CORONARY VASCULAR TONE AFTER CORONARY BYPASS OPERATIONS

这项临床研究验证了冠脉血流动力学假说 的患者在冠状动脉介入治疗后的即刻间隔内可能发生改变 在以下情况下可能对患者的未来进程有害的搭桥手术 无法辨认。将热稀释导管放入冠状动脉 窦道经皮穿入心脏大静脉。找到的端口 在顶端允许对前壁心肌和其他组织进行取样 近端采集了整个左心室的样本。血液样本被用来 测定局部耗氧量、酸碱平衡、乳酸、 丙酮酸、肌酸激酶和乳酸脱氢酶同工酶 浓度。进行完整的血流动力学评估 术前、术后连续用药6~8h。六 患者已经进行了完整的研究。在某些情况下，没有显著的变化 冠状动脉血管阻力、心输出量或任何生化指标 变数就会发生。其他患者表现出的变化可能与较少的 而不是最佳的收缩能力和体循环血流。心率控制 通过心房起搏和预负荷可以消除部分这种变异性。 动物研究表明，使用光纤、热稀释 导管将允许在线记录心肌代谢趋势。 这样的连续测量将允许更好地评估冠状动脉血流 未来患者研究中的动力学。

This clinical study tests the hypothesis that coronary blood flow dynamics of patients may be altered in the immediate interval after a coronary bypass procedure which may be deleterious to the patient's future course if unrecognized. A thermal dilution catheter is placed into the coronary sinus percutaneously and threaded to the great cardiac vein. Ports located at the tip allow sampling of the anterior myocardium and those more proximal sample the entire left ventricle. Blood samples are used to determine regional oxygen consumption, acid base balance, lactic acid, pyruvate, creatine kinase, and lactic dehydrogenase isoenzyme concentrations. Complete hemodynamic evaluations are performed preoperatively and in serial fashion for 6-8 hours after operation. Six patients have had complete studies. In some, no significant changes in coronary vascular resistance, cardiac output, or any of the biochemical variables occur. Other patients show changes which can be related to less than optimal contractility and systemic flow. Control of heart rate through atrial pacing and preload may eliminate some of this variability. Animal studies indicate that the use of a fiberoptic, thermodilution catheter will allow on-line documentation of myocardial metabolic trends. Such continuous measurement will allow better assessment of coronary flow dynamics in future patients studies.