Comparative Diagnostic Performance and Clinical Effectiveness of Intraoperative Quality Control Modalities in Coronary Revascularization: a Systematic Review and Aggregate Comparative Analysis of Real-World Evidence

Intraoperative graft assessment during coronary artery bypass grafting (CABG) aims to identify technical anastomotic defects before chest closure. Transit-time flow measurement (TTFM) and indocyanine green (ICG) fluorescence imaging represent complementary intraoperative assessment modalities, yet their comparative diagnostic performance against angiographic reference standards remains incompletely defined. PubMed, Scopus, Web of Science Core Collection, and CENTRAL were searched from January 2000 to February 2026 using terms for CABG, ICG, and TTFM; duplicate screening yielded κ = 0.86–0.91. Eligible studies evaluated ICG and/or TTFM against invasive coronary angiography or computed tomography coronary angiography. Methodological quality was appraised using QUADAS-2 for diagnostic cohorts and the Newcastle-Ottawa Scale (NOS) for clinical-utility cohorts. Because only three directly comparable cohorts provided sufficiently reliable paired 2×2 data, formal bivariate random-effects meta-analysis was not performed. Verified 2×2 contingency data were summarised descriptively with exact Clopper–Pearson 95% confidence intervals. Clinical-utility evidence was synthesised narratively. Eighteen unique primary clinical studies were included. Three studies (Desai et al., 2006; Yamamoto et al., 2015; Hatada et al., 2011), comprising 293 paired bypass grafts, provided directly comparable quantitative evidence. ICG demonstrated an aggregate descriptive sensitivity of 76.0% (95% CI, 54.9%–90.6%) and specificity of 99.3% (95% CI, 97.3%–99.9%). TTFM/flowmetry demonstrated aggregate sensitivity of 24.0% (95% CI, 9.4%–45.1%) and specificity of 96.3% (95% CI, 93.2%–98.2%). Formal between-modality P values were not calculated. The aggregate flowmetry estimate includes one cohort using experimental FFT-based waveform analysis (Hatada et al., 2011) and should be interpreted with caution. NOS assessment of six Tier 3 clinical-utility studies yielded scores of 5–9/9; no study provided a complete two-arm comparison with non-zero revision events in both arms, precluding pooled effect estimation. ICG fluorescence imaging showed higher descriptive sensitivity than TTFM/flowmetry for detecting structural graft abnormalities. A complementary approach combining quantitative flow assessment with selective fluorescence imaging may be considered in appropriately selected situations. Prospective multicenter studies are required before definitive recommendations can be made.