Feasibility of computed tomography perfusion in patients with chronic total occlusion undergoing percutaneous coronary intervention

We aimed to establish the feasibility and safety of dynamic computed tomography perfusion (CTP) in patients with chronic total occlusion (CTO) undergoing percutaneous coronary intervention (PCI). Ten consecutive CTO patients with preserved left ventricular ejection fraction (≥50%) underwent regadenoson dynamic CTP prior to and at least 3 months after successful CTO recanalization. Quantitative absolute and indexed values of stress myocardial blood flow (MBF) were measured for each myocardial segment, and perfusion defect size was defined by the number of segments with indexed MBF ≤0.78. The control group comprised 10 subjects without ischemia on CTP. Out of 20 CTP studies with 320 segments, 311 segments (97.2%) were interpretable. The dose-length product for CTP was 589.5 ​± ​144.3 mGy cm, and no severe adverse reactions to either regadenoson or contrast were observed. Successful PCI resulted in a significant increase in stress MBF in CTO (101.8 [82.9–127.1] vs. 158.4 [132.6–172] ml/100ml/min, p ​= ​0.004). Overall, there were significant reductions in both CTO and total defect size post-PCI (5 [5–6] vs. 1 [0.3–2] and 6 [5–8.5] vs. 1.5 [1–3.8] segments, both p ​= ​0.002). In segment analysis, the indexed MBF was lowest in the pre-PCI CTO group (0.90 [0.53–1.0]), followed by post-PCI CTO group (0.96 [0.88–1.0]) and the control group (0.98 [0.94–1.0]). Dynamic CTP is feasible and safe, and shows large perfusion defects in patients with CTO. While ischemic burden can be significantly improved after successful CTO PCI, it is still larger as compared with normal myocardium. NCT04465526: The Influence of Coronary Chronic Total Occlusion on Myocardial Perfusion on Computed Tomography (COPACABANA).