The first part of the ECG shows a wide QRS tachycardia with a right bundle branch block (RBBB) morphology, an inferior axis and a heart rate of 240 bpm (tachycardia cycle length (TCL) of 250 ms). The middle part shows a narrow QRS tachycardia with an intermediate axis and the same heart rate of 240 bpm (TCL 250 ms). In the last part a wide QRS tachycardia is observed, although with a different,...

To investigate the impact of inhibitory processes on responses of lateral amygdaloid (LAT) neurons, intracellular recordings were obtained from identified LAT projection neurons in barbiturate-anesthetized cats. Synaptic responses evoked by perirhinal (PRH), entorhinal (ENT), basomedial, and LAT stimulation were investigated. Regardless of stimulation site, responses consisted of an excitatory ...

(1) Intracellular and extracellular recordings were made from CA1 pyramidal neurons in an in vitro rat hippocampal slice preparation, while [D-Ala2, D-Leu5]enkephalin (DADL) was applied by perfusion at a known concentration (1 to 5 X 10-7 M), in a small droplet, or by iontophoresis into the cellular and dendritic layers of the slice. The effects of DADL on synaptic potentials and membrane prope...

BACKGROUND Single premature beats were introduced in the reentrant circuit during stable atrial flutter in the canine sterile pericarditis model to test the hypotheses that (1) despite the fact that the reentrant circuit is functionally determined, there is a fully excitable gap; (2) the excitable gap in the reentrant circuit is not uniform; and (3) inhomogeneities of conduction in the reentran...

Neurons of the cochlear nucleus, nucleus magnocellularis (NM), of young chicks require excitatory afferent input from the eighth nerve for maintenance and survival. One of the earliest changes seen in NM neurons after deafferentation is an increase in intracellular calcium concentration ([Ca2+]i). This increase in [Ca2+]i is due to loss of activation of metabotropic glutamate receptors (mGluR) ...

This study describes the effects of brain-stem cholinergic laterodorsal tegmental (LDT) stimulation on the synaptic responsiveness of anterior thalamic (AT) neurons. A sample of AT cells, physiologically identified by their short-latency (less than 6.5 msec) response to mammillary body (MB) stimulation, was recorded in unanesthetized, chronically implanted cats and in urethane-anesthetized cats...

BACKGROUND Premature stimulation is used to characterize the reentrant circuit during ventricular tachycardia (VT) in patients. The goal of this study was to compare the effects of premature stimulation on functional and anatomic reentrant VT. METHODS AND RESULTS In 18 Langendorff-perfused rabbit hearts, thin layers of anisotropic left ventricular subepicardium were created by a cryoprocedure...

Non-annular accessory pathways are rare to encounter in clinical practice. We present a case of right atrial appendage posterior ventricular outflow tract pathway patient with Wolf-Parkinson-White Syndrome. N/A A 26-year-old male structurally normal heart and syndrome was referred our lab for electrophysiology study catheter ablation. He had two prior studies one unsuccessful ablation attempt w...