Szczechowicz Marcin, Wilczek Urszula, Lelakowski Jacek
Koło Naukowe przy Klinice Elektrokardiologii, Instytutu Kardiologii CMUJ w Krakowie.
Przegl Lek. 2010;67(3):157-60.
Permanent cardiac pacing is applied in symptomatic cases of sick sinus syndrome (SSS). The aim of our research was to characterize a group of patients suffering from SSS with low risk of developing into the first degree atrioventricular block (AVB), who are able to have the atrial pacemaker (AAI) implanted.
243 patients (mean aged 61.8 years, 22.7-90.3) with implanted AAI pacemaker due to SSS were qualified. The PQ interval was compared in the earliest found (1-119 months from implantation, SD +/- 2.7 m) and the last control examination of each patient. Mean follow-up time was 88,8 months. We took into consideration the age at the moment of implantation, basic rhythm rate, polarity of the stimulating electrode (unipolar/bipolar), and presence or absence of "rate response" option.
During the follow-up the PQ interval prolonged in 40.4% of patients, on average by 36 ms, did not change in 42.1%, and in 17.5% contracted, on average by 30 ms. The age differences of these groups were not statistically significant. Prolongation of PQ in atrial pacing was rather sudden than linear, below the certain age changes of PQ are slight and after going beyond this age it increases visibly. In our patients this crucial age is 60-70. Presence of "rate response", polarity of the stimulating electrode, basic rhythm rate did not have any influence on PQ changes. The 1st degree AVB has been developed almost in a half of our group of patients. They had longer, almost border PQ in the first examination (mean 196 ms, SD +/- 29 vs. 166 ms, SD +/- 24; p < 0.001). During on average 63 months long observation the PQ interval became longer on average by next 23 ms. In the rest of patients, during the comparable time period PQ did not change. The differences of PQ changes between these groups were strongly statistically significant (p < 0.001). The 1st degree AVB occurred in 20% of patients with initial PQ < or = 160 ms and in 53% of patients with longer PQ.
永久性心脏起搏用于病态窦房结综合征（SSS）的症状性病例。我们研究的目的是确定一组患SSS且发展为一度房室传导阻滞（AVB）风险较低、能够植入心房起搏器（AAI）的患者。
纳入243例因SSS植入AAI起搏器的患者（平均年龄61.8岁，22.7 - 90.3岁）。比较每位患者最早一次（植入后1 - 119个月，标准差±2.7个月）和最后一次对照检查时的PQ间期。平均随访时间为88.8个月。我们考虑了植入时的年龄、基础心律、刺激电极的极性（单极/双极）以及是否存在“频率应答”功能。
随访期间，40.4%的患者PQ间期延长，平均延长36毫秒；42.1%的患者PQ间期无变化；17.5%的患者PQ间期缩短，平均缩短30毫秒。这些组间的年龄差异无统计学意义。心房起搏时PQ间期延长较为突然而非呈线性，低于特定年龄时PQ变化轻微，超过该年龄后则明显增加。在我们的患者中，这个关键年龄为60 - 70岁。“频率应答”功能的存在、刺激电极的极性、基础心律对PQ变化均无影响。我们组近一半的患者发生了一度AVB。他们在首次检查时PQ间期较长，几乎达到临界值（平均196毫秒，标准差±29 vs. 166毫秒，标准差±24；p < 0.001）。在平均63个月的观察期内，PQ间期平均又延长了23毫秒。在其余患者中，在可比时间段内PQ间期无变化。这些组间PQ变化的差异具有高度统计学意义（p < 0.001）。初始PQ≤160毫秒的患者中，20%发生了一度AVB，而PQ较长的患者中这一比例为53%。
