Computed tomographic versus catheterization angiography in tetralogy of Fallot

To compare multidetector computed tomographic angiography with the gold standard cardiac catheterization and angiography in tetralogy of Fallot.

In 40 consecutive patients over 5 years of age with tetralogy of Fallot, multidetector computed tomographic angiography and catheterization angiography studies were compared for intracardiac anatomy, pulmonary anatomy and indices, coronaries and collaterals. Safety parameters, relative advantages and limitations were also analyzed.

All catheterization studies required hospitalization whereas all tomographic studies were performed as outpatient procedures. The need for sedation and amount of contrast used were significantly greater in catheterization than in tomographic studies. Complications noted during catheterization were access site complications in 4 patients, cyanotic spells in 2, transient complete heart block requiring temporary pacing in 2, and air embolism in one. No complication was observed during tomographic studies. All tomographic studies were adequate, but 2 catheterization studies were inadequate. Ventricular septal defects, aortic override, level of right ventricular outflow tract obstruction, and pulmonary artery anatomy were equally assessed by both imaging modalities. However, tomographic studies missed additional small muscular ventricular septal defects. There was a linear correlation between tomographic and catheterization studies for pulmonary annulus size, artery sizes, Z-score, and Nakata index. There was complete concordance with respect to side of aortic arch and detection of collaterals. Coronary anatomy was better delineated in tomographic studies.

For preoperative evaluation of tetralogy of Fallot patients, multidetector computed tomographic angiography can be used as a reliable noninvasive alternative to cardiac catheterization angiography.