A relative value method for measuring and evaluating neonatal cardiac reserve.

Objective. To devise some indicators for measuring and evaluating the neonatal cardiac reserve by using phonocardiogram test (PCGT). Methods. Two hundred and thirty one (231) full term and one hundred and fifty four (154) preterm infants participated in this study. The amplitude ratio of the first heart sound to the second heart sound (S1/S2), the ratio of diastolic to systolic duration (D/S) and the cardiac contractility change trend after stimulation (CCCTS) of the neonates were measured, calculated and analyzed. Results. The S1/S2, D/S and CCCTS of full preterm infants were higher than that of preterm infants. The differences of D/S and CCCTS between them were significant (P<0.05). According to the full term neonatal cardiac reserve data, a normal reference range of full term neonatal cardiac reserve was primarily known. Conclusions. The indicators S1/S2, D/S and CCCTS may be beneficial for evaluating the neonatal cardiac reserve. We can screen out neonates with reduced cardiac reserve by using the phonocardiogram test.

Algoritmo híbrido para segmentação do ventrículo esquerdo em imagens de ecocardiografia bidimensional / Hybrid algorithm for segmentation of the left ventricle in two-dimensional echocardiography

Este trabalho apresenta uma técnica para segmentação automática da cavidade ventricular esquerda em ecocardiogramas bidimensionais. O algoritmo realiza a identificação e a extração das bordas do ventrículo esquerdo, que permite a obtenção de parâmetros clínicos utilizados no diagnóstico de diversas patologias cardíacas. O processo de extração de bordas é constituído de três etapas: o pré-processamento, a segmentação e a detecção do contorno. Na etapa de pré-processamento é realizada, primeiramente, a aplicação de um algoritmo de minimização do ruído mediante técnica que utiliza transformada de wavelets, seguida da aplicação de uma técnica de elevação do contraste, que prepara a imagem para a próxima etapa. Na etapa de segmentação é utilizada a técnica de watersheds. Na última etapa, procedimentos de morfologia matemática são utilizados para detecção e extração do contorno. A avaliação do desempenho da técnica apresentada foi realizada por meio da comparação dos resultados obtidos pela segmentação automática do ventrículo esquerdo com os resultados obtidos com segmentação manual, feita por um especialista. Os resultados obtidos foram também comparados com os resultdos de outras técnicas descritas na literatura. Para os testes do algoritmo foram descritas na literatura. Para os testes de algoritmo foram utilizadas 60 imagens de ecocardiogramas bidimensionais de pacientes atendidos no serviço de ecocardiolografia do Hospital Universitário de Brasília. Os resultados experimentais mostraram um bom desempenho do método, mesmo em imagens de baixa qualidade, sendo esses resultados superiores aos de outros métodos apresentados na literatura.

Auditory cognition - heart beats physiological axis

Electrocardiogram [ECG] tracings were recorded from normal 28 male subjects in response to an attentive auditory task. Data regarding the changes in ECG that occur on listening to the rare tone bursts were calculated and compared with those on listening to frequent tone bursts. P wave showed longer duration and lower amplitude, in response to rare stimuli, indicating longer, but weaker atrial contraction. QRS complex and P-R interval did not show significant differences between the listening of the two types of stimuli. T wave showed shorter duration and lower amplitude on listening to rare stimuli indicating faster and less ventricular relaxation. The present work denoted that not only passive hearing, but also the active listening had changes in the cardiac cycle

Paradoxical interventricular septal movement in patients with bilharzial cor-pulmonale without clinical or phonocardiographic evidences of pulmonary and/or tricuspid regurge

* Twenty eight patients with bilharzial corpulmonale showing no clinical or phonocardiographic evidences of pulmonary and/or tricuspid regurge were the material of the present study. * Interventricular septal motion was studied in all cases and echocardiographic scoring of the degree of pulmonary hypertension was obtained in them. * Abnormal or paradoxical septal motion indicating diastolic overload to the right ventricle was observed in 20%, 22% and 43% of cases with mild, moderate and severe degree of pulmonary hypertension. * Diastolic overloading in these cases is probably due to incipient and clinically occult pulmonary and/or tricuspid regurge whose murmur in beyond the range of human ear audibility. * The presence of diastolic valume overloading in patients of bilharzial cor-pulmonale as evidenced by paradoxical septal motion in the absence of clinically demonstrable pulmonary and/or tricuspid regurge should destract the attention to incipient regurge of either valves