Linde C, Markewitz A, Strandberg H, Larsson B, Binner L, Schüller H
Department of Cardiology, Karolinska Hospital, Stockholm, Sweden.
Pacing Clin Electrophysiol. 2001 Nov;24(11):1664-71. doi: 10.1046/j.1460-9592.2001.01664.x.
Bipolar leads have been shown to provide superior sensing conditions compared to unipolar leads as bipolar sensing is less susceptible to interference. However, the mechanical long-term integrity and longevity of bipolar leads is inferior to that of unipolar leads. A prospective randomized, multicenter study was performed to investigate a new atrial detection configuration called combipolar sensing. This new sensing concept is designed for the use of conventional unipolar leads in the atrium and the ventricle. While the atrial stimulation is unipolar, atrial sensing is accomplished in a bipolar way using the ventricular lead tip as the indifferent electrode. A modified dual chamber pacemaker provided with this sensing concept was implanted in 26 patients. At predischarge and at the 1- and 3-month follow-ups no significant differences in atrial sensing thresholds and P wave amplitudes were found between the unipolar and the combipolar sensing configuration at rest or during provocation. Myopotential inhibition could be demonstrated in 22 patients during unipolar sensing at sensitivity settings as "low" as 2 mV. In contrast, during combipolar sensing it could only be demonstrated in one patient once and only at the highest atrial sensitivity of 0.5 mV. Combipolar atrial sensing is feasible under normal conditions and during provocation. Myopotential interference is negligible. Thus, combipolar sensing offers comparable atrial sensing to bipolar without the disadvantages of a bipolar lead.
与单极导联相比，双极导联已被证明能提供更好的感知条件，因为双极感知对干扰的敏感度较低。然而，双极导联的机械长期完整性和使用寿命不如单极导联。一项前瞻性随机多中心研究旨在调查一种名为梳状双极感知的新心房检测配置。这种新的感知概念设计用于在心房和心室中使用传统的单极导联。虽然心房刺激是单极的，但心房感知是以双极方式完成的，使用心室导联尖端作为无关电极。26例患者植入了配备这种感知概念的改良双腔起搏器。在出院前以及1个月和3个月随访时，在静息或激发状态下，单极和梳状双极感知配置之间的心房感知阈值和P波振幅均未发现显著差异。在单极感知时，灵敏度设置低至2 mV时，22例患者可出现肌电位抑制。相比之下，在梳状双极感知时，仅1例患者在心房最高灵敏度为0.5 mV时出现过一次肌电位抑制。梳状双极心房感知在正常条件和激发状态下都是可行的。肌电位干扰可忽略不计。因此，梳状双极感知可提供与双极感知相当的心房感知，且没有双极导联的缺点。
