Ferguson T B, Smith P K, Buhrman W C, Lofland G K, Cox J L
Circulation. 1983 Sep;68(3 Pt 2):II27-33.
Present methods used to assess the status of myocardial preservation during cardioplegic arrest include monitoring the peripheral electrocardiogram (ECG) and ventricular myocardial temperature, and visual inspection of the heart to verify complete mechanical arrest. This study was designed to determine if these parameters are adequate to ensure complete electromechanical arrest after the application of standard cardioplegic techniques. The electrical status of the ventricle in adult mongrel dogs was monitored continuously during elective hyperkalemic hypothermic arrest for the presence of electrical activity in either the atrium or ventricle with 25 intramural electrodes, three epicardial reference electrodes, a His bundle catheter, and three peripheral ECGs. Occurrence of ventricular electrical activity was documented in the arrested heart (determined visually) when the peripheral ECG was quiescent; the activity persisted for a significant period of time before electromechanical activity could be detected by standard monitoring techniques. This electrical activity is believed to originate in the lower atrial septum and to conduct through the AV node to the ventricles at myocardial temperatures previously thought to be safe. Thus, continuous monitoring of intramural electrical activity would appear to be a more reliable technique than those currently used to determine the adequacy of myocardial preservation during elective cardioplegic arrest.
目前用于评估心脏停搏期间心肌保护状态的方法包括监测外周心电图（ECG）和心室心肌温度，以及目视检查心脏以确认完全机械性停搏。本研究旨在确定这些参数是否足以确保在应用标准心脏停搏技术后实现完全的电机械停搏。在成年杂种犬进行选择性高钾低温停搏期间，使用25个心内膜电极、3个心外膜参考电极、1根希氏束导管和3个外周心电图，持续监测心室的电状态，以检测心房或心室是否存在电活动。当外周心电图静止时，记录停搏心脏中出现的心室电活动（通过目视确定）；在通过标准监测技术检测到电机械活动之前，这种活动持续了相当长的一段时间。据信，这种电活动起源于下房间隔，并在以前认为安全的心肌温度下通过房室结传导至心室。因此，与目前用于确定选择性心脏停搏期间心肌保护是否充分的技术相比，持续监测心内膜电活动似乎是一种更可靠的技术。
