The Dynamic Interplay between Loss of Semantic Memory and Semantic Learning Capacity: Insight from Neologisms Learning in Semantic Variant Primary Progressive Aphasia.

Semantic Variant of Primary Progressive Aphasia (svPPA) has often been considered as a loss of knowledge stored in semantic memory, but might also be due to a general disruption of mechanisms allowing the acquisition, storage, and retrieval of semantic memories. In order to assess any parallelism in svPPA patients between loss of semantic knowledge and inability to acquire new semantic information, we administered a battery of semantic learning tasks to healthy individuals and svPPA patients, where they were requested to learn new conceptual representations and new word forms, and to associate the former with the latter. A strong relation was found between loss of semantic knowledge and disruption of semantic learning: (a) patients with severe svPPA had the lowest scores in the semantic learning tasks; (b) significant correlations were found between scores obtained in semantic learning tasks and scores obtained in semantic memory disorders in svPPA patients.

Allochiria for spatial landmarks as the presenting feature of posterior cortical atrophy.

Allochiria refers to the mislocation of stimuli to the corresponding position on the opposite side of the body or hemispace. It is most often, although not exclusively, reported in the tactile modality and typically in association with unilateral neglect. We describe a patient presenting with a 2-year history of topographical disorientation without other cognitive complaints. We conducted a systematic exploration of his topographical problems to identify their cognitive substrate. Standard neuropsychological examination revealed no abnormalities. Notably, he performed well on perceptual, spatial, and constructional tasks. No signs of neglect were elicited. A tailored battery of tests was administered, involving road maps and landmarks, and designed to replicate the situations in which he experienced symptoms. The experimental tests showed no evidence of topographical agnosia or amnesia for landmarks and their spatial relationships and no hemispatial neglect. Nevertheless, the patient exhibited a systematic tendency to translocate topographical landmarks sited on the left to the right side. The phenomenon, consistent with representational allochiria, occurred exclusively for topographical landmarks, and was present along both personally familiar and new learned routes. Over the next two years more widespread visuoperceptual and spatial deficits emerged, with Balint and Gerstmann syndromes. Functional imaging revealed hypoperfusion of the occipito-parietal regions and amyloid PET the presence of amyloid plaques. A diagnosis was made of posterior cortical atrophy, the visual variant of Alzheimer's Disease. To our knowledge this is the first case of topographical disorientation presenting with selective representational allochiria and the first report of allochiria as an early sign of posterior cortical atrophy. The case sheds light on the cognitive basis of allochiria and on a puzzling clinical presentation of neurodegenerative brain disease.

Aortic expansion rate in patients with dilated post-stenotic ascending aorta submitted only to aortic valve replacement long-term follow-up.

OBJECTIVES: This study was conceived to describe the evolution of aortic dimensions in patients with moderate post-stenotic ascending aorta dilation (50 to 59 mm) submitted to aortic valve replacement (AVR) alone. BACKGROUND: The appropriate treatment of post-stenotic ascending aorta dilation has been poorly investigated. METHODS: Ninety-three patients affected by severe isolated calcific aortic valve stenosis in the tricuspid aortic valve accompanied by moderate dilation of the ascending aorta (50 to 59 mm) were submitted to AVR only. All patients were followed for a mean of 14.7 ± 4.8 years by means of periodic clinical evaluations and echocardiography and tomography scans of the thorax. RESULTS: Operative mortality was 1.0% (1 patient). During the follow-up, 16 patients died and 2 had to be reoperated for valve dysfunction. No patients experienced acute aortic events (rupture, dissection, pseudoaneurysm), and no patient had to be reoperated on the aorta. There was not a substantial increase in aortic dimensions: mean aortic diameter was 57 ± 11 mm at the end of the follow-up versus 56 ± 02 mm pre-operatively (p = NS). The mean ascending aorta expansion rate was 0.3 ± 0.2 mm/year. CONCLUSION: In the absence of connective tissue disorders, AVR alone is sufficient to prevent further aortic expansion in patients with moderate post-stenotic dilation of the ascending aorta. Aortic replacement can probably be reserved for patients with a long life expectancy.

Survival after aortic valve replacement for aortic stenosis: does left ventricular mass regression have a clinical correlate?

AIM: The effects of post-operative left ventricular mass regression (LVMR) on clinical outcome after aortic valve surgery remains to be established. This study was intended to establish the impact of patient characteristics on post-operative survival in patients referred for aortic valve replacement (AVR), with particular regard to LVMR. METHODS AND RESULTS: Two hundred and sixty consecutive cases submitted to aortic valve replacement for valvular stenosis were prospectively followed for a mean of 28+/-9 months. Baseline, characteristics and extent of LVMR were tested for association with survival by uni- and multivariable analysis. Ten deaths occurred during hospital stay and 52 during out-of-hospital follow-up. Mean left ventricular mass decreased from 190+/-43 to 158+/-70 g/m2 (P<0.001). Older age, advanced functional class, hypertension, reduced left ventricle ejection fraction, and high pre-operative left ventricular mass index were associated with reduced survival. Overall the extent of LVMR did not influence the clinical results, while only early (<6 months) LVMR was weakly associated with mid-term outcome. CONCLUSION: Survival after aortic valve surgery is mainly determined by the pre-operative functional cardiac and systemic status. The extent of LVMR does not correlate with clinical outcome, whereas aggressive treatment of hypertension may improve post-operative survival.

High risk coronary artery bypass patient: incidence, surgical strategies, and results.

BACKGROUND: To describe our experience in the treatment of high risk coronary artery bypass patients and compare patients assigned to on-pump or off-pump surgery. METHODS: During a 42-month period 306 high risk (Euroscore > 5) coronary artery bypass patients were consecutively treated at our institution. On the basis of the coronary anatomy and possibility of achieving a complete revascularization, 197 patients were assigned to off-pump and 109 to on-pump operation. Overall mortality was 6.2% (19 of 306 patients). RESULTS: Although patients treated off-pump had a better cardiac status, no clinical advantages related to the avoidance of cardiopulmonary bypass were found in the overall population. Off-pump patients had more early and late cardiac complications, whereas patients operated on-pump exhibited an higher incidence of postoperative systemic organ dysfunction. Off-pump surgery improved in-hospital outcome only in the subset of patients at highest risk. CONCLUSIONS: Avoidance of cardiopulmonary bypass does not confer significant clinical advantages in all high risk coronary patients; instead, there are particular subsets of patients in whom beating heart surgery can be particularly indicated and others for whom on-pump revascularization appears a better solution. Adaptation of the operation to the single patient is probably the way to improve outcome.

Effect of surgical revascularization of a right coronary artery tributary of an infarcted nonischemic territory on the outcome of patients with three-vessel disease: a prospective randomized trial.

BACKGROUND: We evaluated the in-hospital and long-term effects of surgical grafting of a dominant graftable right coronary artery tributary of an infarcted nonischemic territory in patients with triple-vessel disease who were undergoing coronary artery bypass grafting. METHODS: Of 303 consecutive patients undergoing coronary artery bypass grafting with 3-vessel coronary disease and a dominant right coronary artery tributary of an infarcted nonischemic territory, 154 were randomized to right coronary artery revascularization and 149 to no right coronary artery grafting. In all cases, standard on-pump surgical myocardial revascularization was performed. RESULTS: Overall hospital mortality was 2 of 154 versus 1 of 149 (P =.97); no difference in in-hospital outcome was observed between the 2 groups. At follow-up, cardiac event-free survival was 84 of 152 in the right coronary artery grafting series and 62 of 148 in the non-right coronary artery grafting group (P =.20). However, when the analysis was limited to surviving patients without new scintigraphic evidence of ischemia (to avoid confounding factors derived from ischemia in the left coronary system or right coronary artery graft malfunction), we found that patients who received a right coronary artery graft had fewer cardiac events, a lower incidence of arrhythmia, and less left ventricular dilatation than did the non-right coronary artery revascularized series. CONCLUSIONS: Surgical grafting of a right coronary artery tributary of an infarcted nonischemic territory in patients with 3-vessel coronary artery disease submitted to coronary artery bypass grafting improved late electric stability, ventricular geometry, and event-free survival but did not affect in-hospital or 10-year survival.

Early and late arrhythmias in patients in preoperative sinus rhythm submitted to mitral valve surgery through the superior septal approach.

BACKGROUND: It has been hypothesized that the use of the superior septal approach to the mitral valve can lead to postoperative loss of sinus rhythm. This study was undertaken to evaluate the early and mid-term alterations of the cardiac rhythm in patients with preoperative sinus rhythm (SR) submitted to mitral valve surgery through the superior septal approach. METHODS: Seventy-five cases in preoperative SR submitted to primary isolated mitral valve surgery through the superior septal approach constitute the study population. All patients underwent 12-lead electrocardiography on admission, every day after surgery until discharge and every year during the follow-up period. RESULTS: On admission in the intensive care unit, 46 cases maintained their preoperative rhythm, whereas 18 developed a junctional rhythm (JR) and 7 had a first- or second-degree atrio-ventricular block (AVB). Four cases arrived in the unit in atrial fibrillation (AF). On the first postoperative day, these proportions were substantially unchanged, with the only exception being a slight increase in the number of patients in AF. The day before discharge, only 35 of the 74 surviving cases maintained the preoperative SR, whereas 13 developed AF, 10 were in JR, and 16 were in AVB. During the follow-up period (mean, 26 +/- 14 months), the majority of cases (47/74) regained SR; 11 patients had AVB, 3 were in JR, and the remaining 13 were in AF. CONCLUSIONS: The use of the superior septal approach for mitral valve procedures in patients in preoperative SR is associated with minor, transient cardiac rhythm disturbances.