Recommended precautions when using low-osmolality or nonionic contrast agents with vasodilators.

Low-osmolality contrast agents were tested for potential chemical incompatibility with vasodilators commonly used in angiography. A mixture of Hexabrix and papaverine produced a white crystalline precipitate. Hexabrix and tolazoline exhibited transient immiscibility. Injection of a flush solution between vasodilator and contrast agent is recommended as a precaution.

Correlation between intracoronary 201Tl myocardial scanning, coronary angiography and left ventriculography.

One hundred and six patients with angina pectoris who underwent routine coronary angiography and left ventriculography were given intracoronary injection of thallium 201. The myocardial images had excellent resolution because of lack of interference from the background activity. The myocardial images and the left ventriculograms showed 94% correlation. Correlation between scans and EKG was lower. There was no correlation between the degree of coronary artery stenosis and 201Tl scan. Currently, the intracoronary injection of 201Tl at rest does not yield additional information to coronary angiography and left ventriculography.

Anomalous origin of coronary artery in association with aorticopulmonary window.

Aorticopulmonary window associated with anomalous origin of coronary arteries is rare; only 12 cases have been reported previously. Origin of coronary arteries from the communicating bridge is rare, having occurred in only five of these cases. We describe two additional cases of this entity, in one of which the right coronary artery arose from the window proper. We also review the previously reported cases.

MR imaging of Ebstein anomaly: results in four cases.

We performed ECG-gated MR imaging in four patients (4 months-15 years old), all of whom had a previously diagnosed severe form of Ebstein anomaly of the tricuspid valve. The goal was to study the anatomy of this congenital heart defect with MR imaging. The axial and coronal scans provided the best details. All characteristic abnormalities were seen well: the maintained proximal and faulty distal attachment of the anterior tricuspid leaflet, the absence of both septal and posterior tricuspid leaflets, the size and delineation of the anatomically atrialized chamber of the right ventricle, and the small, compressed trabecular portion with the markedly dilated pumping outflow tract of the right ventricle proper. Our results suggest that MR may furnish valuable information in patients with Ebstein anomaly when echocardiography is either inconclusive or technically difficult to perform.

Reconstruction of the four basic cardiac projections from magnetic resonance images: a new aspect.

From 3D MR scans, the authors have constructed 2D "silhouettes" that correspond to standard radiographic views of the heart. These images explicitly demonstrate the relationship of the surface anatomy to the internal anatomy of the heart and serve to indicate what chambers contribute to the heart borders seen on radiographs. The findings depart from conventional wisdom in at least four respects, including: the left atrium contributes to the left heart border in a frontal radiograph in only a minority of subjects, in steep RAO and lateral radiographs, the right ventricle does not always form the anterior heart border, in left anterior oblique radiographs greater than 30 degrees, the anterior heart border is formed predominantly by the right ventricle, and the left ventricle extends more craniad along the posterior margin of the heart than expected.

Prosthetic arterial graft occlusion: a complication of tourniquet use during arteriography.

Tourniquet-induced reactive hyperemia, generally considered a safe procedure for enhancing visualization of the arteries in the distal lower extremity, caused acute occlusion of a Dacron arterial graft in one patient. This rare complication can be avoided through use of an alternative such as a chemical vasodilator in patients with susceptible synthetic vascular grafts.

Nonsurgical treatment of childhood hypertension: embolization of an intrarenal aneurysm.

Renal artery aneurysms are an unusual cause of renovascular hypertension in children. When present in an intrarenal location, they pose a difficult surgical problem and transcatheter embolization may represent an effective alternative treatment.

Spasm of the aortocoronary venous graft.

Two cases of spasm of the coronary artery bypass graft are reported, and the angiographic and clinical findings are discussed. Few previous reports of this entity were found in a search of the literature. The therapeutic implications are also presented.

Focal nodular hyperplasia of the liver imaging by differing modalities.

The logistic approach in diagnosis of focal nodular hyperplasia (FNH) of the liver is discussed, based on the experience with three children. In only one child could the diagnosis be made without angiography. In that child the combination of hypervascularity on the radionuclide angiogram and uptake of the radiocolloid by Kupffer cells was sufficient for the diagnosis of FNH. If the radionuclide scintigraphy is inconclusive, angiography has to be done to show the typical features of FNH, seen in all three patients. Only if scintigraphy and angiography are not able to differentiate FNH from hepatic adenoma, biopsy or exploratory laparotomy is indicated as a final diagnostic procedure. Ultrasonography or computerized tomography is of value only in screening for hepatic mass lesions.

Mirror-image right aortic arch: a proposed mechanism in symptomatic vascular ring.

We describe a rare case of right aortic arch with mirror-image branching and a left ductus arteriosus that form an anomalous vascular ring. The unusual feature of this symptomatic vascular ring is presence of a left (posterior) circumflex descending aorta in lieu of an aortic diverticulum which usually represents the posterior element of the vascular ring associated with right aortic arch and mirror-image branching. This we believe is the seventh reported case of Type 1 right aortic arch and only the third such case with a left circumflex descending aorta. Accurate diagnosis was made by barium esophagogram and angiocardiogram and was confirmed surgically. We propose a new theory as to why some vascular rings formed by the right aortic arch are symptomatic while others are not.

A persistent fifth aortic arch in man: a double-lumen aortic arch (presentation of a new case and review of the literature).

Persistent fifth aortic arch manifested as a double-lumen aortic arch (DLAA) is a rare anomaly. We present such a case with transposition of the great arteries, ventricular septal defect (VSD), and pulmonary atresia. Review of the eight previously published cases indicates relatively frequent association of DLAA with preductal coarctation of the aorta. We attempt to explain the coexistence of this lesion with DLAA. We also discuss evidence supporting derivation of the inferior channel of the DLAA from the embryologic fifth aortic arch.

Single versus biplane right and left ventricular volumetry: a cast and clinical study.

True volume (y) and measured volume (x) determined from 23 right and 22 left normal human casts in four biplane angiographic positions and in their eight single-plane components were used to find the correction factor (b) by regression through the origin (y = bx). The correction factors were applied to human studies to assess the validity of the various biplane and single-plane modalities in vivo. The casts studies yield excellent correlations in both right and left biplane methods (right volumetry: 0.555 less than or equal to b less than or equal to 0.708, 0.917 less than or equal to r less than or equal to 0.954, 4.10 less than or equal to SEE less than or equal to 6.01 left volumetry: 0.748 less than or equal to b less than or equal to 0.825, 0.974 less than or equal to r less than or equal to 0.982, 4.81 less than or equal to SEE 5.79). Good results were obtained with single-plane volumetries as well (right volumetry: 0.316 less than or equal to b less than or equal to 0.887, 0.750 less than or equal to r less than or equal to 0.917, 10.75 less than or equal to SEE less than or equal to 18.96; left volumetry: 0.728 less than or equal to b less than or equal to 0.881, 0.897 less than or equal to r less than or equal to 0.976 5.73 less than or equal to SEE less than or equal to 11.97). The correction factors for the single-plane studies depend much more strongly on the spatial position relative to the radiographic system, particularly in the case of the right ventricular volumes. Thus, the application of the appropriate correction factors is mandatory. The human studies (141 left and 60 right volumetric studies in various single-plane and biplane projections) showed a larger scatter of single-plane values, more pronounced for the right ventricle. In certain disease conditions, single plane volumetric studies using cast-derived correction factors cannot be used to obtain meaningful results. Correction factors for the following single or biplane mode volumetry are presented for the first time: biplane hepatoclavicular view (right and left ventricle), biplane long axial oblique view (right ventricle), and their single-plane components; lateral and 60 degree Left Anterior Oblique (LAO) single plane for the left-sided measurements, Postero-Anterior (PA), lateral, and 60 degree LAO for the single-plane right-sided calculations.

Intrarenal aneurysm of the renal artery in children.

Two children with hypertension had intrarenal aneurysms in the renal artery. In both children, renovascular hypertension was documented by renal vein renin assay showing elevated renin secretion from the involved kidney and suppression of renin secretion from the contralateral kidney. Transcatheter embolization of a segmental artery cured the hypertension in one case. A nephrectomy performed in the other case, because of multiple intrarenal aneurysms, was curative. Intrarenal renal artery aneurysms are an uncommon cause of renovascular hypertension in children. The aneurysms may be mycotic or congenital in origin, or secondary to diffuse vasculitis. Although spontaneous resolution of the aneurysms may occur when due to vasculitis, treatment of most aneurysms is usually necessary. Transcatheter embolization of solitary aneurysms is an attractive alternative to partial nephrectomy, since it allows maximal preservation of renal parenchyma with minimal morbidity.

Manipulation of vena cava filters. Locked-catheter technique.

A method is described for the rapid and easy manipulation of a Kimray-Greenfield vena cava filter beyond an obstructing eustachian valve.

Calcified thrombus of the inferior vena cava in transposition of the great vessels.

Calcified thrombus of the inferior vena cava (IVC) in children is an entity usually not associated with significant complications. The possibility of pulmonary embolism from the soft thrombus, however, has been suggested but never reported. We give an account of a child with transposition of the great vessels who suffered embolization from a calcified thrombus in the IVC that entered the systemic circulation.

MR imaging of the central pulmonary arterial tree in conotruncal malformation.

Successful MR imaging of the central pulmonary arterial tree was performed in four cases of conotruncal malformation and in one case of pulmonary arterial banding. Angiography performed near the time of MR imaging in three cases and 15 years earlier in two other cases did not visualize the central pulmonary arterial tree. Multiplanar imaging was necessary to fully visualize the anatomy of complex congenital defects of the pulmonary arterial tree; the choice of imaging plane varied depending on the portion of the pulmonary artery to be evaluated.