Heart murmur recognition and segmentation by complexity signatures.

Heart sound analysis has been a topic of investigation for several years. Since heart sounds directly encode the mechanical activity of the heart, they enable the assessment and follow-up of several types of heart disorders in pre-symptomatic states. Murmurs are the most common abnormality signature in many heart disorders. This paper introduces an algorithm for heart murmur identification. In the presence of murmurs, heart sounds exhibit chaotic behavior. In the proposed method this is assessed based upon the nonlinear dynamics of the signal. In order to segment murmurs from other heart sound components, the signal is transformed into a phase space that is later reconstructed using the embedded matrix. Based on the phase space, the complexity and the strength of the signal are computed. These features are the basis for sound component boundary location. The method has been tested with a database of heart sounds that include diverse heart lesions and heart murmurs. The algorithms achieved 91.09% sensitivity and 95.25% specificity.

Third heart sound detection using wavelet transform-simplicity filter.

Heart failure and heart valvar diseases are chronic heart disorders which are potentially diagnosed using heart sound characteristics. Heart sound components S1 and S2 exhibit significant characteristics for valvar dysfunction while pathological S3 sound is a prominent sign for heart failure in elderly people. In this paper, a new automatic detection method of the S3 heart sound is proposed. The method is build upon wavelet transform-simplicity filter which separates S1, S2 and S3 sounds from background noise enabling heart sound segmentation even in the presence of heart murmurs or noise sources. The algorithm uses physiologically inspired criteria to assess the presence of S3 heart sound components and to perform their segmentation. Heart sound samples recorded from children as well as from elderly patients with heart failure were used to test the method. The achieved sensitivity and specificity were 90.35% and 92.35%, respectively.

[Isolated non-compaction of left ventricular myocardium]. / Não compactação isolada do miocárdio ventricular esquerdo.

Noncompaction of the ventricular myocardium, also known as "spongy myocardium", is a rare congenital abnormality resulting from an arrest in the normal endomyocardial embryogenesis. The echocardiographic findings consist of multiple, prominent myocardial trabeculations and deep intratrabecular recesses in communication with the left ventricular cavity. This entity is a not well known cause of dilated cardiomyopathy. Some cases were described as X-linked familial forms. We report the clinical case of a 13-year-old female patient with severe left ventricular disfunction, a very trabeculated left ventricle on echocardiography and two admissions in class IV heart failure.

[Angioplasty in aortic coarctation and recoarctation in children and adolescents]. / Angioplastia na coartação e recoartação da aorta em crianças e adolescentes.

STUDY OBJECTIVE: To determine the efficacy of percutaneous balloon angioplasty in children and adolescents with Coarctation and Recoarctation of the Aorta. DESIGN AND SETTING: We dilated native coarctation and recoarctation after a complete hemodynamic and angiographic assessment of the situation in a young population referred to a university hospital. PATIENTS AND INTERVENTION: In 22 patients with coarctation or recoarctation of the aorta, the systolic pressure gradient and the internal diameter of the stenotic area were measured before and after dilation, with a balloon catheter with an insufflation diameter no greater than the aortic diameter measured at the level of the diagram muscle. No infants were included nor patients with a rare aortic anatomy. RESULTS: A significant gradient reduction from 36.59 +/- 12.03 mm Hg to 10.45 +/- 7.52 mm Hg, as well an increase from 4.54 +/- 2.04 mm to 8.05 +/- 2.82 mm in aortic internal diameter, were achieved with no complications. CONCLUSIONS: Similar results were obtained both in native coarctation and recoarctation without significant complications. Age selection, aortic anatomy and balloon size were the major determinants of success.

Permanent pacing in patients with congenital atrio-ventricular block--experience of 33 cases.

OBJECTIVES: The authors review permanent pacing in patients with congenital atrioventricular block (CAVB) and present their experience in permanent pacing in this pathology. STUDY POPULATION AND METHODS: In a population of 4,355 patients submitted to implantation of permanent pacing between January 1980 and January 1998, 33 (0.75%) had CAVB. The mean age of the patient population with CAVB was 16.7 years (aged from eleven days to 35 years); 33% were below 10 years of age; 16 patients were male. The majority of the patients had symptoms of brain hypoperfusion; two patients had concomitant malignant ventricular tachyarrythmias (one of these with Torsade de Pointes due to congenital long QT syndrome). Transvenous (endocardial) pacing was used in 32 patients (two with previous epicardial pacing and exit block) and epicardial pacing in one. The mode of stimulation used was VVI in three patients, DDD in eight patients, VVIR in 14 patients, DDDR in four patients and VDD in four. Smaller pulse generators were used in children of lower weight. In recent years single lead VDD systems have been preferred whenever technically possible. Vascular access was the left cephalic vein in 17 patients; the left subclavian vein in 14 patients and the right jugular vein in one patient. During a mean follow-up of 6.9 years, two patients with ventricular stimulation systems developed "Pacemaker Syndrome" and required a change of mode of stimulation. Lead fracture and posterior cutaneous necroses were observed in two other patients, who were accordingly submitted to surgical revision. It was deemed necessary, one year later, to increase the lead loop in a child with a permanent pacemaker implanted at eleven days of age. No other complications occurred with the other patients; replacement of the pulse generators was performed in an elective manner. CONCLUSIONS: CAVB is a rare indication for the implantation of a permanent pacemaker. In children, in the majority of cases, endocardial stimulation is possible in spite of the obvious technical difficulties due to low weight. Sequential, more physiological, stimulation systems should be preferred. However, VVIR stimulation systems of smaller dimensions can be the first choice of mode of stimulation in smaller children, mainly due to anatomical and technical limitations.

True double aortic lumen in tetralogy of Fallot.

In an infant with tetralogy of Fallot submitted to angiographic study, a double aortic lumen was found. Although no particular complaints were related to the additional abnormality, we report this case to emphasize the possibility of occurrence of persistent embryonic fifth aortic arch.

[Purulent pericarditis. A 10-year retrospective study]. / Pericardites purulentas. Estudo retrospectivo de 10 anos.

The authors carried out a retrospective study of 10 cases (ages below 11 years) with purulent pericarditis diagnosed and treated at the Coimbra Paediatric Hospital during a 10 year period (1 January 1985-31 December 1994). This study identified an average of 1 case per year, a low age group, low morbidity and nil mortality. Our results were due to early diagnosis and immediate aggressive medico-surgical managements, namely, systemic antibiotics covering the most common organisms during at least 3 weeks coupled with extensive pericardiocentesis associated with saline lavage.

[Cor triatriatum. Echo/Doppler diagnosis followed by immediate surgical correction. Report of a clinical case]. / Cor triatriatum. Diagnóstico por Eco/Doppler seguido de correcção cirúrgica imediata. A propósito de um caso clínico.

As Cor Triatriatum is a rare congenital cardiopathy and benign after corrective surgery, decisive means of diagnosis are essential. The AA review some descriptive theoretical concepts and make reference to the difficulties, present at times, in diagnosis by cardiac catheterization. They consider Eco-Doppler to be the means of excellence for its recognition describing all aspects that point to the diagnosis of this pathology. Described is the case of a 12 month old baby, in whom some semiological findings had lead to a wrong diagnosis. In the discussion, additional diagnosis is eliminated due to some anatomic characteristics defined by echocardiography.

[Right coronary fistula to the right atrium. Diagnosis using Doppler echocardiography with color coding]. / Fístula coronária direita para a aurícula direita. Diagnóstico por Eco Doppler com codificação em cor.

A case of right coronary fistula draining to the right atrium which was diagnosed by Echo Doppler and colour flow mapping is presented. A patent ductus arterious was initially diagnosed clinically on this child and he was been waiting for 2D Echo and Doppler registration. The patient is now on waiting list for corrective surgery and a cardiac catheterization confirmed totally our diagnosis obtained by non invasive methods.