Differential Diagnosis of Asthma and COPD Based on Multivariate Pulmonary Sounds Analysis.

Objective: Asthma and chronic obstructive pulmonary disease (COPD) can be confused in clinical diagnosis due to overlapping symptoms. The purpose of this study is to develop a method based on multivariate pulmonary sounds analysis for differential diagnosis of the two diseases.

Methods: The recorded 14-channel pulmonary sound data are mathematically modeled using multivariate (or, vector) autoregressive (VAR) model, and the model parameters are fed to the classifier.

A Comparison of SVM and GMM-Based Classifier Configurations for Diagnostic Classification of Pulmonary Sounds.

Goal: The aim of this study is to find a useful methodology to classify multiple distinct pulmonary conditions including the healthy condition and various pathological types, using pulmonary sounds data.

Methods: Fourteen-channel pulmonary sounds data of 40 subjects (healthy and pathological, where the pathologies are of obstructive and restrictive types) are modeled using a second order 250-point vector autoregressive model. The estimated model parameters are fed to support vector machine and Gaussian mixture model (GMM) classifiers which are used in various configurations, resulting in eight different methodologies in total.

Computerized diagnosis of respiratory disorders. SVM based classification of VAR model parameters of respiratory sounds.

Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on "Biosignal Interpretation: Advanced METHODS for Studying Cardiovascular and Respiratory Systems".

Objectives: This work proposes an algorithm for diagnostic classification of multi-channel respiratory sounds.

Methods: 14-channel respiratory sounds are modeled assuming a 250-point second order vector autoregressive (VAR) process, and the estimated model parameters are used to feed a support vector machine (SVM) classifier.

Exploring an optimal vector autoregressive model for multi-channel pulmonary sound data.

The purpose of this study is to find a useful mathematical model for multi-channel pulmonary sound data. Vector auto-regressive (VAR) model schema is adopted and the best set of arguments, namely, the order and sample size of the model and the sampling rate of the data, is aimed to be determined. Both conventional prediction error criteria and a set of three new criteria which are derived specifically for pulmonary sound signals are used to evaluate the success of the model.

Acoustic mapping of the lung based on source localization of adventitious respiratory sound components.

The aim of this study is to devise a methodology to estimate and depict the source locations of respiratory adventitious sound components in the lungs, particularly crackles, associated with certain pulmonary diseases. Using the multichannel respiratory sound signals recorded on the chest wall, we have tried to locate the sources of crackling sounds. The source localization is performed using basic independent component analysis (basic ICA) followed by an evaluation of the mixing coefficients in a center of weights approach, where after the ICA, by taking the relevant mixing matrix coefficients and assuming them to be placed on the microphone locations, the estimated sound source location is calculated as the center of those weights.

Autosomal recessive form of congenital cutis laxa: more than the clinical appearance.

Congenital cutis laxa is an uncommon disorder of generalized elastolysis. The clinical picture is characterized by inelastic, loose, hanging skin that gives the appearance of premature aging. The disease is inherited most commonly in a severe autosomal recessive form, or as a relatively benign, autosomal dominant form.

Can subclinical valvitis detected by echocardiography be accepted as evidence of carditis in the diagnosis of acute rheumatic fever?

Aim: Subclinical valvar insufficiency, or valvitis, has recently been identified using Doppler echocardiography in cases of acute rheumatic fever with isolated arthritis or chorea. The prognosis of such patients with acute rheumatic fever and subclinical valvitis is critical when determining the duration of antibiotic prophylaxis. We aimed, therefore, prospectively to investigate the association of silent valvitis in patients having rheumatic fever in the absence of clinical evidence of cardiac involvement, and to evaluate its prognosis.

Congenital sick sinus syndrome with breath holding and severe syncope episodes during infancy. A case report.

Sick sinus syndrome is a rare cause of bradycardia in children without structural heart disease. A case of profound sinus bradycardia, sinus arrest with junctional escape, and pauses in a two-year-old infant with breath-holding and syncope episodes is presented. As a result of these clinical symptoms and electrocardiographic findings, the patient with sick sinus syndrome underwent implantation of transvenous ventricular pacemaker.

Ventricular diastolic filling indices in pulmonary stenosis.

Children with valvar pulmonary stenosis have right ventricular diastolic filling abnormalities that may be due to either right ventricular hypertrophy or right ventricular outflow obstruction. In order to investigate the reason for this abnormality, 23 consecutive cases with pulmonary stenosis (mean age 7.94 +/- 3.

The accuracy of antenatal fetal echocardiography.

The purpose of this study was to evaluate our experience with a group of patients who were either selected by us or referred by an obstetrician or geneticist with the indication of fetal echocardiography. This prospective study was done on 128 cases between 1996-1998. Maternal age range was between 16 and 41 years (mean: 28.

Double outlet left ventricle with subpulmonary ventricular septal defect and pulmonary hypertension.

A two-month old male infant with the rare occurrence of double outlet left ventricle, subpulmonary ventricular septal defect and pulmonary hypertension is presented. The infant was managed temporarily with banding of the pulmonary trunk, with a favorable result, and is scheduled for definitive intraventricular repair.

Echocardiographic assessment of left and right ventricular diastolic functions in children with dilated cardiomyopathy.

We evaluated left and right ventricular diastolic functions by pulsed Doppler echocardiography in 16 children with dilated cardiomyopathy and in 20 healthy age-matched control subjects. The cardiomyopathy group demonstrated an abnormal relaxation pattern of the left ventricle. In the cardiomyopathy group compared to normal subjects, peak early filling velocities (43.

Posterior deviation of left ventricular outflow tract septal components without ventricular septal defect.

Objective: To describe 11 patients with narrowing of the left ventricular outflow tract caused by angular posterior deviation of both the outlet septum and the upper part of trabecular septum, which was diagnosed by cross sectional echocardiography in all and confirmed by angiocardiography in seven.

Results: Four patients had a subaortic systolic pressure gradient ranging from 23 to 70 mm Hg by Doppler echocardiography; cardiac catheterisation showed a significant (60 and 104 mm Hg) systolic pressure gradient in two. In four cases aortic regurgitation and two tricuspid pouches were shown by Doppler echocardiography, angiocardiography, or both.

The angiocardiographic analysis of 73 patients with double-outlet right ventricle.

The purpose of this study was to determine the cardiac anatomy of patients with double-outlet right ventricle by angiocardiography. A total of 73 patients between the ages of one day and 11 years were examined. The aorta was on the right side of the pulmonary artery in 23 cases (32%), right anterior in 20 (27%) and right posterior in 17 cases (23%).

Echocardiography for the diagnosis of congenital cardiac anomalies with multiple lesions.

The purpose of this study was to determine the sensitivity and specificity of echocardiography for the diagnosis of congenital cardiac abnormalities with multiple lesions. The study was carried out on 80 patients (ages 1 day to 14 years). After clinical evaluation all patients were studied by echocardiography.

Heart disease in Friedreich's ataxia: a clinical and echocardiographic study.

Twelve patients with Friedreich's ataxia (FA) were evaluated clinically and echocardiographically for evidence of heart disease. Electrocardiographic and echocardiographic abnormal findings were discovered in eight (67%) and seven (58%) children, respectively. A high incidence of cardiac involvement is well known in FA cases.

Noonan syndrome with double-chambered right ventricle.

The association of Noonan syndrome and a double-chambered right ventricle has not been reported previously in the medical literature. We report two patients with Noonan syndrome associated with pulmonary valve stenosis and double-chambered right ventricle due to anomalous hypertrophied muscle bundles. Pulmonary valve stenosis was operated on.

Subpulmonary and subaortic ridges in doubly committed subarterial ventricular septal defect: an echocardiographic study.

Background: Certain conditions, including discrete subaortic stenosis and right ventricular outflow tract obstruction are well-known associations with ventricular septal defect. However, the association of discrete type subpulmonary and subaortic stenosis with ventricular septal defect has not been described to date.

Patients: In this report we present our experience in nine patients with doubly committed subarterial ventricular septal defect in whom associated discrete subpulmonary and subaortic stenosis were diagnosed by two-dimensional echocardiography.

Parameters of iron deficiency in children with cyanotic congenital heart disease.

A group of 67 children with cyanotic congenital heart disease (CCHD) were studied, and 35 were given iron treatment according to a regimen that gives iron to patients with a hematocrit (Hct) below 60%. The patients were categorized as iron-deficient and iron-sufficient according to their transferrin saturation and ferritin values. The pretreatment hemoglobin (Hb) and Hct values of the groups were similar.

"Acquired" subvalvular aortic stenosis after repair of several congenital cardiac defects.

Discrete subvalvular aortic stenosis is a progressive lesion. In this report we presented nine patients who had no significant left ventricular-aortic obstruction at initial cardiac catheterization or echocardiographic examination, but later developed significant subvalvular aortic stenosis. Associated lesions included ventricular septal defect in three, patent ductus arteriosus in two, aorticopulmonary window in one, tetralogy of Fallot in one, supramitral membrane in one, and ventricular septal defect and patent ductus arteriosus in one case.

Double-chambered right ventricle: experience with 52 cases.

The presence of anomalous muscle bundles may produce a pressure gradient between the inflow and outflow portions of the right ventricle, thus resulting in double-chambered right ventricle bearing troublesome clinically in its diagnosis. The aim of the present study was to review the diagnostic criteria. Fifty-two patients with a double-chambered right ventricle were seen during an 8-year period.

Left ventricular size following shunt operation in tetralogy of Fallot.

This study was performed in 24 patients with tetralogy of Fallot in whom shunt operation was performed instead of total correction because of small left ventricular end-diastolic dimension. Left ventricular end-diastolic dimension was measured using M-mode and two-dimensional echocardiography pre- and at least one year postoperatively. There was no change in the postoperative left ventricular size in two patients.

Partial anomalous pulmonary venous return. Evaluation of 51 cases.

Partial anomalous pulmonary venous return (PAPVR) is a congenital anomaly in which one or more, but not all, of the pulmonary veins are connected to a systemic vein or to the right atrium directly. Its incidence is higher in autopsy series than in clinical series. We report 51 cases of PAPVR diagnosed by cardiac catheterization and evaluated from the aspects of age, sex, type and associated anomalies and diseases.

Intracardiac thrombosis diagnosed by echocardiography in childhood: predisposing and etiological factors.

Eleven cases of intracardiac thrombi caused by different factors including protein-C deficiency are presented for discussion of the etiology and predisposing factors of intracardiac thrombi during infancy and childhood, and to stress the importance of protein-C deficiency as an etiological factor. Thrombi were localised in the left heart in five patients and right heart in five patients. One patient had both-sided thrombi.

Surgical treatment in tetralogy of Fallot diagnosed by echocardiography.

The purpose of this paper is to present the authors' 3-yr experience of echocardiographic examination of patients with the clinical diagnosis of tetralogy of Fallot, and their evaluation for surgical treatment without prior cardiac catheterization. Among the patients with the clinical diagnosis of tetralogy of Fallot 227 had a definite diagnosis made by M-mode, two-dimensional, Doppler and contrast echocardiography. For the diagnosis of tetralogy of Fallot, ventricular septal defect, pulmonary stenosis, and overriding of the aorta were considered to be fundamental.