Faerestrand S, Ohm O J, Stangeland L, Heynen H, Moore A
Medical Department, University of Bergen, Haukeland Hospital, Norway.
Pacing Clin Electrophysiol. 1994 Aug;17(8):1355-72. doi: 10.1111/j.1540-8159.1994.tb02455.x.
Rate adaptive ventricular pacemakers using central venous oxygen saturation (O2Sat) to control the pacing rate have been implanted in 14 patients (mean age 71 years), with a mean follow-up period of 44 months (range 2-63 months). In eight patients the pacemakers were replaced due to signs of battery depletion after an implant duration of 39-58 months. During bicycle exercise testing the O2Sat decreased on average from 61% +/- 4% at rest to 36% +/- 4% (P < 0.0001) at peak exercise, and the maximum pacing rate was 122 +/- 5 beats/min. The time delay until the O2Sat had dropped 10%, 65%, and 90% of the total reduction during exercise was 4.8 +/- 0.9 seconds, 39.8 +/- 3.8 seconds, and 71.3 +/- 7.5 seconds, respectively. The O2Sat decreased 9.4% +/- 2% (P < 0.005) from resting supine to resting sitting. Oxygen breathing increased the telemetered O2Sat from the pacemaker by 8.4% +/- 1% (P < 0.001). During follow-up the O2Sats were relatively stable in 50% of the patients, but demonstrated significant fluctuations in the others. At 1-year invasive follow-up O2Sat measured by the pacemaker decreased 22% +/- 2%, and in blood samples from the right ventricle 22% +/- 2% from rest to 3 minutes exercise at 25 watts. There was a significant correlation between O2Sat measured by the pacemaker and in blood samples from right ventricle (n = 105; r = 0.73; P < 0.001). In two patients the O2Sat dropped significantly during pneumonia. In another patient episodes of angina pectoris was associated with low O2Sat and a concomitant fast pacing rate.
14例患者（平均年龄71岁）植入了利用中心静脉血氧饱和度（O2Sat）来控制起搏频率的频率适应性心室起搏器，平均随访期为44个月（范围2 - 63个月）。8例患者在植入39 - 58个月后因电池耗竭迹象而更换起搏器。在自行车运动试验期间，O2Sat平均从静息时的61%±4%降至运动峰值时的36%±4%（P < 0.0001），最大起搏频率为122±5次/分钟。运动期间O2Sat下降至总降幅的10%、65%和90%所需的时间延迟分别为4.8±0.9秒、39.8±3.8秒和71.3±7.5秒。从静息仰卧位到静息坐位，O2Sat下降了9.4%±2%（P < 0.005）。吸氧使起搏器遥测的O2Sat增加了8.4%±1%（P < 0.001）。随访期间，50%的患者O2Sat相对稳定，但其他患者出现了显著波动。在1年的有创随访中，起搏器测得的O2Sat从静息时下降了22%±2%，右心室血样中从静息到25瓦运动3分钟时下降了22%±2%。起搏器测得的O2Sat与右心室血样中的O2Sat之间存在显著相关性（n = 105；r = 0.73；P < 0.001）。2例患者在肺炎期间O2Sat显著下降。另1例患者心绞痛发作与低O2Sat及伴随的快速起搏频率有关。
