Diller Gerhard-Paul, Wasan Balvinder S, Kyriacou Andreas, Patel Niket, Casula Roberto P, Athanasiou Thanos, Francis Darrel P, Mayet Jamil
International Centre for Circulatory Health, St Mary's Hospital & National Heart and Lung Institute, Imperial College, London, UK.
Eur J Cardiothorac Surg. 2008 Nov;34(5):995-9. doi: 10.1016/j.ejcts.2008.08.008. Epub 2008 Oct 1.
Coronary artery bypass graft (CABG) surgery may induce myocardial stunning and thereby affect cardiac function. We aimed to assess whether myocardial function is affected by CABG in patients with preserved preoperative systolic function.
Myocardial tissue peak velocities were recorded at the lateral and septal angle of the mitral annulus as well as at the lateral tricuspid annulus by pulsed wave tissue Doppler echocardiography before cardiac surgery, and then at 5 days, 6 weeks and 18 months after surgery.
Thirty-two consecutive patients with preserved systolic left ventricular function (31 male, 63+/-10 years) undergoing CABG (9 with cardiopulmonary bypass on-pump, 23 beating heart off-pump) were included. Peak systolic velocity on tissue Doppler echocardiography was unchanged after surgery. In contrast, peak early diastolic velocities (E') improved significantly 5 days and 6 weeks after surgery in the septal area (6.2+/-2.3 to 7.4+/-2.6 and 7.6+/-2.6 cm/s, respectively; p<0.05) and at the left ventricular lateral wall (9.1+/-3.0 to 10.1+/-3.0 and 11.3+/-2.9 cm/s, respectively; p<0.05), and then declined slowly to preoperative values after 18 months. In contrast, right ventricular E' decreased significantly immediately after surgery (9.8+/-2.7 preoperatively to 7.7+/-1.7 cm/s at 5 days, p=0.005) with only incomplete recovery over time. This was similar in both the conventional and the off-pump CABG cohort.
Left ventricular function did not deteriorate after CABG in patients with preserved preoperative systolic function. On the contrary, diastolic function improved immediately after CABG. Right ventricular function, in contrast, appeared to be damaged by surgery, to similar degrees regardless of whether patients underwent off-pump or on-pump surgery. Hypothermia and immune-inflammatory activation are, therefore, not plausible explanations for this decline in right ventricular function.
冠状动脉旁路移植术（CABG）可能诱发心肌顿抑，进而影响心功能。我们旨在评估术前收缩功能正常的患者行CABG后心肌功能是否受到影响。
采用脉冲波组织多普勒超声心动图，在心脏手术前、术后5天、6周和18个月记录二尖瓣环外侧和间隔角以及三尖瓣环外侧的心肌组织峰值速度。
纳入32例连续的术前左心室收缩功能正常的患者（男性31例，年龄63±10岁）行CABG（9例体外循环下心脏停跳，23例非体外循环心脏不停跳）。组织多普勒超声心动图的收缩期峰值速度术后无变化。相反，间隔区域术后5天和6周时舒张早期峰值速度（E'）显著改善（分别从6.2±2.3提高到7.4±2.6和7.6±2.6 cm/s；p<0.05），左心室侧壁也如此（分别从9.1±3.0提高到10.1±3.0和11.3±2.9 cm/s；p<0.05），然后在18个月后缓慢降至术前值。相比之下，右心室E'在术后立即显著降低（术前9.8±2.7降至术后5天的7.7±1.7 cm/s，p=0.005），且随时间仅不完全恢复。在传统CABG组和非体外循环CABG组中情况相似。
术前收缩功能正常的患者行CABG后左心室功能未恶化。相反，CABG后舒张功能立即改善。相比之下，右心室功能似乎因手术受损，无论患者接受非体外循环还是体外循环手术，受损程度相似。因此，低温和免疫炎症激活并非右心室功能下降的合理原因。
