Ali Sajid, Ugwu Justin, Kanjwal Yousuf
Mercy St. Vincent Hospital and Medical Center, Toledo, Ohio, USA.
Cardiology. 2016;134(4):394-7. doi: 10.1159/000444166. Epub 2016 Apr 27.
Left atrial appendage thrombus formation is a known major complication of atrial fibrillation and atrial flutter which increases the risk of embolism and stroke. This risk of thrombosis is greatly increased with a lack of anticoagulation. After conversion to a normal sinus rhythm in these arrhythmias, the risk of thrombus formation in the left atrium persists through a phenomenon termed atrial myocardial stunning.
We present the case of a patient who previously underwent successful pulmonary vein isolation and was found to be in typical isthmus-dependent atrial flutter with a questionable recurrence of atrial fibrillation. The decision was made to return for atrial flutter ablation and for evaluation of prior pulmonary vein isolation. Initially, a transesophageal echocardiogram showed a normal ejection fraction, biatrial enlargement and no left atrial appendage thrombus. Ablation of the cavotricuspid isthmus was successfully accomplished with documented bidirectional block. A transesophageal echocardiogram probe was still in place prior to planned transseptal puncture for the evaluation of pulmonary veins. A large thrombus was now observed filling the left atrial appendage. Conclusion and Objective: Atrial stunning is a transient atrial contractile dysfunction that occurs whether sinus rhythm is restored spontaneously, electrically, pharmacologically or by ablation. We know after conversion that there is higher propensity to increased spontaneous echogenic contrast and decreased velocities; however, we do not have documented knowledge of exactly how soon after the conversion to a sinus rhythm a thrombus may be seen. We demonstrate a case of acute left atrial appendage thrombus formation immediately following the successful ablation of isthmus-dependent atrial flutter. Our report validates the belief that strategies of not interrupting anticoagulation prior to the conversion of these arrhythmias should be implemented.
左心耳血栓形成是心房颤动和心房扑动已知的主要并发症，会增加栓塞和中风风险。抗凝治疗缺乏时，这种血栓形成风险会大幅增加。在这些心律失常转为正常窦性心律后，左心房血栓形成风险会通过一种称为心房心肌顿抑的现象持续存在。
我们报告一例患者，该患者此前成功接受了肺静脉隔离术，被发现处于典型的峡部依赖性心房扑动，且存在心房颤动复发可疑情况。决定再次进行心房扑动消融及评估既往肺静脉隔离情况。最初，经食管超声心动图显示射血分数正常、双房扩大且无左心耳血栓。成功完成了腔静脉三尖瓣峡部消融，并有双向阻滞记录。在计划进行经房间隔穿刺以评估肺静脉之前，经食管超声心动图探头仍在位。此时观察到一个大血栓充满左心耳。结论与目的：心房顿抑是一种短暂的心房收缩功能障碍，无论窦性心律是自发恢复、电恢复、药物恢复还是通过消融恢复都会发生。我们知道在心律转复后，自发回声增强和速度降低的倾向会增加；然而，我们尚无确切记录表明在转为窦性心律后多久可能会出现血栓。我们展示了一例在峡部依赖性心房扑动成功消融后立即发生急性左心耳血栓形成的病例。我们的报告证实了在这些心律失常转复前不中断抗凝治疗的策略应予以实施这一观点。
