The diagnosis of innocent murmurs in childhood

A randomized, controlled trial of an innovative, multimedia instructional program for acquiring auditory skill in identifying pediatric heart murmurs

Objective

To create a brief, acceptable, innovative method for self-paced learning to enhance recognition of pediatric heart murmurs by medical students, and to demonstrate this method's effectiveness in a randomized, controlled trial.

Materials and methods

A curriculum of six 10-min online learning modules was designed to enable deliberate practice of pediatric cardiac auscultation, using recordings of patients' heart murmurs. Principles of andragogy and multimedia learning were applied to optimize acquisition of this skill. A pretest and posttest, given 4 weeks apart, were created using additional recordings and administered to 87 3rd-year medical students during their pediatric clerkship. They were randomized to have access to the modules after the pretest or after the posttest, and asked to use at least the first 2 of the modules.

Results

47 subjects comprised the Intervention group, and 40 subjects the Control group. On our primary outcome, distinguishing innocent from pathological with at least moderate confidence, the posttest scores were significantly higher for the Intervention group (60.5%) than for the Control group (20.0%). For our secondary outcomes, the 2 groups also differed significantly in the ability to distinguish innocent from pathological murmurs, and in identifying the actual diagnosis. On all 3 outcomes, those Intervention group subjects who accessed 4-6 modules scored higher than those who accessed 0-3 modules, who in turn scored higher than the Control group.

Summary

Applying current principles of adult learning, we have created a teaching program for medical students to learn to recognize common pediatric murmurs. Its effectiveness was demonstrated in a randomized, controlled trial. The program results in a meaningful gain in this skill from 1 h of self-paced training with high acceptance to learners.

Blood pressure and heart rate monitoring in children and adolescent with Still's vibratory murmur

BACKGROUND

Innocent heart murmur is common in healthy infants, children and adolescents. Although most cases are not pathologic, a murmur may be the manifestation of cardiovascular disease. It may also cause or be an indicator of blood pressure (BP) and heart rate (HR) changes.

OBJECTIVE

This study aimed to document changes in BP and HR in children with Still's vibratory murmur (SVM).

METHODS

This study included 226 children with SVM, and the control group included 138 healthy children that were age-, height- and weight-balanced. Patient files and our hospital registry system were retrospectively investigated for laboratory findings and electrocardiography and echocardiography results. In addition, we prospectively performed 24-h ambulatory BP monitoring in both groups.

RESULTS

There were no statistically significant differences in 24-h, daytime and nighttime systolic BP, 24-h and nighttime diastolic BP and nighttime HR between the patient and control groups (P = ns). However, daytime diastolic BP, mean HR and daytime HR were significantly higher in patient group (P = 0.009, 0.039 and 0007, respectively).

CONCLUSIONS

We believe that in the presence of a higher HR and a higher aortic diastolic BP, which may induce hemodynamic changes in the left ventricle, flow turbulence through the aortic valve may increase, increasing the probability of hearing a murmur. ambulatory BP monitoring could be useful to obtain a better picture of these parameters during the 24-h period.

Detecting and recording cardiac murmurs in clinically healthy puppies in first opinion veterinary practice at the first health check

Background

The frequency that cardiac murmurs are identified and recorded in first opinion veterinary practices at the first health check in puppies is unknown. The aims of the study were to assess the agreement between first opinion veterinary practitioners, a veterinary student and a veterinary cardiology specialist on detecting murmurs, and to establish whether abnormal auscultation findings had been recorded in the health certificates of clinically healthy puppies. The study included prospective and retrospective investigations, where the prospectively collected auscultation findings from a veterinary cardiology specialist and a trained veterinary student were compared to auscultation findings recorded by first opinion veterinary practitioners.

Results

Cardiac auscultation was performed on 331 client-owned, clinically healthy dogs at two time points: at age 34–69 days by a first opinion veterinary practitioner and at age 45–76 days, on average 9 days later, by a veterinary cardiology specialist and a trained veterinary student. Agreement among the three was compared for the presence of a murmur. The degree of inter-observer agreement was evaluated using Cohen’s kappa. Auscultation findings, as noted in the pets’ passports, from 331 puppies and 43 different first opinion veterinary practices, were retrospectively reviewed and prospectively compared with auscultation findings from a veterinary cardiology specialist. Agreement between the veterinary cardiology specialist and the first opinion veterinary practitioners was poor (ϰ = 0.01) and significantly different (P < 0.001). First opinion veterinary practitioners had recorded a cardiac murmur in only 1 of the 97 puppies in which the veterinary cardiology specialist detected a murmur. Two-hundred-and-fifty-two puppies were auscultated by both the veterinary cardiology specialist and the student. Their agreement was fair (ϰ = 0.40) and significantly different (P = 0.024). The agreement between the student and a first opinion veterinary practitioner on these 252 puppies was poor (ϰ = 0.03) and significantly different (P < 0.001).

Conclusions

This study shows that soft cardiac murmurs are rarely documented during the first veterinary health check in puppies by first opinion veterinary practitioners. Although soft murmurs may not be clinically relevant, finding and recording them is evidence of a carefully performed auscultation. Missing a non-pathological murmur is not of clinical importance; however, missing a pathological murmur could prove detrimental for the individual puppy.

Impact of echocardiography on parental anxiety in children with innocent murmurs

AIM

Heart murmurs are not uncommon in childhood. Once noted, they may induce appreciable parental anxiety even if the likely diagnosis is that of an innocent murmur. This study aimed to clarify if a confirmatory echocardiogram may increase parental understanding and reduce their anxiety even though the murmur had been diagnosed as being innocent by an experienced paediatric cardiologist.

METHODS

Parents of children referred to a paediatric cardiologist for evaluation of a murmur were asked to complete a State Trait Anxiety Inventory after the cardiologist's clinical diagnosis of an innocent murmur. The questionnaire was repeated after cross-sectional echocardiography to assess if there was a change in the parental understanding regarding their child's murmur and to review their level of anxiety.

RESULTS

Over the time available for the study, 62 parents were recruited consecutively wherever possible. Forty-eight (77%) completed both questionnaires. There was a reduction in the state anxiety level following the echocardiogram in parents who exhibited a high (n = 23) or even a low-level trait anxiety (n = 25) (P < 0.05). Enhanced parental understanding of the diagnosis was also demonstrated.

CONCLUSIONS

Reduced parental anxiety and an increase in their understanding after echocardiography suggested that the procedure may have an important role in the management of innocent murmurs even after the initial reassurance by a paediatric cardiologist.

Age when presumptive innocent cardiac murmurs spontaneously disappear in clinically healthy Cairn terrier puppies

Innocent cardiac murmurs are common findings in Cairn terrier puppies during their first veterinary health check. The age when these murmurs spontaneously disappear is unreported. The purpose of this study was to establish the age when presumably innocent cardiac murmurs disappear in a population of clinically healthy Cairn terrier puppies. Over a period of 9 months, 227 clinically healthy Cairn terrier puppies (median age, 53 days; range, 45-76 days) underwent auscultation by a veterinary cardiology specialist, who identified 82 puppies with a presumably innocent cardiac murmur. Owners of 20 puppies volunteered to return to the clinic for serial rechecks. Owners of three puppies returned only once, therefore these puppies were censored. Hence this longitudinal observational study followed 17 puppies with monthly cardiac auscultation until the disappearance of their murmurs. The median age of the 20 puppies when the murmur was last audible was 65 days (range 52-285 days). The median age of the 17 puppies when the murmur was no longer audible was 87 days (range 71-347 days; 95% confidence interval 63-111 days). Four of the 17 puppies had a murmur after 3 months of age and two of them had a murmur beyond 6 months of age. The oldest puppy to have an audible murmur was 9.5 months old; this murmur was not audible at 11.5 months of age. In most Cairn terrier puppies in this population, the presumably innocent murmur resolved spontaneously by 3 months of age.

Does Echocardiography Have a Role in the Cardiologist's Diagnosis of Innocent Murmurs in Childhood?

BACKGROUND

Innocent murmurs are common in childhood. Echocardiography may diagnose almost all congenital cardiac abnormalities. Earlier studies have suggested that it may be unnecessary when a clinical diagnosis of an innocent murmur is made by an experienced cardiologist. Yet, echocardiography is commonly performed despite such a diagnosis. Is that justifiable?

METHODS

Patients referred to a paediatric cardiologist for evaluation of a murmur were assessed. If an innocent murmur was clinically diagnosed, an echocardiogram and an electrocardiogram were ordered when requested. The cardiologist completed a questionnaire documenting the reasons for the investigations and his degree of confidence in the clinical diagnosis. The parents and patients were informed of the diagnosis and the results of the investigations.

RESULTS

In almost all 62 cases whose murmurs were clinically considered to be innocent, the referring doctor expected an echocardiogram to be performed. Following echocardiography, one patient was found to have a small muscular ventricular septal defect. On review, the murmur was consistent with that diagnosis. Three (3) others had abnormal echocardiograms namely congenitally corrected transposition of great arteries, partial anomalous right upper lobe pulmonary vein, and left ventricular non-compaction. All on review were still considered clinically to have innocent murmurs.

CONCLUSIONS

Despite the competency of the cardiologist, echocardiography diagnosed important but relatively uncommon cardiac abnormalities with prognostic implications that would have been missed if only the clinical examination was performed. Over and above the referring doctor's expectations for an echocardiogram to be performed is the need for the cardiologist to provide a complete and definitive diagnosis.

Evaluation of children with heart murmurs

Cardiac murmurs can be a source of anxiety for both physicians and parents until serious cardiac disorders are excluded. The innocent cardiac murmur is still the most common finding in healthy children and can usually be diagnosed through obtaining a complete history and performing a complete physical examination. However, a cardiac murmur may be the first sign of a structural cardiac disease and should not be ignored. Referral to a pediatric cardiologist for further evaluation is required when murmur assessment is not clear and diagnostic uncertainty is present. Educating and reassuring parents remains an important aspect of this evaluation. This article discusses features of innocent and pathological murmurs and provides an approach to cardiac murmurs in children.

Pre-participation screening for the prevention of sudden cardiac death in athletes

Pre-partecipation screening is the systematic practice of medically evaluating large populations of athletes before participation in sport activities for the purpose of identifying abnormalities that could cause disease progression or sudden death. In order to prevent sudden cardiac death (SCD), cardiovascular screening should include a strategy for excluding high-risk subjects from athletic and vigorous exercise. There are two major screening programmes in the world. In the United States competitive athletes are screened by means of family and personal history and physical examination. In Italy there is a mandatory screening for competitive athletes, which includes a resting electrocardiogram (ECG) for the detection of cardiac abnormalities. The most important issue to be addressed is whether a screened subject is really guaranteed that she/he is not suffering from any cardiac disease or at risk for SCD. Conceivably, the introduction of echocardiogram during the pre-participation screening, could be reasonable, despite the discrete sensitivity of ECG, in raising clinical suspicions of severe cardiac alterations predisposing to SCD. It is clear that the cost-benefit ratio per saved lives of the ECG screening is a benchmark of the Public Health policy. On the contrary, the additional introduction of echocardiography in a large population screening programme seems to be too much expansive for the Public Health and for this reason not easily practicable, even if useful and not invasive. Even if we strongly believe that a saved life is more important than any cost-efficacy evaluation, the issue of the economical impact of this approach should be further assessed.

Pediatric heart murmurs: evaluation and management in primary care

The ability of the NP to discern pediatric heart murmurs is critical for accurate assessment of etiology, appropriate diagnostic testing, and prudent referral when indicated. This review includes an overview of cardiac assessment, distinguishing features of innocent and pathologic murmurs, differential diagnosis of murmurs, and current referral recommendations.

Detection of cardiac pathology: time intervals and spectral analysis

AIM

To develop an objective diagnostic method that facilitates detection of noncyanotic congenital heart diseases.

METHODS

Heart sounds and murmurs were recorded from 60 healthy children and 173 children with noncyanotic congenital heart disease. Time intervals were measured and spectrum of the systolic murmurs analyzed. Stepwise logistic regression analysis was used to distinguish physiological from pathological signals. The receiver operating characteristic (ROC) curve was plotted to show the classification performance of the model and the area under the curve (AUC) was calculated. The probability cut-off points for calculation of sensitivities and specificities were estimated.

RESULTS

The distinguishing variables were the interval from the end of the first heart sound (S(1)) and the beginning of the systolic murmur, respiratory variation of the splitting of the second heart sound, intensity of the systolic murmur, and standard deviation of the interval from the end of the S(1) to the maximum intensity of the murmur. The AUC was 0.95, indicating an excellent classification performance of the model. The sensitivity of 95% and specificity of 72% was achieved at a probability cut-off point of 0.45. Significant cardiac defects were correctly classified.

CONCLUSION

Interval measurements and spectral analysis can be used to confirm significant noncyanotic congenital heart diseases. Further development of the method is necessary to detect also insignificant heart defects.

Phono-spectrographic analysis of heart murmur in children

BACKGROUND

More than 90% of heart murmurs in children are innocent. Frequently the skills of the first examiner are not adequate to differentiate between innocent and pathological murmurs. Our goal was to evaluate the value of a simple and low-cost phonocardiographic recording and analysis system in determining the characteristic features of heart murmurs in children and in distinguishing innocent systolic murmurs from pathological.

METHODS

The system consisting of an electronic stethoscope and a multimedia laptop computer was used for the recording, monitoring and analysis of auscultation findings. The recorded sounds were examined graphically and numerically using combined phono-spectrograms. The data consisted of heart sound recordings from 807 pediatric patients, including 88 normal cases without any murmur, 447 innocent murmurs and 272 pathological murmurs. The phono-spectrographic features of heart murmurs were examined visually and numerically. From this database, 50 innocent vibratory murmurs, 25 innocent ejection murmurs and 50 easily confusable, mildly pathological systolic murmurs were selected to test whether quantitative phono-spectrographic analysis could be used as an accurate screening tool for systolic heart murmurs in children.

RESULTS

The phono-spectrograms of the most common innocent and pathological murmurs were presented as examples of the whole data set. Typically, innocent murmurs had lower frequencies (below 200 Hz) and a frequency spectrum with a more harmonic structure than pathological cases. Quantitative analysis revealed no significant differences in the duration of S1 and S2 or loudness of systolic murmurs between the pathological and physiological systolic murmurs. However, the pathological murmurs included both lower and higher frequencies than the physiological ones (p < 0.001 for both low and high frequency limits). If the systolic murmur contained intensive frequency components of over 200 Hz, or its length accounted for over 80 % of the whole systolic duration, it was considered pathological. Using these criteria, 90 % specificity and 91 % sensitivity in screening were achieved.

CONCLUSION

Phono-spectrographic analysis improves the accuracy of primary heart murmur evaluation and educates inexperienced listener. Using simple quantitative criterias a level of pediatric cardiologist is easily achieved in screening heart murmurs in children.

Heart murmurs recorded by a sensor based electronic stethoscope and e-mailed for remote assessment

BACKGROUND

Heart murmurs are common in children, and they are often referred to a specialist for examination. A clinically innocent murmur does not need further investigation. The referral area of the University Hospital is large and sparsely populated. A new service for remote auscultation (telemedicine) of heart murmurs in children was established where heart sounds and short texts were sent as an attachment to e-mails.

AIM

To assess the clinical quality of this method.

METHODS

Heart sounds from 47 patients with no murmur (n = 7), with innocent murmurs (n = 20), or with pathological murmurs (n = 20) were recorded using a sensor based stethoscope and e-mailed to a remote computer. The sounds were repeated, giving 100 cases that were randomly distributed on a compact disc. Four cardiologists assessed and categorised the cases as having "no murmur", "innocent murmur", or "pathological murmur", recorded the assessment time per case, their degree of certainty, and whether they recommended referral.

RESULTS

On average, 2.1 minutes were spent on each case. The mean sensitivity and specificity were 89.7% and 98.2% respectively, and the inter-observer and intra-observer variabilities were low (kappa 0.81 and 0.87), respectively. A total of 93.4% of cases with a pathological murmur and 12.6% of cases with an innocent murmur were recommended for referral.

CONCLUSION

Telemedical referral of patients with heart murmurs for remote assessment by a cardiologist is safe and saves time. Skilled auscultation is adequate to detect patients with innocent murmurs.