Background-Accurate diagnosis of major aortopulmonary collaterals (MAPCAs) and partial anomalous pulmonary venous drainage (PAPVD) in adult patients with congenital heart disease is important but problematic. Threedimensional contrast-enhanced magnetic resonance angiography (MRA) provides a minimally invasive technique to allow detailed studies in a single breath-hold. Methods and Results-We assessed the role of contrast-enhanced 3D MRA in 29 consecutive adult patients with a diagnosis of MAPCAs (nϭ16) or PAPVD (nϭ13) made by echocardiogram, cardiac catheterization, or surgical inspection. MRA was performed with a 3D spoiled gradient-echo technique with intravenous gadolinium-DTPA (0.2 mmol/kg). In both types of pathology, there was excellent correlation between MRA and the cardiac catheterization, echocardiogram, or surgical inspection. Additional information was gained for patients with MAPCAs on confluence and size of pulmonary arteries (nϭ13 had central arteries), pulmonary artery stenosis (nϭ3), aneurysmal dilatation of pulmonary artery (nϭ1), and additional anomalous vascular abnormality (nϭ3). Shunt assessment, where present (9 of 16), showed patency in all cases (100%). For adults with PAPVD, further information was obtained on drainage origin (nϭ11). There were no complications. Conclusions-Contrast-enhanced 3D MRA provides a fast, noninvasive, radiation-free method of accurate and comprehensive diagnosis of MAPCAs and PAPVD in adult patients.

Objective-To clarify the problems in angiographic diagnosis of major coronary arteries crossing the right ventricular outflow tract. Design-Aretrospectivestudywithclinicomorphological correlations to ascertain any aberrant coronary arteries and variations in distribution of the normal right coronary arterial branches. Setting-Tertiary referral centre. Subjects-36 necropsy specimens together with the aortograms and surgical reports from 130 patients with tetralogy of Fallot. Results-A preventricular branch was found in 19% of cases with tetralogy of Fallot, but in none of 13 normal hearts. Aberrant origin of the anterior interventricular coronary artery was found in 14% of the specimens. The combination of "laid back" and straight lateral views, when reviewed retrospectively, identified this anomaly correctly in nine of 16 patients, with these findings confirmed at surgery in seven patients. A major branch initially thought to cross the outflow tract was shown retrospectively to be an infundibular artery in six, with surgical confirmation in four. It was a preventricular branch in another patient. Conclusions-Using the laid back view alone, infundibular and preventricular branches may be mistaken for a major aberrant artery. A combination of laid back and straight lateral views is needed to avoid false positive diagnosis. (Heart 1998;80:174-183) Keywords: angiography; congenital heart defects; tetralogy of Fallot; paediatric cardiologyThe incidence of a major coronary artery crossing the right ventricular outflow tract in tetralogy of Fallot is between 5% and 12%. [1][2][3][4][5][6][7] Such an anomalous vessel is not always detectable intraoperatively. 3 Preoperative recognition of such arteries is therefore crucial in deciding the time and type of operative procedure to be performed. Despite advances in echocardiographic assessment, investigation by angiography is still considered important in evaluating the coronary arterial patterns preoperatively. The sensitivity and specificity of such angiography, however, remains uncertain. Aortography in standard and oblique projections often fails to identify the origins of the coronary arteries and, more importantly, fails to reveal their relation to the right ventricular outflow tract. More recently, the caudo-cranial left anterior oblique (so called "laid back") aortograms have been advocated for identifying abnormal vessels that cross the pulmonary outflow tract.8 9 In reviewing the experience at our hospital over five years, we have found evidence of one false negative and several false positive diagnoses using the laid back view. These patients with false positive angiographic diagnoses were found, at surgery, to have prominent infundibular or preventricular branches of the right coronary artery rather than anomalous origin of the anterior interventricular (anterior descending) branch of the left coronary artery. These diYculties prompted us to reinvestigate the anatomy of the coronary arteries in tetralogy of Fallot, comparing our findings with the vari...

The position of the outlet septum in relationship to the remainder of the muscular subpulmonary infundibulum represents a hallmark of tetralogy of Fallot, permitting its differentiation from Eisenmenger ventricular septal defects and normal hearts.