Korhonen U, Kärkölä P, Takkunen J, Pokela R
Pacing Clin Electrophysiol. 1984 Jul;7(4):678-82. doi: 10.1111/j.1540-8159.1984.tb05596.x.
Epicardial electrodes are an alternative for patients in whom the transvenous approach presents technical difficulties. We have had clinical experience with two types of myocardial sutureless electrodes inserted in the anterior left ventricular wall: the 3-turn screw-in electrode (Medtronic 6917) was used in 209 patients from 1974 to 1977 and the 2-turn screw-in lead (Medtronic 6917 A) was used in 61 patients from 1978 to 1981. The initial threshold was equal and acceptable with both types of electrodes. During a follow-up period (up to 48 months), critical elevation of the pacing threshold resulting in exit block was found in 12% (25) of the patients with the 3-turn screw-in electrode and in 20% (12) of the patients with the 2-turn electrode (p less than 0.05). Elevation of the pacing threshold developed fairly early, usually within 6 months, with the 2-turn screw-in electrode, but much later, within 2-4 years, with the 3-turn electrode. During a longer follow-up time of up to 96 months the frequency of exit block increased up to 16% with the 3-turn electrode. Our results indicate that late critical elevation of the pacing threshold is surprisingly frequent with screw-in electrodes inserted into the left ventricular myocardium, and it is especially common with the 2-turn screw-in electrode.
对于经静脉途径存在技术困难的患者，心外膜电极是一种替代选择。我们有在左心室前壁插入两种类型心肌无缝合电极的临床经验：1974年至1977年，209例患者使用了三圈旋入式电极（美敦力6917）；1978年至1981年，61例患者使用了两圈旋入式导线（美敦力6917A）。两种类型电极的初始阈值相等且可接受。在随访期（最长48个月）内，三圈旋入式电极患者中有12%（25例）出现起搏阈值临界升高导致传出阻滞，两圈旋入式电极患者中有20%（12例）出现这种情况（p<0.05）。两圈旋入式电极的起搏阈值升高出现得相当早，通常在6个月内，而三圈电极则在2至4年内出现得晚得多。在长达96个月的更长随访时间内，三圈电极的传出阻滞发生率增加到16%。我们的结果表明，插入左心室心肌的旋入式电极出现起搏阈值晚期临界升高的情况出奇地频繁，尤其是两圈旋入式电极。
