Feedback coherence from intracranial pressure to RR interval was significantly enhanced during the occurrence of B-Waves compared to baseline, indicating increased directional coupling.
Observational (n=12)
Does the occurrence of ICP B-Waves alter the causal coherence and generalized synchronization between intracranial pressure and heart rate variability in patients undergoing normal pressure hydrocephalus diagnosis?
The study demonstrates enhanced directional coupling from intracranial pressure to heart rate variability during ICP B-Waves in patients with normal pressure hydrocephalus.
Causal coherence and generalized synchronization (GS) index were extracted from beat-to-beat mean intracranial pressure (ICP) and intervals between consecutive normal sinus heart beats (RR interval) that were recorded from 12 patients undergoing normal pressure hydrocephalus diagnosis. Data were organized into two groups including an ICP B-Wave group and a baseline control group. Maximal classic coherence (CC) between ICP and RR interval within 0.04, 0.15 Hz was found to be significantly greater than zero for both B-Wave and control groups with B-Wave CC greater than that of the baseline group. Causal coherence analysis further revealed that feedforward coherence due to RR interval's effect on ICP always exists for both B-Wave and baseline ICP state and no significant difference exists between two groups. On the other hand, feedback coherence from ICP to RR interval was enhanced during the occurrence of B-Wave. This finding regarding the enhanced directional, from ICP to RR interval, coupling between ICP and RR interval was also confirmed by a modified GS measure.
Hu et al. (Wed,) conducted a observational in Normal pressure hydrocephalus (n=12). ICP B-Wave state vs. Baseline control state was evaluated on Causal coherence and generalized synchronization index between ICP and RR interval. Feedback coherence from intracranial pressure to RR interval was significantly enhanced during the occurrence of B-Waves compared to baseline, indicating increased directional coupling.