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Measurement of cardiac output within the great arteries of infants by non-invasive Doppler echocardiographic techniques is limited. This paper describes a simple method, based on dual beam Doppler, that is capable of measuring the pulmonary and systemic blood flows independently of the vessel diameter and beam-blood flow angle. In 27 babies (12 of them were premature born) without intracardial shunts the accuracy of this method in measuring cardiac output was evaluated. The mean difference between pulmonary and systemic blood flow measurements was 0.02 (SD 0.06) l min. This study demonstrates a good agreement between the pulmonary and systemic blood flow measurements using dual beam Doppler ultrasound in babies. [ABSTRACT FROM PUBLISHER]

Pulsed Doppler signals were recorded from the pulmonary artery and the right ventricular outflow tract in 215 healthy subjects (120 males, 95 females; 1–65 years). Amplitude spectra from these Doppler signals were stored in digital form together with adjustment data for the instrument and the simultaneously recorded ECG. From these Doppler spectra the median of the maximal velocity ( V), the maximal acceleration (A) and the dispersion of the velocity distribution around V (width) were calculated. These three median values were used to characterize the Doppler spectra and to define normal values for bloodflow velocities. Thus, calculations were made without observer interaction using a well-defined computer program. The effect of age, gender, body surface area and heart rate were studied. Reference ranges were calculated. There is a slight decrease of the median value of V and A in the pulmonary artery during lifetime from 80 to 70 cm s and from 1200 to 800 cms, respectively. On the other hand, there is no correlation between age and V and A in the right ventricular outflow tract. The width of the spectra increases with age at both sites. No significant changes with age were seen with the other variables. [ABSTRACT FROM PUBLISHER]

Pulsed Doppler measurements on both sides of the mitral valve and M-mode left ventricular echocardiograms were performed in 215 healthy subjects, 120 males and 95 females, between one and 65 years old, in order to evaluate normal diastolic filling patterns of the left ventricle. The relation between the maximum blood velocity during early passive filling (Ewave) and during atrial contraction (A wave) was computed from the Doppler spectra obtained proximal and distal to the mitral valve, resulting in the EA ratio. The influence on the EA ratio of age, gender, body surface area, blood pressure, heart rate, PR interval, respiration, wall thickness and basal wall mass of the left ventricle was investigated. The study showed that the EA ratio measured proximal to the mitral valve (in the left atrium) was significantly smaller than the EA ratio measured distal (in the left ventricle) and that the only prominent relations with the EA ratio were those with age and heart rate. The EA ratio declines with age: proximal to the mitral valve from approximately (medians) 2.5 to 1 and distal to it from 3.5 to 1.5. All other physiological variables are weakly related or unrelated to the EA ratio in this group of healthy subjects. [ABSTRACT FROM PUBLISHER]

Pulsed Doppler signals were recorded in 215 healthy subjects, 120 males and 95 females, between 1 and 65 years of age. The measurements were performed in the left ventricular outflow tract (LVOT) and in the ascending aorta (AAO). Amplitude spectra from the Doppler signals were stored in digital form together with adjustment data for the instrument, the simultaneously registered ECG and respiration signal. The maximum velocity (Vmax, the maximum acceleration (Amax) and the width of the velocity distribution around Vmax (width) were derived from these spectra and used for the characterization of the signals. These parameters were computed without observer interaction using a computer program. Effects of age, sex, body surface area, heart rate and respiration were studied. Reference ranges were calculated. The following conclusions can be drawn: Vmax and Amax in the AAO decrease clearly with increasing age from approximately 100 to 60 cm s-1 and from 2000 to 1000 cm s-2 (medians), respectively. The variation of the width in the AAO is greater for people over 45 years. Vmax, Amaxand width in the LVOT increase slightly with advancing age from approximately 60 to 80 cm s-1, 800 to 1000 cm s-2 and 12 to 15 cm s-1 (medians), respectively. These parameters of flow were either unrelated or only weakly related to other physiological variables in this study group. [ABSTRACT FROM PUBLISHER]

Small ventricular septal defects (VSDs) with left to right (L–R) shunt have been difficult to diagnose with conventional ultrasound techniques. Using the cross-sectional Doppler flow imaging system, additional information can be obtained. In a group of 60 patients with a clinical diagnosis ofVSD with L–R shunt, the new technique proved valuable, especially in detecting muscular and apical VSDs. [ABSTRACT FROM PUBLISHER]

Two photographs about intestinal obstruction after colostomy closure are presented.