Figure 5.

Electron microscopy images of goat left atrial myocardium tissue to identify structural changes

Qualitative electron microscopy (EM) on goat left atrial myocardium tissue samples in sinus rhythm (sham, A and C) and after prolonged sustained atrial fibrillation (B, D, E and F). Panel A shows sarcomeres (S) regularly spaced and surrounded by mitochondria. Glycogen (GL), lysosomes (Ly) and numerous irregular shaped mitochondria observed in atrial fibrillation sample (B). We observe many irregular shaped mitochondria dispersed in myolytic areas, autophagic vacuoles (red arrows) and lysosomes (Ly) in (D). Electron micrographs highlighting increased number of endocytic vesicles and vacuoles including endosomes, autophagosomes, lysosomes in atrial fibrillation samples (E and F), indicated by star symbols). (F) is a higher resolution image of the marked square area in Panel E. Samples for EM were collected from N = 3 for AF and N = 3 for Sinus rhythm control animals.