Murray law based quantitative flow ratio in imaging vs. angiography guided DK crush stenting for left main and non left main bifurcations

Abstract Background Percutaneous coronary interventions (PCI) for true bifurcation lesions remain technically challenging. Intravascular imaging (IVI) guidance improves outcomes in complex PCI, yet its role in double-kissing (DK)-crush remains unclear. Murray law–based fractional flow reserve (μFR) is a novel, angiography-derived physiological index that enables functional assessment of both the main vessel (MV) and side branch (SB) in bifurcation lesions. Aims This study aimed to evaluate whether IVI guidance reduces adverse events compared with angiography alone in left main (LM) and non-LM true bifurcations treated with DK-crush, and to use μFR to compare procedural results between the two guidance strategies. Methods We retrospectively included all patients treated with DK-crush PCI at our Hospital, Florence (2017–2025). Patients were stratified by lesion site (LM vs. non-LM) and guidance (angiography vs. imaging). The primary endpoint was target bifurcation failure (TBF). Angiograms were analyzed with AngioPlus Core 2.5 software for μFR calculation. Results Among 96 patients (57 LM, 39 non-LM), IVI was used in 74%. In non-LM bifurcations, IVI guidance achieved higher final μFR in MV (0.95 ± 0.04 vs. 0.91 ± 0.04, P = 0.007)(Figure 1, panel A) and SB (0.97 ± 0.02 vs. 0.94 ± 0.05, P = 0.007)(Figure 1, panel B), with lower TBF (0% vs. 17.6%, P = 0.04; log-rank P = 0.005). No significant differences were seen in LM lesions. Final MV μFR independently predicted lower TBF risk (HR 0.01, 95% CI 0.01–0.57, P = 0.042)(Figure 2), and SB μFR 0.96 was associated with fewer TBF in non-LM cases (log-rank P = 0.029). Conclusions In DK-crush PCI for non-LM bifurcations, IVI guidance improves physiological outcomes – reflected by higher post-PCI μFR in both MV and SB – and reduces TBF rates. Post-PCI MV μFR is an independent predictor of TBF.For image description, please refer to the figure legend and surrounding text. For image description, please refer to the figure legend and surrounding text.