猪心脏停搏期间的心房电活动及其抑制情况。

Atrial electrical activity and its suppression during cardioplegic arrest in pigs.

作者信息

Novick R J, Stefaniszyn H J, Morin J E, Tchervenkov C I, Malcolm I D, Symes J F, Dobell A R, Salerno T A

出版信息

J Thorac Cardiovasc Surg. 1983 Aug;86(2):235-41.

Abstract

Right atrial electrical activity and myocardial temperatures of all four chambers were monitored during a 1 hour period of cardioplegic arrest in 20 pigs subjected to different methods of venous cannulation and cardiac cooling. Myocardial protection was provided by systemic hypothermia (28 degrees C) and intermittent intra-aortic administration of cold (4 degrees C) hyperkalemic (20 mEq/L) crystalloid cardioplegia. The use of a single right atrial cannula for venous drainage was associated with sustained atrial activity (50 +/- 5.5 minutes) during cardioplegic arrest and the warmest right atrial (27 degrees +/- 0.2 degrees C) and right ventricular (20.5 degrees +/- 0.4 degrees C) temperatures. Separate caval cannulation with snaring and right atrial venting decreased right atrial and ventricular temperatures marginally (25.3 degrees +/- 0.5 degrees C and 19.1 degrees +/- 0.4 degrees C, respectively, p less than 0.05) but did not significantly alter the duration of atrial electrical activity (42.2 +/- 2.5 minutes, p greater than 0.05). Addition of an extracavitary right atrial drip of cold (4 degrees C) saline, 750 ml for the 1 hour aortic clamping period, reduced right atrial temperature (22.8 degrees +/- 0.4 degrees C) and activity (24.8 +/- 6.3 minutes) to a significant extent. Intracavitary irrigation of the right atrium with cold saline, in the presence of snared double caval cannulas, decreased right atrial and ventricular temperatures most dramatically (17.0 degrees +/- 0.5 degrees C and 17.5 degrees +/- 0.3 degrees C, respectively, p less than 0.05), reduced the duration of atrial electrical activity by 84% (to 8 +/- 3.9 minutes, p less than 0.01), and diminished the total number of atrial contractions per hour of aortic clamping by 88%. It is concluded that intracavitary right atrial cooling with separate snared caval cannulation is the most effective method of ensuring atrial inactivity and prolonged right heart hypothermia during cardioplegic arrest.

摘要

在20头接受不同静脉插管和心脏降温方法的猪中，在1小时的心脏停搏期间监测了所有四个腔室的右心房电活动和心肌温度。通过全身低温（28摄氏度）和间歇性主动脉内给予冷（4摄氏度）高钾（20 mEq/L）晶体心脏停搏液来提供心肌保护。使用单个右心房插管进行静脉引流与心脏停搏期间持续的心房活动（50±5.5分钟）以及最温暖的右心房（27±0.2摄氏度）和右心室（20.5±0.4摄氏度）温度相关。采用圈套法分别进行腔静脉插管和右心房排气，右心房和心室温度略有下降（分别为25.3±0.5摄氏度和19.1±0.4摄氏度，p<0.05），但并未显著改变心房电活动的持续时间（42.2±2.5分钟，p>0.05）。在1小时的主动脉阻断期加入750 ml冷（4摄氏度）盐水进行腔外右心房滴注，可显著降低右心房温度（22.8±0.4摄氏度）和活动（24.8±6.3分钟）。在圈套双腔静脉插管的情况下，用冷盐水进行右心房腔内冲洗，右心房和心室温度下降最为显著（分别为17.0±0.5摄氏度和17.5±0.3摄氏度，p<0.05），心房电活动持续时间减少84%（至8±3.9分钟，p<0.01），每小时主动脉阻断期间心房收缩总数减少88%。结论是，采用圈套法分别进行腔静脉插管的右心房腔内降温是在心脏停搏期间确保心房无活动和延长右心低温的最有效方法。