Fenici Riccardo, Picerni Marco, Fenici Peter, Brisinda Donatella
School of Medicine and Surgery, Catholic University of the Sacred Heart, 00168 Rome, Italy.
Biomagnetism and Clinical Physiology International Center, 00144 Rome, Italy.
J Cardiovasc Dev Dis. 2025 Sep 6;12(9):343. doi: 10.3390/jcdd12090343.
Optical mapping, nanotechnology-based multielectrode arrays and automated patch-clamp allow transmembrane voltage mapping with high spatial resolution, as well as L-type calcium and inward rectifier currents measurements using native mammalian cardiomyocytes. However, these methods are limited to in vitro and ex vivo experiments, while magnetocardiography (MCG) might offer a novel approach for non-invasive preclinical safety assessments of new drugs in intact and even conscious rodents by reconstructing the ventricular action potential waveform (rVAPw) from MCG signals. This study aims to assess the feasibility of rVAPw reconstruction from MCG signals in Guinea pigs (GPs) and validate the results by comparison with simultaneously recorded epicardial ventricular monophasic action potentials (eVMAP). Unshielded MCG (uMCG) data of 18 GPs, investigated anaesthetized and awake at ages of 5, 14, and 26 months using a 36-channel DC-SQUID system, were analyzed to calculate rVAPw from MCG's current arrow map. Successful rVAPw reconstruction from averaged MCG showed good alignment with eVMAP waveforms. However, some rVAPw displayed incomplete or distorted repolarization at sites with lower MCG amplitude. 300-s uMCG averaging allowed rVAPw reconstruction in intact GPs. Occasionally distorted rVAPw suggests the need for dedicated MCG devices development, with higher density of optimized vector sensors, and modelling tailored for small animal hearts.
光学映射、基于纳米技术的多电极阵列和自动膜片钳技术可实现高空间分辨率的跨膜电压映射，以及使用天然哺乳动物心肌细胞测量L型钙电流和内向整流电流。然而，这些方法仅限于体外和离体实验，而心磁图（MCG）可能提供一种新方法，通过从MCG信号重建心室动作电位波形（rVAPw），对完整甚至清醒的啮齿动物进行新药的非侵入性临床前安全性评估。本研究旨在评估从豚鼠（GPs）的MCG信号重建rVAPw的可行性，并通过与同时记录的心外膜心室单相动作电位（eVMAP）进行比较来验证结果。使用36通道直流超导量子干涉装置系统对18只GPs在5、14和26个月大时麻醉和清醒状态下进行的非屏蔽MCG（uMCG）数据进行分析，以从MCG的电流箭头图计算rVAPw。从平均MCG成功重建的rVAPw与eVMAP波形显示出良好的一致性。然而，一些rVAPw在MCG幅度较低的部位显示出复极化不完全或扭曲。300秒的uMCG平均允许在完整的GPs中重建rVAPw。偶尔扭曲的rVAPw表明需要开发专用的MCG设备，配备更高密度的优化矢量传感器，以及针对小动物心脏量身定制的模型。
