Fig. 5
Hazard ratios for LAVi as a continuous variable. Restricted cubic spline model of hazard ratios for left atrial volume indexed. The 3 curves represent the hazard ratio and the upper and lower bounds of the 95% confidence interval at any given LAVi. The transition point of the lower bound of the 95% confidence interval occurs at 52 ml/m2 which also correspond to the upper limit of normal LA size derived by standard deviations. Hazard ratios after 73 ml/m2 tend to even out as the gradient of the curve plateaus