Noninvasive prediction of transvalvular pressure gradient in patients with pulmonary stenosis by quantitative two-dimensional echocardiographic Doppler studies.

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 (

A new method to calculate aortic valve area without left heart catheterization.

“…Thus, this Doppler formula is actually a simpler way of calculating the valve area than is the Gorlin formula. Our data demonstrate an excellent correlation between the aortic valve area calculated using this direct Doppler equation and that calculated with 15, 16 have found a good correlation between the peak velocity measured across the aortic valve and the measured peak-to-peak gradient at cardiac catheterization calculated with P = 4V2. We also found a good correlation between these variables.…”

Volumetric velocity measurements in restricted geometries using spiral sampling: a phantom study

“…Measurement of blood flow and blood velocity in stenotic vessels can be used for pressure estimation and subsequent classification of the severity of the occlusion, which can guide the treatment decision [1,2]. A key parameter when estimating pressure gradients over a stenosis is the maximum velocity of the blood during systole, from which the peak pressure gradient can be derived using the simplified or modified Bernoulli equation [3,4].…”

Mild to Moderate Pulmonary Valvular Stenosis in Infant Sometimes Improves to the Condition Unnecessary to Do PTPV: Doppler Echocardiographic Observation.

“…However, unnecessary invasive procedures may be obviated when the transpulmonary valve pressure gradient spontaneously improves, as often occurs in cases of mild to moderate PS. The transpulmonary valve pressure gradient can be estimated from the peak V measured by Doppler echocardiography using a simplified Bernoulli's equation, which is, at present, regarded as the most reliable noninvasive methodology to evaluate the severity of PS (Hatle and Angelsen 1982; Lima et al 1983;Johnson et al 1984;Goldberg 1989). Although some studies on serial catheter data showed spontaneous improvement of the transpulmonary valve gradient in mild to moderate patients of PS (Leuker et al 1970;Danilowicz et al 1975), there are few noninvasive studies on the natural history of PS.…”

“…Although the pressure gradient estimated by simplified Bernoulli's equation was reported to be highly reliable, there are still some potential sources of error (Lima et al 1983;Johnson et al 1984;Goldberg 1989). Peak V can change easily through alterations of cardiac output by crying, motion, or the respiratory condition; thus, as the precise conditions under which this value was taken were not specified by the original observes, there is some doubt about the integrity of the data.…”