Pulmonary Vein Measurements:
The following indices were calculated for each of the PVs once the PV maximum diameter (PVmaxD) and minimum diameter (PVminD) were obtained from MPR images on cCT at the level of the ostium: (1) EI=PVmaxD/PVminD,16 (2) OI = 2 x (PVmaxD-PVminD/PVmaxD+PVminD)16and (3) PVA= π x PVmaxD x PVminD. PV EI values between 1.2-1.4 were representative of ovality while <1.2 were circular and > 1.4 considered as flat. For the OI, higher values were more representative of ovality.