Toyono Manatomo, Harada Kenji, Tamura Masamichi, Yamamoto Fumio, Takada Goro
Department of Pediatrics, Akita University School of Medicine, Japan.
J Am Soc Echocardiogr. 2004 Apr;17(4):332-7. doi: 10.1016/j.echo.2003.12.022.
Myocardial acceleration during isovolumic contraction (IVA) by Doppler tissue imaging has been proposed to be a new index of right ventricular contractile function that is unaffected by ventricular shape or loading conditions.
We sought to assess the use of IVA to evaluate right ventricular contractile function.
In all, 22 pediatric patients with pulmonary regurgitation (PR) after repair of tetralogy of Fallot (TOF) (8 +/- 3 years) and 27 age-matched children were examined. The degree of PR (mild, moderate, and severe) for patients with TOF was on the basis of pulsed and color Doppler findings. Using Doppler tissue imaging, the peak myocardial velocities during early diastole, late diastole, systole, and isovolumic contraction were recorded.
Compared with healthy children, Doppler tissue imaging velocities for patients with TOF showed decreased myocardial velocities during early diastole (P =.007), late diastole (P <.0001), systole (P <.0001), and isovolumic contraction (P <.0001). Patients with TOF had a lower IVA when compared with healthy children (P <.0001). There was a stepwise decrease in the IVA from mild to severe PR. We found a significant relationship between the IVA and the degree of PR (r = -0.86, P <.0001).
The analysis of IVA allows the assessment of right ventricular contractile function for patients with repaired TOF and various degrees of PR.
通过多普勒组织成像测量等容收缩期心肌加速度（IVA），已被提议作为评估右心室收缩功能的一项新指标，该指标不受心室形状或负荷条件的影响。
我们旨在评估IVA用于评价右心室收缩功能的效用。
共检查了22例法洛四联症（TOF）修复术后患有肺动脉反流（PR）的儿科患者（8±3岁）以及27名年龄匹配的儿童。TOF患者的PR程度（轻度、中度和重度）基于脉冲和彩色多普勒检查结果确定。使用多普勒组织成像记录舒张早期、舒张晚期、收缩期和等容收缩期的心肌峰值速度。
与健康儿童相比，TOF患者的多普勒组织成像速度显示舒张早期（P = 0.007）、舒张晚期（P < 0.0001）、收缩期（P < 0.0001）和等容收缩期（P < 0.0001）的心肌速度降低。与健康儿童相比，TOF患者的IVA较低（P < 0.0001）。从轻度到重度PR，IVA呈逐步下降趋势。我们发现IVA与PR程度之间存在显著相关性（r = -0.86，P < 0.0001）。
对IVA的分析有助于评估TOF修复术后伴有不同程度PR患者的右心室收缩功能。
