Epicardial activation after unsuccessful defibrillation shocks in dogs.
Epicardial activation after unsuccessful defibrillation shocks in dogs.
复制标题
狗除颤不成功后心外膜激活。
DOI：
10.1152/ajpheart.1988.255.4.h902
复制
发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Ideker,RE
中科院分区：
文献类型：
--
作者：
Shibata,N;Chen,PS;Dixon,EG;Wolf,PD;Danieley,ND;Smith,WM;Ideker,RE
为了研究除颤，在电诱导纤颤的过程中对7只狗进行了电击，同时用56个心外膜电极进行了记录。电击通过左心尖部和右心房上的电极进行，在心尖部产生了一个不均匀的激波场，其电势梯度远高于脑室底部。对于不成功的0.01-至0.05-J电击，在电击后不久，在底部和顶端的许多位置都发生了激活。对于0.1~0.5J的电击，早期激活点的数目大大减少，从电击到最早记录到的激活点的潜伏期在尖端显著增加，而在底部则不明显。对于1-5-J冲击，存在1-3个早期部位，并局限于底部，从休克到这些早期部位的出现之间有较长的潜伏期。最早激活的潜伏期和位置与在正常起搏节律下给予1~5J电击诱发纤颤后相似。10J的电击成功除颤。这些发现表明，激波场至少可以有三种影响。第一，弱场不能阻止纤颤的激活前沿。第二，在正常节律的脆弱时期，较强的磁场会停止颤动，但随后会以类似于相同强度磁场的方式重新诱发纤颤。第三，一个更高的磁场可以停止纤颤，而不会重新启动它。成功的除颤需要足够强的电击，以在整个脑室产生第三个磁场强度。
To study defibrillation, shocks were given to seven dogs during electrically induced fibrillation, while recordings were made from 56 epicardial electrodes. Shocks were given via electrodes on the left ventricular apex and the right atrium, creating an uneven shock field with much higher potential gradients in the apex than in the base of the ventricles. For unsuccessful 0.01- to 0.05-J shocks, activation occurred soon after the shock at many sites in both the base and the apex. For 0.1- to 0.5-J shocks, the number of early activation sites was greatly decreased, and the latency from the shock until earliest recorded activation was greatly increased at the apex but not at the base. For 1- to 5-J shocks, one to three early sites were present and confined to the base, with a long latency between the shock and the appearance of these early sites. The latency and location of earliest activation were similar to those after 1- to 5-J shocks given to induce fibrillation during normal paced rhythm. Shocks of 10 J successfully defibrillated. These findings suggest that the shock field can have at least three effects. One, a weak field fails to halt the activation fronts of fibrillation. Two, a stronger field halts but then reinduces fibrillation in a manner similar to that of the same strength field during the vulnerable period of normal rhythm. Three, a still higher field halts fibrillation without reinitiating it. Successful defibrillation requires a shock strong enough to create this third field intensity throughout the ventricles.