Division of Pediatric Cardiology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands.
Heart. 2011 Feb;97(3):231-6. doi: 10.1136/hrt.2010.199919. Epub 2010 Dec 6.
Right ventricular (RV) dysfunction is common in patients with corrected tetralogy of Fallot (cToF). Abnormalities in the temporal pattern of RV mechanical activation have been observed in patients with cToF, but the relationship with RV performance remains unclear. This study characterises RV performance and the temporal sequence of RV deformation in patients with cToF and healthy controls.
37 patients with cToF were compared with 18 controls. Using two-dimensional speckle tracking analysis, global RV strain was assessed. In addition, time to peak strain and the time difference between RV inlet and RV outlet (RV time delay) was assessed.
The relation between RV performance and RV time delay was assessed with linear regression analysis. Results RV strain was reduced in patients compared with controls (-20.9 ± 4.3% vs -30.7 ± 3.4%, p<0.001). Time to peak strain at the RV inlet showed no differences between patients with cToF and controls (406 ± 55 ms vs 405 ± 67 ms, p=0.429), whereas time to peak strain at the RV outlet was significantly delayed in patients with cToF (339 ± 75 ms vs 262 ± 85 ms, p=0.003). Consequently, RV time delay was significantly shorter in patients with cToF than in controls (66 ± 48 ms vs 143 ± 53 ms, p<0.001). A close relation between RV time delay and RV strain was observed (r=-0.70, p<0.001).
In patients with cToF, RV outlet deformation is delayed, causing a reduction in RV time delay which is significantly related to impairment in RV performance.
右心室(RV)功能障碍在矫正型法洛四联症(cToF)患者中很常见。已经观察到 cToF 患者 RV 机械激活的时间模式异常,但与 RV 功能的关系尚不清楚。本研究旨在描述 cToF 患者和健康对照组的 RV 功能和 RV 变形的时间顺序。
将 37 例 cToF 患者与 18 例对照进行比较。使用二维斑点追踪分析评估整体 RV 应变。此外,还评估了峰值应变时间和 RV 入口与 RV 出口之间的时间差(RV 延迟时间)。
采用线性回归分析评估 RV 功能与 RV 延迟时间的关系。结果 RV 应变在患者中较对照组降低(-20.9±4.3% vs -30.7±3.4%,p<0.001)。RV 入口的峰值应变时间在 cToF 患者和对照组之间无差异(406±55 ms vs 405±67 ms,p=0.429),而 RV 出口的峰值应变时间在 cToF 患者中明显延迟(339±75 ms vs 262±85 ms,p=0.003)。因此,cToF 患者的 RV 延迟时间明显短于对照组(66±48 ms vs 143±53 ms,p<0.001)。RV 延迟时间与 RV 应变之间存在密切关系(r=-0.70,p<0.001)。
在 cToF 患者中,RV 出口变形延迟,导致 RV 延迟时间缩短,与 RV 功能障碍显著相关。