Soft thrombus formation in radiofrequency catheter ablation.

During RF catheter ablation, local temperature elevation can result in coagulum formation on the ablation electrode, resulting in impedance rise. A recent study has also demonstrated the formation of a so-called soft thrombus during experimental ablations. This deposit poorly adhered to the catheter tip and did not cause an impedance rise.

[Evolution of the astroglial reaction in the pyramidal pathway after injury of the rat motor cortex].

Investigation of astrocytes in the pyramidal tract of the rat 2 to 100 days after a lesion of the motor cortex indicates that the glial reaction, with increase in size of astrocytes and in affinity for Cajal's gold-sublimate, begins at the lesion and extends to the distal segments of the spinal cord. But this reaction recedes and disappears in lumbar and dorsal cord about 70 days after the operation. It persists in the cervical cord and in the brain.