Atrial fibrillation was associated with blunted posterior cerebral artery conductance responses to visual stimulation (18% vs 26% in healthy controls; P<0.05) and diminished cerebral autoregulation.
Observational
Does atrial fibrillation impair neurovascular coupling and cerebral autoregulation compared to hypertension and healthy controls?
Patients with atrial fibrillation exhibit impaired neurovascular coupling and diminished cerebral autoregulation, which may contribute to their increased risk of cognitive decline and stroke.
Absolute Event Rate: 18% vs 26%
p-value: p=< 0.05
The risk of cognitive decline and stroke is increased by atrial fibrillation (AF). We sought to determine whether neurovascular coupling and cerebral autoregulation are blunted in people with AF in comparison with age-matched, patients with hypertension and healthy controls. Neurovascular coupling was assessed using five cycles of visual stimulation for 30 s followed by 30 s with both eyes-closed. Cerebral autoregulation was examined using a sit–stand test, and a repeated squat-to-stand (0.1 Hz) manoeuvre with transfer function analysis of mean arterial pressure (MAP; input) and middle cerebral artery mean blood flow velocity (MCA V m ; output) relationships at 0.1 Hz. Visual stimulation increased posterior cerebral artery conductance, but the magnitude of the response was blunted in patients with AF (18 8 %; mean SD) and hypertension (17 8 %), in comparison with healthy controls (26 9 %) ( P < 0.05). In contrast, transmission of MAP to MCA V m was greater in AF patients compared to hypertension and healthy controls, indicating diminished cerebral autoregulation. We have shown for the first time that AF patients have impaired neurovascular coupling responses to visual stimulation and diminished cerebral autoregulation. Such deficits in cerebrovascular regulation may contribute to the increased risk of cerebral dysfunction in people with AF.
Junejo et al. (Mon,) conducted a observational in Atrial fibrillation. Atrial fibrillation vs. Hypertension patients and healthy controls was evaluated on Posterior cerebral artery conductance response to visual stimulation (p=< 0.05). Atrial fibrillation was associated with blunted posterior cerebral artery conductance responses to visual stimulation (18% vs 26% in healthy controls; P<0.05) and diminished cerebral autoregulation.