Kittnar O, Riedlbauchová L, Tomis J, LoŽek M, Valeriánová A, Hrachovina M, Mlček M, Huptych M, Janoušek J, Lhotská L
Institute of Physiology, First Faculty of Medicine Charles University, Prague, Czech Republic.
Physiol Res. 2017 Dec 30;66(Suppl 4):S523-S528. doi: 10.33549/physiolres.933805.
Cardiac resynchronization therapy (CRT) has proven efficacious in reducing or even eliminating cardiac dyssynchrony and thus improving heart failure symptoms. However, quantification of mechanical dyssynchrony is still difficult and identification of CRT candidates is currently based just on the morphology and width of the QRS complex. As standard 12-lead ECG brings only limited information about the pattern of ventricular activation, we aimed to study changes produced by different pacing modes on the body surface potential maps (BSPM). Total of 12 CRT recipients with symptomatic heart failure (NYHA II-IV), sinus rhythm and QRS width >/=120 ms and 12 healthy controls were studied. Mapping system Biosemi (123 unipolar electrodes) was used for BSPM acquisition. Maximum QRS duration, longest and shortest activation times (ATmax and ATmin) and dispersion of QT interval (QTd) were measured and/or calculated during spontaneous rhythm, single-site right- and left-ventricular pacing and biventricular pacing with ECHO-optimized AV delay. Moreover we studied the impact of CRT on the locations of the early and late activated regions of the heart. The average values during the spontaneous rhythm in the group of patients with dyssynchrony (QRS 140.5+/-10.6 ms, ATmax 128.1+/-10.1 ms, ATmin 31.8+/-6.7 ms and QTd 104.3+/-24.7 ms) significantly differed from those measured in the control group (QRS 93.0+/-10.0 ms, ATmax 79.1+/-3.2 ms, ATmin 24.4+/-1.6 ms and QTd 43.6+/-10.7 ms). Right ventricular pacing (RVP) improved significantly only ATmax [111.2+/-10.6 ms (p<0.05)] but no other measured parameters. Left ventricular pacing (LVP) succeeded in improvement of all parameters [QRS 105.1+/-8.0 ms (p<0.01), ATmax 103.7+/-7.1 ms (p<0.01), ATmin 20.2+/-3.7 ms (p<0.01) and QTd 52.0+/-9.4 ms (p<0.01)]. Biventricular pacing (BVP) showed also a beneficial effect in all parameters [QRS 121.3+/-8.9 ms (p<0.05), ATmax 114.3+/-8.2 ms (p<0.05), ATmin 22.0+/-4.1 ms (p<0.01) and QTd 49.8+/-10.0 ms (p<0.01)]. Our results proved beneficial outcome of LVP and BVP in evaluated parameters (what seems to be important particularly in the case of activation times) and revealed a complete return of activation times to normal distribution when using these CRT modalities.
心脏再同步治疗（CRT）已被证明在减少甚至消除心脏不同步方面有效，从而改善心力衰竭症状。然而，机械不同步的量化仍然困难，目前CRT候选者的识别仅基于QRS波群的形态和宽度。由于标准12导联心电图仅能提供关于心室激动模式的有限信息，我们旨在研究不同起搏模式对体表电位图（BSPM）产生的变化。共研究了12例有症状心力衰竭（纽约心脏协会II-IV级）、窦性心律且QRS宽度≥120毫秒的CRT接受者以及12名健康对照者。使用Biosemi映射系统（123个单极电极）采集BSPM。在自身心律、右心室和左心室单部位起搏以及采用超声心动图优化房室延迟的双心室起搏期间，测量和/或计算最大QRS时限、最长和最短激动时间（ATmax和ATmin）以及QT间期离散度（QTd）。此外，我们研究了CRT对心脏早期和晚期激动区域位置的影响。不同步患者组在自身心律时的平均值（QRS 140.5±10.6毫秒，ATmax 128.1±10.1毫秒，ATmin 31.8±6.7毫秒，QTd 104.3±24.7毫秒）与对照组测量值（QRS 93.0±10.0毫秒，ATmax 79.1±3.2毫秒，ATmin 24.4±1.6毫秒，QTd 43.6±10.7毫秒）有显著差异。右心室起搏（RVP）仅显著改善了ATmax[111.2±10.6毫秒（p<0.05）]，但未改善其他测量参数。左心室起搏（LVP）成功改善了所有参数[QRS 105.1±8.0毫秒（p<0.01），ATmax 103.7±7.1毫秒（p<0.01），ATmin 20.2±3.7毫秒（p<0.01），QTd 52.0±9.4毫秒（p<0.01）]。双心室起搏（BVP）在所有参数上也显示出有益效果[QRS 121.3±8.9毫秒（p<0.05），ATmax 114.3±8.2毫秒（p<0.05），ATmin 22.0±4.1毫秒（p<0.01），QTd 49.8±10.0毫秒（p<0.01）]。我们的结果证明了LVP和BVP在评估参数方面的有益结果（这在激动时间方面似乎尤为重要），并揭示了使用这些CRT模式时激动时间完全恢复到正态分布。
