Artificial neural network-based method of screening heart murmurs in children. (9/133)

BACKGROUND: Early recognition of heart disease is an important goal in pediatrics. Efforts in developing an inexpensive screening device that can assist in the differentiation between innocent and pathological heart murmurs have met with limited success. Artificial neural networks (ANNs) are valuable tools used in complex pattern recognition and classification tasks. The aim of the present study was to train an ANN to distinguish between innocent and pathological murmurs effectively. METHODS AND RESULTS: Using an electronic stethoscope, heart sounds were recorded from 69 patients (37 pathological and 32 innocent murmurs). Sound samples were processed using digital signal analysis and fed into a custom ANN. With optimal settings, sensitivities and specificities of 100% were obtained on the data collected with the ANN classification system developed. For future unknowns, our results suggest the generalization would improve with better representation of all classes in the training data. CONCLUSION: We demonstrated that ANNs show significant potential in their use as an accurate diagnostic tool for the classification of heart sound data into innocent and pathological classes. This technology offers great promise for the development of a device for high-volume screening of children for heart disease.  (+info)

Transient heart murmur in the late neonatal period: its origin and relation to the transition from fetal to neonatal circulation. (10/133)

To elucidate the origin of transient heart murmur during the late neonatal period, we examined 50 neonates with this type of heart murmur and compared them with 50 controls. We serially examined the morphology of and blood flow in the main pulmonary artery (MPA), the right pulmonary artery (RPA), and the left pulmonary arteries (LPA) using two-dimensional and Doppler echocardiography. The heart murmurs were first noticed at 6 to 60 days after birth (mean 33 +/- 14). At that time, the diameters of both the RPA and the LPA in the heart murmur group were significantly smaller than those in the control group, and the velocities of blood flow in the right and left pulmonary arteries in the heart murmur group were significantly greater than those in the control group. When the heart murmur disappeared, the diameters and the flow velocities of both the RPA and the LPA were not different compared with the control group. Two cases in the heart murmur group continued to have a heart murmur and were diagnosed as having intrinsic congenital peripheral pulmonary artery stenosis. In conclusion, our findings suggest that a transient heart murmur in the late neonatal period is caused by transient branch pulmonary arteries stenosis during the transitional circulation from fetus to neonates.  (+info)

Aberrant branch of the bronchoesophageal artery resembling patent ductus arteriosus in a dog. (11/133)

An anomalous shunt between the bronchoesophageal artery and pulmonary artery was diagnosed in a 1-year- old, 3.5 kg female Miniature Dachshund by selective contrast angiography. A cardiac murmur had been observed in the dog during examination at another hospital. The machinery murmur was auscultated at the left side of the base of the heart. Although thoracic radiography revealed mild cardiomegaly, the characteristic findings of patent ductus arteriosus (PDA), including as aortic arch enlargement and pulmonary artery enlargement were not observed. Echocardiography demonstrated shunting of blood flow presumably from the arterial duct at the pulmonary artery carina. Based on the above findings the case was diagnosed as PDA. Angiocardiography was performed to confirm the diagnosis in preparation for surgical treatment, but later we confirmed that the shunt vessel was not PDA, but apparently a branch of the bronchoesophageal artery. The shunt vessel was branching in a complicated manner and shunted to the pulmonary artery.  (+info)

Closure of the ductus arteriosus and development of pulmonary branch stenosis in babies of less than 32 weeks gestation. (12/133)

AIMS: To define how often transient pulmonary branch stenosis (PBS) develops after closure of a patent ductus arteriosus (PDA) in babies born at less than 32 weeks gestation; to describe the natural history of PBS and the relation between PBS and a cardiac murmur. METHODS: Fifty three preterm infants born at a gestational age less than 32 weeks and who had PDA diagnosed on echocardiography were recruited. An echocardiogram was performed on alternate days until the ductus arteriosus closed. If PBS was diagnosed, the baby was followed up until PBS resolved. RESULTS: In 59%, PBS developed in one or both branches after closure of the PDA. In 21%, both pulmonary branches were affected. In 79%, the left pulmonary artery alone was involved but the right side was never affected alone. PBS had resolved in 74% by the time the infants reached 40 weeks, in 95% at a corrected age of 6 weeks, and in 100% at a corrected age of 3 months. There is a better correlation between a cardiac murmur and PBS than between a murmur and PDA. CONCLUSIONS: PBS in preterm infants is usually not present at birth but develops after closure of a PDA. PBS resolves by a corrected age of 3 months. The presence of a murmur after closure of a PDA is usually related to PBS and not to reopening of the ductus arteriosus.  (+info)

Coronary artery fistula: report of three cases. (13/133)

Three children are described with a right coronary artery fistula communicating with a right heart chamber. Each had a continuous murmur like that of a patent ductus arteriosus but situated at a lower level. Aortography established the diagnosis and excluded any accompanying malformation. It is concluded that to prevent complications surgical treatment should be recommended.  (+info)

Main pulmonary artery stenosis caused by fibrocalcified mass in a young infant. (14/133)

We present a rare case of main pulmonary artery stenosis secondary to protruding fibrous material in the main pulmonary artery associated with patent ductus arteriosus. A 1-month-old baby boy manifested cardiac murmur. Echocardiogram showed circumferential high echogenic mass inside the main pulmonary artery with pressure gradient of 49 mmHg and patent ductus arteriosus. The mass did not regress during 3 months' follow-up period. Angiographic images showed that the circular filling defect was located at the main pulmonary artery distal to pulmonary valve, and pulmonary valve and both pulmonary arteries were normal. After surgical removal of the circumferential material and ductus ligation, the pressure gradient became negligible. The material was consisted of scarcely cellular fibrous tissue, abundant coagulum of fibrinous material and dense calcification.  (+info)

Heart murmurs recorded by a sensor based electronic stethoscope and e-mailed for remote assessment. (15/133)

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.  (+info)

A relative value method for measuring and evaluating cardiac reserve. (16/133)

BACKGROUND: Although a very close relationship between the amplitude of the first heart sound (S1) and the cardiac contractility have been proven by previous studies, the absolute value of S1 can not be applied for evaluating cardiac contractility. However, we were able to devise some indicators with relative values for evaluating cardiac function. METHODS: Tests were carried out on a varied group of volunteers. Four indicators were devised: (1) the increase of the amplitude of the first heart sound after accomplishing different exercise workloads, with respect to the amplitude of the first heart sound (S1)recorded at rest was defined as cardiac contractility change trend (CCCT). When the subjects completed the entire designed exercise workload (7000 J), the resulting CCCT was defined as CCCT(1); when only 1/4 of the designed exercise workload was completed, the result was defined as CCCT(1/4). (2) The ratio of S1 amplitude to S2 amplitude (S1/S2). (3) The ratio of S1 amplitude at tricuspid valve auscultation area to that at mitral auscultation area T1/M1 (4) the ratio of diastolic to systolic duration (D/S). Data were expressed as mean +/- SD. RESULTS: CCCT(1/4) was 6.36 +/- 3.01 (n = 67), CCCT(1) was 10.36 +/- 4.2 (n = 33), S1/S2 was 1.89 +/- 0.94 (n = 140), T1/M1 was 1.44 +/- 0.99 (n = 144), and D/S was 1.68 +/- 0.27 (n = 172). CONCLUSIONS: Using indicators CCCT(1/4) and CCCT(1) may be beneficial for evaluating cardiac contractility and cardiac reserve mobilization level, S1/S2 for considering the factor for hypotension, T1/M1 for evaluating the right heart load, and D/S for evaluating diastolic cardiac blood perfusion time.  (+info)