Friedman H S, O'Connor J, Kottmeier S, Shaughnessy E, McGuinn R
Can J Cardiol. 1987 Jun-Aug;3(5):240-5.
To determine the acute effects of atrial fibrillation on regional blood flow, measurements were made in awake dogs with this arrhythmia induced and sustained by rapid atrial stimulation. Atrial fibrillation reduced cardiac output (from 3.7 +/- 0.3 to 3.0 +/- 0.2 L/min, P less than 0.05), but mean aortic and left atrial pressures were not changed. Although average ventricular myocardial blood flow remained the same, dogs with an average basal myocardial blood flow less than 106 mL/min/100g showed an immediate increase (from 85 +/- 5 to 120 +/- 9 mL/min/100g, P less than 0.05), whereas those with a higher basal value showed a decrease (from 144 +/- 14 to 110 +/- 18 mL/min/100g, P less than 0.05). Moreover, change in myocardial blood flow with atrial pacing, at a rate equal to the average ventricular rate of atrial fibrillation, was directionally similar to that found during atrial fibrillation. However, left atrial myocardial blood flow increased significantly both during atrial fibrillation and pacing. Sustained atrial fibrillation resulted in a fall in splanchnic and renal cortical flow. Brain blood flow also decreased during atrial fibrillation. While the fall in cerebral blood flow was immediately evident, in the cerebellum and brain stem, this decrease was not statistically significant until the 15 min measurement. Also, presence of a ligated common carotid artery did not influence cerebral regional blood flow either under basal conditions or with atrial fibrillation. Thus, in awake dogs the fall in cardiac output that occurs with atrial fibrillation may be accompanied by diverse effects on regional circulations.
为了确定心房颤动对局部血流的急性影响，对通过快速心房刺激诱发并维持该心律失常的清醒犬进行了测量。心房颤动使心输出量降低（从3.7±0.3降至3.0±0.2升/分钟，P<0.05），但平均主动脉压和左心房压未改变。尽管平均心室心肌血流量保持不变，但基础心肌血流量平均低于106毫升/分钟/100克的犬显示出立即增加（从85±5增至120±9毫升/分钟/100克，P<0.05），而基础值较高的犬则出现下降（从144±14降至110±18毫升/分钟/100克，P<0.05）。此外，以与心房颤动时平均心室率相等的速率进行心房起搏时心肌血流量的变化，在方向上与心房颤动期间发现的相似。然而，左心房心肌血流量在心房颤动和起搏期间均显著增加。持续性心房颤动导致内脏和肾皮质血流量下降。心房颤动期间脑血流量也减少。虽然脑血流量的下降立即明显，但在小脑和脑干中，直到15分钟测量时这种下降才具有统计学意义。而且，结扎颈总动脉的存在在基础条件下或心房颤动时均不影响脑局部血流量。因此，在清醒犬中，心房颤动时发生的心输出量下降可能伴随着对局部循环的多种影响。
