Quantitative coronary analysis in the Nordic Bifurcation studies.

Quantitative coronary analysis (QCA) of bifurcation lesions in the Nordic Bifurcation studies was performed using software dedicated to bifurcating vessels. By now, pre-PCI, post-PCI and 8-month follow-up angiograms of 957 patients have been analyzed in the first three Nordic Bifurcation studies. Large scale clinical studies with specific areas of interest require QCA software with high intra- and inter observer reproducibility, an efficient workflow, flexible features of analysis, a detailed output, and facilities for data export. Recently, a dedicated second generation 2D QCA bifurcation software became commercially available. We used this new software in the third Nordic Bifurcation study for efficient and tailored analysis. Despite widespread automation of the analysis process and experienced observers, an elaborate standard operating procedure is still essential for standardized high quality QCA analysis of bifurcation lesions.