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Figure 1 The time intensity curves of the same patient as in Figure 2 during a contrast-enhanced cardiac magnetic resonance imaging study while performing a Valsalva maneuver. The blue line represents the signal intensity in the right atrium, and the red line denotes the signal increase in the left atrium. The blue line shows its maximal peak earlier than the red line because of the earlier contrast enhancement of right versus left atrium after intravenously administered contrast agent. The black arrow indicates the contrast passage over the patent foramen ovale showing an additional smaller peak before the maximal peak in the left atrium.