心房颤动对脑动脉血流的影响

目的 :观察心房颤动 (AF)对脑动脉血流的影响。方法 :选择 14例心功能代偿期AF患者作观察组 (AF组 ) ,18例同龄健康体检者作对照组。采用经颅多普勒检测仪 (TCD)以脑动脉平均血流速度 (Vm)及搏动指数 (PI)为观察指标。结果 :AF组脑动脉血流速度快慢不一 ,各动脉血管的Vm均较对照组降低 ,P <0 .0 5或 0 .0 1。AF组大脑中动脉 (MCA)、大脑前动脉 (ACA)的最大心搏平均血流速度 (MaxVm)及心室率控制在 6 0～ 10 0次 /min内时MCA的Vm与对照组比较无统计学差异 ,P >0 .0 5 ,但MCA、ACA的最小心搏平均流速 (MinVm)及心室率低于 6 0次/min时MCA的Vm较对照组显著降低 ,P <0 .0 1;AF组基底动脉 (BA)、椎动脉 (VA)及大脑后动脉 (PCA)的MaxVm、Vm、MinVm及任何心室率范围BA的Vm均较对照组Vm显著降低 ,P <0 .0 5或 0 .0 1。AF组与对照组的PI值比较无统计学意义 ,P >0 .0 5。结论 :AF对脑底动脉血流均有不同程度的影响 ,表现为Vm降低 ,供血减少。AF心室率低于 6 0次 /min对脑血流影响严重 ;AF对椎基底动脉系统的血流影响较颈内动脉系统严重。

Influence of Atrial Fibrillation on the Cerebral Artery Hemodynamics

Objective:To explore the influence of atrial fibrillation (AF) on the cerebral artery hemodynamics.Methods:14 AF patients of normal cardiac function and 18 normal subjects were studied with transcranial Doppler (TCD) of mean flow velocity(Vm) and pulsatility index (PI).Results:The Vm of AF patients was different and lower than that of normal control (P<0.01).There was no significant difference in the maximum mean flow velocity (MaxVm) of the flow MCA between AF and normal group when the heart rate (HR) was 60～100 bpm (P>0.05),but the minimum mean flow velocity(MinVm) of MCA and ACA in AF group was significantly reduced when the HR was lower than 60 bpm (P<0.01).The MaxVm,MinVm and Vm of BA,VA and PCA in AF group were significantly decreased than those in the normal group (P<0.01).There was on significant difference in the PI between AF and normal group(P<0.01).Conclusion:AF decreases the cerebral flow and the flow velocity.The effects on cerebral flow and flow velocity of the patients whose HR was lower than 60 bpm were stronger than those on the patients whose HR was at 60～100 bpm.In the same way,the effects on vertebral artery were stronger than those on interal carotid artery.