Incomplete endothelialization of left atrial appendage occlusion device 10 months after implantation.

We describe the case of a 74-year-old man with Rendu Osler Weber syndrome affected by permanent atrial fibrillation, who underwent percutaneous placement of a 24-mm Watchman left atrial appendage system. After anticoagulation therapy dismissal, he had a transient ischemic attack (TIA). Therefore he underwent surgical removal of the device, ablation of atrial fibrillation with Maze IV procedure and biatrial reduction. Very interestingly, no significant endothelialization of the device was observed 10 months after implantation. In conclusion, this case is important because, to our knowledge, it is the first finding of Watchman device with lack of endothelialization.

Papillary fibroelastoma of the tricuspid anterior leaflet.

The case of a 50-year-old woman with an occasional diagnosis of cardiac tumor of the tricuspid valve is reported. At surgery, a single 2 cm x 2 cm polypoid gelatinous neoplasm infiltrating the anterior leaflet of the valve was resected and a tricuspid valve reconstruction along with annuloplasty was accomplished. The postoperative period was uneventful. A diagnosis of papillary fibroelastoma was made at pathology. This neoplasm, which represents a rare pathological entity, is more frequently localized on the mitral valve and usually stays asymptomatic for a long time. Only a few cases involving the tricuspid and pulmonary valves have been reported. Indication for surgery is related to a certain incidence of pulmonary embolism. Surgical removal of papillary fibroelastoma is a low-risk and definitive operation, as only one case of recurrence of the tumor has been reported so far in the literature.

Temporal prediction of touch instant during observation of human and robot grasping.

The aim of the present work was to test the ability to predict the instant at which a grasping hand touches an object. Our hypothesis was that, because of the activation of the mirror-neuron system, the same predictive process necessary for action execution should be active during observation. Experimental evidence indicates, however, that not only observed actions but also observed objects automatically activate observer's motor repertoire. What happens, therefore, if the observed action is different from the one automatically evoked by the vision of the object? To answer this question we presented subjects with two different grasping actions: the one most suitable for the presented object and a less appropriate one. Subjects were required to detect the instant at which the demonstrator's hand touched the object. In a further condition, subjects were required to detect the outcome of an action performed by a robotic arm moving with constant kinematics. Results showed that while in the case of robot grasping subjects responded before the touch instant, in the case of human grasping the response followed the touch instant, but occurred much earlier than simple reaction times. This demonstrates that subjects were able to predict the outcome of the seen action. The predictive capability was specifically enhanced during observation of the "suitable" grasping. We interpret these results as an indication of the synergic contribution of both object-related (canonical) and action-related (mirror) neurons during observation of actions directed towards graspable objects.