Andersons pediatric cardiology 1124

FIG 42.31 Right ventricular angiogram in the anteroposterior and lateral projection demonstrating the domed and stenosed pulmonary valve (top) and allowing measurement of the ventriculoarterial junction (bottom) FIG 42.32 Rotational angiography with three-dimensional reconstruction in a patient with pulmonary valve stenosis and associated stenosis of the left pulmonary artery Once angiography has been obtained, the angiographic catheter is withdrawn and an end-hole catheter utilized to cross the valve It is important to cross the tricuspid valve in a fashion to intubate the major aperture of the valve rather than allowing the catheter to pass between tendinous cords, since the latter can cause avulsion of the tricuspid valve when the denatured balloon catheter is withdrawn after the dilation procedure.88 With end-hole catheters, this can best be accomplished by catching the tip of the catheter in the hepatic vein or right atrial wall to create a curve in the tip of the catheter The tricuspid valve can be crossed with the curved tip by rotating leftward and anteriorly from a position in the right atrium Alternatively, a balloon-tipped catheter is more likely to enter through the central lumen of the valve, even though such a catheter is technically more challenging to direct toward the pulmonary valve in smaller patients The catheter is positioned into either the left- or right-lower-lobe branch pulmonary artery even though the left-lower-lobe branch pulmonary artery usually provides an increased degree of stability to the catheter and wire In neonates, advancing the catheter/wire through the arterial duct into the descending aorta can further enhance the stability needed to advance a balloon catheter across the valve (Fig 42.33; Video 42.5).89 If needed, gentle manual pressure can be used over the inguinal region to fix the tip of the wire while advancing the balloon