Biomedical subjects

N Amitai

Publications and source records attributed to N Amitai.

3 recordsLinked to original sources

PubMed1979

Echocardiographic diagnosis of pulmonary atresia with intact ventricular septum.

The echocardiographic features of pulmonary valvar atresia with intact ventricular septum are described. The pulmonary valve fails to open during systole: there is a large pre-systolic 'a' wave dip, but the pulmonary valve membrane then returns to its closed diastolic position where it remains for the remainder of the cardiac cycle. The echocardiogram also provides valuable information about right ventricular size, the tricuspid valve, and aorta-mitral and aorta-septal relations.

Cardiomegaly↗

PubMed1979

Serial echocardiography during the first 3 mth of life in normal neonates.

Echocardiography was performed in 13 normal neonates on the first day of life and repeated after 1 wk, 1 mth and 3 mth. Measurements were made of cardiac chamber size and wall thickness, mitral, tricuspid and pulmonary valve motion, right and left ventricular systolic time intervals, and of fractional left ventricular shortening (%deltaS) and mean velocity of circumferential fibre shortening (mean Vcf). During the study there was a relative decrease in right ventricular cavity size and wall thickness with an increase in the pulmonary valve EF slope, indicating a fall in pulmonary artery pressure with regression of the right ventricle. Left ventricular size and thickness increased while LVET became longer, possibly the consequence of an increasing left ventricular afterload. There was not a significant change in %deltaS and mean Vcf during the study period. The greatest change from right to left ventricular preponderance occurred between 1 wk and 1 mth of life and was accompanied by changes in the mean frontal QRS axis of the electrocardiogram. The study shows that significant changes occur in the echocardiogram during the first 3 mth of life; neonatal echocardiograms should be interpreted not only in relation to the baby's weight, but also to its age.

Atrial Function↗

PubMed1978

Left ventricular function in beta-thalassemia and the effect of multiple transfusions.

Left ventricular performance was studied in 23 young patients with severe chronic anemia due to beta-thalassemia major and intermedia. The patients were divided into three groups according to the number of blood transfusions they had received. The left ventricle (LV) was enlarged in patients who had not received blood and larger still in patients who had received multiple transfusions. Echocardiography and systolic time interval measurements showed that systolic function of the LV was good in all the patients and that there was no statistical difference in systolic function in patients who had and those who had not received multiple transfusions. Heart rate was increased in the latter group. Stroke index and cardiac index were high, especially in patients in Group 3. The diastolic closure rate (EF slope) of the anterior mitral leaflet and its amplitude of movement were increased, but less so in Group 3; this may reflect an alteration in diastolic LV distensibility. The results indicate that despite the presence of cardiomegaly and severe clinical congestive heart failure, LV performance is well preserved in patients with beta-thalassemia, even in those who have received repeated blood transfusions. Clinical cardiac failure is the consequence of volume overload and abnormal chamber compliance. There was no evidence in this of a congestive cardiomyopathy.

Adolescent↗