Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
Department of Surgery, University of Auckland, Auckland, New Zealand.
Am J Physiol Gastrointest Liver Physiol. 2021 Dec 1;321(6):G656-G667. doi: 10.1152/ajpgi.00219.2021. Epub 2021 Oct 6.
Gastric distension is known to affect normal slow-wave activity and gastric function, but links between slow-wave dysrhythmias and stomach function are poorly understood. Low-resolution mapping is unable to capture complex spatial properties of gastric dysrhythmias, necessitating the use of high-resolution mapping techniques. Characterizing the nature of these dysrhythmias has implications in the understanding of postprandial function and the development of new mapping devices. In this two-phase study, we developed and implemented a protocol for measuring electrophysiological responses to gastric distension in porcine experiments. In vivo, serosal high-resolution electrical mapping (256 electrodes; 36 cm) was performed in anaesthetized pigs ( = 11), and slow-wave pattern, velocity, frequency, and amplitude were quantified before, during, and after intragastric distension. experiments ( = 6) focused on developing and refining the distension mapping methods using a surgically inserted intragastric balloon, with a variety of balloon types and distension protocols. experiments ( = 5) used barostat-controlled 500-mL isovolumetric distensions of an endoscopically introduced intragastric balloon. Dysrhythmias were consistently induced in all five gastric distensions, using refined distension protocols. Dysrhythmias appeared 23 s (SD = 5 s) after the distension and lasted 129 s (SD = 72 s), which consisted of ectopic propagation originating from the greater curvature in the region of distension. In summary, our results suggest that distension disrupts gastric entrainment, inducing temporary ectopic slow-wave propagation. These results may influence the understanding of the postprandial stomach and electrophysiological effects of gastric interventions. This study presents the discovery of temporary dysrhythmic ectopic pacemakers in the distal stomach caused by localized gastric distension. Distension-induced dysrhythmias are an interesting physiological phenomenon that can inform the design of new interventional and electrophysiological protocols for both research and the clinic. The observation of distension-induced dysrhythmias also contributes to our understanding of stretch-sensitivity in the gut and may play an important role in normal and abnormal postprandial physiology.
胃扩张已知会影响正常的慢波活动和胃功能，但慢波节律紊乱与胃功能之间的联系还知之甚少。低分辨率绘图无法捕捉胃节律紊乱的复杂空间特性，因此需要使用高分辨率绘图技术。这些节律紊乱的特征对于理解餐后功能和新的绘图设备的发展具有重要意义。在这项两阶段研究中，我们开发并实施了一项用于测量猪实验中胃扩张的电生理反应的方案。在体内，对麻醉猪（= 11）进行了浆膜高分辨率电描记图（256 个电极；36 厘米），并在胃内扩张前、中、后量化慢波模式、速度、频率和幅度。 实验（= 6）专注于使用手术插入的胃内气球开发和改进膨胀映射方法，使用各种气球类型和膨胀方案。 实验（= 5）使用内镜引入的胃内气球进行 500 毫升等容容积的测压控制膨胀。使用改进的膨胀方案，在所有五次胃膨胀中都一致地诱导了节律紊乱。节律紊乱在膨胀后 23 秒（SD = 5 秒）出现，持续 129 秒（SD = 72 秒），由起源于膨胀区域的大曲率的异位传播组成。总之，我们的结果表明，膨胀会破坏胃的同步性，导致暂时的异位慢波传播。这些结果可能会影响对餐后胃的理解以及对胃干预的电生理影响。本研究发现，局部胃扩张会导致远端胃出现暂时的节律紊乱性异位起搏点。膨胀诱导的节律紊乱是一种有趣的生理现象，可以为研究和临床应用提供新的介入和电生理方案的设计提供信息。观察膨胀诱导的节律紊乱也有助于我们理解肠道的拉伸敏感性，并可能在正常和异常餐后生理学中发挥重要作用。
