Grimm R A, Stewart W J, Maloney J D, Cohen G I, Pearce G L, Salcedo E E, Klein A L
Department of Cardiology, Cleveland Clinic Foundation, Ohio 4195-5064.
J Am Coll Cardiol. 1993 Nov 1;22(5):1359-66. doi: 10.1016/0735-1097(93)90543-a.
This study assessed the function of the left atrial appendage in the pericardioversion period to gain insights into mechanisms involved in thromboembolism after cardioversion of atrial fibrillation.
Systemic embolization associated with electrical cardioversion of atrial fibrillation is thought to originate from the left atrium or left atrial appendage, or both. However, the mechanism involved is poorly understood.
We studied left atrial appendage function with transesophageal echocardiography in 20 patients with atrial fibrillation before and after successful electrical cardioversion. We measured left atrial appendage emptying and filling velocities by pulsed wave Doppler echocardiography, characterized Doppler emptying patterns, measured atrial appendage areas and assessed the presence or absence of spontaneous echo contrast or thrombus.
Organized left atrial appendage function returned in 16 (80%) of 20 patients immediately after cardioversion. Atrial appendage emptying velocities before cardioversion were greater in patients without (0.39 +/- 0.02 m/s) than in those with (0.25 +/- 0.12 m/s) spontaneous echo contrast (p = 0.045). Furthermore, emptying velocities before cardioversion were significantly greater than late diastolic emptying velocities after cardioversion (0.31 +/- 0.15 vs. 0.14 +/- 0.12 m/s, p = 0.0001), as well as in both the group with (0.25 +/- 0.12 vs. 0.13 +/- 0.13 m/s, p = 0.001) and the group without (0.39 +/- 0.02 vs. 0.15 +/- 0.12 m/s, p = 0.01) spontaneous echo contrast. In addition, left atrial and atrial appendage spontaneous echo contrast developed in 4 of 20 patients and increased in intensity in 3 of 20 patients in the immediate postcardioversion period.
Organized left atrial appendage function returns in most patients immediately after cardioversion of atrial fibrillation. However, its function is impaired compared with that before cardioversion. Furthermore, spontaneous echo contrast increased in 7 (35%) of 20 patients after cardioversion. These observations suggest that stunned left atrial appendage function after cardioversion may predispose the chamber to thrombus formation, which may play a role in the mechanism involved in the occurrence of embolization after cardioversion.
本研究评估房颤复律期左心耳的功能，以深入了解房颤复律后血栓栓塞的相关机制。
房颤电复律相关的全身性栓塞被认为起源于左心房或左心耳，或两者皆有。然而，其涉及的机制尚不清楚。
我们对20例房颤患者在成功进行电复律前后，采用经食管超声心动图研究左心耳功能。我们通过脉冲波多普勒超声心动图测量左心耳排空和充盈速度，描绘多普勒排空模式，测量心耳面积，并评估是否存在自发显影或血栓。
20例患者中有16例（80%）在复律后即刻恢复了有组织的左心耳功能。复律前无自发显影的患者左心耳排空速度（0.39±0.02 m/s）高于有自发显影的患者（0.25±0.12 m/s）（p = 0.045）。此外，复律前的排空速度显著高于复律后舒张末期的排空速度（0.31±0.15 vs. 0.14±0.12 m/s，p = 0.0001），在有自发显影的组（0.25±0.12 vs. 0.13±0.13 m/s，p = 0.001）和无自发显影的组（0.39±0.02 vs. 0.15±0.12 m/s，p = 0.01）中均如此。此外，20例患者中有4例在复律后即刻出现左心房和心耳自发显影，20例患者中有3例显影强度增加。
大多数患者在房颤复律后即刻恢复了有组织的左心耳功能。然而，与复律前相比，其功能受损。此外，20例患者中有7例（35%）在复律后自发显影增加。这些观察结果表明，复律后左心耳功能受损可能使心房易形成血栓，这可能在复律后栓塞发生的机制中起作用。
