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Figure 1 Heart rate and blood pressure changes during the tilt sequences. Changes in heart rate are demonstrated in A and blood pressure in B. The solid line shows data from the HUT+ group and the dashed line for the HUT– group. In the HUT+ group, a statistically significant decrease in blood pressure presaged syncope, which was subsequently followed by a statistical decrease in heart rate. *p = 0.0002, faint vs. mid-tilt (A). *p = 0.0006 mid-tilt vs. early-tilt; #p < 0.0001 for faint vs. mid-tilt (B). HUT = head up tilt.