Non-invasive hybrid functional and anatomical imaging for guiding revascularization decision-making by the heart team in patients with prior coronary artery bypass grafting

Background: Coronary computed tomography angiography (CCTA) and myocardial perfusion imaging (MPI) are guideline-recommended to assist in clinical decision-making in patients with prior coronary artery bypass grafting (CABG). However, the value of hybrid functional and anatomical information for guiding revascularization decision-making in post-CABG patients with recurrent ischemic symptoms remains unexplored. We compared Heart Team-defined revascularization strategies based on CCTA, MPI and hybrid CCTA/MPI imaging with strategies guided by invasive coronary angiography (ICA). Methods: We included symptomatic patients with prior CABG who underwent CCTA, MPI (single-photon emission computed tomography, positron emission tomography or stress perfusion cardiac magnetic resonance imaging) and ICA. Simulated independent Heart Teams, composed of interventional cardiologists and either an imaging cardiologist or a cardiac radiologist, performed revascularization decision-making based on conventional CCTA, MPI and a hybrid CCTA/MPI strategy (non-invasive Heart Team) or based on ICA (invasive Heart Team). The primary outcome was the Cohen's kappa agreement (κ) between non-invasive and invasive Heart Teams. Results: A total of 115 patients (mean age 73 ± 7 years; 86 % male) were included. Revascularization was recommended in 96 patients (84 %) by CCTA, 92 patients (80 %) by MPI, 80 patients (70 %) by hybrid CCTA/MPI and 76 patients (66 %) by ICA. The agreements were low for CCTA (κ: 0.25 [95 % confidence interval (CI): 0.07 – 0.42]) and MPI (κ: 0.27 [95 % CI: 0.09 – 0.48]) compared to ICA, with only a modest increase when using the hybrid non-invasive imaging strategy (κ: 0.32 [95 % CI: 0.14 – 0.51]). Conclusions: In patients with recurrent ischemic symptoms after CABG, Heart Team revascularization strategies based on conventional CCTA and MPI showed poor agreements with those guided by ICA, with only modest improvement observed when using a hybrid non-invasive imaging approach.