Surgical Thrombectomy for Pulmonary Embolism: Updated Performance Rates and Outcomes

Treatments for pulmonary embolism are numerous and often complex. Current data on surgical thrombectomy are important but are not readily available. We studied the National Inpatient Sample to evaluate trends in the performance rates and outcomes of surgical thrombectomy in the United States from 2003 through 2014. We think that our findings have meaningful application to the triage and risk stratification of patients who have hemodynamically significant pulmonary embolism

Preconditioning Induces Sustained Neuroprotection by Down Regulation of AMPK

Abstract Background and Purpose—Ischemic preconditioning (IPC) induces endogenous neuroprotection from a subsequent ischemic injury. IPC involves down-regulation of metabolic pathways. As Adenosine 5′-monophosphate-activated protein kinase (AMPK) is a critical sensor of energy balance and plays a major role in cellular metabolism, its role in IPC was investigated. Methods—A brief 3 minute middle cerebral artery occlusion (MCAO) was employed to induce IPC in male mice 72 hours prior to 90 minute MCAO. Levels of AMPK and pAMPK, the active form of the kinase, were assessed after IPC. A pharmacological activator or inhibitor of AMPK was utilized to determine the dependence of IPC on AMPK signaling. Additionally, AMPK-α2 null mice were subjected to IPC and subsequent infarct damage was assessed. Results—IPC induced neuroprotection, enhanced HSP70 and improved behavioral outcomes. These beneficial effects occurred in parallel with a significant inhibition of pAMPK protein expression. Although both pharmacological inhibition of AMPK or IPC led to neuroprotection, IPC offered no additional protective effects when co-administered with an AMPK inhibitor. Moreover, pharmacological activation of AMPK with Metformin abolished the neuroprotective effects of IPC. AMPK-α2 null mice that lack the catalytic isoform of AMPK failed to demonstrate a preconditioning response. Conclusions—Regulation of AMPK plays an important role in IPC mediated neuroprotection. AMPK may be a potential therapeutic target for the treatment of cerebral ischemia

NF-κB Contributes to the Detrimental Effects of Social Isolation After Experimental Stroke

Social isolation (SI) is increasingly recognized as a risk factor for stroke. Individuals with lack of social support systems have an increased incidence of stroke, poorer recovery, and greater functional decline after injury compared to individuals with social support. Attesting to the importance of social factors in stroke outcome is that these same effects can be reproducibly demonstrated in animals; social interaction improves behavioral deficits and reduces damage after experimental stroke, whereas SI enhances injury. The mechanism by which SI exacerbates injury is unclear. We investigated the role of nuclear factor-kappaB (NF-κB) signaling in male mice that were pair housed (PH) with an ovariectomized female prior to random assignment into continued PH or SI for 7 days prior to middle cerebral artery occlusion. The effects of SI on infarct volume and functional recovery were assessed at 72 h post-stroke. Nuclear NF-κB levels and activity were assessed by Western blot and transcriptional assays. SI significantly exacerbated infarct size in both male and female mice compared to PH mice. SI mice had delayed functional recovery compared to PH mice. An elevation of systemic IL-6 levels, increased nuclear NF-κB transcriptional activity, and enhanced nuclear translocation of NF-κB was seen in SI stroke animals. Interference with NF-κB signaling using either a pharmacological inhibitor or genetically engineered NF-κB p50 knockout mice abolished the detrimental effects of SI on both infarct size and functional recovery. This suggests that NF-κB mediates the detrimental effects of SI