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Ajijola, O. A.

Publications and source records attributed to Ajijola, O. A..

2 recordsLinked to original sources

Metrics of High Cofluctuation and Entropy to Describe Control of Cardiac Function in the Stellate Ganglion

Stellate ganglia within the intrathoracic cardiac control system receive and integrate central, peripheral, and cardiopulmonary information to produce postganglionic cardiac sympathetic inputs. Pathological anatomical and structural remodeling occurs within the neurons of the stellate ganglion (SG) in the setting of heart failure. A large proportion of SG neurons function as interneurons whose networking capabilities are largely unknown. Current therapies are limited to targeting sympathetic activity at the cardiac level or surgical interventions such as stellectomy, to treat heart failure. Future therapies that target the stellate ganglion will require understanding of their networking capabilities to modify any pathological remodeling. We observe SG networking by examining cofluctuation and specificity of SG networked activity to cardiac cycle phases. We investigate network processing of cardiopulmonary transduction by SG neuronal populations in porcine with chronic pacing-induced heart failure and control subjects during extended in-vivo extracellular microelectrode recordings. We find that information processing and cardiac control in chronic heart failure by the SG, relative to controls, exhibits: i) more frequent, short-lived, high magnitude cofluctuations, ii) greater variation in neural specificity to cardiac cycles, and iii) neural network activity and cardiac control linkage that depends on disease state and cofluctuation magnitude.

bioengineering

ATRIOVENTRICULAR NODAL FUNCTION, ATRIAL FIBRILLATION AND VENTRICULAR TACHYCARDIA IN GIRAFFES

Unique cardiovascular adaptations in giraffes (Giraffa Camelopardalis reticulata) have been the focus of numerous investigations for almost a century. The vertical distance between the heart and brain impose high pressure on the giraffe left ventricle leading to thickening that exceeds heart in other mammals. Yet, cardiovascular function appears to be unimpacted by these morphologic differences. Physiologically adapted atrioventricular conduction may contribute to these unique cardiovascular characteristics. Atrioventricular (AV) function was assessed to determine whether physiologically adapted AV intervals might optimize the delay between atrial and ventricular contractions. Using ambulatory and intracardiac recordings, we report a longer PR interval in giraffes than predicted by allometric scaling. Slow ventricular response during atrial fibrillation further supports species-specific atrioventricular adaptations.

zoology