Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan, USA.
Heart Rhythm. 2011 Feb;8(2):181-7. doi: 10.1016/j.hrthm.2010.10.030. Epub 2010 Oct 26.
Atrial stretch is thought to play a role in the development of atrial fibrillation (AF). However, the precise mechanism by which stretch contributes to AF maintenance in humans is unknown.
The purpose of this study was to determine the impact of left atrial (LA) pressure on AF frequency in patients undergoing catheter ablation of AF.
The subjects of this study were 58 consecutive patients with persistent AF (n = 40) or paroxysmal AF (n = 18) undergoing LA ablation. LA pressure was measured before ablation. Both atria and the coronary sinus were mapped, and regional dominant frequency (DF) was determined.
Mean LA pressure in the persistent AF group was significantly higher than in the paroxysmal AF group (18 ± 5 vs 10 ± 4 mmHg, P <.0001). Mean DF in the persistent AF group was also higher than in the paroxysmal AF group (6.36 ± 0.51 Hz and 5.83 ± 0.54 Hz, P = .0006). In patients with persistent AF, there was a significant correlation between LA pressure and DF at the LA appendage (r = 0.55, P = .0002). DF(max) was found at the LA appendage region in 24 (60%) of the 40 patients with persistent AF (P = .0006). In multivariate analysis, LA pressure was the only independent predictor of DF(max) in the LA appendage (P = .04, odds ratio 1.41, 95% confidence interval 1.02-1.94).
Higher LA pressure in patients with persistent AF implies that these patients are more vulnerable to stretch-related remodeling than are patients with paroxysmal AF. The DF of AF was directly related to LA pressure in patients with persistent AF. This finding suggests that atrial stretch may contribute to the maintenance of AF in humans by stabilizing high-frequency sources.
心房牵张被认为在心房颤动（AF）的发生中起作用。然而，牵张如何导致人类 AF 的维持的确切机制尚不清楚。
本研究旨在确定左心房（LA）压力对接受 AF 导管消融治疗的患者 AF 频率的影响。
本研究的对象是 58 例连续的持续性 AF（n = 40）或阵发性 AF（n = 18）患者，均行 LA 消融。消融前测量 LA 压力。标测左右心房和冠状窦，确定局部优势频率（DF）。
持续性 AF 组的平均 LA 压力明显高于阵发性 AF 组（18 ± 5 与 10 ± 4 mmHg，P <.0001）。持续性 AF 组的平均 DF 也高于阵发性 AF 组（6.36 ± 0.51 Hz 和 5.83 ± 0.54 Hz，P =.0006）。在持续性 AF 患者中，LA 压力与 LA 心耳处的 DF 呈显著相关（r = 0.55，P =.0002）。在 40 例持续性 AF 患者中有 24 例（60%）在 LA 心耳区发现 DF（max）（P =.0006）。多变量分析显示，LA 压力是 LA 心耳 DF（max）的唯一独立预测因子（P =.04，优势比 1.41，95%置信区间 1.02-1.94）。
持续性 AF 患者的 LA 压力较高意味着这些患者比阵发性 AF 患者更容易受到与牵张相关的重塑影响。持续性 AF 患者的 AF 频率与 LA 压力直接相关。这一发现表明，心房牵张可能通过稳定高频源而有助于维持人类的 AF。
