Click on image to view larger version.

Figure 5 Histologic findings of the identical case as in Figure 4. (Top) (low magnification), Transmural coagulation necrosis (N) is detected near the junction (curved portion) between the (LA) and the inferior pulmonary vein (PV) trunk. Atrial myocardial extension (Ex) (about 9 mm in length) spreads into the PV almost entirely and reaches near the right end of the panel. Fa = fat tissue; Ao = aorta. (Middle) (intermediate magnification), coagulation necrosis (N) in the LA myocardium and contraction band necrosis (CBN) in the proximal portion of the atrial myocardial extension into the PV. (Bottom) (high magnification), Coagulation necrosis (N) of muscle fibers located within the ablated LA. All specimens are in Azan stain.