardiogram quality and sonographer proficiency, and promote practice expansion. Obstacles to widespread implementation of telemedicine include lack of standardization of telemedicine components, confusing legal issues and licensure requirements, and poor reimbursement.

Early diagnosis of congenital heart disease

Routine examination of apparently healthy newborn babies detects less than half of those with congenital cardiac malformations because they are asymptomatic and without signs. More severe cardiac malformations are not detected more easily. A normal clinical examination does not exclude serious congenital cardiac malformation. Left heart obstruction is easily overlooked but often causes serious deterioration in less than 3 weeks. It is important to arrange early echocardiography of babies with signs and to consider cardiac malformation in a sick baby even if a previous routine examination was normal. All babies with Down syndrome should have early expert cardiological assessment.

[Diagnostic value of physical examination and electrocardiogram in the initial evaluation of heart murmurs in children]

OBJECTIVE

To investigate the diagnostic value of the physical examination and electrocardiogram in the evaluation of heart murmur in new patients referred to the pediatric cardiologist.

METHOD

From 1 April to 30 September 1998, all consecutive patients referred to the pediatric cardiology clinic for evaluation of heart murmur were included. They were prospectively categorized with no heart disease, possible heart disease or definite heart disease based on history and physical examination. They then underwent electrocardiogram with which the diagnosis was reevaluated by the pediatric cardiologist. Lastly, a doppler-echocardiography was systematically performed.

RESULTS

In 120 children aged four days to 14 years (median: ten months), 72 (60%) showed abnormalities on doppler-echocardiography and 48 (40%) no heart disease. After physical examination, 52 patients were categorized with no heart disease: 45 patients had a normal doppler-echocardiography; in three of them, the diagnosis was incorrectly modified to possible heart disease on the basis of the electrocardiogram. In the other seven children, the electrocardiogram was normal and the doppler-echocardiography revealed minor (n = 5) or moderate (n = 2) heart defects. Nineteen patients were suspected of having possible heart disease, no diagnosis was modified after analysis of the electrocardiogram and six had normal doppler-echocardiography; 49 patients were correctly diagnosed as having definite heart disease. The sensibility of the physical examination was 90.3%, the specificity was 93.8%, the positive predictive value 95.6% and the negative predictive value 86.5%.

CONCLUSION

The electrocardiogram is of no help in the discrimination between heart disease and no heart disease in children referred to the pediatric cardiologist for a cardiac murmur. The physical examination is able to differentiate children with or without heart disease in most of the cases.

Live transmission of neonatal echocardiograms from underserved areas: accuracy, patient care, and cost

OBJECTIVE

Echocardiography is an important tool in the diagnosis and management of critically ill neonates. The authors hypothesized that live telemedicine guidance and interpretation of neonatal echocardiograms from underserved areas would improve management, prevent unnecessary transports, enhance sonographer proficiency, and result in monetary savings.

MATERIALS AND METHODS

Using personal computers capable of real-time transmission of echocardiograms over three integrated services digital network (ISDN) telephone lines, pediatric cardiologists interpreted echocardiograms, suggested views to sonographers, and made recommendations to neonatologists 200 miles away. Analyses of accuracy, management, echocardiogram quality, time, and costs were carried out prospectively.

RESULTS

Sixty studies were transmitted over 7 months. Indications for echocardiography were suspected congenital heart disease (n = 29), suspected patent ductus arteriosus (PDA) (n = 27), and hemodynamic instability (n = 4). Diagnoses were critical congenital heart disease (n = 4), noncritical heart disease (n = 8), PDA (n = 21), ventricular dysfunction (n = 5), persistent pulmonary hypertension (n = 3), and normal (n = 19). Videotape review confirmed all telemedicine interpretations. The echocardiogram led to immediate change in management in 25 cases (42%), and echocardiogram quality was improved in 53 studies (88%). Time from request to completion of echocardiography was 43+/-30 min. Monetary savings from five avoided transports exceeded all expenses.

CONCLUSION

Live transmission of neonatal echocardiograms over three ISDN lines is diagnostic, improves patient care and echocardiography quality, and is cost effective.

Pediatric echocardiography: applications and limitations

Echocardiography is an extraordinarily useful imaging technique in fetuses, infants, children, and adolescents. Recent technologic innovations have expanded its versatility in the pediatric population. However, limited societal resources, limitations inherent to ultrasound imaging, and numerous imaging options even within the field of pediatric echocardiography necessitate the discriminate and thoughtful use of echocardiography in children. The clinical assessment remains a critical prelude to echocardiographic examination of the pediatric cardiovascular system.

Early clinical screening of neonates for congenital heart defects: the cases we miss

In a population-based study of 35,218 infants born alive during the 15 years from 1982 to 1996, 353 (1%) were diagnosed as having a congenital heart defect, of whom 84 (24%) were diagnosed subsequent to discharge from hospital after birth (2.4/1000). Of these, 40 (48%) had a ventricular septal defect, 14 (17%) an atrial septal defect, 9 (11%) a patent arterial duct, 8 (10%) an aortic stenosis and 13 (15%) other defects. Compared with those in whom diagnosis was made before discharge, the group of patients with defects detected late had an increased prevalence of atrial septal defects, patent arterial duct and aortic stenosis, but less decreased prevalence of ventricular septal defects (p < 0.05). Median age at detection of the defects subsequent to discharge was 6 months (range 2 weeks-11 years). Seven patients (8%) presented with clinical symptoms of cardiac decompensation. The mortality rate was significantly lower in those in whom defects were detected late (1/84; 1%) as compared with those detected immediately after birth (37/269; 14%) (p < 0.05). The total rate for early detection was the same after using one clinical examination (8.2/1000) of newborns as our basic routine instead of two (7.1/1000) (p > 0.05). A substantial proportion of congenital cardiac malformations are detected after discharge from hospital after birth. Some patients with these lesions present with cardiac decompensation and are in need of medication and surgery. One clinical examination of newborns detects congenital malformations of the heart as efficient as two.