Bortone Franco, Mazzoni Maurizio, Repossini Alberto, Campolo Jonica, Ceriani Roberto, Devoto Emmanuela, Parolini Marina, De Maria Renata, Arena Vincenzo, Parodi Oberdan
Department of Anesthesia and Cardiac Surgery, Humanitas Gavazzeni, Bergamo, Italy.
J Cardiothorac Vasc Anesth. 2003 Aug;17(4):478-85. doi: 10.1016/s1053-0770(03)00153-8.
To evaluate myocardial lactate metabolism as a marker of functional status after surgical coronary revascularization.
Single-center, prospective, cohort study.
Tertiary care teaching hospital.
Fifty patients with stable angina, ejection fraction >0.40, undergoing coronary artery bypass surgery for multiple-vessel disease.
Before (T1) and 30 minutes (T2) after coronary artery bypass grafting, the authors simultaneously sampled blood from artery and coronary sinus to determine myocardial lactate dynamics and performed transesophageal echocardiography (TEE) to assess segmental wall motion. Wall motion score index (WMSI) was calculated with an online/offline comparison. At T2, WMSI improved from 1.40 +/- 0.31 to 1.17 +/- 0.23 (p = 0.0001). Preoperatively, 2 patterns of lactate balance were found: 39 patients were lactate extractors (17% +/- 10%) and 11 were lactate producers (-11% +/- 11%). At T2, lactate metabolism was shifted towards a pattern opposite to the baseline: delta lactate extraction was -8% +/- 16% in extractors at T1 versus 7% +/- 9% in producers at T1 (p = 0.003). Changes in WMSI were not correlated with changes in lactate utilization. No single preoperative variable predicted postoperative WMSI or its changes from baseline. Cardiopulmonary bypass (CPB) time was the only significant predictor of postoperative lactate extraction by multivariate regression (r = -0.46, p = 0.001): at T2, patients in the highest CPB time quartile showed frank lactate production (-6% +/- 13%) when compared with those in the lowest quartile (15% +/- 11%, p = 0.005). However, postoperative WMSI was similar in different CPB time groups.
Myocardial lactate metabolism pattern is not associated with functional status before and early after successful coronary revascularization. CPB time was the only significant predictor of postoperative lactate extraction. Measurement of lactate does not appear to be a valuable tool to assess the coupling of myocardial regional function and metabolism in the setting of coronary artery surgery and mild-to-moderate functional impairment.
评估心肌乳酸代谢作为冠状动脉血运重建术后功能状态标志物的价值。
单中心、前瞻性队列研究。
三级护理教学医院。
50例稳定型心绞痛患者，射血分数>0.40，因多支血管病变接受冠状动脉搭桥手术。
在冠状动脉搭桥术前（T1）和术后30分钟（T2），作者同时从动脉和冠状窦采集血样以测定心肌乳酸动力学，并进行经食管超声心动图（TEE）检查以评估节段性室壁运动。通过在线/离线比较计算室壁运动评分指数（WMSI）。在T2时，WMSI从1.40±0.31改善至1.17±0.23（p = 0.0001）。术前发现两种乳酸平衡模式：39例患者为乳酸摄取者（17%±10%），11例为乳酸产生者（-11%±11%）。在T2时，乳酸代谢向与基线相反的模式转变：T1时摄取者的乳酸摄取变化量为-8%±16%，而产生者为7%±9%（p = 0.003）。WMSI的变化与乳酸利用的变化不相关。术前没有单一变量可预测术后WMSI或其相对于基线的变化。通过多因素回归分析，体外循环（CPB）时间是术后乳酸摄取的唯一显著预测因素（r = -0.46，p = 0.001）：在T2时，CPB时间处于最高四分位数的患者出现明显的乳酸产生（-6%±13%），而最低四分位数的患者为15%±11%（p = 0.005）。然而，不同CPB时间组的术后WMSI相似。
在成功的冠状动脉血运重建术前及术后早期，心肌乳酸代谢模式与功能状态无关。CPB时间是术后乳酸摄取的唯一显著预测因素。在冠状动脉手术及轻至中度功能损害的情况下，乳酸测量似乎不是评估心肌局部功能与代谢耦联的有价值工具。
