Division of Paediatric Cardiology, Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, University of Hong Kong, 102 Pokfulam Road, Hong Kong, China.
J Am Soc Echocardiogr. 2012 Apr;25(4):393-400. doi: 10.1016/j.echo.2012.01.003. Epub 2012 Jan 31.
The aim of this study was to test the hypothesis that dyssynchronous contraction of functional single ventricles occurs in Fontan patients and is related to indices of myocardial deformation and global ventricular function.
Twenty patients with tricuspid atresia (mean age, 23.5 ± 7.1 years) were studied 17.8 ± 3.8 years after undergoing the Fontan procedure. Three-dimensional echocardiographic data were acquired for determination of left ventricular (LV) volumes and systolic dyssynchrony indices. LV myocardial deformation was determined using speckle-tracking echocardiography. Calibrated integrated backscatter intensity was measured as an index of myocardial fibrosis. The results were compared with those in 20 controls.
Compared with controls, patients had significantly greater systolic dyssynchrony indices (6.13 ± 1.32% vs 4.06 ± 0.84%, P < .001). The prevalence of LV mechanical dyssynchrony (systolic dyssynchrony index > 5.74%) in patients was 55% (95% confidence interval, 32%-77%). LV global systolic longitudinal, radial, and circumferential strain (P < .001 for all), longitudinal systolic (P < .001) and early diastolic (P < .001) strain rate, and circumferential systolic (P < .001) and early diastolic (P = .009) strain rate were significantly lower in patients than in controls, while the average calibrated integrated backscatter was higher (P < .001). Patients with LV dyssynchrony (n = 11) had lower global LV longitudinal strain (P = .02), reduced LV ejection fractions (P = .002), and higher average calibrated integrated backscatter (P = .03) compared with those without LV dyssynchrony (n = 9).
A high proportion of patients with tricuspid atresia after the Fontan operation exhibit LV mechanical dyssynchrony, which may in part be related to myocardial fibrosis and has implications for myocardial deformation and global ventricular function.
本研究旨在验证以下假设，即功能性单心室收缩不同步发生在 Fontan 患者中，并且与心肌变形和整体心室功能的指标相关。
研究了 20 例三尖瓣闭锁患者（平均年龄 23.5 ± 7.1 岁），他们在接受 Fontan 手术后 17.8 ± 3.8 年接受了研究。获取三维超声心动图数据以确定左心室（LV）容积和收缩不同步指数。使用斑点追踪超声心动图确定 LV 心肌变形。测量校准后反向散射强度作为心肌纤维化的指标。将结果与 20 例对照进行比较。
与对照组相比，患者的收缩不同步指数明显更大（6.13 ± 1.32%比 4.06 ± 0.84%，P <.001）。患者 LV 机械不同步（收缩不同步指数>5.74%）的患病率为 55%（95%置信区间，32%-77%）。LV 整体收缩纵向、径向和周向应变（所有 P <.001）、纵向收缩（P <.001）和早期舒张（P <.001）应变率以及周向收缩（P <.001）和早期舒张（P =.009）应变率均明显低于对照组，而平均校准反向散射较高（P <.001）。与无 LV 不同步的患者（n = 9）相比，LV 不同步（n = 11）的患者的整体 LV 纵向应变较低（P =.02），LV 射血分数降低（P =.002），平均校准反向散射较高（P =.03）。
相当一部分接受 Fontan 手术后的三尖瓣闭锁患者存在 LV 机械不同步，这可能部分与心肌纤维化有关，并对心肌变形和整体心室功能有影响。
