Enhanced external counterpulsation improves cerebral blood flow following cardiopulmonary resuscitation.

BACKGROUND: To investigate the therapeutic value of enhanced external counterpulsation (EECP) on recovery of cerebral blood flow following cardiac arrest (CA) and successful resumption of spontaneous circulation (ROSC) by cardiopulmonary resuscitation. METHODS: CA models were conducted using beagle dogs induced by alternating current. After successful ROSC by cardiopulmonary resuscitation, 16 dogs were randomly divided into the EECP and control group (n = 8 per group). Dogs underwent dynamic contrast-enhanced and diffusion-weighted magnetic resonance imaging at baseline prior to CA and during the 3 days following ROSC. Mean blood pressure, right common carotid artery blood flow, intracranial microcirculation and blood lactate levels were measured. Neurological outcome was assessed by the neurologic deficit score. Hematoxylin-eosin staining and transmission electron microscopy were performed for morphology and microconstruction of the cerebral cortex. RESULTS: The EECP group exhibited a significant elevation in right common carotid artery blood flow, intracranial microcirculation and a substantial decrease in blood lactate levels relative to the control group. Relative cerebral blood flow and volume were higher in the EECP group during the 3 days. Apparent diffusion coefficients were significantly higher in the EECP group on the first and third days. After ROSC, the neurologic deficit score was significantly higher in the control group compared to those in the EECP group during the three days of experiment. The cell swelling of neurons and increase of mitochondrial mass were more pronounced in the control group. CONCLUSION: EECP is beneficial for recovery of cerebral blood flow and attenuation of ischemic cerebral edema following CA and successful ROSC.

Premenstrual dysphoric disorder and prefrontal reactivity during anticipation of emotional stimuli.

Premenstrual disorder (PMDD) affects around 5% of women in childbearing ages. An increased sensitivity in emotion processing areas of the brain to variations in ovarian steroid levels has been suggested as part of the pathophysiology in PMDD, but prior neuroimaging studies of emotion processing are yet inconclusive. Previous behavioral studies of women with PMDD have, however, reported enhanced luteal phase startle responsivity during emotional anticipation. Here we used functional magnetic resonance imaging (fMRI) to investigate central neural circuitry activity during anticipation of, and exposure to, emotional stimuli across the menstrual cycle in women with and without PMDD. As compared to healthy controls, women with PMDD displayed significantly enhanced reactivity in the prefrontal cortex during anticipation of, but not exposure to, negative emotional stimuli during the luteal phase. In PMDD patients, BOLD reactivity during anticipation or viewing of negative emotional stimuli was not dependent on absolute levels of estradiol or progesterone. However, progesterone levels were positively correlated with emotion-induced reactivity in the dorsolateral prefrontal cortex to positive emotional stimuli. These findings suggest that cortical emotional circuitry reactivity during anticipation is altered in PMDD during the luteal phase, which might be part of the pathophysiology behind the emotional symptoms or lack of emotional control reported by women with PMDD.