Melduni Rowlens M, Cullen Michael W
J Atr Fibrillation. 2012 Dec 16;5(4):654. doi: 10.4022/jafib.654. eCollection 2012 Dec.
The role of left ventricular (LV) diastolic dysfunction in predicting atrial fibrillation (AF) recurrence after successful electrical cardioversion is largely unknown. Studies suggest that there may be a link between abnormal LV compliance and the initial development, and recurrence of AF after electrical cardioversion. Although direct-current cardioversion (DCCV) is a well-established and highly effective method to convert AF to sinus rhythm, it offers little else beyond immediate rate control because it does not address the underlying cause of AF. Preservation of sinus rhythm after successful cardioversion still remains a challenge for clinicians. Despite the use of antiarrhythmic drugs and serial cardioversions, the rate of AF recurrence remains high in the first year. Current evidence suggests that diastolic dysfunction, which is associated with atrial volume and pressure overload, may be a mechanism underlying the perpetuating cycle of AF recurrence following successful electrical cardioversion. Diastolic dysfunction is considered to be a defect in the ability of the myofibrils, which have shortened against a load in systole to eject blood into the high-pressure aorta, to rapidly or completely return to their resting length. Consequently, LV filling is impaired and the non-compliant left ventricle is unable to fill at low pressures. As a result, left atrial and pulmonary vein pressure rises, and electrical and structural remodeling of the atrial myocardium ensues, creating a vulnerable substrate for AF. In this article, we review the current evidence highlighting the association of LV diastolic dysfunction with AF recurrence after successful electrical cardioversion and provide an approach to the management of LV diastolic dysfunction to prevent AF recurrence.
左心室(LV)舒张功能障碍在预测电复律成功后房颤(AF)复发中的作用尚不清楚。研究表明,左心室顺应性异常与房颤的初始发生以及电复律后房颤复发之间可能存在联系。尽管直流电复律(DCCV)是一种成熟且高效的将房颤转为窦性心律的方法,但它除了能立即控制心率外,几乎没有其他作用,因为它并未解决房颤的根本原因。成功复律后维持窦性心律对临床医生来说仍是一项挑战。尽管使用了抗心律失常药物和多次电复律,但房颤在第一年的复发率仍然很高。目前的证据表明,与心房容量和压力过载相关的舒张功能障碍可能是电复律成功后房颤复发持续循环的潜在机制。舒张功能障碍被认为是肌原纤维的一种功能缺陷,肌原纤维在收缩期对抗负荷缩短以将血液射入高压主动脉后,无法快速或完全恢复到其静息长度。因此,左心室充盈受损,顺应性降低的左心室无法在低压下充盈。结果,左心房和肺静脉压力升高,随后心房心肌发生电重构和结构重构,为房颤创造了一个易损基质。在本文中,我们回顾了当前证据,强调左心室舒张功能障碍与电复律成功后房颤复发之间的关联,并提供一种管理左心室舒张功能障碍以预防房颤复发的方法。