Background: Coronary computed tomography angiography (CTA) has high diagnostic accuracy in ruling out significant stenosis of coronary arteries. The additional use of CTA- derived FFR further enhances diagnostic utility of coronary CTA. Some of the patients interrogated non-invasively have diseased coronary arteries and undergo further diagnostic testing, including invasive coronary angiography (ICA). Patients with one vessel disease may benefit from invasive interrogation limited to the diseased vessel only.

Aims: In 100 patients, we analysed the impact of a “diseased-vessel-only”, selective invasive diagnostic approach in patients undergoing ICA following coronary CTA (and CT-FFR) as compared to the traditional, “full ICA” approach. Our aim was to compare contrast volume and radiation dose used during ICA in both scenarios, seeking potential benefit for the patient in reducing those values by “diseased-vessel-only” approach.

Results: Sensitivity, specificity, positive predictive value and negative predictive value of CTA in prediction of subsequent revascularization were 96%, 75%, 51% and 99%, respectively, and for CT-FFR 90%, 90%, 69% and 97%, respectively. Using CTA as a method to guide ICA would reduce contrast volume and estimated radiation dose (ED), by 35% and 42.0% respectively (P <0.0001 for both). Taking into consideration CT-FFR results, contrast volume would be reduced by 57% and ED by 69% (P <0.0001 for both).

Conclusion: These real-world data support the concept that vessels with <50% diameter stenosis in QCT and hemodynamically insignificant in CTA-derived FFR may be skipped during ICA. Such approach would result in substantial reductions in contrast media volume used, as well as patient’s exposure to radiation during during ICA, while not leading to missed diagnoses.