Comparison of normalized signal-time curves of all 7 patients in the left atrial appendage. LAA signal-time curves behave in two patterns: No discernible peaks can be seen in normalized signal-time curves in patients with sufficient LAA occlusion and peaks of at least 200% compared to normalized baseline can be seen in those without sufficient coverage of the transcatheter occlusion of the LAA. All signal-time curves start with the second heartbeat which was used for normalization of the signal-time curves (the first image was not used due to incomplete saturation). Variations in the erratic signal-time curve (green solid line with dot symbols) likely represents partial volume effects due to suboptimal breath holding or arrhythmia (atrial fibrillation). The solid curve in the right panel with two positive peaks in the early part of the signal time curve are likely due to such a partial volume effect, as the maximal possible region of interest which could be drawn consisted of only 12 pixels. The differences in magnitude of the peak signal could be caused by individual contrast geometry variations."