Mossahebi Sina, Shmuylovich Leonid, Kovács Sándor J
Cardiovascular Biophysics Laboratory, Cardiovascular DivisionWashington University School of Medicine, St. Louis, MO, USA.
J Atr Fibrillation. 2013 Oct 31;6(3):878. doi: 10.4022/jafib.878. eCollection 2013 Oct-Nov.
Echocardiographic diastolic function (DF) assessment remains a challenge in atrial fibrillation (AF), because indexes such as E/A cannot be used and because chronic, rate controlled AF causes chamber remodeling. To determine if echocardiography can accurately characterize diastolic chamber properties we compared 15 chronic AF subjects to 15, age matched normal sinus rhythm (NSR) subjects using simultaneous echocardiography-cardiac catheterization (391 beats analyzed). Conventional DF parameters (DT, Epeak, AT, Edur, E-VTI, E/E') and validated, E-wave derived, kinematic modeling based chamber stiffness parameter (k), were compared. For validation, chamber stiffness (dP/dV) was independently determined from simultaneous, multi-beat P-V loop data. Results show that neither AT, Epeak nor E-VTI differentiated between groups. Although DT, Edur and E/E' did differentiate between groups (DTNSR vs. DTAF p < 0.001, EdurNSR vs. EdurAF p < 0.001, E/E'NSR vs. E/E'AF p < 0.05), the model derived chamber stiffness parameter k was the only parameter specific for chamber stiffness, (kNSR vs. kAF p <0.005). The invasive gold standard determined end-diastolic stiffness in NSR was indistinguishable from end-diastolic (i.e. diastatic) stiffness in AF (p = 0.84). Importantly, the analysis provided mechanistic insight by showing that diastatic stiffness in AF was significantly greater than diastatic stiffness in NSR (p < 0.05). We conclude that passive (diastatic) chamber stiffness is increased in normal LVEF chronic, rate controlled AF hearts relative to normal LVEF NSR controls and that in addition to DT, the E-wave derived, chamber stiffness specific index k, differentiates between AF vs. NSR groups, even when invasively determined end-diastolic chamber stiffness fails to do so.
超声心动图舒张功能（DF）评估在心房颤动（AF）中仍然是一项挑战，这是因为诸如E/A等指标无法使用，还因为慢性、心率控制的房颤会导致心房重构。为了确定超声心动图能否准确描述舒张期心房特性，我们使用同步超声心动图-心导管检查（分析了391次心跳），将15名慢性房颤患者与15名年龄匹配的正常窦性心律（NSR）患者进行了比较。比较了传统的DF参数（DT、E峰、AT、Edur、E-VTI、E/E'）以及经过验证的、基于E波运动学建模得出的心房僵硬度参数（k）。为进行验证，通过同步多搏P-V环数据独立测定心房僵硬度（dP/dV）。结果显示，AT、E峰和E-VTI均无法区分两组。尽管DT、Edur和E/E'确实能区分两组（DTNSR与DTAF，p<0.001；EdurNSR与EdurAF，p<0.001；E/E'NSR与E/E'AF，p<0.05），但模型得出的心房僵硬度参数k是唯一特定于心房僵硬度的参数（kNSR与kAF，p<0.005）。有创金标准测定的NSR舒张末期僵硬度与AF舒张末期（即舒张期）僵硬度无显著差异（p = 0.84）。重要的是，该分析通过显示AF的舒张期僵硬度显著大于NSR的舒张期僵硬度（p<0.05）提供了机制性见解。我们得出结论，相对于正常左心室射血分数（LVEF）的NSR对照组，正常LVEF的慢性、心率控制的房颤心脏的被动（舒张期）心房僵硬度增加，并且除DT外，基于E波得出的、特定于心房僵硬度的指标k能够区分AF组与NSR组，即使有创测定的舒张末期心房僵硬度无法做到这一点。
