Perceived and mentally rotated contents are differentially represented in cortical depth of V1

Primary visual cortex (V1) in humans is known to represent both veridically perceived external input and internally-generated contents underlying imagery and mental rotation. However, it is unknown how the brain keeps these contents separate thus avoiding a mixture of the perceived and the imagined which could lead to potentially detrimental consequences. Inspired by neuroanatomical studies showing that feedforward and feedback connections in V1 terminate in different cortical layers, we hypothesized that this anatomical compartmentalization underlies functional segregation of external and internally-generated visual contents, respectively. We used high-resolution layer-specific fMRI to test this hypothesis in a mental rotation task. We found that rotated contents were predominant at outer cortical depth bins (i.e. superficial and deep). At the same time perceived contents were represented stronger at the middle cortical bin. These results identify how through cortical depth compartmentalization V1 functionally segregates rather than confuses external from internally-generated visual contents. These results indicate that feedforward and feedback manifest in distinct subdivisions of the early visual cortex, thereby reflecting a general strategy for implementing multiple cognitive functions within a single brain region

Use of mechanical circulatory support in patients with non-ischaemic cardiogenic shock

Aims Despite its high incidence and mortality risk, there is no evidence-based treatment for non-ischaemic cardiogenic shock (CS). The aim of this study was to evaluate the use of mechanical circulatory support (MCS) for non-ischaemic CS treatment.Methods and results In this multicentre, international, retrospective study, data from 890 patients with non-ischaemic CS, defined as CS due to severe de-novo or acute-on-chronic heart failure with no need for urgent revascularization, treated with or without active MCS, were collected. The association between active MCS use and the primary endpoint of 30-day mortality was assessed in a 1:1 propensity-matched cohort. MCS was used in 386 (43%) patients. Patients treated with MCS presented with more severe CS (37% vs. 23% deteriorating CS, 30% vs. 25% in extremis CS) and had a lower left ventricular ejection fraction at baseline (21% vs. 25%). After matching, 267 patients treated with MCS were compared with 267 patients treated without MCS. In the matched cohort, MCS use was associated with a lower 30-day mortality (hazard ratio 0.76, 95% confidence interval 0.59-0.97). This finding was consistent through all tested subgroups except when CS severity was considered, indicating risk reduction especially in patients with deteriorating CS. However, complications occurred more frequently in patients with MCS; e.g. severe bleeding (16.5% vs. 6.4%) and access-site related ischaemia (6.7% vs. 0%).Conclusion In patients with non-ischaemic CS, MCS use was associated with lower 30-day mortality as compared to medical therapy only, but also with more complications. Randomized trials are needed to validate these findings.[GRAPHICS

Early Impella Support in Postcardiac Arrest Cardiogenic Shock Complicating Acute Myocardial Infarction Improves Short- And Long-Term Survival∗

OBJECTIVES: Early mechanical circulatory support with Impella may improve survival outcomes in the setting of postcardiac arrest cardiogenic shock after out-of-hospital cardiac arrest complicating acute myocardial infarction. However, the optimal timing to initiate mechanical circulatory support in this particular setting remains unclear. Therefore, we aimed to compare survival outcomes of patients supported with Impella 2.5 before percutaneous coronary intervention (pre-PCI) with those supported after percutaneous coronary intervention (post-PCI). DESIGN: Retrospective single-center study between September 2014 and December 2019 admitted to the Cardiac Arrest Center in Marburg, Germany. PATIENTS: Out of 2,105 patients resuscitated from out-of-hospital cardiac arrest due to acute myocardial infarction with postcardiac arrest cardiogenic shock between September 2014 and December 2019 and admitted to our regional cardiac arrest center, 81 consecutive patients receiving Impella 2.5 during admission coronary angiogram were identified. OUTCOMES/MEASUREMENTS: Survival outcomes were compared between those with Impella support pre-PCI to those with support post-PCI. MAIN RESULTS: A total of 81 consecutive patients with infarct-related postcardiac arrest shock supported with Impella 2.5 during admission coronary angiogram were included. All patients were in profound cardiogenic shock requiring catecholamines at admission. Overall survival to discharge and at 6 months was 40.7% and 38.3%, respectively. Patients in the pre-PCI group had a higher survival to discharge and at 6 months as compared to patients of the post-PCI group (54.3% vs 30.4%; p = 0.04 and 51.4% vs 28.2%; p = 0.04, respectively). Furthermore, the patients in the early support group demonstrated a greater functional recovery of the left ventricle and a better restoration of the end-organ function when Impella support was initiated prior to percutaneous coronary intervention. CONCLUSIONS: Our results suggest that the early initiation of mechanical circulatory support with Impella 2.5 prior to percutaneous coronary intervention is associated with improved hospital and 6-month survival in patients with postcardiac arrest cardiogenic shock complicating acute myocardial infarction. © 2021 by the Society of Critical Care Medicine and Wolters Kluwer Health, Inc. All Rights Reserved