Significance of the Doppler-derived gradient across a residual aortic coarctation.

Few data exist which address the significance of the Doppler gradient across a residual narrowing in older children who have had a coarctation repaired. Therefore, we evaluated 11 patients with repaired aortic coarctation with and without residual obstruction by Doppler echocardiography. The Doppler-derived transcoarctation pressure gradient correlated poorly with catheter-measured peak-to-peak and catheter maximal instantaneous gradients when only the maximal velocity across the repair was utilized in the simplified Bernoulli equation, [r = 0.73, standard of error of the estimate (SEE) = 5.0 mmHg and r = 0.56, SEE = 7.6 mmHg, respectively]. However, when the precoarctation velocity was included in the simplified Bernoulli equation, the correlation between Doppler-derived and catheter-measured gradients became excellent. The maximal Doppler gradient correlated well with catheter peak-to-peak gradient (r = 0.95, SEE = 2.2 mmHg) and catheter maximal instantaneous gradient (r = 0.94, SEE = 3.2 mmHg). However, the maximal Doppler gradient slightly overestimated the catheter peak-to-peak gradient and underestimated the catheter maximal instantaneous gradient. The Doppler mean gradient showed excellent correlation with the catheter mean gradient (r = 0.97, SEE = 0.85 mmHg). Precoarctation velocities were generally twofold greater than published normals due to a spatial acceleration phenomenon. All subjects had residual hypoplasia of the transverse aorta such that its transverse diameter was 29% less than, and its cross-sectional area was 50% less than, the ascending and descending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler estimation of pressure gradient in pulmonary stenosis: maximal instantaneous vs peak-to-peak, vs mean catheter gradient.

We undertook a study to identify the hemodynamic significance of a Doppler-derived gradient across a stenotic pulmonary valve. Furthermore, we attempted to define the optimal plane for velocity data acquisition. A total of 17 children with valvar pulmonary stenosis were evaluated using Doppler echocardiography. Flow-velocity profiles were obtained from both the parasternal and subxiphoid windows. Ten of 17 patients were studied before and after balloon valvotomy. Therefore, 27 different transvalvar gradients were assessed by Doppler and these data were compared with the catheter-derived maximal instantaneous, peak-to-peak, and mean pressure gradients. The maximal Doppler gradient correlated well with the catheter-derived peak-to-peak pressure gradient (r = 0.95) and catheter maximal instantaneous pressure gradient (r = 0.95). Although these correlation coefficients were similar, the Doppler maximal gradient consistently overestimated the peak-to-peak catheter gradient by as much as 25%-40%. Such an overestimation was not observed when we compared the maximal Doppler gradient with the catheter-derived maximal instantaneous gradient. Moreover, the regression line of the latter comparison closely approximated the line of identity. The correlation coefficient between Doppler mean and catheter mean gradients was only 0.91. Doppler velocities were best derived when multiple transducer positions were employed to interrogate pulmonary artery velocity.

Diagnosis and treatment of intrapericardial teratoma.

Intrapericardial teratoma is a rare mediastinal tumor that originates from aberrant clusters of multipotential cells from three germinal layers. Previous reports have used the combination of cardiac angiography, CT scan, and echocardiogram to establish the diagnosis prior to surgery. We report a case of intrapericardial teratoma diagnosed noninvasively and removed surgically within the first three days of life. Furthermore, we compare the diagnostic accuracy of echocardiography and computerized tomography (CT), and discuss the superiority of noninvasive evaluation in the management of these critically ill infants.