Figure 1.

Analysis of Hemodynamic Data

(Top left) A minimum of 4 alternations between AAI pacing and HBP or BVP were performed for each tested AV delay (therefore, a total of 8 transitions). For each alternation, relative change in SBP was calculated and the mean of the 8 transitions was calculated. (Top right) As more transitions occur, more data points are collected for change in SBP, eventually resulting in 10 values with mean and confidence intervals. Single or few measurements result in highly inaccurate estimates due to variability. (Bottom) A mean and confidence interval are calculated for each AV delay for both HBP (purple) and BVP (orange). An example is shown of quadratic curves fitted to data from multiple transitions at a range of AV delays to produce the peak systolic blood pressure responses. AV = atrioventricular; BP = blood pressure; BVP = biventricular pacing; ECG = electrocardiogram; HBP = His bundle pacing; SBP = systolic blood pressure.