Figure 1.
Flow chart describing the number of patients with T2W and LGE images at each time-point for the entire cohort.
T2W = T2-weighted imaging. LGE = Late gadolinium enhancement. PVI = pulmonary vein isolation. Data from all available studies were used in all analyses.
Figure 2.
A-B) T2W images from a subject imaged pre pulmonary vein isolation (PVI) (A) and 24-hour post PVI (B), used for measuring right superior PV wall thickness, as shown; note the prominent LA wall thickening. C-F) Another subject imaged pre-pulmonary vein isolation (PVI), 24-hour post-PVI, and 30-day post-PVI. C) Pre-PVI T2W image. D) 24-hours post -PVI T2W image shows enhancement where none is observed pre-PVI. Colored insets highlight regions where signal exceeds the edema threshold in C and D. ROIs were placed on the T2W images, as shown in (C, D). E) Axial T2-weighted (T2W) image at the level of the mid left ventricle (LV) with the region of interest (ROI) used for calculating the edema threshold (defined as 1.4 times the mean LV myocardium signal). F) Late gadolinium enhancement (LGE) 30-days post-PVI demonstrating scar. A left lower PV wall ROI, and blood pool ROI are shown. G) Color) Early post-PVI, the T2W image shows enhancement. Regions above the EER threshold (1.4) are highlighted in green. H) 30-day LGE appears to correlate 24-hour T2W. I) By registration of 24-hour T2W and 30-day LGE, the correlation between acute edema and later scar is more easily quantified, using matched ROIs. The blue shell represents the LA cavity segmented from the 30-day LGE images. The segmented edema (orange) is overlaid on the 30-day LGE image.
Figure 3.
16 segment model showing the 4 regions evaluated around each pulmonary vein.
A) Zoomed and cropped slices labeled by region. B) 3D color-coded display, showing 4 regions about each PV, with explicit labeling for the right inferior and left superior PV.
Table 1.
Patient characteristics and MRI findings for patients with post-PVI imaging.
Table 2.
Summary of Results.
Figure 4.
Axial CMR images demonstrating the progression of scar development of a single patient after PVI.
A) Pre-PVI LGE scan shows no baseline scar. B) 24-hour post PVI T2W image showing areas of edema, highlighted in green, which had an EER>1.4. Inset shows original image. C) 24-hour LGE. D) 30-day post PVI LGE showing enhancement in the pulmonary veins which corresponded to 24-hour edema location. Note the less intense enhancement pattern of 24-hour LGE compared to 30-day LGE, with some enhancement not visible at 24-hours and dark “no-reflow “regions both early and late after PVI (yellow arrows).
Figure 5.
Linear correlations between volumes of LGE enhancement at 30 days, and volumes measured at 24-hours.
A) 24-hour LGE vs. 30-day LGE (R = 0.76, p = 0.09). B) 24-hour T2W vs. 30-day LGE volume (R = 0.74, p = 0.04). All volumes of edema/injury were normalized by the patient’s LA volume.