No abstract

SUMMARY Recent studies suggest that maximal Doppler velocities measured within the jets that form downstream from stenotic valves can be used to predict aortic valve gradients. To test whether the Doppler method would be useful for evaluation and management of pediatric patients with right ventricular outflow obstruction, we evaluated pulmonary artery flow before catheterization in 16 children with pulmonary valve stenosis. We used a 3. ALTHOUGH the clinical diagnosis of pulmonic stenosis is usually not difficult, mild pulmonic stenosis must occasionally be differentiated from aortic stenosis, ventricular septal aneurysm, or even functional flow murmurs. Additionally, clinical estimation of the severity of pulmonic stenosis can be difficult, especially in postoperative and very young patients. 1 Noninvasive echocardiographic diagnosis of pulmonic stenosis is sometimes difficult. Weyman and associates2 reported their experience with M-mode echocardiographic techniques and showed that a deep pulmonary "a" wave occurred in patients with pulmonary stenosis; however, false-negative diagnoses are common and no quantification of severity has been possible using this observation. of this prospective study was to assess the use of twodimensional echocardiographic Doppler techniques for providing noninvasively derived clinically useful information about the severity of pulmonary stenosis. Methods PatientsSixteen children, ages 1 month to 16 years (mean 4.3 + 2.5 years)( + SEM), 13 with clinically suspected isolated valvular pulmonic stenosis and three with minor pulmonary valve abnormalities (documented by subsequent angiography) accompanying atrial septal defects, were studied. Two of the 16 patients had undergone valvulotomy (neither of these had significant pulmonary insufficiency), and two patients were studied by Doppler pre-as well as postoperatively. All patients underwent cardiac catheterization within 12 hours of the ultrasonic study. Three patients were studied after premredication for catheterization; three patients were studied in the catheterization laboratory, and pressure and Doppler measurements were performed sequentially. During catheterization, after standard light sedation, pressure gradients were recorded during pullback across the pulmonic valve using an end-hole, fluid-filled catheter (

Range gated two-dimensional Doppler echocardiographic methods were evaluated for quantifying pulmonary (QP) to systemic (QS) blood flow ratios. Twenty-one patients were studied, 4 with patent ductus arteriosus, 6 with atrial septal defect and 11 with ventricular septal defect. The Doppler pulmonary to systemic flow (QP:QS) estimation method involved calculating volume flow (liters/min) at a variety of intracardiac sites by using imaging information for flow area and Doppler outputs to calculate mean flow velocity as a function of time. Area volume flows were combined to yield QP:QS ratios. The sites sampled were main pulmonary artery, ascending aorta, mitral valve orifice and subpulmonary right ventricular outflow tract. The overall correlation between Doppler QP:QS estimates and those obtained at cardiac catheterization (n = 18) or radionuclide angiography (n = 3) was r = 0.85 (standard error of the estimate = 0.48:1). These preliminary results suggest that clinical application of this Doppler echocardiographic method should allow noninvasive estimation of the magnitude of cardiac shunts.

Normal two-dimensional pulsed Doppler echocardiographic velocity profiles for sites within the heart and great vessels in a group of 102 normal infants and children are presented. Qualitatively, waveforms mimic expected hemodynamic events at the various sites. All waveforms had a rapid initial deflection followed by spectral broadening after attainment of peak velocity. Quantitative angle-corrected peak velocities were generally lower on the right side than on the left side of the heart. Differences in tricuspid (mean 61.8 cm/s) versus mitral (mean 81.1 cm/s) outflow and pulmonary (mean 76.1 cm/s) versus aortic (mean 88.5 cm/s) outflow were significant (p less than 0.01). The only significant age-related differences were in the pulmonary artery (mean for newborns 67.7 cm/s versus 79.6 cm/s for older children, p less than 0.01). Aortic data obtained from interrogation sites in which flow was close to 0 or 180 degrees were similar, whereas aortic peak velocity data obtained from apical long-axis or subcostal views were greater. These differences were probably induced from inaccuracies in azimuthal (elevational) angles that cannot be measured. These normal Doppler data should be useful for comparisons with data obtained for children with various forms of congenital heart disease that affect flow dynamics.

We report a case of postpartum haemorrhage which was successfully treated by embolization of the uterine artery. This technique is not well known and is thought to be underused in this condition. We wish to alert medical personnel to its role in this life-threatening situation.