Senzaki H, Iwamoto Y, Ishido H, Matsunaga T, Taketazu M, Kobayashi T, Asano H, Katogi T, Kyo S
Department of Paediatric Cardiology, Saitama Heart Institute, Saitama Medical University Hospital, 38 Morohongo, Moroyama, Saitama 350-0495, Japan.
Heart. 2008 Jan;94(1):70-4. doi: 10.1136/hrt.2006.114306. Epub 2007 May 31.
Recent histological studies of the aortic wall of patients with tetralogy of Fallot (TOF) have shown massive degeneration of the tunica media of the aorta. Such changes in arterial wall structure may significantly alter arterial wall mechanical properties, and thus cause abnormal arterial haemodynamics.
To test the hypothesis that after repair of TOF, there are abnormal arterial haemodynamics which are associated with aortic dilatation and which increased after load on the left ventricle.
The subjects comprised 38 patients who had undergone complete repair of TOF, and 55 control subjects. Systemic arterial haemodynamics were investigated by measuring aortic input impedance during cardiac catheterisation. The patients with TOF had significantly higher characteristic impedance (158 (43) dyne x s x cm(-5) x m(2) vs 105 (49) dyne x s x cm(-5) x m(2)) and pulse wave velocity (561 (139) cm/s vs 417 (91) cm/s) and significantly lower total peripheral arterial compliance (0.93 (0.39) ml/mm Hg/m(2) vs 1.24 (0.58) ml/mm Hg/m(2)) than the controls (for all three variables, p<0.01 vs controls), suggesting that central and peripheral arterial wall stiffness are increased after TOF repair. Additionally, patients with TOF had significantly higher arterial wave reflection than the controls (reflection coefficient: 0.21 (0.12) vs 0.16 (0.06)). These abnormalities in patients with TOF increased the pulsatile load on the left ventricle and significantly contributed to decreased cardiac output, even when right ventricular function was taken into account by multivariate regression analysis. The increase in aortic wall stiffness was closely associated with the increase in aortic root diameter.
These results indicating abnormal arterial haemodynamics after TOF repair highlight the importance of regular monitoring of the systemic arterial bed and potentially relevant cardiovascular events in long-term follow-up of TOF.
近期对法洛四联症（TOF）患者主动脉壁的组织学研究显示，主动脉中膜出现大量退变。动脉壁结构的这种变化可能会显著改变动脉壁的力学性能，进而导致异常的动脉血流动力学。
验证以下假设，即TOF修复术后存在与主动脉扩张相关的异常动脉血流动力学，且左心室负荷增加后这种异常会加剧。
研究对象包括38例接受TOF完全修复术的患者和55例对照者。通过心导管检查测量主动脉输入阻抗来研究体循环动脉血流动力学。TOF患者的特征阻抗（158（43）达因·秒·厘米⁻⁵·米² 对比 105（49）达因·秒·厘米⁻⁵·米²）、脉搏波速度（561（139）厘米/秒 对比 417（91）厘米/秒）显著更高，总外周动脉顺应性（0.93（0.39）毫升/毫米汞柱/米² 对比 1.24（0.58）毫升/毫米汞柱/米²）显著更低（所有三个变量，与对照组相比p<0.01），这表明TOF修复术后中心和外周动脉壁硬度增加。此外，TOF患者的动脉波反射显著高于对照组（反射系数：0.21（0.12）对比0.16（0.06））。即使在多变量回归分析中考虑了右心室功能，TOF患者的这些异常仍增加了左心室的搏动负荷，并显著导致心输出量降低。主动脉壁硬度的增加与主动脉根部直径的增加密切相关。
这些结果表明TOF修复术后存在异常动脉血流动力学，凸显了在TOF的长期随访中定期监测体循环动脉床及潜在相关心血管事件的重要性。
