Progressive interatrial block associated with atrial fibrillation in a patient with hypertrophic cardiomyopathy.

Progressive interatrial block is a clinically significant condition that has previously been reported in various patient populations. It is a manifestation of progressive fibrosis affecting the Bachmann region. This report presents a case of progressive interatrial block associated with atrial fibrillation in the context of hypertrophic cardiomyopathy.

Massive J-waves in the context of intracranial hemorrhage.

Transient ST-segment elevation may be caused by conditions other than myocardial ischemia, among them intracranial hemorrhage. Recognition of the underlying etiology of these ST-segment changes is key because of the vastly different therapies used to treat them. We describe the case of a patient with massive transient J-waves and ST-segment elevation in the context of an intracranial hemorrhage.

Current State of Point-of-care Ultrasound Usage in Canadian Emergency Departments.

Background Point-of-care ultrasound (POCUS) has many applications in emergency medicine, which have been proven to improve patient outcomes. Training programs and well-established guidelines for its use are available, but Canadian adoption rates and attitudes toward this technology have not been recently assessed. Objectives This study aimed to provide a national assessment of the current use of POCUS in Canadian emergency departments (ED) including patterns of use, attitudes towards its role, descriptors of training experience, as well as barriers to increased utilization. Methods An electronic survey was sent to physician members of the Canadian Association of Emergency Physicians. The survey included questions related to demographics, attitudes towards POCUS, POCUS utilization, and barriers to POCUS use. Responses were statistically analyzed to identify significant associations. Results Responses demonstrated a strong association between POCUS training and amount of POCUS usage. Neither hospital type nor community type was associated with the degree of POCUS usage. POCUS was most widely adopted for Canadian Point of Care Ultrasound Society (CPOCUS) core applications and has increased since the last national survey. The most commonly reported barrier to increased POCUS adoption was the lack of training. Most physicians have formal POCUS training in core applications, and approximately one third have advanced training. Conclusions POCUS training and utilization appear to have increased since the last national assessment. This provides a foundation for future POCUS research.

Food deprivation and prior anoxic coma have opposite effects on the activity of a visual interneuron in the locust.

We compared how different metabolic stressors, anoxic coma and food deprivation, affected signaling in neural tissue. We used the locust's Descending Contralateral Movement Detector (DCMD) interneuron because its large axon, high firing frequencies, and rapid conduction velocity make it energetically expensive. We exposed locusts to a 30min anoxic coma or 1day of food deprivation and found contrasting effects on signaling within the axon. After a prior anoxic coma, the DCMD fired fewer high-frequency (>200Hz) action potentials (APs) (Control: 12.4±1.6; Coma: 6.3±0.9) with a reduction in axonal conduction velocity (CV) at all frequencies (∼4-8%) when presented with a standard looming visual stimulus. Prior anoxic coma was also associated with a loss of supernormal conduction by reducing both the number of supernormal APs and the firing frequency with the highest CV. Initially, food deprivation caused a significant increase in the number of low- and high-frequency APs with no differences observed in CV. After controlling for isolation, food deprivation resulted in an increase in high-frequency APs (>200Hz: Control: 17.1±1.7; Food-deprived: 19.9±1.3) and an increase in relative conduction velocity for frequencies >150Hz (∼2%). Action potentials of food-deprived animals had a smaller half-width (Control: 0.45±0.02ms; Food-deprived: 0.40±0.01ms) and decay time (Control: 0.62±0.03ms; Food-deprived: 0.54±0.02ms). Our data indicate that the effects of metabolic stress on neural signaling can be stressor-dependent.