Abstract Background Little is known about the hemodynamic interaction between coronary artery stenoses in multivessel disease. Using serial fractional flow reserve (FFR) measurements, the impact of coronary revascularization on remote lesions in parallel vessels was analyzed. This subanalysis aimed to identify characteristics of relevant hemodynamic changes in these remote lesions following revascularization of the index vessel. Methods This is a subanalysis of the prospective, multicenter ABC-FFR trial. The study enrolled patients who were scheduled for PCI of at least one index stenosis who had at least one further stenosis in a parallel vessel. FFR was measured for the parallel lesions before and after PCI of the index lesion. The adjusted median difference was estimated using the Hodges-Lehmann approach with 95% confidence intervals (CI). Results A total of 160 patients (21% female, median age 70 years) with 170 parallel lesions were analyzed. Following PCI of the index lesion, FFR of the parallel lesions decreased modestly but significantly (adjusted median difference -0.01, 95% CI -0.02–0.00, p0.001). Subgroup analyses demonstrated this adjusted median decrease in FFR was more pronounced in remote lesions that were hemodynamically relevant or angiographically severe (Figure). A significantly greater decrease in FFR for the remote lesion following index vessel PCI was observed in remote lesions with an FFR value ≤0.80 (p0.001) and in those with a diameter stenosis degree ≥70% (p=0.008). Likewise, regression analyses (Table) confirmed that the changes in FFR was greater with increasing hemodynamic relevance of the remote lesion (β coefficient 0.116, 95% CI 0.074–0.158, p0.001). This relationship also applied, though to a less significant extent, to its angiographically estimated diameter stenosis (p=0.005). Similar findings were observed for non-hyperemic pressure indices. Conclusions PCI of an index stenosis induces small but measurable reductions in pressure indices of remote, parallel lesions, suggesting a subtle yet significant hemodynamic interplay between parallel lesions. The magnitude of this interaction increases with greater hemodynamic relevance and angiographic severity of the remote lesion.For image description, please refer to the figure legend and surrounding text. For image description, please refer to the figure legend and surrounding text.
Altstidl et al. (Sun,) studied this question.