在Valsalva动作释放期高速血流对卵圆孔未闭右向左分流的影响

Effect of high velocity blood flow on right to left shunt in patients with patent foramen ovale during release phase of Valsalva maneuver

目的探讨Valsalva动作时血流对卵圆孔未闭右向左分流(PFO-RLS)的影响并分析原因。方法选择95例伴有晕厥、先兆性偏头疼、短暂性脑缺血发作等症状的高度怀疑卵圆孔未闭患者。所有患者行经胸超声心动图记录Valsalva动作张力期和释放期三尖瓣口血流频谱E、A、VTI的变化,对结果进行统计学分析。结果Valsalva动作释放期较张力期心脏舒张期三尖瓣口血流频谱参数E、A、VTI明显增高,差异具有统计学意义。c-TTE辅以Valsalva动作诊断PFO-RLS时,Valsalva动作释放期PFO-RLS的阳性率明显高于张力期。结论在Valsalva动作释放瞬间,右心房回心血流加速,高速血流冲击卵圆瓣使PFO-RLS明显增加。因此Valsalva动作时PFO-RLS增加主要是由高速血流冲击卵圆瓣引起的。

Objective To investigate the effect of blood flow on right to left shunt of patent foramen ovale(PFO-RLS)during Valsalva maneuver and to analyze the mechanism.Methods The study population consisted of 95 patients with high clinical suspicion of PFO who suffered from apsychia,migraine with aura,transient ischemic attack(TIA).Transthoracic echocardiography was performed to record the changes of tricuspid valve orifice blood flow spectrum E,A and VTI during action tension and release of Valsalva,and the results were statistically analyzed.Results Compared with the straining stage of Valsalva maneuver,the parameters of E,A,and VTI in the diastolic in patients with PFO-RLS during release phase of Valsalva maneuver were significantly increased,and the difference was statistically significant.The positive rate of PFO-RLS in release stage of Valsalva maneuver was significantly higher than that of straining stage during the diagnosis of PFO-RLS when c-TTE plus Valsalva maneuver was used.Conclusion At the moment of release stage of Valsalva maneuver,high velocity blood flow is formed in the right chamber.Such a high velocity blood flow rapidly push the PFO open,which result in an increase in the right to left shunt of the PFO.Therefore,the increasing of PFO-RLS caused by Valsalva maneuver is mainly caused by high velocity blood flow pushing the PFO.