Figure 2
From: Impact of arterial load on the agreement between pulse pressure analysis and esophageal Doppler
Trending ability of pulse pressure-derived cardiac output (PPCO) versus esophageal Doppler cardiac output (EDCO) based on polar plot analysis. Concordance analysis based on polar plots for evaluating trending ability of PPCO versus EDCO (agreement in direction and magnitude of change). Exclusion zone was 9.5% (central white circle). The magnitude of polar vector (the distance from the center of polar plot) represents the mean change in cardiac output. The angle of polar vector with the horizontal axis (θ) is the agreement between both methods. Good trending capability was assumed when most of the data lie within ± 30° radial limits of agreement. Conc, concordance rate.