CCTA-Guided Invasive Coronary Angiography in Patients With CABG: A Multicenter, Randomized Study

BACKGROUND: Coronary computed tomography angiography (CCTA) in patients with post-coronary artery bypass graft (CABG) has a high diagnostic accuracy for visualization of grafts. Invasive coronary angiography (ICA) in patients with CABG is associated with increased procedural time, contrast agent administration, radiation exposure, and complications, compared with non-CABG patients. The aim of this multicenter, randomized controlled trial was to compare the strategy of CCTA-guided ICA versus classic ICA in patients with prior CABG. METHODS: Patients with prior CABG were randomly assigned (1:1 ratio) to have a CCTA before ICA (CCTA-ICA, group A) or not (ICA-only, group B). The primary end point of the study was the total volume (milliliters) of the contrast agent administered. RESULTS: A total of 251 patients were randomized, and 225 were included in analysis; 110 in group A and 115 in group B. The total contrast volume was higher in group A (184.5 [143-255] versus 154 [102-240] mL; P = 0.001). The contrast volume administered during the invasive procedure was lower in group A (101.5 [60-151] versus 154 [102-240]; P<0.001). Total fluoroscopy time was decreased in group A (480 [259-873] versus 594 [360-1080] seconds; P = 0.027), but total effective dose was increased (24.1 [17.7-32] versus 10.8 [5.6-18] mSv; P<0.001). The rate of contrast-induced nephropathy, periprocedural complications, and major adverse cardiac events during 3 to 5 and 30 days did not differ significantly between the 2 groups. CONCLUSIONS: A CCTA-directed ICA strategy for patients with CABG is associated with expedition of the invasive procedure, and less fluoroscopy time, at the cost of higher total contrast volume and effective radiation dose, compared with the classic ICA approach.