Division of Cardiology, University of Western Ontario, London, Ontario, Canada.
Circ Arrhythm Electrophysiol. 2011 Aug;4(4):510-4. doi: 10.1161/CIRCEP.111.963058. Epub 2011 Jun 10.
Inadvertent capture of the atrium will lead to spurious results during para-Hisian pacing. We sought to establish whether the stimulation-to-atrial electrogram interval at the proximal coronary sinus (stim-PCS) or high right atrium (stim-HRA) could signal inadvertent atrial capture.
Para-Hisian pacing with and without intentional atrial capture was performed in 31 patients. Stim-HRA and stim-PCS intervals were measured with atrial capture, His plus para-Hisian ventricular (H+V) capture, and para-Hisian ventricular (V) capture alone. The mean stim-HRA interval was significantly shorter with atrial capture (66 ± 18 ms) than with H+V (121 ± 27 ms, P < 0.001) or V capture alone (174 ± 38 ms, P < 0.001). The mean stim-PCS interval was significantly shorter with atrial capture (51 ± 16 ms) than with H+V (92 ± 22 ms, P<0.001) or V capture alone (146 ± 33 ms, P < 0.001). A stim-PCS < 60 ms (stim-HRA < 70 ms) was observed only with atrial capture. A stim-PCS >90 ms (stim-HRA >100 ms) was observed only in the absence of atrial capture. A stim-HRA of < 85 ms was highly specific and stim-PCS of < 85 ms highly sensitive at identifying atrial capture. Stim-HRA intervals of 75 to 97 ms and stim-PCS intervals of 65 to 88 ms were observed with either atrial, His, or para-Hisian ventricular capture without atrial capture. In this overlap zone, all patients demonstrated a stim-PCS or stim-HRA interval prolongation of at least 20 ms when the catheter was advanced to avoid deliberate atrial pacing. The QRS morphology was of limited value in distinguishing atrial capture due to concurrent ventricular or H+V capture, as observed in 20 of 31 (65%) patients.
Stim-PCS and stim-HRA intervals can be used to monitor for inadvertent atrial capture during para-Hisian pacing. A stim-PCS < 60 ms (or stim-HRA < 70 ms) and stim-PCS > 90 ms (or stim-HRA > 100 ms) were observed only with and without atrial capture, respectively, but there was significant overlap between these values. Deliberate atrial capture and loss of capture reliably identifies atrial capture regardless of intervals.
在Para-His 起搏过程中，如果无意间捕捉到心房，将会导致虚假的结果。我们试图确定近端冠状窦（stim-PCS）或高位右心房（stim-HRA）的刺激-心房电图间期是否可以提示无意中捕获心房。
对 31 例患者进行了伴有和不伴有故意心房捕获的 Para-His 起搏。在有和没有心房捕获、His 加 Para-His 心室（H+V）捕获以及单独 Para-His 心室（V）捕获的情况下，测量了 stim-HRA 和 stim-PCS 间期。带有心房捕获的 stim-HRA 平均间隔明显短于 H+V（121 ± 27 ms，P < 0.001）或单独 V 捕获（174 ± 38 ms，P < 0.001）。带有心房捕获的 stim-PCS 平均间隔明显短于 H+V（92 ± 22 ms，P < 0.001）或单独 V 捕获（146 ± 33 ms，P < 0.001）。仅在心房捕获时观察到 stim-PCS < 60 ms（stim-HRA < 70 ms）。仅在没有心房捕获时观察到 stim-PCS > 90 ms（stim-HRA > 100 ms）。stim-HRA < 85 ms 具有高度特异性，而 stim-PCS < 85 ms 则高度敏感，可用于识别心房捕获。当导管推进以避免故意心房起搏时，在心房、His 或 Para-His 心室捕获但无心房捕获的情况下，观察到 stim-HRA 间隔为 75 至 97 ms，stim-PCS 间隔为 65 至 88 ms。在这个重叠区域，所有患者在推进导管以避免故意心房起搏时，均观察到 stim-PCS 或 stim-HRA 间隔延长至少 20 ms。由于观察到 31 例中的 20 例（65%）患者存在心室或 H+V 捕获时的同时性心房捕获，因此 QRS 形态对于区分由于同时性心室或 H+V 捕获导致的心房捕获的价值有限。
在 Para-His 起搏期间，可以使用 stim-PCS 和 stim-HRA 间隔来监测无意中捕获的心房。仅在有和没有心房捕获时分别观察到 stim-PCS < 60 ms（或 stim-HRA < 70 ms）和 stim-PCS > 90 ms（或 stim-HRA > 100 ms），但这些值之间存在显著重叠。无论间隔如何，故意捕获心房和失去捕获都能可靠地识别捕获心房。
